U.S. patent application number 14/292112 was filed with the patent office on 2017-03-09 for stretch valve balloon catheter and methods for producing and using same.
This patent application is currently assigned to Mayser, LLC.. The applicant listed for this patent is Mayser, LLC.. Invention is credited to Gary A. KALSER, James Leone, Gregory L. MAYBACK, Leonard PINCHUK.
Application Number | 20170065798 14/292112 |
Document ID | / |
Family ID | 51530854 |
Filed Date | 2017-03-09 |
United States Patent
Application |
20170065798 |
Kind Code |
A9 |
PINCHUK; Leonard ; et
al. |
March 9, 2017 |
Stretch Valve Balloon Catheter and Methods for Producing and Using
Same
Abstract
A safety balloon catheter includes a flexible, multi-lumen
balloon catheter and a hollow barbell-shaped stretch valve. The
balloon catheter has a proximal catheter end, a balloon defining a
balloon interior to be inflated with an inflation fluid, a hollow
inflation lumen extending through the catheter to the balloon
interior and shaped to convey the inflation fluid to and from the
balloon interior, and a hollow second lumen parallel to the
inflation lumen; and a balloon drainage port fluidically connecting
the balloon interior to the second lumen. The stretch valve is
shaped to permit a fluid to pass therethrough and positioned in the
second lumen to at least partially slide therein such that, in a
steady state, a distal barbell end of the stretch valve prevents
the inflation fluid from passing through the drainage port and, in
an actuated state, the distal barbell end slides within the second
lumen to permit the inflation fluid to pass through the drainage
port and into the second lumen.
Inventors: |
PINCHUK; Leonard; (Miami,
FL) ; KALSER; Gary A.; (Winter Park, FL) ;
MAYBACK; Gregory L.; (Cooper City, FL) ; Leone;
James; (Pittsburgh, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mayser, LLC. |
Fort Lauderdale |
FL |
US |
|
|
Assignee: |
Mayser, LLC.
Fort Lauderdale
FL
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20140276663 A1 |
September 18, 2014 |
|
|
Family ID: |
51530854 |
Appl. No.: |
14/292112 |
Filed: |
May 30, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14024440 |
Sep 11, 2013 |
9044571 |
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14292112 |
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13707752 |
Dec 7, 2012 |
8591497 |
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14024440 |
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13862163 |
Apr 12, 2013 |
9056192 |
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13707752 |
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13868376 |
Apr 23, 2013 |
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13862163 |
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14024151 |
Sep 11, 2013 |
9272120 |
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13868376 |
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13707752 |
Dec 7, 2012 |
8591497 |
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14024151 |
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13713205 |
Dec 13, 2012 |
9005165 |
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13707752 |
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13868376 |
Apr 23, 2013 |
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13713205 |
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13707752 |
Dec 7, 2012 |
8591497 |
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13868376 |
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13862163 |
Apr 12, 2013 |
9056192 |
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13707752 |
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13862163 |
Apr 12, 2013 |
9056192 |
|
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13862163 |
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13707752 |
Dec 7, 2012 |
8591497 |
|
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13862163 |
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13713205 |
Dec 13, 2012 |
9005165 |
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13707752 |
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12943453 |
Nov 10, 2010 |
8382708 |
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13713205 |
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61637690 |
Apr 24, 2012 |
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61637690 |
Apr 24, 2012 |
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61637690 |
Apr 24, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 25/10185 20131105;
A61M 25/0017 20130101; A61M 2025/1093 20130101 |
International
Class: |
A61M 25/10 20060101
A61M025/10; A61M 25/00 20060101 A61M025/00 |
Claims
1. A safety balloon catheter, comprising: a flexible, multi-lumen
balloon catheter having: a proximal catheter end; a balloon
defining a balloon interior to be inflated with an inflation fluid;
a hollow inflation lumen extending through the catheter to the
balloon interior and shaped to convey the inflation fluid to and
from the balloon interior; a hollow second lumen parallel to the
inflation lumen; and a balloon drainage port fluidically connecting
the balloon interior to the second lumen; and a hollow
barbell-shaped stretch valve: shaped to permit a fluid to pass
therethrough; and positioned in the second lumen to at least
partially slide therein such that: in a steady state, a distal
barbell end of the stretch valve prevents the inflation fluid from
passing through the drainage port; and in an actuated state, the
distal barbell end slides within the second lumen to permit the
inflation fluid to pass through the drainage port and into the
second lumen.
2. The safety catheter according to claim 1, wherein the inflation
lumen is fluidically connected to the balloon interior through at
least one inflation port.
3. The safety catheter according to claim 2, wherein the balloon
drainage port is a plurality of balloon drainage ports each
fluidically connecting the balloon interior to the second
lumen.
4. The safety catheter according to claim 3, wherein: the drainage
port is a plurality of drainage ports each fluidically connecting
at least one of the balloon interior and the inflation lumen to the
second lumen; and the stretch valve: in the steady state, positions
the distal barbell end of the stretch valve in the second lumen to
prevent fluid from passing through the plurality of drainage ports;
and in the actuated state, the distal barbell end slides within the
second lumen to permit the inflation fluid to pass through the
plurality of drainage ports.
5. The safety catheter according to claim 1, wherein the balloon
has a balloon proximal end; the balloon catheter further comprises
a stretch portion between the proximal catheter end and the balloon
proximal end; the actuated state of the stretch valve is a
stretched state of the stretch portion at a pull force of between
approximately 1 pound and approximately 15 pounds applied to the
proximal shaft portion.
6. The safety catheter according to claim 1, wherein the balloon
has a balloon proximal end; the balloon catheter further comprises
a stretch portion between the proximal catheter end and the balloon
proximal end; the actuated state of the stretch valve is a
stretched state of the stretch portion at a pull force of between
approximately 1 pound and approximately 5 pounds applied to the
proximal shaft portion.
7. The safety catheter according to claim 1, wherein the balloon
has a balloon proximal end; the balloon catheter further comprises
a stretch portion between the proximal catheter end and the balloon
proximal end; the actuated state of the stretch valve is a
stretched state of the stretch portion at a pull force of between
approximately 1.5 pounds and approximately 2 pounds applied to the
proximal shaft portion.
8. The safety catheter according to claim 5, wherein, when the
balloon portion is inflated with a fluid and a pull force of
greater than approximately 15 pounds is applied to the stretch
portion, the stretch valve meets the stretched state and thereby
deflates the inflated hollow balloon portion.
9. The safety catheter according to claim 5, wherein, when the
balloon portion is inflated with a fluid and a pull force of
greater than approximately 5 pounds is applied to the stretch
portion, the stretch valve meets the stretched state and thereby
deflates the inflated hollow balloon portion.
10. The safety catheter according to claim 5, wherein, when the
balloon portion is inflated with a fluid and a pull force of
greater than approximately 2 pounds is applied to the stretch
portion, the stretch valve meets the stretched state and thereby
deflates the inflated hollow balloon portion.
11. The safety catheter according to claim 1, wherein: the balloon
has a proximal end; and the proximal barbell end of the stretch
valve is proximal of the proximal end of the balloon.
12. A safety balloon catheter, comprising: a flexible, multi-lumen,
balloon catheter having: a proximal catheter end; a balloon having
a proximal balloon end and defining a balloon interior to be
inflated with an inflation fluid; a drain lumen; and a balloon
drainage port fluidically connecting the balloon interior to the
drain lumen; and a hollow stretch valve: shaped to permit fluid to
pass therethrough; and positioned in the second lumen to at least
partially slide therein such that: in a steady state, a distal
barbell end of the stretch valve prevents the inflation fluid from
passing through the drainage port; and in a stretched state when a
length between the proximal catheter end and the proximal balloon
end is elongated between approximately 5 percent and approximately
200 percent, the distal barbell end slides within the drain lumen
to permit the inflation fluid to pass through the drainage port and
into the drain lumen.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application: [0002] is a continuation-in-part of U.S.
patent application Ser. No. 11/339,258, filed Jan. 25, 2006, now
U.S. Pat. No. 7,883,503 (which application claims the benefit under
35 U.S.C. .sctn.119(e) of U.S. Provisional Patent Application Nos.
60/647,204 and 60/647,205, both filed Jan. 26, 2005); [0003] is a
continuation-in-part of U.S. patent application Ser. No.
12/943,453, filed Nov. 10, 2010 (which application claims the
benefit under 35 U.S.C. .sctn.119(e) of U.S. provisional
application No. 61/260,271 filed Nov. 11, 2009); [0004] is a
continuation-in-part of U.S. patent application Ser. No.
13/707,752, filed Dec. 7, 2012 (which application claims the
benefit under 35 U.S.C. .sctn.119(e) of U.S. provisional
application No. 61/637,690, filed Apr. 24, 2012); [0005] is a
continuation-in-part of U.S. patent application Ser. No.
13/713,205, filed Dec. 13, 2012; [0006] is a continuation-in-part
of U.S. patent application Ser. No. 13/862,163, filed Apr. 12, 2013
(which application claims the benefit under 35 U.S.C. .sctn.119(e)
of U.S. provisional application No. 61/637,690, filed Apr. 24,
2012); [0007] is a continuation-in-part of U.S. patent application
Ser. No. 13/868,376, filed Apr. 23, 2013 (which application claims
the benefit under 35 U.S.C. .sctn.119(e) of U.S. provisional
application No. 61/637,690, filed Apr. 24, 2012); [0008] is a
continuation-in-part of U.S. patent application Ser. No.
14/024,151, filed Sep. 11, 2013; and [0009] is a
continuation-in-part of U.S. patent application Ser. No.
14/024,440, filed Sep. 11, 2013, the prior applications are hereby
incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0010] 1. Field of the Invention
[0011] The present invention relates to a catheter, especially an
automatically deflating balloon catheter with a stretch valve and
methods for using and manufacturing such a catheter.
[0012] 2. Description of Related Prior Art
[0013] A number of conventional balloon catheters exist in the
prior art. Some catheters are used to drain the bladder of a
patient during surgical procedure or to treat bladder and/or
urethra or prostate conditions, for example. Other catheters are
used to occlude a lumen, such as a blood vessel, for various
reasons (e.g., isolation, angioplasty, valvuloplasty), to pull a
thrombus out of a blood vessel, or to dilates strictures. Further
catheters are used to provide assistance with breathing, such as
endotracheal tubes. One example is a common balloon catheter
referred to as a Foley catheter, which is widely used today for
treating and draining a patient's bladder. The Foley catheter is
shown in FIG. 1 and has a multi-lumen shaft 1 that is disposed in
the urethra 10, a balloon portion 3 disposed at the distal end of
the shaft 1, a fluid drain section 4 disposed at the distal end of
the balloon 3, and a curved or straight, distal guiding tip 5 at
the distal-most end of the entire catheter. When placed properly,
the proximal-most side of the inflated balloon 3 rests on the
interior wall 31 of the bladder 30, entirely blocking off the
bladder-urethral junction 11 connecting the bladder 30 and the
urethra 10. In such a position, the fluid drain section 4 allows
continuous drainage of the bladder 30 and the balloon 3 virtually
prevents the catheter from slipping out of the bladder. This
ideally inserted position is shown in FIG. 1. As used herein, a
fluid can be either a liquid or a gas. Exemplary fluids for
inflating a balloon 3 are saline, sterile water, air, or carbon
dioxide gas. Exemplary fluids drained by the catheters mentioned
herein include urine and blood.
[0014] Basically, the balloon catheter has a tube-like body with
two lumens passing therethrough. The larger lumen is open to the
treatment location for drainage of the fluid (e.g., urine in the
bladder) distally or upstream and empties into a non-illustrated
ex-corporeal bag (proximally or downstream) for eventual disposal.
A smaller lumen is used to inflate (and deflate) the balloon 3 with
sterile water (typically) using a syringe attached to the inflation
lumen fitting 260 (see, e.g., FIG. 3). When inflated in the
bladder, for example, the catheter is substantially prevented from
sliding out of the urethra in use.
[0015] A conventional balloon 3 has a substantially constant
balloon wall thickness. The balloon 3 is fixed to the outer surface
of a fluid drainage line (not illustrated in FIG. 1) and is not
intended to be removed therefrom or to burst thereon unless an
extraordinary amount of inflation occurs. If such an event happens,
the material of the balloon will open at a random location based
upon the microscopic fractures or weaknesses in the material
itself. Such a tearing event is not supposed to occur under any
circumstances during use with a patient.
[0016] Prior art urinary catheters are not constructed to prevent
tearing of the urethra during a catheter implanting procedure and
are not constructed to break in any predefined way. Prior art
catheters are designed to deflate only when actively deflated,
either by a syringe similar to the one that inflated it or by
surgery after the physician diagnoses the balloon as not being able
to deflate, in which circumstance, a procedure to pop the balloon
surgically is required.
[0017] Over 96 million indwelling catheters are sold worldwide on
an annual basis. Twenty four million catheters are sold to
hospitals in the U.S. There are numerous complications associated
with those catheters that need to be prevented. These complications
are responsible for increases in hospital stays, excessive
bleeding, mortality, as well as morbidity. They also cause an
increased expense and burden on the already-stressed health care
system.
[0018] The complications result from several different mechanisms.
First, and probably most common, is improper placement of the
catheter. Because of the unique anatomy of the male urethra,
placing a urethral catheter for urinary drainage can be difficult.
A problem arises when the physician, technician, or nurse thinks
that the catheter is actually in a proper position when it is not.
The proper position for the catheter is with the balloon located in
the cavity of the bladder. In this position, the tip distal to the
balloon is located in the bladder and is used to drain the bladder
cavity of urine.
[0019] For placement of this catheter in the bladder 30 in the
ideal position, however, the physician or technician has no visual
aid. As shown in FIG. 1, the wall 40 defining the bladder-urethral
junction 11 is very short in the longitudinal direction of the
urethra 10. If the physician inserts the catheter too far into the
bladder 30, no damage occurs from balloon inflation; however, there
is a possibility of leakage around the balloon 3, which, under
normal conditions, actually helps to lubricate the urethra 10. In
such a case, gentle proximal movement of the shaft 1 will place the
proximal side of the balloon 3 against the bladder-urethral
junction 11. The bladder 30 can then easily expand and stretch to
compensate for the balloon 3. A normal bladder capacity is 400 cc
to 500 cc. A normal balloon capacity is approximately 10 cc to 12
cc although larger balloons are sometimes used. A typical balloon
is 5 cc, however, most clinicians put 10 cc of water in the balloon
for inflation. With 5 cc of water in the balloon, the diameter is
approximately 2 cm and with 10 cc the diameter is approximately 2.5
cm.
[0020] Complications occur when the technician and/or nurse
inflates the balloon when the balloon is not in the bladder. If the
technician does not insert the catheter in far enough, then the
balloon 3 will be inflated within the urethra 10--a condition that,
while common, is to be avoided at an costs and is a frequent cause
of bladder infections created during a hospital or clinic visit.
Infections arise because inflation of the bladder 3 inside the
urethra 10 causes the urethra 10 to stretch too far and tear. Even
though the urethra 10 is a flexible tube, it has limits to which it
can be safely stretched from within. Almost every balloon catheter
has a balloon outer diameter/circumference that well-exceeds the
safe stretching limit of the urethra 10. Therefore, if the balloon
catheter is not inserted far enough, inflation of the balloon 3
will cause serious injury to the urethra 10. This is especially
true with elderly patients who have urethras that are not as
elastic as younger patients. Also, just as important is the change
in anatomy of older males, in particular, the prostatic portion of
the urethra. With age, the prostate becomes larger and, sometimes,
the catheter cannot be advanced through the prostatic portion of
the urethra. When this occurs, the technician does not insert the
catheter all the way into the bladder and inflates the balloon
within the urethra. Alternatively, strictures, i.e., scar tissue,
cause the catheter to halt and further pressure tears the urethral
wall to create a new, unintended passage. Both of these improper
insertions cause severe bleeding and damage.
[0021] The elastomeric balloon of present-day catheter products
requires relatively high pressures to initiate inflation and expand
to an expected full-diameter shape upon over-inflation. As such,
when incorrectly placed in the urethra, the rapid inflation,
combined with the high-pressure, causes the balloon to tear the
surrounding membrane, referred to as the mucosa. Tearing of the
urethra 10 in this way causes bleeding and allows bacteria to enter
into the bloodstream at the tear site, thus causing the subsequent
bladder infection and, eventually, sepsis. Significant bleeding can
become life threatening. The urethra can normally dilate several
millimeters; however, when the balloon is inflated, this dilation
is usually several centimeters. Also, without sufficient and
immediate venting of the balloon inflation fluid after improper
placement, an accidental or intentional pull on the catheter
externally can and does cause extensive bodily harm to the
patient.
[0022] Life threatening bleeds, especially in patients who are
anticoagulated, can and do occur. Also, when the urine is infected,
as in immunocompromised patients and the elderly, the bacteria
enter the blood stream and can cause serious infections (e.g.,
sepsis), which frequently can lead to death. If the patient
survives the initial trauma, then long-term complications, such as
strictures, can and usually do occur. Strictures cause narrowings
within the urine channel and usually require additional procedures
and surgeries to correct.
[0023] Other mechanisms of catheter-induced injuries are
inadvertent manipulation of the tubing or dislodging of the
balloon--caused when the catheter is pulled from outside the
patient due to a sudden jerk or tension. This commonly happens when
the patient is ambulating or traveling from the bed to the commode
or bathroom. The tubing may inadvertently become fixed while the
patient is still moving, at which time a sudden jerk is imparted
upon the balloon and pulls the balloon into the urethra, which
tears the urethra, causing severe pain and bleeding. Injury caused
by the improper, inadvertent, and/or early removal of an inflated
balloon catheter is referred to as iatrogenic injury (also referred
to as an in-hospital injury). Hundreds of thousands of such
iatrogenic injuries occur each year--all of which need to be
prevented, not only for patient safety, but also because the cost
imposed on the medical health industry for each injury is
enormous.
[0024] Yet another scenario occurs when the patient deliberately
pulls on the catheter, thereby causing self-induced pain and injury
to the urethra. This commonly happens in confused patients, for
example, patients in nursing homes who have a disease or cognitive
dysfunction problem, such as Alzheimer's disease, or other diseases
that make the patient unable to understand the necessity of having
a catheter. Confusion occurs when the patient has a spasm causing
pain and a strong urge to urinate. During the spasm, the confused
patient often tugs and pulls on a catheter, which results in
injury. Like iatrogenic injuries, these self-induced injuries must
be prevented. In the particular case of injury caused by catheter
withdrawal when the balloon is inflated (either iatrogenic or
self-induced), hospitals have categorized such injuries as "never
events"--occurrences that should never happen. Under such
circumstances, insurance typically does not cover the resulting
extensive medical expenses.
[0025] The injuries mentioned herein are not limited to males and
also cause severe damage to the female bladder and urethra. The
injuries can also occur post-surgically, which makes the damage
even more severe. One common situation where injury is caused is
when the patient is medicated with morphine or other analgesics
that render the patient confused and unable to make rational
decisions. Feeling the foreign body inside the urethra, the
confused patient does not know to leave it alone and, instead,
gives it the injury-causing tug. These injuries have been
well-documented and are not limited to adults. Numerous injuries
are documented in pediatric patients.
[0026] Usually, it takes time to make a diagnosis of patient-caused
catheter injury. Immediately after diagnosing the injury, a
technician needs to deflate the catheter. However, once the urethra
is torn, replacing the damaged catheter with another catheter is
quite difficult and, in fact, exacerbates the injury. Sometimes,
the patient has to be taken to the operating room to replace a
urinary drainage tube once the injury occurs. Because catheters and
leg bags are now used routinely in certain situations during home
health care, this scenario is not limited to hospitals and occurs
at nursing homes and patients' homes as well.
[0027] Most of the recent catheter technology has been focused on
reducing urinary tract infections that are caused by catheters,
injuries that are usually the most common catheter-related
complications. One example of such technology is impregnation of
the catheter with antimicrobials or antibiotics. But, these
advances do nothing to prevent the injuries explained herein.
[0028] With regard to balloon catheters other than urinary
catheters, such as endotracheal tubes, tracheostomy tubes,
fogarty-type atherectomy balloon catheters, isolation catheters,
angioplasty balloon catheters, valvuloplasty catheters,
vertebroplasty balloons, and other balloons that dilate lumens,
none are provided with any self-regulating or self-deflating safety
features.
[0029] Accordingly, it would be beneficial to provide a balloon
catheter that does not inflate past the tearing limit of a lumen
(e.g., a urethra) and deflates in a desired, predefined way under
certain conditions.
SUMMARY OF THE INVENTION
[0030] It is accordingly a desire to provide an automatically
deflating pressure balloon catheter with a stretch valve and
methods for manufacturing and using the catheter that overcome the
hereinafore-mentioned disadvantages of the heretofore-known devices
and methods of this general type and quickly and rapidly deflates
if pulled out prior to physician-scheduled deflation of the balloon
or that deflates partially if over-inflated.
[0031] With the foregoing and other objects in view, there is
provided, in accordance with the invention, a safety balloon
catheter includes a stretch valve and a balloon catheter having a
proximal catheter end, a balloon defining an interior to be
inflated with an inflation fluid, an inflation lumen extending
through the shaft to the interior and shaped to convey inflation
fluid thereto and from, a second lumen parallel to the inflation
lumen, and a balloon drainage port fluidically connecting the
balloon interior to the second lumen. The hollow stretch valve is
shaped to permit a fluid to pass therethrough and is positioned in
the second lumen to at least partially slide therein such that, in
a steady state, the stretch valve prevents the inflation fluid from
passing through the drainage port and, in an over-inflated state,
the distal sliding portion slides within the second lumen to permit
the inflation fluid to pass through the drainage port and into the
second lumen.
[0032] With the objects of the invention in view, there is also
provided a safety balloon catheter includes a hollow stretch valve
and a flexible, multi-lumen balloon catheter having a proximal
catheter end, a balloon defining a balloon interior to be inflated
with an inflation fluid, a hollow inflation lumen extending through
the shaft to a balloon inflation opening and shaped to convey
inflation fluid to and from the balloon interior, a hollow second
lumen parallel to the inflation lumen, and a balloon drainage port
fluidically connecting the balloon interior to the second lumen.
The hollow stretch valve is shaped to permit a fluid to pass
therethrough and is positioned in the second lumen to at least
partially slide therein such that, in a steady state, the stretch
valve prevents the inflation fluid from passing through the
drainage port and, in an over-pressurized state, the distal sliding
portion slides within the second lumen to permit the inflation
fluid to pass through the drainage port and into the second
lumen.
[0033] With the objects of the invention in view, there is also
provided a safety balloon catheter includes a hollow stretch valve
and a flexible, multi-lumen, balloon catheter having a proximal
catheter end, a balloon having a proximal balloon end and defining
a balloon interior to be inflated with an inflation fluid, a drain
lumen, and a balloon drainage port fluidically connecting the
balloon interior to the drain lumen. The hollow stretch valve is
shaped to permit the given fluid to pass therethrough and is
positioned in the drain lumen to at least partially slide therein
such that, in a steady state, the stretch valve prevents the
inflation fluid from passing through the drainage port and, in a
stretched state when the length between the proximal catheter end
and the proximal balloon end is elongated between approximately 5
percent and approximately 200 percent, the distal sliding portion
slides within the drain lumen to permit the inflation fluid to pass
through the drainage port and into the drain lumen.
[0034] In accordance with another feature of the invention, the
balloon catheter has a shaft outer diameter and the balloon is
inflatable outwardly to a diameter greater than the shaft outer
diameter.
[0035] In accordance with an additional feature of the invention,
the balloon has a distal balloon end and a proximal balloon end and
the over-inflated state occurs when at least one of the distal and
proximal balloon ends is moved in a direction away from the other
of the distal and proximal balloon ends.
[0036] In accordance with yet an added feature of the invention,
the stretch valve is in the over-inflated state when the length
between the proximal and distal balloon ends is elongated between
approximately 5 percent and approximately 200 percent.
[0037] In accordance with yet an additional feature of the
invention, the stretch valve is in the over-inflated state when the
length between the proximal and distal balloon ends is elongated
between approximately 5 percent and approximately 75 percent.
[0038] In accordance with again another feature of the invention,
the balloon has a distal balloon end and a proximal balloon end and
the stretch valve has the over-inflated state when a length between
the proximal catheter end and the proximal balloon end is elongated
between one of approximately 5 percent and approximately 200
percent and approximately 5 percent and approximately 75
percent.
[0039] In accordance with another feature of the invention, the
stretch valve has a distal sliding portion slidably disposed in the
second lumen, a proximal valve end opposite the distal sliding
portion, and a fixed portion fixedly connected within the second
lumen adjacent the proximal valve end.
[0040] In accordance with yet another feature of the invention, the
proximal valve end of the stretch valve is the fixed portion
fixedly connected within the second lumen.
[0041] In accordance with yet a further feature of the invention,
the inflation lumen is fluidically connected to the balloon
interior through at least one inflation port.
[0042] In accordance with yet an added feature of the invention,
the balloon drainage port is a plurality of balloon drainage ports
each fluidically connecting the balloon interior to the second
lumen.
[0043] In accordance with yet an additional feature of the
invention, the drainage port is a plurality of drainage ports each
fluidically connecting at least one of the balloon interior and the
at least one inflation lumen to the second lumen and the stretch
valve, in the steady state, is positioned in the drain lumen to
prevent fluid from passing through the plurality of drainage ports
and, in the over-inflated state, the distal sliding portion slides
within the drain lumen to permit the inflation fluid to pass
through the plurality of drainage ports.
[0044] In accordance with again another feature of the invention,
the balloon has a distal balloon end and the stretch valve is in
the stretched state when the length between the proximal and distal
balloon ends is elongated between approximately 5 percent and
approximately 200 percent.
[0045] In accordance with again a further feature of the invention,
the balloon has a distal balloon end and the stretch valve is in
the stretched state when the length between the proximal and distal
balloon ends is elongated between approximately 5 percent and
approximately 75 percent.
[0046] In accordance with a concomitant feature of the invention,
the stretch valve is in the stretched state when the length between
the proximal catheter end and the proximal balloon end is elongated
between approximately 5 percent and approximately 75 percent.
[0047] The low-pressure balloon catheter of the present invention
prevents injury by having the balloon automatically deflate before
an injury can occur, for example, when being forced to withdraw
from the bladder or being forced to inflate within a urethra.
[0048] The stretch valve balloon catheter of the present invention
prevents injury to patients in various ways. First, the stretch
valve balloon catheter of the present invention prevents injury to
patients by having the balloon automatically deflate before an
injury can occur, for example, when being forced to withdraw from
the bladder prior to physician-scheduled manual deflation. Second,
the stretch valve balloon catheter of the present invention
prevents injury to patients by preventing the balloon from
inflating, for example, when being forced to inflate anywhere
outside the desired location (e.g., the trachea or the urethra). In
the example of a urinary drainage catheter, the stretch valve
balloon catheter of the present invention does not dangerously
inflate when outside the bladder, such as when in the urethra.
Third, the stretch valve balloon catheter of the present invention
prevents injury to the catheter and patient by having the balloon
automatically partially deflate when overinflated, for example,
when a 10 cc balloon is being inflated with 30 cc.
[0049] For placement of this catheter in the bladder in the ideal
position, an exemplary embodiment described herein provides the
physician or technician with a visual aid. In particular, markings
visible from the outside of the catheter are placed to indicate
average or known lengths of the lumen in which it is to be placed
(e.g., the urethra) and they can be different depending on the sex,
weight, or height of the patient.
[0050] While the catheters of the present invention make it a safer
device, e.g., for urinary drainage, the present invention can also
be used for any procedures in which balloons are used to occlude or
distend cavities or lumens. Examples of these procedures include
coronary artery vessels and peripheral vascular vessels, such as
the aorta and extremity vessels. Balloon dilations of other lumens,
such as ureters, bowel, heart valve annulus, prostate and the
esophagus, are also candidates for use of the catheter of the
present invention. Further, the mechanism of pressure release can
be used for any fluid or air-filled device such as tissue
expanders, percutaneous devices, and the like. The inventive
aspects described herein are applicable to all of the various
balloon catheter examples mentioned herein.
[0051] Some of the embodiments of the inventive concepts described
herein utilize a valve (e.g., a slit valve or a stretch valve) that
permits reuse when utilized. Although, when a urinary catheter is
pulled out by a patient, for example, that catheter is typically
discarded for sanitary reasons as exposure outside the treatment
area places the catheter in contact with bacteria that can be
introduced to the patient if reuse occurs. With embodiments having
non-resetting valves, the inventive balloon catheters are single
use after deflation occurs. Although deflation of such a single-use
catheter renders it useless, the act of immediate deflation
protects the patient from serious harm and the cost of replacing a
catheter is minimal as compared to the significant cost of treating
catheter-induced injury. Prevention of such injuries is becoming
more and more important because the injuries are commonplace. The
increase occurs for a number of reasons. First, a greater
percentage of the population is aging. Second, there is a current
trend to use less-skilled health care personnel to perform more
procedures and to be responsible for treatment, both of which save
the hospitals and doctors money. The shortage of nursing
professionals (e.g., R.N.s) exacerbates this trend. The present
tendency is to use nursing professionals for more functions, such
as administration and delivery of medications. This leaves only the
least-skilled technicians with the task of taking vital signs and
inserting catheters. Under such circumstances, more injuries are
likely and do, in fact, occur. Lastly, catheter-related
complications are becoming more severe due to the increased use of
anticoagulation medication, such as PLAVIX.RTM., that is frequently
prescribed in treating cardiovascular disease.
[0052] Yet another possible complication arising from the standard
Foley catheter is that the balloon will not deflate even when the
deflation mechanism is activated. This situation can occur, for
example, because the wrong fluid is used to inflate the balloon or
when a fluid, such as saline, crystallizes, which happens
occasionally. Sometimes, the ability to deflate the balloon is
interrupted because the drainage channel used to deflate the
balloon becomes obstructed, which is common if the catheter is left
in place too long. Remedy of such a scenario involves an invasive
procedure, which includes threading a needle or other sharp object
somewhere through the body cavity to puncture the balloon and,
thus, dislodge the catheter. This procedure is not desirable and is
to be avoided if possible. Yet another possible complication can
occur when the patient has a stricture, i.e., scar tissue in the
urethra that impedes the passage of the catheter. When a technician
is faced with a stricture, it seems to the technician that the
catheter is no longer moving towards the bladder. Consequently, the
technician uses excessive force to push the catheter into the
bladder, thereby causing a tear that creates its own lumen into the
penile and prostatic tissue. As is self-evident, this situation is
accompanied by significant bleeding and the need for additional
corrective procedures and surgery.
[0053] The valved, auto-deflating inventive balloons described
herein further provide a self-regulating feature that prevents
over-inflation of the balloon. Additionally, the valved,
auto-deflating balloons prevent inflation when the balloon is not
placed in an area large enough for complete expansion, e.g., when
the balloon of a urinary Foley catheter is inflated within a
urethra or the balloon of an endotracheal tube is inflated within a
trachea.
[0054] With the low-pressure or valved, auto-deflating balloons
described herein, the technician, nurse, or doctor merely needs to
pull on the catheter to cause the catheter to automatically
deflate, thus sparing the patient from any additional surgical
procedures.
[0055] Added benefits of the catheters described herein do not deal
only with safety, significant financial benefits arise as well. It
is understood that catheter-induced injuries are much more common
than public documentation suggests. Catheter-related trauma occurs
no less that once a week in a large metropolitan hospital. Usually,
each incident not only increases the patient's hospital stay
substantially, but also the expense of the stay. Each incident
(which is usually not reimbursed by insurance) can increase the
cost to the hospital by thousands of dollars, even tens or hundreds
of thousands of dollars. This is especially true when the patient
brings a personal injury action against the hospital, physician(s),
and/or staff. And, when additional surgery is required to repair
the catheter-induced injury, increased expense to the hospital is
not only substantial, if litigation occurs as a result of the
injury, damages awarded to the patient can run into the millions of
dollars. In situations where a safety catheter, such as the ones
described herein, are available but the hospital or physician
decides not to use it and, instead, uses a standard catheter, the
chance that punitive damages are awarded in litigation increases
exponentially. The catheters and methods described herein,
therefore, provide safer catheters that have the possibility of
saving the medical industry billions of dollars.
[0056] To prevent urethra tearing occurrences due to
premature-improper inflation of the balloon and/or due to premature
removal of an inflated balloon, an exemplary embodiment provides
various balloon safety valves. Such valves are configured to
release the inflation liquid from the balloon before injury
occurs.
[0057] The maximum stress that a typical urethra can take without
tearing and/or breaking is known and is referred to as a maximum
urethra pressure. It is also possible to calculate how much
pressure is exerted upon the exterior of a balloon of a balloon
catheter by measuring the pressure required to inflate the balloon.
Knowing these two values, it is possible to construct a balloon
that breaks rapidly and/or ceases inflation if the maximum urethra
pressure is exceeded.
[0058] For example, in a first exemplary embodiment, the balloon,
which is typically some kind of rubber, silicone, elastomer, or
plastic, can be made with a breaking point that instantly deflates
the balloon if the pressure in the balloon exceeds the maximum
urethra pressure. It is acknowledged and accepted that, once the
balloon breaks, this catheter is useless and must be discarded
because the cost of patient injury far outweighs the cost of the
disposable catheter. Also, such a balloon is limited to inflation
with a bio-safe fluid to prevent unwanted air/gas from entering the
patient. If, however, air or other gas will not injure the patient,
the fluid can be air or another gas.
[0059] As an alternative to a one-use breaking safety valve, a
multi-use pressure valve can be added to the balloon inflation
lumen and can be set to open into the drainage lumen if the maximum
urethra pressure is exceeded in the balloon or the balloon
inflation lumen. Such a valve can be located near or at the balloon
inflation port, for example. Any combination of the above
embodiments is envisioned as well.
[0060] Another exemplary embodiment of the present invention
provides the catheter with a balloon that inflates with virtually
no pressure. As used herein, "virtually no pressure,"
"zero-pressure"and "low-pressure" are used interchangeably and are
defined as a range of pressure between approximately standard
atmospheric pressure and 0.3 atmospheres (5 psig). This is in
contrast to "high-pressure," which is greater than approximately
1.5 atmospheres (22 psig). With such a configuration, the
zero-pressure balloon can be deflated with virtually no force. As
such, when the clinician attempts to inflate the zero-pressure
balloon of the present invention within a urethra, the balloon
simply does not inflate. Likewise, when the already inflated
balloon within the bladder is forced into the urethra, such
deflation needs virtually no pressure to collapse the balloon to
fit into the urethra. In both circumstances, injury to the urethra
is entirely prevented.
[0061] Further exemplary embodiments that prevent urethra tearing
occurrences due to premature removal of an inflated balloon or
inflation outside the treatment area provide a balloon catheter
with a stretch valve and methods for manufacturing and using such a
valved catheter. In these variations, the invention takes advantage
of the fact that premature removal of the inflated balloon catheter
requires stretching of the catheter at the proximal side of the
balloon. The valved catheter can be configured with a release
mechanism that is a function of elongation. With short elongations,
the balloon remains inflated. However, when pulled beyond a preset
limit, the valve automatically opens and drains the fluid filling
the balloon. The existence of the stretch valve also provides the
ability to control and eliminate over-inflation. When the balloon
is over-inflated, the ends of the balloon (distal and proximal)
move away from each other. As this movement occurs, the stretch
valve begins to actuate, thereby deflating the balloon until the
proximal and distal ends no longer stretch the balloon. When these
ends are no longer stretched, the valve closes automatically,
thereby preventing further deflation of the previously
over-inflated balloon. The existence of the stretch valve also
provides the ability to control and eliminate inflation when
constricted. For example, when the balloon of the stretch-valve
safety catheter is attempted to be inflated within the confines of
a urethra, in addition to stretching in the radial direction, the
balloon also stretches in the longitudinal direction--the same
direction as the actuation axis of the stretch valve. This
stretching causes the stretch valve to open prior to causing
significant damage to the lumen in which the balloon is being
inflated (e.g., the urethra), thereby directing the inflation fluid
into the drain lumen instead of the balloon.
[0062] In all standard uses of a balloon catheter, the inflation
fluid remains in a closed system. When inflated, the inflation
fluid only enters the inflation lumen and the interior of the
balloon. When so inflated, the inflation fluid never exits the
inflation lumen or the balloon until the health professional or
user specifically deflates the balloon, typically with a syringe
similar to the one that was used to the inflate the balloon in the
first place. The various balloon catheters described herein,
however, do not possess a closed, balloon-inflation system. For the
described low-pressure catheter, the inflation fluid is permitted
to exit out the proximal and/or the distal ends of the balloon into
the environment outside the balloon. For the herein-described
catheters with slit, stretch, or other internal valves, the
inflation fluid is permitted to exit into the drainage lumen, which
is fluidically connected to the external drainage bag and to the
drainage opening at the distal tip of the catheter and, thereby,
the bladder or other expanse in the body. Likewise, for the
herein-described catheters with stretch valves, the inflation fluid
is permitted to exit into the drainage (or inflation) lumen.
[0063] It is known that a technician/physician/user inserting a
balloon catheter does not know where the balloon is placed within
the body after the balloon is inserted therein. It is also known
that approximately 25% of patients who are admitted to a hospital
will have an indwelling catheter at some point during their stay
and 7% of nursing home residents are continually managed by long
term catheterization. Over 4,000,000 indwelling urinary balloon
catheters are inserted in U.S. patients every year and over
25,000,000 are sold in the U.S. every year. Only with radiographic
or sonographic equipment can the balloon portion of the catheter be
visualized within the body. This type of visualization is simply
too expensive to use every time, for example, a urinary catheter is
used.
[0064] The difference from standard closed-system balloon catheters
of the herein-described safety catheters provides unique benefits
not found elsewhere or before. More specifically, only with the
inventive safety catheters described herein does the inflation
fluid have the opportunity to exit the balloon. When the inflation
fluid exits the balloon of these safety catheters, it provides a
unique and automatic way of informing the user or health-care
professional that a dangerous condition has just been prevented.
More specifically, if the inflation fluid contains an inert
colorant that is different from any color of fluid that typically
is drained by the balloon catheter, the herein-described safety
catheters will show, visually and immediately, either that an
attempt has been made to inflate the balloon within a constricted
lumen (such as the urethra) or that the catheter has been stretched
enough to cause the stretch-valve of the inserted balloon to act
and prevent possible pull-out injury. In the former case, if the
balloon is attempted to be inflated within a constricted lumen
(e.g., urethra) and not in the larger treatment area (e.g.,
bladder), then the inflation fluid will, upon the attempted
inflation, be almost immediately apparent to the user/health-care
professional when it drains directly into the drainage bag. When
the user/health-care professional sees the color in the drainage
bag, he/she knows that the balloon is not correctly placed and
corrective action can be taken immediately and before injury or
further injury occurs. In the latter case, if the catheter is
pulled by the patient or by catching the environment, and the
catheter is not completely removed from the patient, at least some
or all of the inflation fluid will drain into the drainage bag.
When that bag is next inspected by the user/health-care
professional, it will be immediately apparent that something is
wrong and that the catheter needs examination and/or removal and
replacement. Some variations herein allow the balloon to even be
refilled if deflation occurs without any injury and if the catheter
is not pulled out sufficiently far to require replacement. In any
case, injury is prevented.
[0065] The invention is not limited to this visual aid for
indicating to a physician, nurse, or technician that the catheter
has been installed improperly. For male and female patients, it is
known approximately how far the catheter needs to be inserted into
the urethra because average urethra lengths for males and females
are known. With this information, the catheter described herein can
be provided with external markings indicating those average urethra
lengths. Even if the catheters are not male or female specific,
both indications can be provided on a given catheter. In this way,
if, after believing that insertion is "correct," the user still
sees the marking outside the patient, the user can double check the
insertion before inflating the balloon (which would occur within
the urethra if not installed far enough therein). Additionally,
these markings can provide immediate visual indications to medical
personnel when it is not known that a patient has jerked out the
catheter partially or the catheter snagged on the environment and
was pulled out partially. In either situation, if the medical
personnel looks at the catheter and sees the markings, then it
becomes immediately clear that the inflated balloon catheter has
been improperly removed, but partially, and immediate corrective
action can be taken.
[0066] Description of one exemplary embodiment herein in a way that
separate from other exemplary embodiments is not to be construed
mean that the one embodiment mutually exclusive of the other
exemplary embodiments. The various exemplary embodiments of the
safety catheters mentioned herein can be used separately and
individually or they can be used together in any combination.
[0067] Although some variations are illustrated and described
herein as embodied in a stretch valve balloon catheter and methods
for producing and using such a catheter, they are, nevertheless,
not intended to be limited to the details shown because various
modifications and structural changes may be made therein without
departing from the spirit of the invention and within the scope and
range of equivalents of the claims. Additionally, well-known
elements of exemplary embodiments of the invention will not be
described in detail or will be omitted so as not to obscure the
relevant details of the invention.
[0068] Other features that are considered as characteristic for the
invention are set forth in the appended claims. As required,
detailed embodiments of the present invention are disclosed herein;
however, it is to be understood that the disclosed embodiments are
merely exemplary of the invention, which can be embodied in various
forms. Therefore, specific structural and functional details
disclosed herein are not to be interpreted as limiting, but merely
as a basis for the claims and as a representative basis for
teaching one of ordinary skill in the art to variously employ the
present invention in virtually any appropriately detailed
structure. Further, the terms and phrases used herein are not
intended to be limiting; but rather, to provide an understandable
description of the invention. While the specification concludes
with claims defining the features of the invention that are
regarded as novel, it is believed that the invention will be better
understood from a consideration of the following description in
conjunction with the drawing figures, in which like reference
numerals are carried forward. The figures of the drawings are not
drawn to scale.
[0069] Before further disclosure and description, it is to be
understood that the terminology used herein is for the purpose of
describing particular embodiments only and is not intended to be
limiting. The terms "a" or "an", as used herein, are defined as one
or more than one. The term "plurality," as used herein, is defined
as two or more than two. The term "another," as used herein, is
defined as at least a second or more. The terms "including" and/or
"having," as used herein, are defined as comprising (i.e., open
language). The term "coupled," as used herein, is defined as
connected, although not necessarily directly, and not necessarily
mechanically.
[0070] As used herein, the term "about" or "approximately" applies
to all numeric values, whether or not explicitly indicated. These
terms generally refer to a range of numbers that one of skill in
the art would consider equivalent to the recited values (i.e.,
having the same function or result). In many instances these terms
may include numbers that are rounded to the nearest significant
figure. In this document, the term "longitudinal" should be
understood to mean in a direction corresponding to an elongated
direction of the catheter. Lastly, the term "proximal" refers to
the end of the catheter closest to the person inserting the
catheter and is usually that end of the catheter with a hub. The
distal end of the catheter is the end furthest away from the person
inserting the catheter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0071] In the following, the invention will be described in more
detail by exemplary embodiments and the corresponding figures. By
schematic illustrations that are not true to scale, the figures
show different exemplary embodiments of the invention.
[0072] FIG. 1 is a diagrammatic, fragmentary, longitudinal
cross-sectional view of a prior art catheter ideally placed in a
urethra and a bladder of a male patient;
[0073] FIG. 2 is a fragmentary, enlarged, longitudinal
cross-sectional view of a distal portion of a first embodiment of a
pressure-limiting balloon catheter according to the invention;
[0074] FIG. 3 is a fragmentary, enlarged longitudinal
cross-sectional view of a proximal portion of a second embodiment
of a pressure-limiting balloon catheter according to the
invention;
[0075] FIG. 4 is a fragmentary, enlarged, cross-sectional view of a
first alternative configuration of the safety valve of FIG. 3;
[0076] FIG. 5 is a fragmentary, enlarged, cross-sectional view of a
second alternative configuration of the safety valve of FIG. 3;
[0077] FIG. 6 is a fragmentary, enlarged, cross-sectional view of a
third alternative configuration of the safety valve of FIG. 3;
[0078] FIG. 7 is a fragmentary, further enlarged, cross-sectional
view of the safety valve of FIG. 6;
[0079] FIG. 8 is a fragmentary, further enlarged, cross-sectional
view of a fourth alternative configuration of the safety valve of
FIG. 3;
[0080] FIG. 9 is a fragmentary, partially hidden, perspective view
of an exemplary embodiment of a zero-pressure safety catheter
according to the invention;
[0081] FIG. 10 is a radial cross-sectional view of a portion of the
catheter of FIG. 9 at section line 10-10;
[0082] FIG. 11 is a process flow diagram of an exemplary method of
forming a zero-pressure balloon according to the invention;
[0083] FIG. 12 is a process flow diagram of an exemplary method of
attaching a zero-pressure balloon according to the invention;
[0084] FIG. 13 is a fragmentary, enlarged, perspective view of a
distal portion of an exemplary embodiment of a zero-pressure
catheter according to the invention;
[0085] FIG. 14 is a radial cross-sectional view of a slit-valve
portion of the catheter of FIG. 13 at section line 14-14;
[0086] FIG. 15 is a radial cross-sectional view of an alternative
embodiment of a slit-valve portion of the catheter of FIG. 13 at
section line 15-15;
[0087] FIG. 16 is a fragmentary, enlarged, partially
cross-sectional and partially perspective view of an everting
balloon catheter according to the invention in a correctly inserted
position in the bladder;
[0088] FIG. 17 is a fragmentary, enlarged, partially
cross-sectional and partially perspective view of the catheter of
FIG. 16 being pulled distally out of the bladder and beginning its
everting deflation;
[0089] FIG. 18 is a fragmentary, enlarged, partially
cross-sectional view of the catheter of FIG. 16 with the everting
deflation complete;
[0090] FIG. 19 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of a prior art urinary
catheter in an uninflated state;
[0091] FIG. 20 is a fragmentary, enlarged, longitudinal
cross-sectional view of the prior art urinary catheter of FIG. 19
in an inflated state within a bladder;
[0092] FIG. 21 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of an exemplary
embodiment of an automatically deflating, stretch valve urinary
balloon catheter according to the invention with the balloon in an
uninflated state;
[0093] FIG. 22 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 21 with the balloon in an inflated
state and with the stretch valve in an unactuated state;
[0094] FIG. 23 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 21 with the balloon in an inflated
state and with the stretch valve in an actuated state;
[0095] FIG. 24 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of another exemplary
embodiment of an automatically deflating, stretch valve urinary
balloon catheter according to the invention with the balloon in an
uninflated state;
[0096] FIG. 25 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 24 with the balloon in an inflated
state and with the stretch valve in an unactuated state;
[0097] FIG. 26 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 24 with the balloon in an inflated
state and with the stretch valve in an actuated state;
[0098] FIG. 27 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of still another
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in an uninflated state;
[0099] FIG. 28 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 27 with the balloon in an inflated
state and with the stretch valve in an unactuated state;
[0100] FIG. 29 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 27 with the balloon in an inflated
state and with the stretch valve in an actuated state;
[0101] FIG. 30 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 27;
[0102] FIG. 31 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 27 turned ninety degrees
counterclockwise when viewed from a proximal end thereof and with
the stretch valve in an unactuated state;
[0103] FIG. 32 is a fragmentary, enlarged, longitudinal
cross-sectional view of the automatically deflating, stretch valve
urinary balloon catheter of FIG. 27 turned ninety degrees
counterclockwise when viewed from a proximal end thereof and with
the stretch valve in an actuated state;
[0104] FIG. 33 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of yet another exemplary
embodiment of an automatically deflating, stretch valve urinary
balloon catheter according to the invention with the balloon in a
partially inflated state and the stretch valve in an unactuated
state;
[0105] FIG. 34 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of yet a further
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in a partially inflated state and the stretch valve in an
unactuated state
[0106] FIG. 35 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of still a further
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in a partially inflated state and the stretch valve in an
unactuated state;
[0107] FIG. 36 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of an additional
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in a partially inflated state and the stretch valve in an
unactuated state;
[0108] FIG. 37 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of another exemplary
embodiment of an automatically deflating, stretch valve urinary
balloon catheter according to the invention with the balloon in a
partially inflated state and the stretch valve in an unactuated
state;
[0109] FIG. 38 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of still another
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in a partially inflated state and the stretch valve in an
unactuated state;
[0110] FIG. 39 is a flow chart of exemplary embodiments of
processes for making a catheter according to the invention;
[0111] FIG. 40 is a flow chart of exemplary embodiments of other
processes for making a catheter according to the invention;
[0112] FIG. 41 is a flow chart of exemplary embodiments of further
processes for making a catheter according to the invention;
[0113] FIG. 42 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of another exemplary
embodiment of an automatically deflating, stretch valve urinary
balloon catheter according to the invention with the balloon in a
partially inflated state and the stretch valve in an unactuated
state;
[0114] FIG. 43 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of still another
exemplary embodiment of an automatically deflating, stretch valve
urinary balloon catheter according to the invention with the
balloon in a partially inflated state and a longer stretch valve in
an unactuated state;
[0115] FIG. 44 is an enlarged, perspective view of an exemplary
embodiment of a stretch valve for a urinary balloon catheter
according to the invention;
[0116] FIG. 45 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of an automatically
deflating, stretch valve urinary balloon catheter with the stretch
valve of FIG. 44 in an unactuated state and with the balloon in a
partially inflated state;
[0117] FIG. 46 is an enlarged, perspective view of another
exemplary embodiment of a stretch valve for a urinary balloon
catheter according to the invention;
[0118] FIG. 47 is a fragmentary, enlarged, longitudinal
cross-sectional view of a balloon portion of an automatically
deflating, stretch valve urinary balloon catheter with the stretch
valve of FIG. 46 in an unactuated state and with the balloon in a
partially inflated state;
[0119] FIG. 48 is a fragmentary, enlarged, longitudinal
cross-sectional view of a stretching portion of an automatically
deflating, stretch valve balloon catheter with the proximal end of
the stretch-valve tube gripped within a drainage lumen; and
[0120] FIG. 49 is an enlarged, longitudinal cross-sectional view of
an exemplary embodiment of a stretch-valve tube.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0121] While the specification concludes with claims defining the
features of the invention that are regarded as novel, it is
believed that the invention will be better understood from a
consideration of the following description in conjunction with the
drawing figures, in which like reference numerals are carried
forward.
[0122] Herein various embodiment of the present invention are
described. In many of the different embodiments, features are
similar. Therefore, to avoid redundancy, repetitive description of
these similar features may not be made in some circumstances. It
shall be understood, however, that description of a first-appearing
feature applies to the later described similar feature and each
respective description, therefore, is to be incorporated therein
without such repetition.
[0123] Referring now to the figures of the drawings in detail and
first, particularly to FIG. 2 thereof, there is shown a first
embodiment of a pressure-limiting balloon catheter 100 that does
not inflate past the tearing limit of a lumen in which the catheter
100 is placed, for example, in the urethra.
[0124] To prevent occurrences of urethra tearing due to
premature-improper inflation of the balloon and/or due to premature
removal of an inflated balloon, the invention of the instant
application provides the balloon 110 with a balloon safety valve
112. As set forth above, in a balloon 3 of a conventional catheter
(see reference numerals 1 to 5 in FIG. 1), the high-pressure
balloon 3 is fixed to the outer surface of the fluid drainage lumen
120 (not shown in FIG. 1) and is not intended to be removed
therefrom or to burst thereon unless an extraordinary amount of
inflation occurs. Such a tearing event is not supposed to occur
under any circumstances during use with a patient. If such an event
happens, the material of the balloon 3 will open at a random
location, based upon the microscopic fractures or weaknesses in the
material itself, and risk serious damage to the patient associated
with the bursting, as well as a risk of balloon fragmentation,
which could leave one or more pieces of the balloon 3 inside the
patient after removal of the catheter 1.
[0125] In contrast to such conventional devices, the balloon 110 of
the present invention is created specifically to tear when a
predefined pressure exists in or is exerted on the balloon 110. The
controlled tear will occur because the balloon safety valve 112 is
present. Conventional balloons have constant balloon wall
thicknesses (before inflation). In contrast thereto, the balloon
safety valve 112 in the first embodiment is a defined reduction in
balloon wall thickness. This reduction creates a breaking point or
selected breaking points at which the balloon 110 is intended
specifically to break when a predefined force exists in or is
imparted on the balloon 110. Because the balloon 110 is made of a
material having a known tearing constant--dependent upon the
thickness thereof (which is determined experimentally for different
thicknesses of a given material prior to use in a patient), the
balloon safety valve 112 of the present invention for urethra
applications is matched to break when the pressure inside or
exerted on the balloon 110 approaches the maximum urethra
pressure.
[0126] In the embodiment shown in FIG. 2, a decreased thickness is
formed as a first semi-circumferential groove 114 near a proximal
end of the balloon 110 and/or as a second semi-circumferential
groove 116 near a distal end of the balloon 110. The grooves 114,
116 can have any cross-sectional shape, including, trapezoidal,
triangular, square, or rectangle, for example. Because rubber,
plastic, and silicone materials tear well with thinner cuts, a
relatively triangular shape or one with a narrow bottom can be an
exemplary configuration. To make sure that the entire balloon 110
of the illustrated embodiment does not completely tear away from
the fluid drainage lumen 120, both grooves 114, 116 do not extend
around the entire circumference of the balloon 110. As shown to the
left of the proximal groove 116 in FIG. 2, the groove 116 is not
present on at least an arc portion 118 of the circumference of the
balloon 110. The arc portion is defined to be sufficiently large so
that, when the catheter 100 is removed from the patient, the
balloon 110 cannot tear away entirely from the catheter 100 (and
create the disadvantageous fragmentation situation as set forth
above). The illustrated balloon safety valve 112 is, therefore,
fashioned to keep the balloon 110 in one piece after breaking and
remain firmly connected to the catheter 100 to insure that no piece
of the balloon 110 will be left inside the patient after actuation
of the balloon safety valve 112. Alternatively, the groove can be
along the length of the balloon parallel to the axis of the
catheter. This groove can be made by skiving the balloon after
attaching to the catheter or by skiving the balloon as it is formed
during extrusion or dip molding. In this embodiment, when the
pressure exceeds a predetermined limit, the balloon splits along
the groove without releasing fragments.
[0127] It is noted that the balloon 110 is inflated through an
inflation lumen 130 having a proximal opening, typically formed by
one end of a luer connector (see 260 in FIG. 3). The illustrated
end is connected to a non-illustrated inflation device, for
example, a distal end of a syringe for inflation of the balloon
110.
[0128] In this first embodiment, the balloon can be of an
elastomer, rubber, silicone, or plastic, for example. Once the
balloon breaks, the catheter is useless and must be discarded.
Because the balloon 110 in this embodiment will break inside the
patient, it should be inflated with a bio-safe fluid to prevent
unwanted air, gas, or bio-unsafe fluid from entering the patient.
In certain circumstances where balloon catheters are used, air or
gas will not injure the patient if let out into the patient's body
cavity. In such circumstances, the inflating fluid can be air under
pressure, for example.
[0129] Maximum urethra pressure can also be tailored to the
individual patient. Based upon a urethral pressure-measuring
device, the patient's maximum urethra pressure can be measured
before the catheter 100 is placed therein. A set of catheters 100
having different safety valve breaking constants can be available
to the physician and, after estimating or calculating or knowing
the patient's maximum urethra pressure, the physician can select
the catheter 100 having a safety valve breaking constant slightly
or substantially smaller than the patient's maximum urethra
pressure. Accordingly, if the pressure in the balloon 110
approaches the patient's maximum urethra pressure for any reason,
whether it is due to over-inflation, improper placement, and/or
premature removal, the balloon 110 is guaranteed to break prior to
the patient's lumen (in particular, the patient's urethra) and,
therefore, prior to causing injury.
[0130] A second embodiment of the one-use breaking safety valve of
a pressure-limiting balloon catheter 200 is shown in FIG. 3. The
catheter 200 has a fluid drainage lumen 220, a balloon inflation
lumen 230, and a secondary lumen 240.
[0131] The fluid drainage lumen 220 is connected fluidically to the
body cavity (i.e., the bladder 30) for draining fluid from the body
cavity.
[0132] The secondary lumen 240 can be used for any purpose, for
example, for housing the radiation line that will supply energy to
the radiation coil 2. It can also be used for injecting fluid into
any distal part of the catheter 200 or even the body cavity
itself.
[0133] The balloon inflation lumen 230 begins at a proximal end
with an inflating connector 260 that, in an exemplary embodiment,
is one part of a luer connector. The balloon inflation lumen 230
continues through the body of the catheter 200 all the way to the
balloon 110 and is fluidically connected to the interior of the
balloon 110.
[0134] Alternatively or additionally, the balloon safety valve is
fluidically connected to the balloon inflation lumen 230. In a
second embodiment of the safety valve 212, the valve 212 is formed
integrally with the balloon inflation lumen 230 and is set to open
into the environment (instead of into the patient) if the maximum
urethra pressure is exceeded in the balloon 110 or the balloon
inflation lumen 230. Alternatively and not illustrated, the valve
212 is formed integrally with the balloon inflation lumen 230 and
is set to open into the drainage lumen 220 if the maximum urethra
pressure is exceeded in the balloon 110 or the balloon inflation
lumen 230. A further alternative includes opening both into the
environment and into the drainage lumen 220. Because this safety
valve 212 is located near or at the balloon inflation port 260 in
this configuration, fluid used to inflate the balloon will not
enter the patient when the valve 212 opens.
[0135] The safety valve 212 in the second embodiment can merely be
a narrowing of the distance between the balloon inflation lumen 230
and the outer surface 250 of the catheter 220. In FIG. 3, the valve
212 has a rectangular cross-section and extends away from the
balloon inflation lumen 230. As shown in FIGS. 4, 5, and 6,
respectively, the cross-section can be triangular (peaked or
pyramidical in three-dimensions), curved (circular or cylindrical
in three-dimensions), or trapezoidal (frusto-conical or bar-shaped
in three-dimensions). The cross-sections are shown in FIGS. 3 to 7
with the narrowing emanating from the balloon inflation lumen 230
outward. As an alternative, the narrowing can begin on the outer
surface of the catheter and extend inwards towards the balloon
inflation lumen 230. A further alternative can have the narrowing
extend from both the inner lumen 230 and the outer surface of the
catheter.
[0136] The cross-sections illustrated are merely exemplary. What is
important is that the thickness t between the bottom 213 of the
valve 212 and the outer surface 250 of the catheter 220 in
comparison to the thickness T of the catheter body over the
remainder of the balloon inflation lumen 230. An enlarged view of
this thickness comparison is illustrated in FIG. 7. As long as the
thickness t is smaller than the thickness T (t<T), and as long
as the force F.sub.b required to break the balloon is greater than
the force F.sub.sv required to break the portion 213 of the safety
valve 212 (F.sub.b>F.sub.sv), then the portion 213 of the safety
valve 212 is virtually guaranteed to break every time pressure
exerting a force F in the balloon inflation lumen 230 is greater
than the force F.sub.sv required to break the safety valve
(F.sub.sv>F).
[0137] Based upon this analysis, the force F.sub.sv required to
break the safety valve can be tuned to whatever a patient needs or
a physician desires and different sized valves can be available for
any procedure and provided in the form of a kit. Whether a standard
maximum urethra pressure is used or a patient-specific maximum
urethra pressure is measured and used, experiments can be conducted
prior to use on a patient on various catheter thicknesses t to
determine the pressure needed to break the portion 213 of the
safety valve 212. For example, ten different maximum urethra
pressures can be known as desirable set points and the thicknesses
t can be varied such that pressure required to break the ten
thicknesses correspond to the ten set point pressures. If, then,
ten catheters are placed in such a kit, each having one of the ten
thicknesses, then the physician has a range of 10 maximum urethra
pressure values to use with the patient.
[0138] Although FIGS. 3 to 7 show indentations into the wall of the
catheter, the indentation can be in the form of a through-hole
entirely through the wall of the catheter communicating with the
outside of the catheter over which is placed a sleeve. Depending
upon the pressure in the inflation lumen, fluid can leak through
the hole and lift up the sleeve and leak to atmosphere therefrom.
Pressure is controlled in this embodiment by the modulus of the
sleeve material. A harder sleeve that fits snugly on the catheter
will not allow leakage at low pressure. Alternatively, a softer
rubbery sleeve would lift up easily to release high pressure
fluid.
[0139] The safety valve 212 of the second embodiment need not be
confined to the body of the catheter 200. Instead, the inflating
connector 260 can, itself, be equipped with the pressure relief
valve 212. Alternatively, a non-illustrated modular attachment
containing the safety valve 212 can be attached to the inflating
connector 260. Such a modular valve attachment is removable and
replaceable (such as through a conventional luer or even a
screw-threaded connection). Accordingly, as long as the catheter
200 can still be used after the valve 212 actuates (breaks), the
used modular valve attachment can be replaced with a new
attachment. The converse is also true for reuse of the attachment
if the catheter 200 breaks and the valve of the attachment remains
unbroken. A downstream end of the modular valve attachment (e.g.,
shaped as part of a luer connector) is attached removably to an
upstream end of the inflating connector 260 and the upstream end of
the modular valve attachment is to be connected to the balloon
inflation device, which is commonly a syringe. The upstream end of
the modular valve attachment is, likewise, part of a luer connector
for easy connection to standard medical devices. In such a
configuration, the safety valve 212, 312 of the present invention
can be entirely separate from the catheter 200, 300 and, therefore,
form a retrofitting device for attachment to any luer connector
part present on conventional catheters.
[0140] As an alternative to the one-use breaking safety valve of
the second embodiment, a multi-use pressure valve can be used. This
third embodiment of the pressure-limiting balloon catheter 300 is
illustrated in FIG. 8. The catheter 300 can be the same as the
catheter 200 in FIG. 3 except for the portion illustrated in FIG.
8. Instead of having a narrowing thickness t of the lumen wall, the
valve portion 313 extends entirely to the environment (and/or into
the drainage lumen 220). However, a one-way valve 314 (shown only
diagrammatically in FIG. 8) is attached to the open end of the
valve portion 313 and is secured to the outer surface 250 of the
catheter 300 to close off the open end of the valve portion 313.
The one-way valve 314 can be secured directly to the outer surface
250 (e.g., with an adhesive), or a connector 315 (e.g., a threaded
cap) can secure the one-way valve 314 to the open end of the valve
portion 313. Regardless of the configuration, the one-way valve 314
includes a device that does not permit fluid from exiting the lumen
230 until a given resistance R is overcome. This given resistance R
can be selectable by the physician depending upon the one-way valve
that is chosen for use if a set of one-way valves having different
resistances R are available for use by the physician. Just like the
second embodiment, the resistance R can be set to correspond to
desired maximum urethra pressure values. Therefore, when used, the
fluid exits the one-way valve 314 into the environment well before
the patient's maximum urethra pressure is exceeded by the
balloon.
[0141] The one-way valve 314 can be a mechanical one-way valve.
Additionally, the one-way valve 314 can be a material having a tear
strength corresponding to a desired set of resistances R. The
material can be a fluid-tight fabric, a rubber, a plastic, or
silicone different from the material making up the catheter. The
material can even be a rubber, plastic, or silicone the same as the
material making up the catheter but having a reduced thickness t
than the thickness T of the catheter. Alternatively, the one-way
valve 314 can be a slit valve. Various exemplary embodiments of
such a valve can be found in U.S. Pat. No. 4,995,863 to Nichols et
al., which is hereby incorporated herein by reference in its
entirety.
[0142] It can also be appreciated that the pressure release (or
relief) valve can be a conventional pressure release valve
comprised of a housing with a lumen, a ball, and a spring within
the lumen wherein the spring presses the ball against a defined
opening. When pressure on the ball exceeds the force of the spring,
the ball moves away from the defined opening and fluid moves around
the ball and vents to atmosphere. By controlling tension on the
spring, the pressure at which the valve releases pressure can be
controlled. It can also be appreciated that the pressure release
valve can be coupled to a luer connector, which can be coupled to a
one-way check valve that can be used to inflate the balloon as is
often used in conventional urinary drainage catheters.
[0143] Because the safety valve 212, 312 is located at the proximal
end of the catheter 200, 300, the distal end of the catheter 200,
300 can take the form of a distal end of a conventional balloon
catheter 2, 3, 4, 5. Alternatively, the distal end shown in FIG. 2
can also be used for redundant over-pressure protection.
[0144] In another exemplary embodiment of the present invention,
FIGS. 9 to 18 illustrate alternatives to the elastomeric balloon
described above. In particular, the above elastomeric balloon is
replaced by a thin walled, pre-formed, fixed diameter balloon 1010
that inflates with virtually no pressure and withstands pressures
between approximately 0.2 atmospheres (2.9 psi) and 0.5 atmospheres
(7.35 psi), the latter of which is approximately equal to the
maximum urethra pressure, without an appreciable increase in
diameter. Examples of such balloon materials and thicknesses are
used in the medical field already, such as those used in
angioplasty. Other exemplary materials can be those used in
commercial (party) balloons, for example, MYLAR.RTM., or similar
materials such as nylon, PTA, PTFE, polyethylene and polyurethane,
for example. In FIGS. 9 and 13, the balloon 1010 is shown in a
spherical shape. However, the balloon 1010 can be, for example,
cylindrical with flat or conically tapering ends.
[0145] The inflation balloon 1010 can be formed by heating a
tubular material within a mold or by heat-sealing thin sheets to
one another (e.g., party balloons have two sheets). One example of
the relatively non-compliant, thin-walled balloon 1010 of the
present invention is formed using a blow-molding process. In the
blow-molding process, a thermoplastic material such as nylon,
polyurethane, or polycarbonate is extruded or formed into a hollow,
tube-like shape (parison) and is subsequently heated and
pressurized, usually with air, inside a hollow mold having a shape
to form the final outer dimensions of the balloon. An example of
the blow molded product is the common plastic soda or water bottle
containers.
[0146] One exemplary, but not limiting, process to form the
zero-pressure balloon of the present invention is described with
respect to FIG. 11 and includes, in Step 1110, cutting a relatively
short piece of "parison" tubing that is formed using standard
"air-mandrel" extrusion techniques. In Step 1120, one end of the
tubing is sealed. The center portion of the tubing is placed in a
hollow mold, leaving both ends extending outside of the mold in
Step 1130. The center of the tubing is heated in Step 1140 with a
hot stream of air through a small hole in the center of the mold
for a few seconds to soften the tubing walls within the mold. The
inside of the tubing is pressurized with a fluid, e.g., air, in
Step 1150 to stretch the tubing walls to conform to the inside
dimensions of the mold. After a short cooling period, an additional
stretch of the formed balloon is done in Step 1160 by pulling on
the (external) parison and, after a second "blowing" in the same
mold in Step 1170, is used to create a very thin-walled balloon
(much less than 0.001 inches, typically, based upon the parison
wall thickness and the final balloon diameter). The extra (unblown)
parison tubing is then cut off from both ends in Step 1180, leaving
the thin walled, relatively supple balloon and its "legs" to be
mounted to the catheter as described below.
[0147] This exemplary process can be used to create thin,
non-compliant balloons for "angioplasty" of blood vessels at
pressures exceeding 12 atmospheres of pressure, for example.
Although these pressures are not necessary in the present
application, it is witness to the fact that very strong thin-walled
balloons can result from the above manufacturing process.
[0148] The present invention's thin, non-compliant zero-pressure
balloon can be attached to the drainage catheter in a number of
ways. In a first exemplary attachment embodiment, reference is made
to the process of FIG. 12, the slit valve of FIG. 13, and the
removable balloon of FIG. 16.
[0149] In an exemplary embodiment, each of the distal and proximal
legs of the balloon 1010 manufactured according to the process of
FIG. 12 is attached to the distal end of the drainage catheter
using standard (e.g., FDA-approved) cements or by heat fusing the
two pieces together. The non-compliant, thin-walled balloon is
dimensioned to envelop the "slit valves" shown, for example, in
FIG. 13, as an exemplary configuration of the invention. The
balloon's thin walls allow folding of the balloon without a
significant increase in the catheter outer diameter for ease in
catheter insertion.
[0150] Exemplary embodiments of the internal balloon valve 1012
according to the invention are illustrated in FIGS. 13, 14, and 15.
This internal balloon valve 1012 is formed by cutting the wall of
the drainage lumen 1120 at the portion of the catheter shaft 1020
within the balloon 1010. The slit can be a single cut or a
plurality of cuts. Some exemplary slit valves other than those
shown are described in U.S. Pat. No. 4,995,863 to Nichols et al.,
all of which can be utilized for the present invention. The
slit-opening pressure, therefore, can be regulated by adjusting the
number, length and spacing of the slit(s) and the thickness of the
drainage lumen wall 1122. For example, the length and orientation
of the slit(s) 1012 determines the pressure at which it/they will
open and drain the balloon inflation lumen 1130. In one particular
embodiment shown in FIG. 15, the slits 1124 are cut through the
elastomeric walls in a way that results in a wedge-shaped
cross-section. With this wedge shape, fluid within the balloon can
drain under pressure easily. The wedge can be increasing or
decreasing. With the former, the edges are chamfered towards one
another from the central axis of the balloon toward the exterior
thereof (e.g., illustrated in FIG. 15) and, with the latter, the
edges are chamfered towards one another from the exterior of the
balloon toward the central axis.
[0151] In another exemplary embodiment, a non-illustrated,
thin-walled slitted sleeve can be disposed over the portion of the
drainage catheter wall 1122 within the balloon 1010 and covering a
throughbore fluidically connecting the interior of the balloon 1010
to the interior of the drainage lumen 1120. As such, pressure
within the balloon 1010 will open the slit(s) of the sleeve,
thereby fluidically connecting the balloon 1010 interior with the
drainage lumen 1120 to transfer fluid in the balloon 1010 to the
drainage lumen 1120. Each of these exemplary balloon configurations
entirely prevents damage caused by improper inflation or premature
removal.
[0152] Alternatively, the balloon wall itself could be modified to
burst at a particular pressure to release the inflation media. This
weakened section could be created by mechanical, chemical, or
thermal treatment for example. Mechanical measures may be
accomplished by scratching the surface and, thus, thinning the
balloon wall in a particular section to cause it to burst at a
pre-determined pressure or actually slicing or punching a hole in
the wall and covering the area with a thinner, weaker film of
material which will tear at a predetermined pressure lower than the
rest of the balloon. Likewise, a chemical solvent could be applied
to create the same effect as the mechanical device above by making
chemical changes to the plastic molecular structure of the balloon
wall and, thereby, weakening a desired section of the balloon wall.
Weakening a section of the wall by heat to thereby re-orient its
molecular structure (much like softening by annealing) is also
possible. Therefore, the preferential tearing of the balloon wall
at a predetermined internal pressure can be effected in a number of
ways as exemplified by, but not limited to, the methods described
above.
[0153] A second exemplary, but not limiting, process to attach the
zero-pressure balloon of the present invention to the safety
catheter 1600 of the present invention, which can be used with or
without the slit valves, is described with respect to FIGS. 12 and
16 and includes, in Step 1210, assembling a first proximal leg 1620
of the balloon 1610 over the distal end of the drainage catheter
shaft 1630 in an "inverted" direction (open end toward the balloon
interior as shown in FIG. 16). This inverted connection is
accomplished with a mechanical release that can be formed, for
example, merely by using the shape of the proximal leg 1620 of the
balloon 1610 or by using a separate compression device, such as an
elastic band, or by using adhesives that removably connect the
proximal leg 1620 to the drainage catheter shaft 1630. In a
compression only example, the proximal balloon seal is, thereby,
formed by the force of the "inverted" relatively non-compliant
proximal leg 1620 being extended over and around the distal end of
the flexible drainage catheter shaft 1630 by, for example,
stretching the material of the drainage catheter shaft 1630 (e.g.,
silicone) to reduce its outer diameter. The other, distal leg 1640
of the balloon 1610 can, then, be attached in Step 1220 using
cements (as in the first example above) or by heat fusion. It is
noted that, while attachment is shown and described in an inverted
orientation for the proximal leg 1620 and in a non-inverted
orientation for the distal leg 1640, these are not the only
possible orientations for each and can be assembled in any
combination of inverted and non-inverted orientations. For example,
the distal leg 1640 can, as the proximal leg 1620, be attached in
an inverted direction not illustrated in FIG. 16.
[0154] To further aid in balloon assembly and catheter deflation
and insertion, the outer diameter of the catheter 1600 under the
balloon 1610, as well as the inner diameter of the distal balloon
leg 1640, can be reduced as compared with the outer diameter of the
drainage catheter shaft 1630, which configuration is shown in FIGS.
16 to 19. The reduced-diameter portion of the catheter 1600 is
referred herein as the distal tip portion 1650 and extends from the
distal end of the drainage catheter shaft 1630 at least to the
distal end of the distal balloon leg 1640. As shown, the distal tip
5 (distal of the balloon 1610) also can have the same reduced
diameter (or can be reduced further or increased larger as
desired). Thus, if the outer diameter of the distal tip portion
1650 is reduced immediately distal of the proximal balloon seal
1620, any predetermined pull force will stretch the catheter shaft
1630, thereby reducing the outer diameter of the catheter shaft
1630 at the proximal balloon seal and allowing the proximal balloon
leg 1620 to slide or peel distally and deflate the balloon quickly,
at which time all fluid is released therefrom into the bladder or
urethra, for example. It is envisioned that the proximal balloon
leg 1620 can be mounted with the balloon leg 1620 in a non-inverted
or "straight" position if desired with similar results. However, in
such a configuration, sliding of the proximal leg 1620 over the
distal end of the catheter shaft 1630 may be more resistant to a
pulling force on the exposed proximal end of the catheter shaft
1630 but the slight incursion of the balloon-filling fluid can be
used to lubricate this connection and, therefore, the resistance to
pulling decreases.
[0155] With a zero-pressure configuration as described and referred
to herein, the balloon 1010, 1610 is under zero-pressure or low
pressure. Thus, the inflation device (e.g., a syringe) need not be
configured to deliver pressure much above the low pressure range
described above. Mere presence of the filling liquid in the
balloon, makes the balloon large enough to resist and prevent
movement of the balloon into the urethra and out of the bladder
without having an internal, high pressure. As such, when inserted
improperly in the urethra, the balloon will simply not inflate
because there is no physical space for the balloon to expand and
because the inflation pressure remains beneath the urethral
damaging pressure threshold. If the inflation device is configured
for low pressure, even maximum delivered pressure to the balloon
will be insufficient to inflate the balloon within the urethra,
thereby preventing any possibility of balloon inflation inside the
urethra.
[0156] In the other case where the balloon is inflated properly
within the bladder but the catheter is improperly removed out from
the patient without deflating the balloon, safety devices of the
invention prevent tearing of the urethra upon exit. Any combination
of the internal balloon valve 1012 (e.g., the slit valve of FIG. 13
formed through the wall of a portion of the drainage lumen 1120
located inside the balloon 1010, 1610) and the removable proximal
balloon seal 1620 can be used; one or both can be employed to
provide the safety features of the invention. In operation, when a
predetermined inflation pressure is reached, the internal balloon
valve 1012 opens and any fluid in the balloon 1010, 1610 is emptied
through the drainage lumen 1120 into the bladder (distal) and/or
the external drain bag (proximal), the latter of which is not
illustrated. As set forth above, the point at which pressure causes
the internal balloon valve 1012 to open is defined to be less than
the pressure needed to damage the urethra when a fully inflated
prior-art balloon catheter is improperly removed as described
herein. In a low-pressure state, in which the balloon 1010, 1610 is
filled with a fluid (either liquid or gas), there is not enough
pressure to force open the internal balloon valve 1012 and permit
exit of the fluid out from the balloon 1010, 1610. In a
higher-pressure state (below urethra damage pressure), in contrast,
pressure exerted on the fluid is sufficient to open the internal
balloon valve 1012, thus permitting the fluid to quickly drain out
of the balloon 1010, 1610 and into the drainage lumen 1120.
[0157] In a situation where the balloon 1010, 1610 is in the
urethra and inflation is attempted, pressure exerted by the
surrounding urethral wall on the inflating balloon 1010, 1610 will
cause the internal balloon valve 1012 to open up well before the
balloon 1010, 1610 could inflate. Thus, the balloon inflation fluid
will, instead of filling the balloon 1010, 1610, exit directly into
the drainage lumen 1120. In an alternative embodiment, the fluid
used for inflation can be colored to contrast with urine (or any
other fluid that is envisioned to pass through the drainage lumen).
Thus, if the balloon 1010, 1610 is inserted only into the urethra
and inflation is attempted, the inflating fluid will immediately
exit into the drainage lumen and enter the exterior
(non-illustrated) drain bag. Thus, within a few seconds, the
technician will know if the balloon 1010, 1610 did not enter the
bladder and inflate therein properly by seeing the colored
inflation fluid in the drain bag. In such a situation, the
technician needs to only insert the catheter further into the
urethra and attempt inflation again. The absence of further colored
inflation fluid in the drain bag indicates that correct balloon
inflation occurred.
[0158] To enhance placement of this catheter in the bladder in the
ideal position, in an alternative exemplary embodiment, a visual
aid 1030, 1032 for insertion is provided by marking the catheter
shaft 1020. This visual aid can be on the exterior surface or it
can be embedded within the material comprising the shaft as long as
it is visible to medical personnel. For, example, it could be an
embedded band of colored plastic or radiopaque material, or it
could just be an inked circumferential line. Because male and
female patients have urethras of different lengths, a first marker
1030 can be used to indicate an average urethra length 1031 for a
male and a second marker 1032 can be used to indicate an average
urethra length 1033 for a female.
[0159] In this way, if, after believing that insertion is
"correct," the user still sees the marking outside the patient, the
user can double check the insertion before inflating the balloon
(which would occur in the urethra if not installed far enough
therein) and entirely prevent injury-causing inflation within the
urethra. Additionally, these markings 1030, 1032 can provide
immediate indications to medical personnel when it is not known
that a patient has jerked out the catheter partially or the
catheter snagged on the environment and pulled out partially. In
either situation, if the medical personnel looks at the catheter
and sees the respective marking 1030, 1032, then it becomes
immediately clear that the inflated balloon catheter has been
improperly removed, but partially, and immediate corrective action
can be taken.
[0160] It is noted that this marking feature is only being shown on
the catheter of FIG. 9 for illustrative purposes. It is not
intended to be limited to the catheter of FIG. 9 and is to be
understood as applying to any and/or all of the exemplary
embodiments described herein.
[0161] In the situation where the balloon 1010, 1610 is inflated
within the bladder and the catheter 100 is pulled out from the
bladder without deflating the balloon 1010, 1610, pressure exerted
by the bladder-urethral junction 11 upon the inflated balloon 1010,
1610 will cause the valve 1012 to open up quickly and cause fluid
flow into the drainage lumen 1120 before injury occurs to the
junction 11 or the urethra. If, in such a situation, the catheter
is also equipped with the removable balloon end (e.g., proximal end
1620), then, as the removable balloon end is peeling off, the slit
valve opens up to relieve pressure either before or at the same
time the peeling off occurs. This allows the inflation fluid to
exit even faster than if just the valve 1012 is present.
[0162] FIGS. 16 to 18 illustrate an exemplary embodiment of the
inventive catheter 1600 with the everting removable balloon 1610.
These figures illustrate the situation where the balloon 1610 is
inflated within the bladder and, as indicated by the pull arrow,
the catheter 1600 is pulled out from the bladder without deflating
the balloon 1610. Here, the distal seal 1640 of the balloon 1610 is
fixed to the distal tip portion 1650 of the catheter 1600, which
tip 5 has a reduced outer diameter as compared to the drainage
catheter shaft 1630, and the proximal seal 1620 is removably
attached (e.g., with a compression seal) to the drainage catheter
shaft 1630. The pulling force causes the drainage catheter shaft
1630 to move in the proximal direction out of the urethra and,
thereby, compress the proximal side of the inflated balloon 1610
against the bladder-urethral junction 11. As the catheter shaft
1630 moves proximally, the force on the proximal seal 1620
increases until the seal 1620 breaks free of the catheter shaft
1630, referred to herein as the breakaway point. FIG. 17
illustrates the now partially inflated balloon 1610 just after the
breakaway point. Because the diameter of the distal tip portion
1650 is reduced in comparison to the distal end of the catheter
shaft 1630, a gap opens up between the inner diameter of the
proximal seal portion of the balloon 1610 and the outer diameter of
the distal tip portion 1650. This gap allows the inflating fluid to
exit the balloon 1610 quickly into one or both of the urethra and
the bladder before injury occurs to the junction 11 or to the
urethra. As the central portion of the balloon 1610 is still larger
than the urethral opening of the junction 11, the friction and
force imparted on the balloon 1610 causes the balloon 1610 to roll
over itself, i.e., evert, until it is entirely everted as shown in
FIG. 18. At this time, all of the inflating fluid is either in the
urethra and/or in the bladder.
[0163] In an exemplary embodiment of the removable proximal balloon
seal 1620, a pulling force in a range of 1 to 15 pounds will cause
the proximal balloon seal 1620 to pull free and allow eversion of
the balloon 1610, i.e., the breakaway point. In another exemplary
embodiment, the range of force required to meet the breakaway point
is between 1 and 5 pounds, in particular, between 1.5 and 2
pounds.
[0164] With regard to additional exemplary embodiments of
self-deflating or automatically deflating balloon catheters
according to the invention, FIGS. 19 and 20 are provided to
illustrate the construction and processes for manufacturing prior
art urinary catheters, also referred to as Foley catheters.
Although prior art urinary catheters are used herein to assist in
the understanding of the exemplary embodiments of urinary balloon
catheters according to the invention, neither are used herein to
imply that the invention is solely applicable to urinary-type
catheters. Instead, the technology described herein can be applied
to any balloon catheter, including all mentioned herein.
[0165] FIG. 19 shows the balloon portion of the prior art catheter
1900 with the balloon in its uninflated state. An annular inner
lumen wall 1910 (red) defines therein a drainage lumen 1912. At one
circumferential longitudinal extent about the inner lumen wall
1910, an inflation lumen wall 1920 (orange) defines an inflation
lumen 1922 and a balloon inflation port 1924 fluidically connected
to the inflation lumen 1922; in standard urinary catheters, there
is only one inflation lumen 1922 and one inflation port 1924. The
views of FIGS. 19 and 20 show a cross-section through the inflation
lumen 1922 and inflation port 1924. If the inflation lumen 1922
extended all of the way through the catheter 1900 to its distal end
(to the left of FIGS. 19 and 20), then the balloon could not
inflate as all inflation liquid would exit the distal end.
Therefore, in order to allow inflation of the balloon, a lumen plug
1926 (black) closes the inflation lumen 1922 distal of the
inflation port 1924. In this exemplary illustration, the lumen plug
1926 starts at a position distal of the inflation port 1924 at the
inflation lumen 1922.
[0166] About the inner lumen and inflation lumen walls 1910, 1920
around the inflation port 1924 is a tube of material that forms the
balloon interior wall 1930 (green). The tube forming the balloon
interior wall 1930 is fluid-tightly sealed against the respective
inner walls 1910, 1920 only at the proximal and distal ends of the
tube. Accordingly, a pocket is formed therebetween. An outer wall
1940 (yellow) covers all of the walls 1910, 1920, 1926, 1930 and
does so in what has referred to herein as a fluid-tight manner,
meaning that any fluid used to blow up the balloon through the
inflation lumen 1922 and the inflation port 1924 will not exit the
catheter 1900 through the fluid-tight connection. FIG. 20
illustrates the fluid inflating the balloon (indicated with dashed
arrows). Because at least the balloon interior wall 1930 and the
outer wall 1940 are elastomeric, pressure exerted by the inflating
fluid 2000 against these walls will cause them to balloon outwards
as, for example, shown in FIG. 20. When the non-illustrated
proximal end of the catheter 1900 is sealed with the fluid 2000
therein (e.g., with at least a part of a luer connector as shown in
FIG. 3), the catheter 1900 will remain in the shape shown in FIG.
20.
[0167] As set forth above, the balloon 2010 of a urinary catheter
should be inflated only when in the bladder 2020. FIG. 20 shows the
catheter 1900 correctly inflated in the bladder 2020 and then, if
needed, pulled proximally so that the inflated balloon 2010 rests
against and substantially seals off the urethra 2030 from the
interior of the bladder 2020. "Substantially," as used in this
regard means that most or all of the urine in the bladder 2020 will
drain through the drain lumen 1912 and will not pass around the
inflated balloon 2010 more than is typical and/or required for
correctly implanted urinary catheters. It is known that an
insubstantial amount of urine will pass the balloon 2010 and,
advantageously, lubricate the urethra 2030 but will not leak out
the end of the urethra as muscles in the various anatomy of males
and females will seal the end with sufficient force to prevent
significant leakage.
[0168] Even though each of the walls is shown in different colors
herein, the different colors do not imply that the respective walls
must be made of different materials. These colors are used merely
for clarity purposes to show the individual parts of the prior art
and inventive catheters described herein. As will be described in
further detail below, most of the different colored walls actually
are, in standard urinary catheters, made of the same material. Some
of the biocompatible materials used for standard Foley catheters
include latex (natural or synthetic), silicone rubber, and
thermoplastic elastomers (TPEs) including styrenic block
copolymers, polyolefin blends, elastomeric alloys (TPE-v or TPV),
thermoplastic polyurethanes, thermoplastic copolyester, and
thermoplastic polyamides.
[0169] One exemplary process for creating the prior art urinary
catheters starts with a dual lumen extrusion of latex. The dual
lumen, therefore, already includes both the drainage lumen 1912 and
the inflation lumen 1922. Both lumen 1912, 1922, however, are
extruded without obstruction and without radial ports. Therefore,
in order to have the inflation port 1924, a radial hole is created
from the outside surface inwards to the inflation lumen. Sealing
off of the distal end of the inflation lumen 1922 is performed in a
subsequent step. The tube making up the inner balloon wall 1930 is
slid over the distal end of the multi-lumen extrusion 1910, 1920 to
cover the inflation port and is fluid-tightly sealed to the inner
multi-lumen extrusion at both ends of the tube but not in the
intermediate portion. This tube can be made of latex as well and,
therefore, can be secured to the latex multi-lumen extrusion in any
known way to bond latex in a fluid-tight manner. At this point, the
entire sub-assembly is dipped into latex in its liquid form to
create the outer wall 1940. The latex is allowed to enter at least
a portion of the distal end of the inflation lumen 1922 but not so
far as to block the inflation port 1924. When the latex cures, the
balloon 2010 is fluid tight and can only be fluidically connected
to the environment through the non-illustrated, proximal-most
opening of the inflation port, which is fluidically connected to
the inflation lumen 1922. In this process, the inner wall 1910, the
inflation lumen wall 1920, the plug 1926, the balloon inner wall
1930, and the outer wall 1940 are all made of the same latex
material and, therefore, together form a very secure water-tight
balloon 2010.
[0170] As set forth above, all prior art balloon catheters are
designed to deflate only when actively deflated, either by a
syringe similar to the one that inflated it or by surgery after the
physician diagnoses the balloon as not being able to deflate, in
which circumstance, a procedure to pop the balloon surgically is
required.
[0171] Described above are various embodiments of self-deflating or
automatically deflating catheters according to the invention. FIGS.
21 to 33 illustrate automatically deflating, stretch-valve balloon
catheters in still other exemplary embodiments of the present
invention. FIGS. 21 to 23 show a first exemplary embodiment of a
stretch-valve balloon catheter 2100 according to the invention,
FIG. 21 illustrating the balloon portion of the inventive catheter
2100 with the balloon in its uninflated state. An annular inner
lumen wall 2110 (red) defines therein a drainage lumen 2112. At one
or more circumferential longitudinal extents about the inner lumen
wall 2110, an inflation lumen wall 2120 (orange) defines an
inflation lumen 2122 and a balloon inflation port 2124 fluidically
connected to the inflation lumen 2122; in the inventive catheter,
there can be more than one inflation lumen 2122 and corresponding
inflation port 2124 even though only one is shown herein.
Accordingly, the views of FIGS. 21 to 23 show a cross-section
through the single inflation lumen 2122 and single inflation port
2124. A lumen plug 2126 (black) closes the inflation lumen 2122
distal of the inflation port 2124. In this exemplary illustration,
the lumen plug 2126 starts at a position distal of the inflation
port 2124 at the inflation lumen 2122. This configuration is only
exemplary and can start at the inflation port 2124 or anywhere
distal thereof.
[0172] About the inner lumen and inflation lumen walls 2110, 2120
around the inflation port 2124 is a tube of material that forms the
balloon interior wall 2130 (green). The tube of the balloon
interior wall 2130 is fluid-tightly sealed against the respective
inner walls 2110, 2120 only at the proximal and distal ends of the
tube. Accordingly, a pocket is formed therebetween. An outer wall
2140 (yellow) covers all of the walls 2110, 2120, 2126, 2130 in a
fluid-tight manner. FIG. 21 illustrates the fluid about to inflate
the balloon (indicated with dashed arrows). Because at least the
balloon interior wall 2130 and the outer wall 2140 are elastomeric,
pressure exerted by the inflating fluid 2200 against these walls
will cause them to balloon outwards as, for example, shown in FIG.
22. When the non-illustrated proximal end of the catheter 2100 is
sealed with the fluid 2200 therein (e.g., with at least a part of a
luer connector as shown in FIG. 3), the catheter 2100 will remain
in the shape shown in FIG. 22.
[0173] FIG. 22 shows the catheter 2100 correctly inflated in the
bladder 2020 and then, if needed, pulled proximally so that the
inflated balloon 2210 rests against and substantially seals off the
urethra 2030 from the interior of the bladder 2020.
[0174] The stretch-valve of the exemplary embodiment of FIGS. 21 to
23 has three different aspects. The first is a hollow,
stretch-valve tube 2220 that is disposed in the inflation lumen
2122 to not hinder inflation of the balloon 2210 with the fluid
2200. While the diameter of the stretch-valve tube 2220 can be any
size that accommodates substantially unhindered fluid flow through
the inflation lumen 2122, one exemplary inner diameter of the
stretch-valve tube 2220 is substantially equal to the diameter of
the inflation lumen 2122 and the outer diameter of the
stretch-valve tube 2220 is just slightly larger than the diameter
of the inflation lumen 2122 (e.g., the wall thickness of the tube
can be between 0.05 mm and 0.2 mm). The proximal end of the
stretch-valve tube 2220 in this exemplary embodiment is proximal of
a proximal end of the balloon inner wall 2130. The distal end of
the stretch-valve tube 2220 is somewhere near the proximal end of
the balloon inner wall 2130; the distal end can be proximal, at, or
distal to the proximal end of the balloon inner wall 2130 and
selection of this position is dependent upon the amount of stretch
S required to actuate the stretch-valve of the inventive catheter
2100 as described below. Another exemplary embodiment of the
stretch-valve tube 2220 has one or more of the proximal and distal
ends thereof larger in outer diameter than an intermediate portion
of the stretch-valve tube 2220. Thus, if one end is larger, the
stretch-valve tube 2220 has a "club" shape and, if both ends are
larger, the stretch-valve tube 2220 has a "dumbbell" shape. An
exemplary configuration of a dumbbell shaped stretch-valve tube is
described hereinbelow.
[0175] In FIG. 22, the distal end of the stretch-valve tube 2220 is
shown at the proximal end of the balloon inner wall 2130. Two ports
are formed proximal of the balloon 2210. A proximal port (purple)
2150 is formed through the outer wall 2140 and through the
inflation lumen wall 2020 overlapping at least a portion of the
proximal end of the stretch-valve tube 2220. In this manner, a
portion of the outer surface of the proximal end of the
stretch-valve tube 2220 at the proximal port 2150 is exposed to the
environment but there is no fluid communication with the inflation
lumen 2122 and the proximal port 2150. A distal port (white) 2160
is formed through the outer wall 2140 and through the inflation
lumen wall 2020 overlapping at least a portion of the distal end of
the stretch-valve tube 2220. In this manner, a portion of the outer
surface of the distal end of the stretch-valve tube 2220 at the
distal port 2160 is exposed to the environment but there is no
fluid communication from the inflation lumen 2122 to the distal
port 2160. To secure the stretch-valve tube 2220 in the catheter
2100, the proximal port 2150 is filled with a material that fixes
the proximal end of the stretch-valve tube 2220 to at least one of
the outer wall 2140 and the inflation lumen wall 2020. In one
exemplary embodiment, an adhesive bonds the proximal end of the
stretch-valve tube 2220 to both the outer wall 2140 and the
inflation lumen wall 2120.
[0176] In such a configuration, therefore, any proximal movement of
the catheter 2100 at or proximal of the proximal port 2150 will
also move the stretch-valve tube 2220 proximally; in other words,
the distal end of the stretch-valve tube 2220 can slide S within
the inflation lumen 2122 in a proximal direction. FIG. 23
illustrates how the slide-valve of the invention operates when the
proximal end of the catheter 2100 is pulled with a force that is no
greater than just before injury would occur to the bladder-urethral
junction or the urethra if the catheter 2100 was still inflated
when the force was imparted. In an exemplary embodiment of the
stretch valve of FIGS. 21 to 23, a pulling force in a range of 1 to
15 pounds will cause the stretch-valve tube 2220 to slide
proximally S to place the distal end of the stretch-valve tube 2220
just proximal of the distal port 2160, i.e., the deflation point of
the stretch-valve shown in FIG. 23. In another exemplary
embodiment, the range of force required to meet the deflation point
is between 1 and 5 pounds, in particular, between 1.5 and 2
pounds.
[0177] As can be seen in FIG. 23, when the deflation point of the
stretch-valve is reached, the interior of the balloon 2210 becomes
fluidically connected to the distal port 2160. Because the distal
port 2160 is open to the environment (e.g., the interior of the
bladder 2020) and due to the fact that the bladder is relatively
unpressurized as compared to the balloon 2210, all internal
pressure is released from the balloon 2210 to eject the inflating
fluid 2200 into the bladder 2020 (depicted by dashed arrows),
thereby causing the balloon 2210 to deflate rapidly (depicted by
solid opposing arrows). It is noted that the distance X (see FIG.
22) between the inflation port 2124 and the distal port 2160
directly impacts the rate at which the balloon 2120 deflates. As
such, reducing this distance X will increase the speed at which the
balloon 2210 deflates. Also, the cross-sectional areas of the
inflation port 2124, the inflation lumen 2122, and the distal port
2160 directly impact the rate at which the balloon 2220 deflates.
Further, any changes in direction of the fluid can hinder the rate
at which the balloon deflates. One way to speed up deflation can be
to shape the distal port 2160 in the form of a non-illustrated
funnel outwardly expanding from the inflation lumen 2122. Another
way to speed up deflation is to have two or more inflation lumens
2122 about the circumference of the inner lumen wall 2110 and to
have corresponding sets of a stretch-valve tube 2220, a proximal
port 2150, and a distal port 2160 for each inflation lumen
2122.
[0178] Still another possibility for rapidly deflating an inflated
balloon is to drain the fluid 2200 into the drain lumen 2112
instead of the bladder. This exemplary embodiment is illustrated in
FIGS. 24 to 26. FIG. 24 illustrates the balloon portion of the
inventive catheter 2400 with the balloon in its uninflated state.
An annular inner lumen wall 2410 (red) defines therein a drainage
lumen 2412. At one or more circumferential longitudinal extents
about the inner lumen wall 2410, an inflation lumen wall 2420
(orange) defines an inflation lumen 2422 and a balloon inflation
port 2424 fluidically connected to the inflation lumen 2422; in the
inventive catheter, there can be more than one inflation lumen 2422
and corresponding inflation port 2424 even though only one is shown
herein. Accordingly, the views of FIGS. 24 to 26 show a
cross-section through the single inflation lumen 2422 and single
inflation port 2424. A lumen plug 2426 (black) closes the inflation
lumen 2422 distal of the inflation port 2424. In this exemplary
illustration, the lumen plug 2426 starts at a position distal of
the inflation port 2424 at the inflation lumen 2422. This
configuration is only exemplary and can start at the inflation port
2424 or anywhere distal thereof.
[0179] About the inner lumen and inflation lumen walls 2410, 2420
around the inflation port 2424 is a tube of material that forms the
balloon interior wall 2430 (green). The tube of the balloon
interior wall 2430 is fluid-tightly sealed against the respective
inner walls 2410, 2420 only at the proximal and distal ends of the
tube. Accordingly, a pocket is formed therebetween. An outer wall
2440 (yellow) covers all of the walls 2410, 2420, 2426, 2430 in a
fluid-tight manner. FIG. 24 illustrates the fluid about to inflate
the balloon (indicated with dashed arrows). Because at least the
balloon interior wall 2430 and the outer wall 2440 are elastomeric,
pressure exerted by the inflating fluid 2200 against these walls
will cause them to balloon outwards as, for example, shown in FIG.
25. When the non-illustrated proximal end of the catheter 2400 is
sealed with the fluid 2200 therein (e.g., with at least a part of a
luer connector as shown in FIG. 3), the catheter 2400 will remain
in the shape shown in FIG. 25.
[0180] FIG. 25 shows the catheter 2400 correctly inflated in the
bladder 2020 and then, if needed, pulled proximally so that the
inflated balloon 2510 rests against and substantially seals off the
urethra 2030 from the interior of the bladder 2020.
[0181] The stretch-valve of the exemplary embodiment of FIGS. 24 to
26 has three different aspects. The first is a hollow,
stretch-valve tube 2520 that is disposed in the inflation lumen
2422 to not hinder inflation of the balloon 2510 with the fluid
2200. While the diameter of the stretch-valve tube 2520 can be any
size that accommodates substantially unhindered fluid flow through
the inflation lumen 2422, one exemplary inner diameter of the
stretch-valve tube 2520 is substantially equal to the diameter of
the inflation lumen 2422 and the outer diameter of the
stretch-valve tube 2520 is just slightly larger than the diameter
of the inflation lumen 2122 (e.g., the wall thickness of the tube
can be between 0.05 mm and 0.2 mm). The proximal end of the
stretch-valve tube 2520 in this exemplary embodiment is disposed
proximal of a proximal end of the balloon inner wall 2430. The
distal end of the stretch-valve tube 2520 is somewhere near the
proximal end of the balloon inner wall 2430; the distal end can be
proximal, at, or distal to the proximal end of the balloon inner
wall 2430 and selection of this position is dependent upon the
amount of stretch S required to actuate the stretch-valve of the
inventive catheter 2400 as described below. Another exemplary
embodiment of the stretch-valve tube 2520 has one or more of the
proximal and distal ends thereof larger in outer diameter than an
intermediate portion of the stretch-valve tube 2520. Thus, if one
end is larger, the stretch-valve tube 2520 has a "club" shape and,
if both ends are larger, the stretch-valve tube 2520 has a
"dumbbell" shape. An exemplary configuration of a dumbbell shaped
stretch-valve tube is described hereinbelow.
[0182] In the exemplary embodiment of FIG. 25, the distal end of
the stretch-valve tube 2520 is shown at proximal end of the balloon
inner wall 2430. Two ports are formed, one proximal of the balloon
2510 and one proximal of the inflation port 2424. A proximal port
(purple) 2450 is formed through the outer wall 2440 and through the
inflation lumen wall 2420 to overlap at least a portion of the
proximal end of the stretch-valve tube 2520. In this manner, a
portion of the outer surface of the proximal end of the
stretch-valve tube 2520 at the proximal port 2450 is exposed to the
environment but there is no fluid communication between the
inflation lumen 2422 and the proximal port 2450. A distal port
(white) 2460 is formed through the inner lumen wall 2410 anywhere
proximal of the inflation port 2424 to overlap a least a portion of
the distal end of the stretch-valve tube 2520. In this manner, a
portion of the outer surface of the distal end of the stretch-valve
tube 2520 at the distal port 2460 is exposed to the drainage lumen
2412 but there is no fluid communication between the inflation
lumen 2422 and the distal port 2460. To secure the stretch-valve
tube 2520 in the catheter 2400, the proximal port 2450 is filled
with a material that fixes the proximal end of the stretch-valve
tube 2520 to at least one of the outer wall 2440 and the inflation
lumen wall 2420. In one exemplary embodiment, an adhesive bonds the
proximal end of the stretch-valve tube 2520 to both the outer wall
2440 and the inflation lumen wall 2420.
[0183] In such a configuration, therefore, any proximal movement of
the catheter 2400 at or proximal to the proximal port 2450 will
also move the stretch-valve tube 2520 proximally; in other words,
the distal end of the stretch-valve tube 2520 can slide S within
the inflation lumen 2422 in a proximal direction. FIG. 26
illustrates how the slide-valve of the invention operates when the
proximal end of the catheter 2400 is pulled to a force that is no
greater than just before injury would occur to the bladder-urethral
junction or the urethra if the catheter 2400 was still inflated
when the force was imparted. In an exemplary embodiment of the
stretch valve of FIGS. 24 to 26, a pulling force in a range of 1 to
15 pounds will cause the stretch-valve tube 2520 to slide
proximally S to place the distal end of the stretch-valve tube 2520
just proximal of the distal port 2460, i.e., the deflation point of
the stretch-valve shown in FIG. 26. In another exemplary
embodiment, the range of force required to meet the deflation point
is between 1 and 5 pounds, in particular, between 1.5 and 2
pounds.
[0184] As can be seen in FIG. 26, when the deflation point of the
stretch-valve is reached, the interior of the balloon 2510 becomes
fluidically connected to the distal port 2460. Because the distal
port 2460 is open to the drainage lumen 2412 (which is open the
interior of the bladder 2020 and the non-illustrated, proximal
drainage bag) and due to the fact that the bladder is relatively
unpressurized as compared to the balloon 2510, all internal
pressure is released from the balloon 2510 to eject the inflating
fluid 2200 into the drainage lumen 2412 (depicted by dashed arrows
in FIG. 26), thereby causing the balloon 2510 to deflate rapidly
(depicted by solid opposing arrows in FIG. 26). Again, it is noted
that the distance X between the inflation port 2424 and the distal
port 2460 (see FIG. 25) directly impacts the rate at which the
balloon 2510 deflates. As such, having this distance X be smaller
will increase the speed at which the balloon 2510 deflates. Also,
the cross-sectional areas of the inflation port 2424, the inflation
lumen 2422, and the distal port 2460 directly impact the rate at
which the balloon 2120 deflates. Further, any changes in direction
of the fluid can hinder the rate at which the balloon deflates. One
way to speed up deflation can be to shape the distal port 2460 in
the form of a funnel outwardly expanding from the inflation lumen
2422. Another way to speed up deflation can be to have two or more
inflation lumens 2422 about the circumference of the inner lumen
wall 2410 and to have corresponding sets of a stretch-valve tube
2520, a proximal port 2450, and a distal port 2460 for each
inflation lumen 2422.
[0185] Yet another exemplary embodiment that is not illustrated
herein is to combine both of the embodiments of FIGS. 21 to 23 and
24 to 26 to have the fluid 2200 drain out from both of the distal
ports 2160, 2460 into both the bladder 2020 and the drain lumen
2112, respectively.
[0186] Still another possibility for rapidly deflating an inflated
balloon is to drain the fluid 2200 directly into the drain lumen
2712 in a straight line without any longitudinal travel X. This
exemplary embodiment is illustrated in FIGS. 27 to 29. FIG. 27
illustrates the balloon portion of the inventive catheter 2700 with
the balloon in its uninflated state. An annular inner lumen wall
2710 (red) defines therein a drainage lumen 2712. At one or more
circumferential longitudinal extents about the inner lumen wall
2710, an inflation lumen wall 2720 (orange) defines an inflation
lumen 2722 and a balloon inflation port 2724 fluidically connected
to the inflation lumen 2722; in the inventive catheter, there can
be more than one inflation lumen 2722 and corresponding inflation
port 2724 even though only one is shown herein. Accordingly, the
views of FIGS. 27 to 29 show a cross-section through the single
inflation lumen 2722 and single inflation port 2724. A lumen plug
2726 (black) closes the inflation lumen 2722 distal of the
inflation port 2724. In this exemplary illustration, the lumen plug
2726 starts at a position distal of the inflation port 2724 at the
inflation lumen 2722. This configuration is only exemplary and can
start at the inflation port 2724 or anywhere distal thereof.
[0187] About the inner lumen and inflation lumen walls 2710, 2720
around the inflation port 2724 is a tube of material that forms the
balloon interior wall 2730 (green). The tube of the balloon
interior wall 2730 is fluid-tightly sealed against the respective
inner walls 2710, 2720 only at the proximal and distal ends of the
tube. Accordingly, a pocket is formed therebetween. An outer wall
2740 (yellow) covers all of the walls 2710, 2720, 2726, 2730 in a
fluid-tight manner. FIG. 27 illustrates the fluid about to inflate
the balloon (indicated with dashed arrows). Because at least the
balloon interior wall 2730 and the outer wall 2740 are elastomeric,
pressure exerted by the inflating fluid 2200 against these walls
will cause them to balloon outwards as, for example, shown in FIG.
28. When the non-illustrated proximal end of the catheter 2700 is
sealed with the fluid 2200 therein (e.g., with at least a part of a
luer connector as shown in FIG. 3), the catheter 2700 will remain
in the shape shown in FIG. 28.
[0188] FIG. 28 shows the catheter 2700 correctly inflated in the
bladder 2020 and then, if needed, pulled proximally so that the
inflated balloon 2810 rests against and substantially seals off the
urethra 2030 from the interior of the bladder 2020.
[0189] The stretch-valve of the exemplary embodiment of FIGS. 27 to
29 has three different aspects. The first is a hollow,
stretch-valve tube 2820 that is disposed in the inflation lumen
2722 to not hinder inflation of the balloon 2810 with the fluid
2200. While the diameter of the stretch-valve tube 2820 can be any
size that accommodates substantially unhindered fluid flow through
the inflation lumen 2722, one exemplary inner diameter of the
stretch-valve tube 2820 is substantially equal to the diameter of
the inflation lumen 2722 and the outer diameter of the
stretch-valve tube 2820 is just slightly larger than the diameter
of the inflation lumen 2722 (e.g., the wall thickness of the tube
can be between 0.05 mm and 0.2 mm). The proximal end of the
stretch-valve tube 2820 in this exemplary embodiment is proximal of
a proximal end of the balloon inner wall 2730. The distal end of
the stretch-valve tube 2820 is somewhere near the proximal end of
the balloon inner wall 2730; the distal end can be proximal, at, or
distal to the proximal end of the balloon inner wall 2730 and
selection of this position is dependent upon the amount of stretch
S required to actuate the stretch-valve of the inventive catheter
2700 as described below. Another exemplary embodiment of the
stretch-valve tube 2820 has one or more of the proximal and distal
ends thereof larger in outer diameter than an intermediate portion
of the stretch-valve tube 2820. Thus, if one end is larger, the
stretch-valve tube 2820 has a "club" shape and, if both ends are
larger, the stretch-valve tube 2820 has a "dumbbell" shape. An
exemplary configuration of a dumbbell shaped stretch-valve tube is
described hereinbelow.
[0190] In the exemplary embodiment of FIG. 28, the distal end of
the stretch-valve tube 2820 is shown between the inflation port
2724 and the proximal end of the balloon inner wall 2730. Two ports
are formed, one proximal of the balloon 2810 and one between the
inflation port 2724 and the proximal end of the balloon inner wall
2730. A proximal port 2750 is formed through the outer wall 2740
through the inflation lumen wall 2720 to overlap at least a portion
of the proximal end of the stretch-valve tube 2820. In this manner,
a portion of the outer surface of the proximal end of the
stretch-valve tube 2820 at the proximal port 2750 is exposed to the
environment but there is no fluid communication between the
inflation lumen 2722 and the proximal port 2750. A distal port
(white) 2760 is formed through both inflation lumen wall 2720 and
the inner wall 2710 distal of the proximal connection of the
balloon inner wall 2730 to overlap a least a portion of the distal
end of the stretch-valve tube 2820. In this manner, opposing
portions of the outer surface of the distal end of the
stretch-valve tube 2820 at the distal port 2760 are exposed, one
exposed to the interior of the balloon 2810 and one exposed to the
drainage lumen 2712 but there is no fluid communication between
either the inflation lumen 2722 or the drainage lumen 2712 and the
distal port 2760. To secure the stretch-valve tube 2820 in the
catheter 2700, the proximal port 2750 is filled with a material
that fixes the proximal end of the stretch-valve tube 2820 to at
least one of the outer wall 2740 and the inflation lumen wall 2720.
In one exemplary embodiment, an adhesive bonds the proximal end of
the stretch-valve tube 2820 to both the outer wall 2740 and the
inflation lumen wall 2720. In the exemplary embodiment, the
adhesive can be the same material as any or all of the walls 2710,
2720, 2730, 2740 or it can be a different material. If the outer
wall 2740 is formed by a dipping of the interior parts into a
liquid bath of the same material as, for example, a dual lumen
extrusion including the inner wall 2710 and the inflation lumen
wall 2720, then, when set, the outer wall 2740 will be integral to
both the inner wall 2710 and the inflation lumen wall 2720 and will
be fixedly connected to the stretch-valve tube 2820 through the
proximal port 2750.
[0191] In such a configuration, therefore, any proximal movement of
the catheter 2700 at or proximal to the proximal port 2750 will
also move the stretch-valve tube 2820 proximally; in other words,
the distal end of the stretch-valve tube 2820 can slide S within
the inflation lumen 2722 in a proximal direction. FIG. 29
illustrates how the slide-valve of the invention operates when the
proximal end of the catheter 2700 is pulled to a force that is no
greater than just before injury would occur to the bladder-urethral
junction or the urethra if the catheter 2700 was still inflated
when the force was imparted. In an exemplary embodiment of the
stretch valve of FIGS. 27 to 29, a pulling force in a range of 1 to
15 pounds will cause the stretch-valve tube 2820 to slide
proximally S to place the distal end of the stretch-valve tube 2820
just proximal of the distal port 2760, i.e., the deflation point of
the stretch-valve shown in FIG. 29. In another exemplary
embodiment, the range of force required to meet the deflation point
is between 1 and 5 pounds, in particular, between 1.5 and 2
pounds.
[0192] As can be seen in FIG. 29, when the deflation point of the
stretch-valve is reached, the interior of the balloon 2810 becomes
fluidically connected to both the upper and lower portions of the
distal port 2760 in a direct and straight line. Because the distal
port 2760 is open to the drainage lumen 2712 (which is open the
interior of the bladder 2020 and to the non-illustrated, proximal
drain bag) and due to the fact that the bladder is relatively
unpressurized as compared to the balloon 2810, an internal pressure
is released from the balloon 2810 to eject the inflating fluid 2200
into the drainage lumen 2712 (depicted by dashed arrows in FIG.
29), thereby causing the balloon 2810 to deflate rapidly (depicted
by solid opposing arrows). Unlike the embodiments above, the
distance X between the deflation port (the upper part of distal
port 2760) and the lower part of distal port 2760 is
zero--therefore, the rate at which the balloon 2510 deflates cannot
be made any faster (other than expanding the area of the distal
port 2760). It is further noted that the inflation port 2724 also
becomes fluidically connected to the drain lumen 2712 and,
therefore, drainage of the fluid 2200 occurs through the inflation
port 2724 as well (also depicted by a dashed arrow). The
cross-sectional area of the inflation lumen 2722 only slightly
impacts the rate of balloon deflation, if at all. One way to speed
up deflation can be to shape the distal port 2760 in the form of a
funnel outwardly expanding in a direction from the outer
circumference of the catheter 2700 inwards towards the drainage
lumen 2712. Another way to speed up deflation can be to have two or
more inflation lumens 2722 about the circumference of the inner
lumen wall 2710 and to have corresponding sets of a stretch-valve
tube 2820, a proximal port 2750, and a distal port 2760 for each
inflation lumen 2722.
[0193] FIG. 30 reproduces FIG. 27 to assist in explaining FIGS. 31
and 32 on the same page. FIGS. 31 and 32 show, respectively, the
closed and opened positions of the stretch-valve tube 2820 in FIGS.
28 and 29. These figures are viewed in an orientation turned ninety
degrees counterclockwise with regard to a central, longitudinal
axis of the catheter 2700 viewed along the axis towards the distal
end from the proximal end so that the view looks down upon the
distal port 2760. As can be seen, without pulling on the proximal
end of the catheter 2700 (FIG. 31), the stretch-valve tube 2820
blocks the distal port 2760. With a proximal force on the proximal
end of the catheter 2700, as shown in the orientation of FIG. 32,
the stretch-valve tube 2820 slides and no longer blocks the distal
port 2760.
[0194] FIGS. 33 to 36 show alternative exemplary embodiments for
the automatically deflating, stretch-valve, safety balloon catheter
according to the invention. Where various parts of the embodiments
are not described with regard to these figures (e.g., the balloon
interior wall), the above-mentioned parts are incorporated by
reference herein into these embodiments and are not repeated for
reasons of brevity.
[0195] FIG. 33 illustrates the balloon portion of the inventive
catheter 3300 with the balloon 3302 in a partially inflated state.
An annular inner lumen wall 3310 defines therein a drainage lumen
3312. At one or more circumferential longitudinal extents about the
inner lumen wall 3310, an inflation lumen wall 3320 defines an
inflation lumen 3322 and a balloon inflation port 3324 fluidically
connected to the inflation lumen 3322; in the inventive catheter,
there can be more than one inflation lumen 3322 and corresponding
inflation port 3324 even though only one is shown herein.
Accordingly, the views of FIGS. 33 to 36 show a cross-section
through the single inflation lumen and single inflation port. No
lumen plug closes the inflation lumen 3322 distal of the inflation
port 3324 (this is in contrast to the above-described exemplary
embodiments). In the exemplary embodiment of FIG. 33, a
stretch-valve mechanism 3330 serves to plug the inflation lumen
3322 distal of the inflation port 3324 as described in further
detail below. An outer wall 3340 covers all of the interior walls
3310 and 3320 in a fluid-tight manner and forms the exterior of the
balloon 3342 but does not cover the distal end of the inflation
lumen 3322. The outer wall 3340 is formed in any way described
herein and is not discussed in further detail here.
[0196] The stretch-valve mechanism 3330 is disposed in the
inflation lumen 3322 to not hinder inflation of the balloon 3302
with inflating fluid. A proximal, hollow anchor portion 3332 is
disposed in the inflation lumen 3320 proximal of the inflation port
3324. While the diameter of the hollow anchor portion 3332 can be
any size that accommodates substantially unhindered fluid flow
through the inflation lumen 3322, one exemplary inner diameter of
the hollow anchor portion 3332 is substantially equal to the
diameter of the inflation lumen 3322 and the outer diameter of the
hollow anchor portion 3332 is just slightly larger than the
diameter of the inflation lumen 3322 (e.g., the wall thickness of
the tube can be between 0.05 mm and 0.2 mm). The longitudinal
length of the hollow anchor portion 3332 is as long as desired to
be longitudinally fixedly secured within the inflation lumen 3322
when installed in place. The tube, from its shape alone, can
provide the securing connection but, also, an adhesive can be used
in any manner, one of which includes creating a proximal port as
shown in the above embodiments and utilizing the dipped exterior to
form the fixed connection. The distal end of the hollow anchor
portion 3332 in this exemplary embodiment is proximal of a proximal
end of the balloon 3302. The distal end of the hollow anchor
portion 3332 can be nearer to the inflation port 3324, but not at
or distal of the inflation port 3324; both ends of the hollow
anchor portion 3332 can be proximal, at, or distal to the proximal
end of the balloon 3302 and selection of this position is dependent
upon the amount of stretch that is desired to actuate the
stretch-valve of the inventive catheter 3300 as described below. In
the exemplary embodiment of FIG. 33, the stretch-valve mechanism
3330 also includes an intermediate stopper wire 3334 connected at
its proximal end to the hollow anchor portion 3332 and a stopper
3336 connected to the distal end of the stopper wire 3334. The
stopper 3336 is sized to be slidably disposed in the inflation
lumen 3322 while, at the same time, to provide a fluid-tight seal
so that liquid cannot pass from one side of the stopper 3336 to the
other side within the inflation lumen 3322. The stopper 3336 is
located distal of the inflation port 3324. The stopper wire 3334,
therefore, spans the inflation port 3324. Because the stopper 3336
must traverse the inflation port 3324, it must be just distal of
the inflation port 3324, but the hollow anchor portion can be
located anywhere proximal of the inflation port 3324. While the
length of the stopper wire 3334 needs to be sufficient to span the
inflation port 3324, it can be as long as desired, which will
depend on where the hollow anchor portion 3332 resides as well as
the amount of stretch desired. As the catheter 3300 stretches more
at its proximal end and less at its distal end when pulled from the
proximal end, the hollow anchor portion 3322 can be further
proximal in the inflation lumen 3322 than shown, and can even be
very close to or at the proximal end of the inflation lumen 3322.
Even though the term "wire" is used herein, this does not
necessarily mean that the wire structure is an incompressible rod.
It can, likewise, be a flexible but non-stretchable cable or cord.
In such a configuration, therefore, once the stopper 3336 is pulled
proximally (to the right in FIG. 33), it will not be forced back
distally once the stretching of the catheter is released. As such,
the flexible cable embodiment provides a single-actuation
valve.
[0197] In such a configuration, therefore, any proximal movement of
the catheter 3300 at or proximal to the inflation port 3324 will
also move the stretch-valve mechanism 3330 proximally; in other
words, the stopper 3336 slides proximally within the inflation
lumen 3322 from distal of the inflation port 3324 to a proximal
side of the inflation port 3324. When the proximal end of the
catheter 3300 is pulled to move the stopper 3336 across the
inflation port 3324 with a force that is no greater than just
before injury would occur to the bladder-urethral junction or the
urethra if the catheter 3300 was still inflated when the force was
imparted, fluid in the balloon 3342 can exit distally out the
inflation lumen 3322. In an exemplary embodiment of the stretch
valve of FIG. 33, a pulling force in a range of 1 to 15 pounds will
cause the stretch-valve mechanism 3330 to slide proximally to place
the stopper 3336 just proximal of the inflation port 3324, i.e.,
the deflation point of the stretch-valve shown in FIG. 33. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds. When the stopper 3336 traverses the
inflation port 3324, the balloon 3342 automatically deflates and
the inflating fluid exits into the bladder out the distal end of
the inflation lumen 3332, which is open at the distal end of the
catheter 3300.
[0198] FIG. 34 illustrates the balloon portion of the inventive
catheter 3400 with the balloon 3402 in a partially inflated state.
An annular inner lumen wall 3410 defines therein a drainage lumen
3412. At one or more circumferential longitudinal extents about the
inner lumen wall 3410, an inflation lumen wall 3420 defines an
inflation lumen 3422 and a balloon inflation port 3424 fluidically
connected to the inflation lumen 3422; in the inventive catheter,
there can be more than one inflation lumen 3422 and corresponding
inflation port 3424 even though only one is shown herein. No lumen
plug closes the inflation lumen 3422 distal of the inflation port
3424. In this exemplary embodiment, a stretch-valve mechanism 3430
serves to plug the inflation lumen 3422 distal of the inflation
port 3424 as described in further detail below. An outer wall 3440
covers all of the interior walls 3410 and 3420 in a fluid-tight
manner and forms the exterior of the balloon 3442 but does not
cover the distal end of the inflation lumen 3422. The outer wall
3440 is formed in any way described herein and is not discussed in
further detail here.
[0199] The stretch-valve mechanism 3430 is disposed in the
inflation lumen 3422 and does not hinder inflation of the balloon
3402 with inflating fluid. A proximal, hollow anchor portion 3432
is disposed in the inflation lumen 3420 proximal of the inflation
port 3424. While the diameter of the hollow anchor portion 3432 can
be any size that accommodates substantially unhindered fluid flow
through the inflation lumen 3422, one exemplary inner diameter of
the hollow anchor portion 3432 is substantially equal to the
diameter of the inflation lumen 3422 and the outer diameter of the
hollow anchor portion 3432 is just slightly larger than the
diameter of the inflation lumen 3422 (e.g., the wall thickness of
the tube can be between 0.05 mm and 0.2 mm). Another exemplary
embodiment of the hollow anchor portion 3432 and a stopper 3436 has
one or more of these larger in outer diameter than an intermediate
hollow stopper tube 3434. Thus, if one end is larger, the
stretch-valve mechanism 3430 has a "club" shape and, if both ends
are larger, the stretch-valve mechanism 3430 has a "dumbbell"
shape. An exemplary configuration of a dumbbell shaped
stretch-valve tube is described hereinbelow.
[0200] The longitudinal length of the hollow anchor portion 3432 is
as long as desired to be longitudinally fixedly secured within the
inflation lumen 3422 when installed in place. The tube, from its
shape alone, can provide the securing connection but, also, an
adhesive can be used in any manner, one of which includes creating
a proximal port as shown in the above embodiments and utilizing the
dipped exterior to form the fixed connection. The distal end of the
hollow anchor portion 3432 in this exemplary embodiment is at a
proximal side of the balloon 3402. The distal end of the hollow
anchor portion 3432 can be nearer to the inflation port 3424, but
not at or distal of the inflation port 3424; both ends of the
hollow anchor portion 3432 can be proximal, at, or distal to the
proximal end of the balloon 3402 and selection of this position is
dependent upon the amount of stretch that is desired to actuate the
stretch-valve of the inventive catheter 3400 as described below. In
the exemplary embodiment of FIG. 34, the intermediate hollow
stopper tube 3434 is connected at its proximal end to the hollow
anchor portion 3432 and the stopper 3436 is connected to the distal
end of the stopper tube 3434. The stopper tube 3434 is only a
circumferential portion of the hollow anchor portion 3432 and is
located opposite the inflation port 3424 so that it does not
obstruct fluid flow through the inflation port 3424. The stopper
3436, in contrast, is a solid cylinder having the same or different
outer diameter as the hollow anchor portion 3432. The entire
mechanism 3430 is sized to be slidably disposed in the inflation
lumen 3422 while, at the same time, to provide a fluid-tight seal
at the stopper 3436 so that liquid cannot pass from one side of the
stopper 3436 to the other side within the inflation lumen 3422. The
stopper 3436 is located distal of the inflation port 3424. The
stopper tube 3434, therefore, spans the inflation port 3424.
Because the stopper 3436 must traverse the inflation port 3424, it
must be just distal of the inflation port 3424 but the hollow
anchor portion 3432 can be located anywhere proximal of the
inflation port 3424. While the length of the stopper tube 3434
needs to be sufficient to span the inflation port 3424, it can be
as long as desired, which will depend on where the hollow anchor
portion 3432 resides. As the catheter 3400 stretches more at its
proximal end and less at its distal end when pulled from the
proximal end, the hollow anchor portion 3422 can be further
proximal in the inflation lumen 3422 than shown, and can even be
very close to or at the proximal end of the inflation lumen
3422.
[0201] In such a configuration, therefore, any proximal movement of
the catheter 3400 at or proximal to the inflation port 3424 will
also move the stretch-valve mechanism 3430 proximally; in other
words, the stopper 3436 slides proximally within the inflation
lumen 3422 from distal of the inflation port 3424 to a proximal
side of the inflation port 3424. When the proximal end of the
catheter 3400 is pulled to move the stopper 3436 across the
inflation port 3424 with a force that is no greater than just
before injury would occur to the bladder-urethral junction or the
urethra if the catheter 3400 was still inflated when the force was
imparted, fluid in the balloon 3442 can exit distally out the
inflation lumen 3422. In an exemplary embodiment of the stretch
valve of FIG. 34, a pulling force in a range of 1 to 15 pounds will
cause the stretch-valve mechanism 3430 to slide proximally to place
the stopper 3436 just proximal of the inflation port 3424, i.e.,
the deflation point of the stretch-valve shown in FIG. 34. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds. When the stopper 3436 traverses the
inflation port 3424, the balloon 3442 automatically deflates and
the inflating fluid exits into the bladder out the distal end of
the inflation lumen 3432, which is open at the distal end of the
catheter 3400.
[0202] FIG. 35 illustrates the balloon portion of the inventive
catheter 3500 with the balloon 3502 in a partially inflated state.
An annular inner lumen wall 3510 defines therein a drainage lumen
3512. At one or more circumferential longitudinal extents about the
inner lumen wall 3510, an inflation lumen wall 3520 defines an
inflation lumen 3522 and a balloon inflation port 3524 fluidically
connected to the inflation lumen 3522; in the inventive catheter,
there can be more than one inflation lumen 3522 and corresponding
inflation port 3524 even though only one is shown herein. No lumen
plug closes the inflation lumen 3522 distal of the inflation port
3524. In this exemplary embodiment, a stretch-valve mechanism 3530
serves to plug the inflation lumen 3522 distal of the inflation
port 3524 as described in further detail below. An outer wall 3540
covers all of the interior walls 3510 and 3520 in a fluid-tight
manner and forms the exterior of the balloon 3542 but does not
cover the distal end of the inflation lumen 3522. The outer wall
3540 is formed in any way described herein and is not discussed in
further detail here.
[0203] The stretch-valve mechanism 3530 is disposed in the
inflation lumen 3522 to not hinder inflation of the balloon 3502
with inflating fluid. A proximal, hollow anchor portion 3532 is
disposed in the inflation lumen 3520 proximal of the inflation port
3524. While the diameter of the hollow anchor portion 3532 can be
any size that accommodates substantially unhindered fluid flow
through the inflation lumen 3522, one exemplary inner diameter of
the hollow anchor portion 3532 is substantially equal to the
diameter of the inflation lumen 3522 and the outer diameter of the
hollow anchor portion 3532 is just slightly larger than the
diameter of the inflation lumen 3522 (e.g., the wall thickness of
the tube can be between 0.05 mm and 0.2 mm). Another exemplary
embodiment of the hollow anchor portion 3532 and a stopper 3536 has
one or more of these larger in outer diameter than an intermediate
bias device 3534. Thus, if one end is larger, the stretch-valve
mechanism 3430 has a "club" shape and, if both ends are larger, the
stretch-valve mechanism 3430 has a "dumbbell" shape. An exemplary
configuration of a dumbbell shaped stretch-valve tube is described
hereinbelow.
[0204] The longitudinal length of the hollow anchor portion 3532 is
as long as desired to be longitudinally fixedly secured within the
inflation lumen 3522 when installed in place. The tube, from its
shape alone, can provide the securing connection but, also, an
adhesive can be used in any manner, one of which includes creating
a proximal port as shown in the above embodiments and utilizing the
dipped exterior to form the fixed connection. The distal end of the
hollow anchor portion 3532 in this exemplary embodiment is at a
proximal side of the balloon 3502. The distal end of the
stretch-valve mechanism 3530 can be nearer to the inflation port
3524, but not at or distal of the inflation port 3524; both ends of
the hollow anchor portion 3532 can be proximal, at, or distal to
the proximal end of the balloon 3502 and selection of this position
is dependent upon the amount of stretch that is desired to actuate
the stretch-valve of the inventive catheter 3500 as described
below. In the exemplary embodiment of FIG. 35, the intermediate
bias device 3534, such as a spring, is connected at its proximal
end to the hollow anchor portion 3532 and the stopper 3536 is
connected to the distal end of the bias device 3534. The bias
device 3534 is located at the inflation port 3524 but not to
obstruct fluid flow through the inflation port 3524. The stopper
3536, in contrast, is a solid cylinder having the same outer
diameter as the hollow anchor portion 3532. The entire mechanism
3530 is sized to be slidably disposed in the inflation lumen 3522
while, at the same time, to provide a fluid-tight seal at the
stopper 3536 so that liquid cannot pass from one side of the
stopper 3536 to the other side within the inflation lumen 3522. The
stopper 3536 is located distal of the inflation port 3524. To
prevent distal movement of the stopper 3536, a restrictor 3538 is
provided distal of the stopper 3536. The bias device 3534,
therefore, spans the inflation port 3524. Because the stopper 3536
must traverse the inflation port 3524, it must be just distal of
the inflation port 3524 but the hollow anchor portion 3532 can be
located anywhere proximal of the inflation port 3524. While the
length of the bias device 3534 needs to be sufficient to span the
inflation port 3524, it can be as long as desired, which will
depend on where the hollow anchor portion 3532 resides. As the
catheter 3500 stretches more at its proximal end and less at its
distal end when pulled from the proximal end, the hollow anchor
portion 3522 can be further proximal in the inflation lumen 3522
than shown, and can even be very close to or at the proximal end of
the inflation lumen 3522.
[0205] In such a configuration, therefore, any proximal movement of
the catheter 3500 at or proximal to the inflation port 3524 will
also move the stretch-valve mechanism 3530 proximally; in other
words, the stopper 3536 slides proximally within the inflation
lumen 3522 from distal of the inflation port 3524 to a proximal
side of the inflation port 3524. When the proximal end of the
catheter 3500 is pulled to move the stopper 3536 across the
inflation port 3524 with a force that is no greater than just
before injury would occur to the bladder-urethral junction or the
urethra if the catheter 3500 was still inflated when the force was
imparted, fluid in the balloon 3542 can exit distally out the
inflation lumen 3522. In an exemplary embodiment of the stretch
valve of FIG. 35, a pulling force in a range of 1 to 15 pounds will
cause the stretch-valve mechanism 3530 to slide proximally to place
the stopper 3536 just proximal of the inflation port 3524, i.e.,
the deflation point of the stretch-valve shown in FIG. 35. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds. When the stopper 3536 traverses the
inflation port 3524, the balloon 3542 automatically deflates and
the inflating fluid exits into the bladder out the distal end of
the inflation lumen 3532, which is open at the distal end of the
catheter 3500.
[0206] FIG. 36 illustrates the balloon portion of the inventive
catheter 3600 with the balloon 3602 in a partially inflated state.
An annular inner lumen wall 3610 defines therein a drainage lumen
3612. At one or more circumferential longitudinal extents about the
inner lumen wall 3610, an inflation lumen wall 3620 defines an
inflation lumen 3622 and a balloon inflation port 3624 fluidically
connected to the inflation lumen 3622; in the inventive catheter,
there can be more than one inflation lumen 3622 and corresponding
inflation port 3624 even though only one is shown herein. No lumen
plug closes the inflation lumen 3622 distal of the inflation port
3624. In this exemplary embodiment, a stretch-valve mechanism 3630
serves to plug the inflation lumen 3622 distal of the inflation
port 3624 as described in further detail below. An outer wall 3640
covers all of the interior walls 3610 and 3620 in a fluid-tight
manner and forms the exterior of the balloon 3642 but does not
cover the distal end of the inflation lumen 3622. The outer wall
3640 is formed in any way described herein and is not discussed in
further detail here.
[0207] The stretch-valve mechanism 3630 is disposed in the
inflation lumen 3622 to not hinder inflation of the balloon 3602
with inflating fluid. A non-illustrated proximal anchor is disposed
in the inflation lumen 3620 proximal of the inflation port 3624.
The proximal anchor can be any size or shape that accommodates
substantially unhindered fluid flow through the inflation lumen
3622, one exemplary inner diameter of the hollow anchor portion is
a tube substantially equal to the diameter of the inflation lumen
3622 with an outer diameter just slightly larger than the diameter
of the inflation lumen 3622 (e.g., the thickness of the tube can be
between 0.07 mm and 0.7 mm). The longitudinal length of this hollow
anchor can be as long as desired to be longitudinally fixedly
secured within the inflation lumen 3622 when installed in place.
The anchor in this exemplary embodiment is at or near the
non-illustrated proximal end of the inflation lumen 3622. The
distal end of the stretch-valve mechanism 3630 can be nearer to the
inflation port 3624, but not at or distal of the inflation port
3624; selection of the anchor's position is dependent upon the
amount of stretch that is desired to actuate the stretch-valve of
the inventive catheter 3600 as described below. In the exemplary
embodiment of FIG. 36, the stretch-valve mechanism 3630 also
includes an intermediate cord 3634, either inelastic or elastic,
connected at its proximal end to the anchor. A stopper 3636 is
connected to the distal end of the cord 3634. The cord 3634 is
located at the inflation port 3624 but not to obstruct fluid flow
through the inflation port 3624. The stopper 3636, in contrast, is
a solid cylinder having a diameter that allows it to slidably move
within the inflation lumen 3622 when the cord 3634 pulls it but, at
the same time, to provide a fluid-tight seal so that liquid cannot
pass from one side of the stopper 3636 to the other side within the
inflation lumen 3622. The stopper 3636 is located distal of the
inflation port 3624. To prevent distal movement of the stopper
3636, a restrictor 3638 is provided distal of the stopper 3636. The
cord 3634, therefore, spans the inflation port 3624. Because the
stopper 3636 must traverse the inflation port 3624, it must be just
distal of the inflation port 3624 but the anchor can be located
anywhere proximal of the inflation port 3624. While the length of
the cord 3634 needs to be sufficient to span the inflation port
3624, it can be as long as desired, which will depend on where the
anchor resides. As the catheter 3600 stretches more at its proximal
end and less at its distal end when pulled from the proximal end,
the anchor can be further proximal in the inflation lumen 3622 than
shown, and can even be very close to or at the proximal end of the
inflation lumen 3622. It can even be attached to the luer connector
half that prevents fluid from flowing out the proximal end of the
inflation lumen 3622.
[0208] In such a configuration, therefore, any proximal movement of
the catheter 3600 at the proximal end where the anchor resides will
also move the stretch-valve mechanism 3630 proximally; in other
words, the stopper 3636 slides proximally within the inflation
lumen 3622 from distal of the inflation port 3624 to a proximal
side of the inflation port 3624. When the proximal end of the
catheter 3600 is pulled to move the stopper 3636 across the
inflation port 3624 with a force that is no greater than just
before injury would occur to the bladder-urethral junction or the
urethra if the catheter 3600 was still inflated when the force was
imparted, fluid in the balloon 3642 can exit distally out the
inflation lumen 3622. In an exemplary embodiment of the stretch
valve of FIG. 36, a pulling force in a range of 1 to 15 pounds will
cause the stretch-valve mechanism 3630 to slide proximally to place
the stopper 3636 just proximal of the inflation port 3624, i.e.,
the deflation point of the stretch-valve shown in FIG. 36. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds. When the stopper 3636 traverses the
inflation port 3624, the balloon 3642 automatically deflates and
the inflating fluid exits into the bladder out the distal end of
the inflation lumen 3622, which is open at the distal end of the
catheter 3600.
[0209] An alternative exemplary embodiment combines the embodiments
of FIGS. 30 and 36 to tether the tube 2820 to the proximal end of
the catheter.
[0210] In each of the embodiments of FIGS. 33 to 36, deflation of
the balloon 3342, 3442, 3542, 3642 out through the inflation lumen
3322, 3422, 3522, 3622 can be enhanced by creating a separate
deflation port D between the stopper 3336, 3436, 3536, 3636 and the
drain lumen 3312, 3412, 3512, 3612 at the rest or steady state
position of the stopper 3336, 3436, 3536, 3636 (shown in FIGS. 33
to 36). In such a configuration, when the stopper 3336, 3436, 3536,
3636 moves downstream of the inflation port 3324, 3424, 3524, 3624,
not only will the inflation fluid exit the distal (upstream) end of
the inflation lumen 3322, 3422, 3522, 3622, but it will also exit
directly into the drain lumen 3312, 3412, 3512, 3612. It is noted
that, when the stopper 3336, 3436, 3536, 3636 moves only slightly
downstream but not at or past the inflation port 3324, 3424, 3524,
3624, the deflation port D will connect the drain lumen 3312, 3412,
3512, 3612 to the inflation lumen 3322, 3422, 3522, 3622
fluidically. This is not disadvantageous in these configurations
because these lumens will be connected already through the distal
ends thereof in the drainage organ (e.g., the bladder).
[0211] FIG. 37 illustrates the balloon portion of the inventive
catheter 3700 with the balloon 3742 in a partially inflated state.
An annular inner lumen wall 3710 defines therein a drainage lumen
3712. At one or more circumferential longitudinal extents about the
inner lumen wall 3710, an inflation lumen wall 3720 defines an
inflation lumen 3722 and a balloon inflation port 3724 fluidically
connected to the inflation lumen 3722; in the inventive catheter,
there can be more than one inflation lumen 3722 and corresponding
inflation port 3724 even though only one is shown herein. A lumen
plug 3736 fluidically closes the inflation lumen 3722 distal of the
inflation port 3724 so that all inflation fluid 3702 is directed
into the balloon 3742. The lumen plug 3736 can plug any point or
extent from the inflation port 3724 distally. An outer wall 3740
covers all of the interior walls 3710 and 3720 in a fluid-tight
manner and forms the exterior of the balloon 3742 but does not
cover the distal end of the drainage lumen 3712. The outer wall
3740 is formed in any way described herein and is not discussed in
further detail here.
[0212] In this exemplary embodiment, a hollow, stretch-valve tube
3730 is disposed in the drainage lumen 3712 to not hinder drainage
of the fluid to be drained (e.g., urine). While the diameter of the
stretch-valve tube 3730 can be any size that accommodates
substantially unhindered fluid flow through the drainage lumen
3712, one exemplary inner diameter of the stretch-valve tube 3730
is substantially equal to the diameter of the drainage lumen 3712
and the outer diameter of the stretch-valve tube 3730 is just
slightly larger than the diameter of the drainage lumen 3712 (e.g.,
the wall thickness of the tube can be between 0.07 mm and 0.7 mm).
Another exemplary embodiment of the stretch-valve tube 3730 has one
or more of the proximal and distal ends thereof larger in outer
diameter than an intermediate portion of the stretch-valve tube
3730. Thus, if one end is larger, the stretch-valve tube 3730 has a
"club" shape and, if both ends are larger, the stretch-valve tube
3730 has a "dumbbell" shape. An exemplary configuration of a
dumbbell shaped stretch-valve tube is described hereinbelow.
[0213] The proximal end of the stretch-valve tube 3730 in this
exemplary embodiment is proximal of a proximal end of a deflation
port 3760. The distal end of the stretch-valve tube 3730 is not
distal of the distal end of the balloon 3742 so that the balloon
3742 can be deflated; the distal end can be anywhere between the
two ends of the balloon 3742 but is shown in an intermediate
position in FIG. 37. The distal end of the stretch-valve tube 3730
is at a distance S distal of the deflation port 3760 and selection
of this distance S is dependent upon the amount of stretch required
to actuate the stretch-valve of the inventive catheter 3700 as
described below. In the exemplary embodiment of FIG. 37, the
longitudinal length of the deflation port 3760 is shown as less
than one half of the longitudinal length of the stretch-valve tube
3730. The deflation port 3760 is formed through the inner lumen
wall 3710 and the stretch-valve tube 3730 is positioned to overlap
at least the deflation port 3760. In this manner, a portion of the
outer surface of the distal end of the stretch-valve tube 3730
closes off the deflation port 3760 to prevent fluid communication
between the balloon 3742 and the drainage lumen 3712 through the
deflation port 3760.
[0214] Exemplary embodiments for securing the stretch-valve tube
3730 in the catheter 3700 include a proximal anchor 3732 in the
drainage lumen 3710 disposed away from the deflation port 3760,
here proximally. The proximal anchor 3732 can be any size or shape
that accommodates substantially unhindered fluid flow through the
drainage lumen 3712, one exemplary inner diameter of the hollow
anchor 3732 being a tube or ring substantially equal to the
diameter of the drainage lumen 3712 with an outer diameter just
slightly larger than the diameter of the drainage lumen 3712 (e.g.,
the thickness of the tube can be between 0.07 mm and 0.7 mm). The
longitudinal length of this hollow anchor 3732 can be as long as
desired but just enough to longitudinally fixedly secure the
stretch-valve tube 3730 within the drainage lumen 3712 when
installed in place. The anchor 3732 in this exemplary embodiment is
at the proximal end of the balloon 3742 but can be further inside
the balloon 3742 (distal) or entirely proximal of the balloon 3742.
In an exemplary embodiment, the anchor 3732 has a stepped distal
orifice that permits the proximal end of the stretch-valve tube
3730 to be, for example, press-fit therein for permanent
connection. In another exemplary embodiment, the anchor 3732 is an
adhesive or glue that fixes the proximal end of the stretch-valve
tube 3730 longitudinally in place within the drainage lumen 3712.
The adhesive can be the same material as any or all of the walls
3710, 3720, 3740 or it can be a different material. In an exemplary
non-illustrated embodiment where a fixation port or set of fixation
ports are formed through the inner wall 3710 proximal of the
proximal-most end of the balloon 3742 and about the proximal end of
the stretch-valve tube 3730, if the outer wall 3740 is formed by a
dipping of the interior parts into a liquid bath of the same
material as, for example, a dual lumen extrusion including the
inner wall 3710 and the inflation lumen wall 3720, then, when set,
the outer wall 3740 will be integral to both the inner wall 3710
and the inflation lumen wall 3720 and will be fixedly connected to
the stretch-valve tube 3730 through the fixation port(s). (Further
exemplary embodiments for securing the stretch-valve tube 3730 in
the catheter 3700 are described below with regard to FIGS. 48 and
49.)
[0215] In such a configuration, therefore, any proximal movement of
the catheter 3700 at or proximal to the deflation port 3760 will
also move the stretch-valve tube 3730 proximally; in other words,
the distal end of the stretch-valve tube 3730 can slide within the
drainage lumen 3712 in a proximal direction. When the proximal end
of the catheter 3700 is pulled to a force that is no greater than
just before injury would occur to the bladder-urethral junction or
to the urethra if the catheter 3700 was still inflated when the
force was imparted, the force will cause the stretch-valve tube
3730 to slide proximally and place the distal end of the
stretch-valve tube 3730 just proximal of the deflation port 3760,
e.g., with a pulling force in a range of 1 to 15 pounds. In another
exemplary embodiment, the range of force required to meet the
deflation point is between 1 and 5 pounds, in particular, between
1.5 and 2 pounds.
[0216] When the deflation point of the stretch-valve tube 3730
occurs, the interior of the balloon 3742 becomes fluidically
connected directly into the drainage lumen 3712 (which is open to
the interior of the bladder 2020 and to the non-illustrated,
proximal drain bag) and, due to the fact that the bladder is
relatively unpressurized as compared to the balloon 3742, all
internal pressure is released from the balloon 3742 to eject the
inflating fluid 3702 directly into the drainage lumen 3712, thereby
causing the balloon 3742 to deflate rapidly. Because there is no
intermediate structure between the balloon inflating fluid 3702 and
the drainage lumen 3712, the rate at which the balloon 3742
deflates is fast. One way to speed up deflation can be to shape the
deflation port 3760 in the form of a funnel outwardly expanding in
a direction from the outer wall 3740 towards the interior of the
catheter 3700. Another way to speed up deflation can be the
presence of two or more deflation ports 3760 about the
circumference of the inner lumen wall 3710 and/or an enlargement of
the cross-sectional area of the deflation port 3760.
[0217] FIG. 38 illustrates a balloon portion of the inventive
catheter 3800 with a balloon 3842 in a partially inflated state. An
annular inner lumen wall 3810 defines therein a drainage lumen
3812. At one or more circumferential longitudinal extents about the
inner lumen wall 3810, an inflation lumen wall 3820 defines an
inflation lumen 3822 and a balloon inflation port 3824 fluidically
connected to the inflation lumen 3822; in the inventive catheter,
there can be more than one inflation lumen 3822 and corresponding
inflation port 3824 even though only one is shown herein. A lumen
plug 3836 fluidically closes the inflation lumen 3822 distal of the
inflation port 3824 so that all inflation fluid 3802 is directed
into the balloon 3842. The lumen plug 3736 can plug any point or
extent from the inflation port 3724 distally. An outer wall 3840
covers all of the interior walls 3810 and 3820 in a fluid-tight
manner and forms the exterior of the balloon 3842 but does not
cover the distal end of the drainage lumen 3812. The outer wall
3840 is formed in any way described herein and is not discussed in
further detail here.
[0218] In this exemplary embodiment, a hollow, stretch-valve tube
3830 is disposed in the drainage lumen 3812 to not hinder drainage
of the fluid to be drained (e.g., urine). While the diameter of the
stretch-valve tube 3830 can be any size that accommodates
substantially unhindered fluid flow through the drainage lumen
3812, one exemplary inner diameter of the stretch-valve tube 3830
is substantially equal to the diameter of the drainage lumen 3812
and the outer diameter of the stretch-valve tube 3830 is just
slightly larger than the diameter of the drainage lumen 3812 (e.g.,
the wall thickness of the tube can be between 0.07 mm and 0.7 mm).
Another exemplary embodiment of the stretch-valve tube 3830 has one
or more of the proximal and distal ends thereof larger in outer
diameter than an intermediate portion of the stretch-valve tube
3830. Thus, if one end is larger, the stretch-valve tube 3830 has a
"club" shape and, if both ends are larger, the stretch-valve tube
3830 has a "dumbbell" shape. An exemplary configuration of a
dumbbell shaped stretch-valve tube is described hereinbelow.
[0219] The proximal end of the stretch-valve tube 3830 in this
exemplary embodiment is proximal of a proximal end of a deflation
port 3860. The longitudinal length of the deflation port 3860 is
not distal of the distal end of the balloon 3842 so that the
balloon 3842 can be deflated; the distal end can be anywhere
between the two ends of the balloon 3842 but is shown in an
intermediate position in FIG. 38. The distal end of the
stretch-valve tube 3830 is at a distance S distal of the deflation
port 3860 and selection of this distance S is dependent upon the
amount of stretch required to actuate the stretch-valve of the
inventive catheter 3800 as described below. In the exemplary
embodiment of FIG. 38, the longitudinal length of the deflation
port 3760 is shown as less than one half of the longitudinal length
of the stretch-valve tube 3830. The drainage port 3860 is formed
through the inner lumen wall 3810 and the stretch-valve tube 3830
is positioned to overlap at least the drainage port 3860. In this
manner, a portion of the outer surface of the distal end of the
stretch-valve tube 3830 closes off the drainage port 3860 to
prevent fluid communication between the balloon 3842 and the
drainage lumen 3812 through the drainage port 3860.
[0220] In this exemplary embodiment, in comparison to the
embodiment of FIG. 37, a second drainage port 3862 is provided in
the inner lumen wall 3810 aligned with the drainage port 3860, and
both drainage ports 3860, 3862 are aligned with the inflation port
3824. As such, when the stretch-valve tube 3830 moves proximally to
uncover the drainage ports 3860, 3862, inflation fluid 3802 from
inside the balloon 3842 exits from both the inflation port 3824 and
the drainage port 3860.
[0221] To secure the stretch-valve tube 3830 in the catheter 3800,
a proximal anchor 3832 is disposed in the drainage lumen 3810 away
from the deflation ports 3860, 3862, here proximally. The proximal
anchor 3832 can be any size or shape that accommodates
substantially unhindered fluid flow through the drainage lumen
3812, one exemplary inner diameter of the hollow anchor 3832 being
a tube or ring substantially equal to the diameter of the drainage
lumen 3812 with an outer diameter just slightly larger than the
diameter of the drainage lumen 3812 (e.g., the thickness of the
tube can be between 0.07 mm and 0.7 mm). The longitudinal length of
this hollow anchor 3832 can be as long as desired but just enough
to longitudinally fixedly secure the stretch-valve tube 3830 within
the drainage lumen 3812 when installed in place. The anchor 3832 in
this exemplary embodiment is at the proximal end of the balloon
3842 but can be further inside the balloon 3842 (distal) or
entirely proximal of the balloon 3842. In an exemplary embodiment,
the anchor 3832 has a stepped distal orifice that permits the
proximal end of the stretch-valve tube 3830 to be, for example,
press-fit therein for permanent connection. In another exemplary
embodiment, the anchor 3832 is an adhesive or glue that fixes the
proximal end of the stretch-valve tube 3830 longitudinally in place
within the drainage lumen 3812. The adhesive can be the same
material as any or all of the walls 3810, 3820, 3840 or it can be a
different material. In an exemplary non-illustrated embodiment
where a fixation port or set of fixation ports are formed through
the inner wall 3810 proximal of the proximal-most end of the
balloon 3842 and about the proximal end of the stretch-valve tube
3830, if the outer wall 3840 is formed by a dipping of the interior
parts into a liquid bath of the same material as, for example, a
dual lumen extrusion including the inner wall 3810 and the
inflation lumen wall 3820, then, when set, the outer wall 3840 will
be integral to both the inner wall 3810 and the inflation lumen
wall 3820 and will be fixedly connected to the stretch-valve tube
3820 through the fixation port(s). (Further exemplary embodiments
for securing the stretch-valve tube 3830 in the catheter 3800 are
described below with regard to FIGS. 48 and 49.)
[0222] In such a configuration, therefore, any proximal movement of
the catheter 3800 at or proximal to the drainage ports 3860, 3862
will also move the stretch-valve tube 3830 proximally; in other
words, the distal end of the stretch-valve tube 3830 can slide
within the drainage lumen 3812 in a proximal direction. When the
proximal end of the catheter 3800 is pulled to a force that is no
greater than just before injury would occur to the bladder-urethral
junction or the urethra if the catheter 3800 was still inflated
when the force was imparted, the force will cause the stretch-valve
tube 3830 to slide proximally to place the distal end of the
stretch-valve tube 3830 just proximal of the drainage ports 3860,
3862, e.g., with a pulling force in a range of 1 to 15 pounds. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds.
[0223] When the deflation point of the stretch-valve tube 3830
occurs, the interior of the balloon 3842 becomes fluidically
connected directly into the drainage lumen 3812 (which is open to
the interior of the bladder 2020 and to the non-illustrated,
proximal drain bag) and, due to the fact that the bladder is
relatively unpressurized as compared to the balloon 3842, all
internal pressure is released from the balloon 3842 to eject the
inflating fluid 3802 directly into the drainage lumen 3812, thereby
causing the balloon 3842 to deflate rapidly. Because there is no
intermediate structure between the balloon inflating fluid 3802 and
the drainage lumen 3812, the rate at which the balloon 3842
deflates is fast. One way to speed up deflation can be to shape the
drainage ports 3860, 3862 in the form of a funnel outwardly
expanding in a direction from the outer wall 3840 towards the
interior of the catheter 3800. Another way to speed up deflation
can be to have two or more drainage ports 3860 about the
circumference of the inner lumen wall 3810 and/or to enlarge the
cross-sectional area of the drainage ports 3860, 3862.
[0224] Reference is made to the flow chart of FIG. 39 to explain
one exemplary embodiment of a process for making a catheter
according to the embodiment of FIGS. 21 to 23.
[0225] The catheter starts, in Step 3910 with a dual lumen
extrusion of latex. This extrusion, therefore, defines the annular
inner lumen wall 2110 with the drainage lumen 2112 and, at one or
more circumferential longitudinal extents about the inner lumen
wall 2110, an inflation lumen wall 2120 with the inflation lumen
2122. The dual lumen, therefore, already includes both the drainage
lumen 2112 and the inflation lumen 2122. Both lumen 2112, 2122,
however, are extruded without obstruction and without radial ports.
Therefore, in order to have the inflation port 2124, a radial hole
needs to be created between the outside surface of the extrusion
and the inflation lumen.
[0226] In step 3912, the balloon inflation port 2124 is made to
fluidically connect the environment of the extrusion to the
inflation lumen 2122.
[0227] Sealing off of the distal end of the inflation lumen 2122
can be performed in Step 3914 by inserting or creating a plug 2126
therein or the sealing can occur simultaneously with the creation
of the outer wall 2140 below.
[0228] In step 3916, a balloon sleeve 2130 is placed about the
inflation port 2124 and is fixed to the exterior of the inflation
lumen wall 2120 at both ends to define a fluid-tight balloon
interior 2200 therebetween. As such, inflation of the balloon 2210
can occur through the inflation lumen 2122. For example, the tube
2130 making up the inner balloon wall is slid over the distal end
of the dual-lumen extrusion to cover the inflation port 2124 and is
fluid-tightly sealed to the inner multi-lumen extrusion at both
ends of the tube but not in the intermediate portion. This tube can
be made of latex as well and, therefore, can be secured to the
latex multi-lumen extrusion in any known way to bond latex in a
fluid-tight manner.
[0229] In step 3918, the entire sub-assembly is covered with the
outer wall 2140. For example, the entire sub-assembly is dipped
into latex in its liquid form to create the outer wall 2140. In the
alternative embodiment where a distal inflation lumen plug is not
used, the latex can be allowed to enter at least a portion of the
distal end of the inflation lumen 2122 but not so far as to block
the inflation port 2124. When the latex cures, the balloon 2210 is
fluid tight and can only be fluidically connected to the
environment through the proximal-most opening of the inflation
port, which is fluidically connected to the inflation lumen 2122.
In this process, the inner wall 2110, the inflation lumen wall
2120, the plug 2126, the balloon wall 2130, and the outer wall 2140
are all made of the same latex material and, therefore, together
form a very secure water-tight balloon 2210.
[0230] The sub-process described in Steps 3910 to 3920 can be
skipped if desired and, instead, completed by utilizing a standard
Foley catheter, on which the following steps are performed.
[0231] The stretch valve is now created. A proximal port 2150 is
formed through the outer wall 2140 and through the inflation lumen
wall 2020 in step 3920. A distal port 2160 is formed through the
outer wall 2140 and through the inflation lumen wall 2020 in step
3922. Then, in step 3924, the stretch-valve tube 2220 is inserted
through either one of the proximal or distal ports 2150, 2160 such
that the proximal port 2150 overlaps at least a portion of the
proximal end of the stretch-valve tube 2220 and the distal port
2160 overlaps at least a portion of the distal end of the
stretch-valve tube 2220. In this manner, two portions of the outer
surface of the proximal end of the stretch-valve tube 2220 at the
proximal and distal ports 2150, 2160 are exposed to the environment
but there is no fluid communication with the inflation lumen 2122
and the proximal or distal ports 2150, 2160.
[0232] In Step 3926, the proximal port 2150 is used to secure the
stretch-valve tube 2220 in the catheter 2100. In one exemplary
embodiment, the proximal port 2150 is filled with a material that
fixes the proximal end of the stretch-valve tube 2220 to at least
one of the outer wall 2140 and the inflation lumen wall 2020. In an
exemplary embodiment, an adhesive bonds the proximal end of the
stretch-valve tube 2220 to both the outer wall 2140 and the
inflation lumen wall 2120. In another exemplary embodiment, a
portion of the present sub-assembly is dipped into latex in its
liquid form to plug the proximal port 2150 and fixedly secure the
stretch-valve tube 2220 to both the outer wall 2140 and the
inflation lumen wall 2120. When the latex cures, the connection at
the proximal port 2150 is fluid tight and no longer permits fluidic
connection to the environment therethrough. In this process,
therefore, the filled proximal port 2150, the inflation lumen wall
2120, and the outer wall 2140 are all made of the same latex
material and, therefore, together form a very secure water-tight
connection. (Further exemplary embodiments for securing the
stretch-valve tube 2220 in the catheter 2100 are described below
with regard to FIGS. 48 and 49.)
[0233] In such a configuration, therefore, any proximal movement of
the catheter 2100 at or proximal of the proximal port 2150 will
also move the stretch-valve tube 2220 proximally; in other words,
the distal end of the stretch-valve tube 2220 can slide within the
inflation lumen 2122 in a proximal direction.
[0234] Reference is also made to the flow chart of FIG. 39 to
explain one exemplary embodiment of a process for making a catheter
according to the embodiment of FIGS. 24 to 26.
[0235] The catheter starts, in Step 3910 with a dual lumen
extrusion of latex. This extrusion, therefore, defines the annular
inner lumen wall 2410 with the drainage lumen 2412 and, at one or
more circumferential longitudinal extents about the inner lumen
wall 2410, an inflation lumen wall 2420 with the inflation lumen
2422. The dual lumen, therefore, already includes both the drainage
lumen 2412 and the inflation lumen 2422. Both lumens 2412, 2422,
however, are extruded without obstruction and without radial ports.
Therefore, in order to have the inflation port 2424, a radial hole
needs to be created between the outside surface of the extrusion
and the inflation lumen.
[0236] In Step 3912, the balloon inflation port 2424 is made to
fluidically connect the environment of the extrusion to the
inflation lumen 2422.
[0237] Sealing off of the distal end of the inflation lumen 2422
can be performed in Step 3914 by inserting or creating a plug 2426
therein or the sealing can occur simultaneously with the creation
of the outer wall 2440 below.
[0238] In Step 3916, a balloon sleeve 2430 is placed about the
inflation port 2424 and is fixed to the exterior of the inflation
lumen wall 2420 at both ends to define a fluid-tight balloon
interior 2200 therebetween. As such, inflation of the balloon 2240
can occur through the inflation lumen 2422. For example, the tube
2430 making up the inner balloon wall is slid over the distal end
of the dual-lumen extrusion to cover the inflation port 2424 and is
fluid-tightly sealed to the inner multi-lumen extrusion at both
ends of the tube but not in the intermediate portion. This tube can
be made of latex as well and, therefore, can be secured to the
latex multi-lumen extrusion in any known way to bond latex in a
fluid-tight manner.
[0239] In Step 3918, the entire sub-assembly is covered with the
outer wall 2440. For example, the entire sub-assembly is dipped
into latex in its liquid form to create the outer wall 2440. In the
alternative embodiment where a distal inflation lumen plug is not
used, the latex can be allowed to enter at least a portion of the
distal end of the inflation lumen 2422 but not so far as to block
the inflation port 2424. When the latex cures, the balloon 2240 is
fluid tight and can only be fluidically connected to the
environment through the proximal-most opening of the inflation
port, which is fluidically connected to the inflation lumen 2422.
In this process, the inner wall 2410, the inflation lumen wall
2420, the plug 2426, the balloon wall 2430, and the outer wall 2440
are all made of the same latex material and, therefore, together
form a very secure water-tight balloon 2240.
[0240] The sub-process described in Steps 3910 to 3920 can be
skipped if desired and, instead, completed by utilizing a standard
Foley catheter, on which the following Steps are performed.
[0241] The stretch valve is now created. A proximal port 2450 is
formed through the outer wall 2440 and through the inflation lumen
wall 2020 in Step 3920. A distal port 2460 is formed through the
inner wall 2410 into the inflation lumen 2422 in Step 3922. Then,
in Step 3924, the stretch-valve tube 2520 is inserted through
either one of the proximal or distal ports 2450, 2460 such that the
proximal port 2450 overlaps at least a portion of the proximal end
of the stretch-valve tube 2520 and the distal port 2460 overlaps at
least a portion of the distal end of the stretch-valve tube 2520.
In this manner, one portion of the outer surface of the proximal
end of the stretch-valve tube 2520 at the proximal port 2450 is
exposed to the drain lumen 2412 and another portion of the outer
surface of the distal end of the stretch-valve tube 2520 at the
distal port 2460 is exposed to the environment but there is no
fluid communication with the inflation lumen 2422 to either of the
proximal or distal ports 2450, 2460.
[0242] In Step 3926, the proximal port 2450 is used to secure the
stretch-valve tube 2520 in the catheter 2400. In one exemplary
embodiment, the proximal port 2450 is filled with a material that
fixes the proximal end of the stretch-valve tube 2520 to at least
one of the outer wall 2440 and the inflation lumen wall 2020. In an
exemplary embodiment, an adhesive bonds the proximal end of the
stretch-valve tube 2520 to both the outer wall 2440 and the
inflation lumen wall 2420. In another exemplary embodiment, a
portion of the present sub-assembly is dipped into latex in its
liquid form to plug the proximal port 2450 and fixedly secure the
stretch-valve tube 2520 to both the outer wall 2440 and the
inflation lumen wall 2420. When the latex cures, the connection at
the proximal port 2450 is fluid tight and no longer permits fluidic
connection to the environment therethrough. In this process,
therefore, the filled proximal port 2450, the inflation lumen wall
2420, and the outer wall 2440 are all made of the same latex
material and, therefore, together form a very secure water-tight
connection. (Further exemplary embodiments for securing the
stretch-valve tube 2520 in the catheter 2400 are described below
with regard to FIGS. 48 and 49.)
[0243] In such a configuration, therefore, any proximal movement of
the catheter 2400 at or proximal of the proximal port 2450 will
also move the stretch-valve tube 2520 proximally; in other words,
the distal end of the stretch-valve tube 2520 can slide within the
inflation lumen 2422 in a proximal direction.
[0244] Reference is made to the flow chart of FIG. 40 to explain
one exemplary embodiment of a process for making a catheter
according to the embodiment of FIGS. 27 to 29.
[0245] The catheter starts, in Step 4010 with a dual lumen
extrusion of latex. This extrusion, therefore, defines the annular
inner lumen wall 2710 with the drainage lumen 2712 and, at one or
more circumferential longitudinal extents about the inner lumen
wall 2710, an inflation lumen wall 2720 with the inflation lumen
2722. The dual lumen, therefore, already includes both the drainage
lumen 2712 and the inflation lumen 2722. Both lumen 2712, 2722,
however, are extruded without obstruction and without radial ports.
Therefore, in order to have the inflation port 2724, a radial hole
needs to be created between the outside surface of the extrusion
and the inflation lumen.
[0246] In Step 4012, the balloon inflation port 2724 is made to
fluidically connect the environment of the extrusion to the
inflation lumen 2722.
[0247] Different from the other exemplary embodiments described, a
distal port 2760 is created in Step 4014 before, after, or at the
same time as the balloon inflation port 2724. The distal port 2760
connects the environment to the interior of the drain lumen 2712.
In an exemplary embodiment, the distal port 2760 is proximal of the
balloon inflation port 2724.
[0248] Sealing off of the distal end of the inflation lumen 2722
can be performed in Step 4016 by inserting or creating a plug 2726
therein or the sealing can occur simultaneously with the creation
of the outer wall 2740 below.
[0249] In Step 4018, a balloon sleeve 2730 is placed about the
inflation port 2724 and the distal port 2760 and is fixed to the
exterior of the inflation lumen wall 2720 at both ends to define a
fluid-tight balloon interior 2200 therebetween. As such, inflation
of the balloon 2810 can occur through the inflation lumen 2722. For
example, the tube 2730 making up the inner balloon wall is slid
over the distal end of the dual-lumen extrusion to cover the
inflation port 2724 and is fluid-tightly sealed to the inner
multi-lumen extrusion at both ends of the tube but not in the
intermediate portion. This tube can be made of latex as well and,
therefore, can be secured to the latex multi-lumen extrusion in any
known way to bond latex in a fluid-tight manner.
[0250] Installation of the stretch valve occurs by forming a
proximal port 2750 through the inflation lumen wall 2020 in Step
4020. Then, in Step 4022, the stretch-valve tube 2820 is inserted
through either one of the proximal or distal ports 2750, 2760 such
that the proximal port 2750 overlaps at least a portion of the
proximal end of the stretch-valve tube 2820 and the distal port
2760 overlaps at least a portion of the distal end of the
stretch-valve tube 2820. In this manner, two portions of the outer
surface of the proximal end of the stretch-valve tube 2820 at the
proximal and distal ports 2750, 2760 are exposed to the environment
but there is no fluid communication with the inflation lumen 2722
and the proximal or distal ports 2750, 2760. Alternatively, Steps
4022 can occur before 4018 to insert the stretch-valve tube 2820
before the balloon sleeve 2730 is placed and fixed. In such a case,
the creation of the proximal port 2750 can occur before, after, or
at the same time as creating the distal port 2760 and the balloon
inflation port 2724, in which embodiment, all three ports 2724,
2750, 2760 can be created at the same time.
[0251] In Step 4024, the entire sub-assembly is covered with the
outer wall 2740. For example, the entire sub-assembly is dipped
into latex in its liquid form to create the outer wall 2740. In the
alternative embodiment where a distal inflation lumen plug is not
used, the latex can be allowed to enter at least a portion of the
distal end of the inflation lumen 2722 but not so far as to block
the inflation port 2724. When the latex cures, the balloon 2810 is
fluid tight and can only be fluidically connected to the
environment through the proximal-most opening of the inflation
port, which is fluidically connected to the inflation lumen 2722.
In this process, the inner wall 2710, the inflation lumen wall
2720, the plug 2726, the balloon wall 2730, and the outer wall 2740
are all made of the same latex material and, therefore, together
form a very secure water-tight balloon 2810.
[0252] In previous embodiments, the proximal port 2750 pierced the
outer wall 2740. In this exemplary embodiment, however, there is no
need to do so. Here, the proximal port 2750 can be filled with
material of the outer wall 2740 itself to fix the proximal end of
the stretch-valve tube 2820 to at least one of the outer wall 2740
and the inflation lumen wall 2020. When the latex cures, the
connection at the proximal port 2750 is fluid tight and no longer
permits fluidic connection to the environment therethrough. In this
process, therefore, the filled proximal port 2750, the inflation
lumen wall 2720, and the outer wall 2740 are all made of the same
latex material and, therefore, together, form a very secure
water-tight connection. In an alternative exemplary embodiment, an
adhesive can be used to bond the proximal end of the stretch-valve
tube 2820 to the inflation lumen wall 2720. (Further exemplary
embodiments for securing the stretch-valve tube 2820 in the
catheter 2700 are described below with regard to FIGS. 48 and
49.)
[0253] In such a configuration, therefore, any proximal movement of
the catheter 2700 at or proximal of the proximal port 2750 will
also move the stretch-valve tube 2820 proximally; in other words,
the distal end of the stretch-valve tube 2820 can slide within the
inflation lumen 2722 in a proximal direction.
[0254] Reference is made to the flow chart of FIG. 41 to explain
one exemplary embodiment of a process for making a catheter
according to the embodiment of FIGS. 37 and 38.
[0255] The catheter starts, in Step 4110 with a dual lumen
extrusion of latex. This extrusion, therefore, defines the annular
inner lumen wall 3710, 3810 with the drainage lumen 3712, 3812 and,
at one or more circumferential longitudinal extents about the inner
lumen wall 3710, 3810, an inflation lumen wall 3720, 3820 with the
inflation lumen 3722, 3822. The dual lumen, therefore, already
includes both the drainage lumen 2712, 2812 and the inflation lumen
2722, 2822. Both lumen 2712, 2722, 2812, 2822, however, are
extruded without obstruction and without radial ports. Therefore,
in order to have the inflation port 3724, 3824, a radial hole needs
to be created between the outside surface of the extrusion and the
inflation lumen.
[0256] In Step 4112, the balloon inflation port 3724, 3824 is made
to fluidically connect the environment of the extrusion to the
inflation lumen 3722, 3822.
[0257] Different from the other exemplary embodiments described,
with regard to the embodiment of FIG. 37, the deflation port 3760
is created in Step 4114 before, after, or at the same time as the
balloon inflation port 3724. The deflation port 3760 connects the
interior of the balloon 3742 to the interior of the drain lumen
3712. In an exemplary embodiment, the deflation port 3760 is
proximal of the balloon inflation port 3724 but can be at or distal
thereof.
[0258] Different from the other exemplary embodiments described,
with regard to the embodiment of FIG. 38, the drainage ports 3860
and 3862 are created in Step 4114 before, after, or at the same
time as the balloon inflation port 3824. The drainage port 3860
connects the interior of the balloon 3842 to the interior of the
drain lumen 2712 and the drainage port 3862 connects the interior
of the inflation lumen 3822 to the interior of the drain lumen
2712. In an exemplary embodiment, the drainage ports 3860, 3862 are
aligned with the balloon inflation port 3824 but they can be distal
or proximal thereof. When aligned, a single through-hole can be
made through the entire catheter, penetrating both the inflation
and drainage channels 3712, 3722, 3812, 3822 and both walls 3710,
3720, 3810, 3820 of the dual lumen extrusion. Alternatively, the
drainage ports 3860, 3862 can be spaced from one another with
either one or neither aligned with the inflation port 3824.
[0259] In Step 4116, a fixation point 3732, 3832 is established at
the outer wall 3710, 3810. At this fixation point 3732, 3832 are
the measures for fixing the stretch-valve tube 3730, 3830 inside
the drainage lumen 3712, 3812. The fixation point 3732, 3832 can be
placed anywhere proximal of the drainage ports 3760, 3860, 3862.
The fixation point 3732, 3832 is not aligned circumferentially with
the inflation port 3724, 3824 as shown in FIGS. 37 and 38. In the
exemplary embodiment shown, the fixation point 3732, 3832 is still
within the proximal end of the balloon 3742, 3842 but it can
equally be further proximal of the balloon 3742, 3842 to any point
proximal within the drainage lumen 3712, 3812.
[0260] Sealing off of the distal end of the inflation lumen 3722,
3822 can be performed in Step 4118 by inserting or creating a plug
3736, 3836 therein or the sealing can occur before forming the
fixation ports or just before or simultaneously with the creation
of the outer wall 3740, 3840 below in Step 4124.
[0261] In Step 4120, the stretch-valve tube 3730, 3830 is inserted
into the drainage lumen 3712, 3812 and aligned so that the
stretch-valve tube 3730, 3830 covers all drainage ports 3760, 3860,
3862. The distal end of the stretch-valve tube 3730, 3830 is
positioned at the distal distance S desired for operation of the
stretch valve. For example, the distance can be up to 1 mm, up to 2
mm, up to 3 mm and up to even 1 or 2 cm. The distance S can also be
dependent on the amount of stretch at the proximal end of the
catheter as the displacement of the stretch-valve tube is
proportional to the stretch of the catheter. For example, if the
catheter is 500 mm long and is pulled 20%, then it will be 600 mm
long (a 100 mm stretch). A 10 mm or longer stretch-valve tube made
from a stiff material, such as metal (e.g., stainless steel,
titanium, etc.) polycarbonate, polyimide, polyamide, polyurethane
(Shore 55D-75D), and the like, located near the balloon of the
catheter has its proximal end glued to the inside of the inflation
or drainage lumen. When this catheter is stretched than 20%, then
the distal tip of a 10 mm stretch valve will move 2 mm in the
proximal direction. Accordingly, if the drainage port(s) is placed
2 mm proximal to the distal end of the stretch-valve tube (here,
S=2 mm), it will remain sealed by the stretch-valve tube at a
stretch of about 20%. But, when the catheter is pulled slightly
more than 20% (or 2 mm), the drainage port will unseal and the
inflation fluid within the balloon will discharge out the drainage
port. As catheters vary among manufacturers, calibration of the
percent stretch to the force required to stretch the catheter can
be done for each different type of catheter. This force is defined
in engineering terms as a modulus of the catheter and is a function
of the modulus of the material and the effective wall thickness of
the catheter. Low modulus materials and catheters will stretch more
than high modulus materials and catheters when exposed to the same
force. Exemplary catheters are those made from latex rubber or
silicone rubber. Silicone rubber generally has a higher modulus
than latex and, therefore, more force is required to stretch the
catheter sufficiently to discharge the pressure within the balloon.
Those of skill in the art, therefore, will understand that
different stretch valves lengths can provided to dump the balloon
pressure as a function of a tug-force on the different catheters
made from the different materials and having different wall
thicknesses. Accordingly, even though the stretch-valve tube
distances are given, they are exemplary and can change for
different catheters having different materials/thicknesses. As
such, these exemplary distances for actuating the stretch-valve
tube applies to all embodiments described herein but are not
limited thereto.
[0262] If fixation through-holes 3732, 3832 exist and are within
the inflation expanse of the balloon sleeve (not illustrated), then
an adhesive can be used within the fixation through-holes 3732,
3832 to fix the proximal end of the stretch-valve tube 3730, 3830
thereat before attachment of the balloon sleeve. If the fixation
through-holes 3732, 3832 are within the expanse of the balloon
sleeve but only overlap at the fixed proximal end of the balloon
sleeve (not illustrated), then the same adhesive that fixes the
proximal end of the balloon sleeve can be used within the fixation
through-holes 3732, 3832 to fix the proximal end of the
stretch-valve tube 3730, 3830 thereat. Finally, if the fixation
through-holes 3732, 3832 are outside the expanse of the balloon
sleeve proximally (not illustrated), then an adhesive or the same
material that creates the outer wall 3740, 3840 (see below) can be
used within the fixation through-holes 3732, 3832 to fix the
proximal end of the stretch-valve tube 3730, 3830.
[0263] In Step 4122, the balloon sleeve is placed about the
inflation port 3724, 3824 and, if present, fixation through-holes
3732, 3832 and the balloon sleeve is fixed to the exterior of the
inner and inflation lumen walls 3710, 3720, 3810, 3820 at both ends
to define a fluid-tight balloon interior therebetween. As such,
inflation of the balloon 3742, 3842 can occur through the inflation
lumen 3722, 3822. For example, the balloon sleeve making up the
inner wall of the balloon 3742, 3842 is slid over the distal end of
the dual-lumen extrusion to cover at least the inflation port 3724,
3824 and is fluid-tightly sealed to the inner multi-lumen extrusion
at both ends of the balloon sleeve but not in the intermediate
portion. The balloon sleeve can be made of latex as well and,
therefore, can be secured to the latex multi-lumen extrusion in any
known way to bond latex in a fluid-tight manner.
[0264] In Step 4124, the entire sub-assembly is covered with the
outer wall 3740, 3840. For example, the entire sub-assembly is
dipped into latex in its liquid form to create the outer wall 3740,
3840. In the alternative embodiment where a distal inflation lumen
plug 3736, 3836 is not used, the latex can be allowed to enter at
least a portion of the distal end of the inflation lumen 3722, 3822
but not so far as to block the inflation port 3724, 3824. When the
latex cures, the balloon 3742, 3842 is fluid tight and can only be
fluidically connected to the environment through the proximal-most
opening of the inflation port, which is fluidically connected to
the inflation lumen 3722, 3822. In this process, the inner wall
3710, 3810, the inflation lumen wall 3720, 3820, the plug 3736,
3836, the balloon wall, and the outer wall 3740, 3840 are all made
of the same latex material and, therefore, together form a very
secure water-tight balloon 3742, 3842. (Further exemplary
embodiments for securing the stretch-valve tube 3730, 3830 in the
catheter 3700, 3800 are described below with regard to FIGS. 48 and
49.)
[0265] In such configurations, therefore, any proximal movement of
the catheter 3700, 3800 at or proximal of the proximal anchor 3732,
3832 will also move the stretch-valve tube 3730, 3830 proximally;
in other words, the distal end of the stretch-valve tube 3730, 3830
can slide within the inflation lumen 3722, 3822 in a proximal
direction.
[0266] The steps outlined above in the exemplary embodiments need
not be done in the order described or illustrated. Any of these
steps can occur in any order to create the catheter according to
the various exemplary embodiments.
[0267] FIGS. 42 and 43 illustrate the balloon portion of other
exemplary embodiments of the inventive catheter 4200, 4300, again
with the balloon 3842 in a partially inflated state. In these
exemplary embodiments, most of the features are the same as the
catheter 3800 shown in FIG. 38, as well as in the other exemplary
embodiments of the safety catheters described herein. What is
different in FIGS. 42 and 43 is how the stretch valve operates and,
therefore, the similar features use the same reference numerals as
in FIG. 38. Different features, however, use new reference
numerals. Thus, description of the similar features is not repeated
below and is, instead, incorporated herein by reference from the
above-mentioned exemplary embodiments.
[0268] In the catheters 4200, 4300, the annular inner lumen wall
4210, 4310 defines therein a drainage lumen 4212, 4312. In this
exemplary embodiment, a hollow stretch-valve tube 3830 is disposed
in the drainage lumen 4212, 4312 to not hinder drainage of the
fluid to be drained (e.g., urine). While the diameter of the
stretch-valve tube 3830 can be any size that accommodates
substantially unhindered fluid flow through the drainage lumen
4212, 4312, one exemplary inner diameter of the stretch-valve tube
3830 is substantially equal to the diameter of the drainage lumen
4212, 4312 and the outer diameter of the stretch-valve tube 3830 is
just slightly larger than the diameter of the drainage lumen 4212,
4312 (e.g., the wall thickness of the tube can be between 0.07 mm
and 0.7 mm). (In any embodiment of the stretch-valve tube mentioned
herein, the outer diameter can be equal to or less than the
diameter of the drainage lumen.) Another exemplary embodiment of
the stretch-valve tube 3830, 4330 has one or more of the proximal
and distal ends thereof larger in outer diameter than an
intermediate portion of the stretch-valve tube 3830, 4330. Thus, if
one end is larger, the stretch-valve tube 3830, 4330 has a "club"
shape and, if both ends are larger, the stretch-valve tube 3830,
4330 has a "dumbbell" shape. An exemplary configuration of a
dumbbell shaped stretch-valve tube is described hereinbelow.
[0269] The proximal end of the stretch-valve tube 3830 in this
exemplary embodiment is proximal of a proximal end of a deflation
port 3860. The longitudinal length of the deflation port 3860 is
not distal of the distal end of the balloon 3842 so that the
balloon 3842 can be deflated; the distal end can be anywhere
between the two ends of the balloon 3842 but is shown in an
intermediate position in FIGS. 42 and 43. The distal end of the
stretch-valve tube 3830 is at a distance S distal of the deflation
port 3860 and selection of this distance S is dependent upon the
amount of stretch required to actuate the stretch-valve of the
inventive catheter 4200, 4300 as described herein.
[0270] In the exemplary embodiments of FIGS. 38, 42 and 43, the
longitudinal length of the deflation port 3860 is shown as less
than one half of the longitudinal length of the stretch-valve tube
3830. The drainage port 3860 is formed through the inner lumen wall
3810 and the stretch-valve tube 3830 is positioned to overlap at
least the drainage port 3860. In this manner, a portion of the
outer surface of the proximal end of the stretch-valve tube 3830
closes off the drainage port 3860 to prevent fluid communication
from the balloon 3842 to the drainage lumen 4212, 4312 through the
drainage port 3860. A second drainage port 3862 is provided in the
inner lumen wall 3810 aligned with the drainage port 3860, and both
drainage ports 3860, 3862 are aligned with the inflation port 3824.
As such, when the stretch-valve tube 3830 moves proximally to
uncover the drainage ports 3860, 3862, inflation fluid 3802 from
inside the balloon 3842 exits from both the inflation port 3824 and
the drainage port 3860.
[0271] To secure the stretch-valve tube 3830 in the catheter 4200,
4300, a proximal anchor 4232, 4332 is disposed in the drainage
lumen 4212 away from the deflation ports 3860, 3862, here
proximally at a distance E in FIG. 42 and at a longer distance F in
FIG. 43. The distances shown are not the only sizes for the
stretch-valve tube 3830 and can be shorter or longer, the latter
extending well into the drainage lumen 4212, 4312 proximally even
further than shown in FIG. 43. The proximal anchor 3832 can be any
size or shape that accommodates substantially unhindered fluid flow
through the drainage lumen 4212, 4312, one exemplary inner diameter
of the hollow anchor 3832 being a tube or ring substantially equal
to the diameter of the drainage lumen 4212 with an outer diameter
just slightly larger than the diameter of the drainage lumen 4212
(e.g., the thickness of the tube can be between 0.07 mm and 0.7
mm). The proximal anchor 3832 can be a barb or other mechanical
fixation device as well, whether integral or connected to the
stretch-valve tube 3830. The longitudinal length of this anchor
3832 can be as long as desired but enough to longitudinally fixedly
secure the proximal end of the stretch-valve tube 3830 within the
drainage lumen 4212 when installed in place. The anchor 3832 in
this exemplary embodiment is at the proximal end of the balloon
3842 as shown in FIG. 42 but it can be further inside the balloon
3842 (i.e., distal with regard to FIG. 42) or entirely proximal of
the balloon 3842 as shown in FIG. 43. The further proximal that the
anchor 3832 is connected within the drainage lumen 4212, 4312, the
greater the distance of stretching material is disposed between the
anchor 3832 and the drainage ports 3860, 3862, thereby enhancing
the ability of the safety catheter to stretch and activate the
stretch-valve. (Further exemplary embodiments for securing the
stretch-valve tube 3830, 4330 in the catheter 4200, 4300 are
described below with regard to FIGS. 48 and 49.)
[0272] In such configurations, therefore, any proximal movement of
the catheter 4200, 4300 at or proximal to the drainage ports 3860,
3862 will also move the stretch-valve tube 3830 proximally; in
other words, the distal end of the stretch-valve tube 3830 can
slide within the drainage lumen 4212 in a proximal direction. When
the proximal end of the catheter 4200, 4300 is pulled to a force
that is no greater than just before injury would occur to the
bladder-urethral junction or the urethra if the catheter 4200, 4300
was still inflated when the force was imparted, the force will
cause the distal end of the stretch-valve tube 3830 to slide
proximally and translate and open the drainage ports 3860, 3862 at
a deflation point, e.g., with a pulling force in a range of 1 to 15
pounds. In another exemplary embodiment, the range of force
required to meet the deflation point is between 1 and 5 pounds, in
particular, between 1.5 and 2 pounds.
[0273] When the deflation point of the stretch-valve tube 3830
occurs, the interior of the balloon 3842 becomes fluidically
connected directly into the drainage lumen 4212, 4312 (which is
open to the interior of the bladder 2020 and to the
non-illustrated, proximal drain bag) and, due to the fact that the
bladder is relatively unpressurized as compared to the balloon
3842, all internal pressure is released from the balloon 3842 to
eject the inflating fluid 3802 directly into the drainage lumen
4212, 4312, thereby causing the balloon 3842 to deflate
rapidly.
[0274] There exists the possibility that the distal end of
stretch-valve tube 3830 might not slide or will slide with friction
when the proximal end of the catheter 4200, 4300 is pulled to a
force that is enough to reach the desired deflation point (and no
greater than just before injury would occur). To prevent such a
situation from occurring, it is desirable to enhance the
stretchability of the inner lumen wall 4210 distal of the anchor
3832 and, in particular, the extent E between the drainage ports
3860, 3862 and the anchor 3832. Because the material of the
catheters described herein is naturally stretchable, there are
various ways to make the extent E stretch more than other portions
of the catheter, in particular, the portion proximal of the anchor
3832. One way to increase the stretchability is to score the
outside or inside of the material comprising the extent E with
small cuts, notches, scratches, or other intentionally formed
defects. Another way to make the extent E more stretchable than at
least the portion proximal of the anchor 3832 is to grind down the
exterior or interior of the extent E. A further way to make the
extent E more stretchable is to chemically treat the material
comprising the extent E. Yet another way to make the extent E more
stretchable is to treat the material comprising the extent E with a
local change in temperature, such as heating the extent E.
[0275] An altogether different way is to use different materials in
the catheter 4200, 4300. In one exemplary embodiment, at least a
portion of the extent E is replaced with another elastomeric
material different from the remainder of the catheter, the other
elastomeric material being more elastic than at least the portion
of the catheter proximal of the anchor 3832. In another exemplary
embodiment, the portion proximal of the anchor 3832 is made of an
elastomeric material that is less elastic than the extent E.
[0276] FIG. 43 shows the stretch-valve tube 4330 significantly
longer than the other stretch-valve tubes and attached by the
anchor 4332 to the inner lumen wall 4310 even further proximally
than the other stretch-valve tubes. By making the stretch-valve
tube 4330 longer, the extent E can be increased, thereby making
stretch of the portion just distal of the anchor 3832 easier and
insuring activation of the stretch valve. Any of the exemplary
embodiments of the stretch-valve tube can have a different length
than illustrated and/or described. Combining this increase or
decrease in length of the stretch-valve tube with a decrease in the
outer diameter of the stretch-valve tube can allow for tailoring
the stretch-valve tube to various stretch release forces as
described below with regard to FIG. 49.
[0277] Even though the exemplary embodiments 4200, 4300 are shown
herein with reference to FIG. 38, they are not limited thereto and
can be applied to each of the other exemplary embodiments described
herein as well. Further, the stretch enhancement feature can be
added to the outer wall instead of or in addition to the inner
lumen wall. If the stretch enhancement 4270, 4370 is included in
the production of any of the herein-mentioned catheters, then
another manufacturing step will be needed. As such, a
stretch-enhancement creation step will be added, for example, in
the flow chart of FIG. 39 anywhere after step 3910, in the flow
chart of FIG. 40 anywhere after step 4010, and in the flow chart of
FIG. 41 anywhere after step 4110.
[0278] Alternative exemplary embodiments combine various features
of the embodiments described herein. For example, FIGS. 44 to 47
illustrate other exemplary embodiments of the stretch-valve tubes
mentioned above. Where some features are mentioned already, similar
reference numerals are used and the descriptions thereof are not
repeated.
[0279] With regard to FIGS. 44 and 45, in contrast to a solid tube,
the stretch-valve tube 4430 of the inventive catheter 4500 has a
proximal tubular section 4432, a distal tubular section 4434, and
an intermediate connector 4436. As before, FIG. 45 illustrates a
balloon portion of the inventive catheter 4500 with a balloon 3842
in a partially inflated state. An annular inner lumen wall 3810
defines therein a drainage lumen 3812. At one or more
circumferential longitudinal extents about the inner lumen wall
3810, an inflation lumen wall 3820 defines an inflation lumen 3822
and a balloon inflation port 3824 fluidically connected to the
inflation lumen 3822; in the inventive catheter 4500, there can be
more than one inflation lumen 3822 and corresponding inflation port
3824 even though only one is shown herein. A lumen plug 3836
fluidically closes the inflation lumen 3822 distal of the inflation
port 3824 so that all inflation fluid 3802 is directed into the
balloon 3842. The lumen plug 3736 can plug any point or extent from
the inflation port 3724 distally. An outer wall 3840 covers all of
the interior walls 3810 and 3820 in a fluid-tight manner and forms
the exterior of the balloon 3842 but does not cover the distal end
of the drainage lumen 3812. The outer wall 3840 is formed in any
way described herein and is not discussed in further detail
here.
[0280] In this exemplary embodiment, the stretch-valve tube 4430 is
disposed in the drainage lumen 3812 to not hinder drainage of the
fluid to be drained (e.g., urine). While the diameter of the
stretch-valve tube 4430 can be any size that accommodates
substantially unhindered fluid flow through the drainage lumen
3812, one exemplary inner diameter of the stretch-valve tube 4430
is substantially equal to the diameter of the drainage lumen 3812
and the outer diameter of the stretch-valve tube 4430 is just
slightly larger than the diameter of the drainage lumen 3812 (e.g.,
the wall thickness of the tube can be between 0.07 mm and 0.7 mm).
The proximal tubular section 4432 of the stretch-valve tube 4430 in
this exemplary embodiment is proximal of a proximal end of the
deflation port 3860. The distal tubular section 4434 of the
stretch-valve tube 4430 is not distal of the distal end of the
balloon 3842 so that the balloon 3842 can be deflated; the distal
end can be anywhere between the two ends of the balloon 3842 but is
shown in an intermediate position in FIG. 45. The distal tubular
section 4434 of the stretch-valve tube 4430 covers the deflation
port 3860 longitudinally in the steady-state or unactuated state of
the valve. The overlap distance S distal of the deflation port 3860
is dependent upon the amount of stretch required to actuate the
stretch-valve of the inventive catheter 4500 as described
below.
[0281] To secure the stretch-valve tube 4430 in the catheter 4500,
a proximal anchor 3832 is disposed in the drainage lumen 3810 away
from the deflation ports 3860, 3862, here proximally. The proximal
anchor 3832 can be any size or shape that accommodates
substantially unhindered fluid flow through the drainage lumen
3812, one exemplary inner diameter of the hollow anchor 3832 being
a tube or ring substantially equal to the diameter of the drainage
lumen 3812 with an outer diameter just slightly larger than the
diameter of the drainage lumen 3812 (e.g., the thickness of the
tube can be between 0.07 mm and 0.7 mm). The proximal anchor 3832
can be a barb or other mechanical fixation device as well, whether
integral or connected to the stretch-valve tube 4430. The
longitudinal length of this hollow anchor 3832 can be as long as
desired but just enough to longitudinally fixedly secure the
stretch-valve tube 4430 within the drainage lumen 3812 when
installed in place. The anchor 3832 in this exemplary embodiment is
at the proximal end of the balloon 3842 but can be further inside
the balloon 3842 (distal) or entirely proximal of the balloon 3842
as shown. In an exemplary embodiment, the anchor 3832 has a stepped
distal orifice that permits the proximal end of the stretch-valve
tube 4430 to be, for example, press-fit therein for permanent
connection. In another exemplary embodiment, the anchor 3832 is an
adhesive or glue that fixes the proximal end of the stretch-valve
tube 4430 longitudinally in place within the drainage lumen 3812.
The adhesive can be the same material as any or all of the walls
3810, 3820, 3840 or it can be a different material. In an exemplary
non-illustrated embodiment where a fixation port or set of fixation
ports are formed through the inner wall 3810 proximal of the
proximal-most end of the balloon 3842 and about the proximal end of
the stretch-valve tube 4430, if the outer wall 3840 is formed by a
dipping of the interior parts into a liquid bath of the same
material as, for example, a dual lumen extrusion including the
inner wall 3810 and the inflation lumen wall 3820, then, when set,
the outer wall 3840 will be integral to both the inner wall 3810
and the inflation lumen wall 3820 and will be fixedly connected to
the stretch-valve tube 3820 through the fixation port(s). (Further
exemplary embodiments for securing the stretch-valve tube 4430 in
the catheter 4500 are described below with regard to FIGS. 48 and
49.)
[0282] In such a configuration, therefore, any proximal movement of
the catheter 4500 at or proximal to the deflation ports 3860, 3862
will also move the stretch-valve tube 4430 proximally; in other
words, the distal end of the stretch-valve tube 4430 can slide
within the drainage lumen 3812 in a proximal direction. When the
proximal end of the catheter 4500 is pulled to a force that is no
greater than just before injury would occur to the bladder-urethral
junction or the urethra if the catheter 4500 was still inflated
when the force was imparted, the force will cause the stretch-valve
tube 4430 to slide proximally to place the distal end of the
stretch-valve tube 4430 just proximal of the deflation ports 3860,
3862, e.g., with a pulling force in a range of 1 to 15 pounds. In
another exemplary embodiment, the range of force required to meet
the deflation point is between 1 and 5 pounds, in particular,
between 1.5 and 2 pounds.
[0283] When the deflation point of the stretch-valve tube 4430
occurs, the interior of the balloon 3842 becomes fluidically
connected directly into the drainage lumen 3812 (which is open to
the interior of the bladder 2020 and to the non-illustrated,
proximal drain bag) and, due to the fact that the bladder is
relatively unpressurized as compared to the balloon 3842, all
internal pressure is released from the balloon 3842 to eject the
inflating fluid 3802 directly into the drainage lumen 3812, thereby
causing the balloon 3842 to deflate rapidly. Because there is no
intermediate structure between the balloon inflating fluid 3802 and
the drainage lumen 3812, the rate at which the balloon 3842
deflates is fast. One way to speed up deflation can be to shape the
deflation ports 3860, 3862 in the form of a funnel outwardly
expanding in a direction from the outer wall 3840 towards the
interior of the catheter 3800. Another way to speed up deflation
can be to have two or more deflation ports 3860 about the
circumference of the inner lumen wall 3810 and/or to enlarge the
cross-sectional area of the deflation ports 3860, 3862.
[0284] The intermediate portion 4436 is not solid and is, instead,
either a small tubular arc section (shown) or even multiple arc
sections (not illustrated) or can be merely a line connecting the
two tubular portions 4432, 4434 together (not illustrated). As
such, the stretch-valve tube 4430 defines an intermediate flex gap.
In such a configuration, if made from the same material as the
other stretch-valve tubes described herein, the stretch-valve tube
4430 has increased flexibility due to the decrease in material
used. If made of a material that has less flexibility, then the
shortened proximal and distal portions 4432, 4434 combined with the
narrow intermediate portion 4436 allows the stretch-valve tube 4430
to be sufficiently flexible to not hinder insertion of the catheter
4500. Further, insertion of the stretch-valve tube 4430 into the
drainage lumen is similar.
[0285] With regard to FIGS. 46 and 47, also in contrast to a solid
tube, the stretch-valve assembly 4730 of the inventive catheter
4700 has a proximal coil section 4632, a distal plug 4634, and a
distal coil section 4436. As before, FIG. 47 illustrates a balloon
portion of the inventive catheter 4700 with a balloon 3842 in a
partially inflated state. An annular inner lumen wall 3810 defines
therein a drainage lumen 3812. At one or more circumferential
longitudinal extents about the inner lumen wall 3810, an inflation
lumen wall 3820 defines an inflation lumen 3822 and a balloon
inflation port 3824 fluidically connected to the inflation lumen
3822; in the inventive catheter 4700, there can be more than one
inflation lumen 3822 and corresponding inflation port 3824 even
though only one is shown herein. A lumen plug 3836 fluidically
closes the inflation lumen 3822 distal of the inflation port 3824
so that all inflation fluid 3802 is directed into the balloon 3842.
The lumen plug 3736 can plug any point or extent from the inflation
port 3724 distally. An outer wall 3840 covers all of the interior
walls 3810 and 3820 in a fluid-tight manner and forms the exterior
of the balloon 3842 but does not cover the distal end of the
drainage lumen 3812. The outer wall 3840 is formed in any way
described herein and is not discussed in further detail here.
[0286] In this exemplary embodiment, the stretch-valve assembly
4630 is disposed in the drainage lumen 3812 to not hinder drainage
of the fluid to be drained (e.g., urine). The proximal coil section
4632 has a larger diameter than the intermediate coil section 4636
because the proximal coil section 4632 acts as the device to secure
the stretch-valve assembly 4630 inside the drainage lumen 3812 and
the intermediate coil section 4636 acts as the measures by which
the distal plug 4634 is moved out and away from the deflation port
3860, 3862. The intermediate coil section 4636 can have a pitch
with looser coils to permit bending of the catheter body without
kinking. While the diameter of the proximal coil section 4632 can
be any size that accommodates substantially unhindered fluid flow
through the drainage lumen 3812, one exemplary outer diameter of
the rest- or steady-state of the proximal coil portion 4632 is just
slightly larger than the diameter of the drainage lumen 3812 (e.g.,
the wall thickness of the tube can be between 0.07 mm and 0.7 mm).
In comparison, one exemplary outer diameter of the rest- or
steady-state of the intermediate coil section 4636 is just slightly
smaller than the diameter of the drainage lumen 3812. In this
manner, proximal movement of the secured proximal coil section 4632
pulls upon the intermediate coil section 4636 to cause the distal
plug 4634 to slide out and proximally away from the deflation port
3860, 3862. One exemplary configuration of the distal plug 4634 is
a heat shrunk polyolefin attached to the coil with
cyanoacrylate.
[0287] The proximal coil section 4632 of the stretch-valve assembly
4630 in this exemplary embodiment is proximal of a proximal end of
the deflation port 3860, 3862. The distal plug 4634 of the
stretch-valve assembly 4630 is not distal of the distal end of the
balloon 3842 so that the balloon 3842 can be deflated; the distal
plug 4634 can be anywhere between the two ends of the balloon 3842
but is shown in an intermediate position in FIG. 47. The distal
plug 4634 of the stretch-valve assembly 4630 covers the deflation
ports 3860, 3862 longitudinally in the steady-state or unactuated
state of the valve. An overlap distance distal of the deflation
ports 3860, 3862 is dependent upon the amount of stretch required
to actuate the stretch-valve of the inventive catheter 4700 as
described below.
[0288] To secure the stretch-valve assembly 4630 in the catheter
4700, no proximal anchor is needed in addition to the stretch-valve
assembly 4630. Here, the proximal anchor is the proximal coil
section 4632, which, when allowed to expand to its native diameter,
self-secures in the drainage lumen 3812 and accommodates
substantially unhindered fluid flow through the drainage lumen
3812. The longitudinal length of the proximal coil section 4632 can
be as long as desired but just enough to longitudinally fixedly
secure the stretch-valve assembly 4630 within the drainage lumen
3812 when installed in place. The anchor 4632 in this exemplary
embodiment is proximal of the proximal end of the balloon 3842 but
can be further inside the balloon 3842 (distal) or even further
proximal of the balloon 3842 than shown. In another exemplary
embodiment, an adhesive or glue can fix the proximal coil section
4632 of the stretch-valve assembly 4630 longitudinally in place
within the drainage lumen 3812. The adhesive can be the same
material as any or all of the walls 3810, 3820, 3840 or it can be a
different material. In an exemplary non-illustrated embodiment
where a fixation port or set of fixation ports are formed through
the inner wall 3810 proximal of the proximal-most end of the
balloon 3842 and about the proximal coil section 4632 of the
stretch-valve assembly 4630, if the outer wall 3840 is formed by a
dipping of the interior parts into a liquid bath of the same
material as, for example, a dual lumen extrusion including the
inner wall 3810 and the inflation lumen wall 3820, then, when set,
the outer wall 3840 will be integral to both the inner wall 3810
and the inflation lumen wall 3820 and will be fixedly connected to
the proximal coil section 4632 through the fixation port(s).
[0289] In such a configuration, therefore, any proximal movement of
the catheter 4700 at or proximal to the drainage ports 3860, 3862
will also move the stretch-valve assembly 4630 proximally; in other
words, the distal plug 4634 of the stretch-valve assembly 4630 can
slide within the drainage lumen 3812 in a proximal direction. When
the proximal end of the catheter 4700 is pulled to a force that is
no greater than just before injury would occur to the
bladder-urethral junction or the urethra if the catheter 4700 was
still inflated when the force was imparted, the force will cause
the distal plug 4634 to slide proximally to open the drainage ports
3860, 3862, e.g., with a pulling force in a range of 1 to 15
pounds. In another exemplary embodiment, the range of force
required to meet the deflation point is between 1 and 5 pounds, in
particular, between 1.5 and 2 pounds.
[0290] One exemplary method for installing the stretch-valve
assembly 4630 in the drainage lumen 3812 is to turn down the coil
of the proximal coil section 4632 temporarily on a mandrel that has
a diameter equal to or smaller than the inner diameter of the
intermediate coil section 4636 and hold it in place. Then, the
contracted proximal coil section 4632 is inserted into the drainage
lumen 3812 to the implantation or securing point. The, contracted
proximal coil section 4632 is allowed to expand, thereby securing
proximal portion of the stretch-valve assembly 4630 in the drainage
lumen 3812 with the intermediate coil section 4636 and distal plug
4634 movably disposed therein.
[0291] The proximal and intermediate coil sections 4632, 4636 can
be made of a single coil that is wound with two different diameters
and/or two different pitches.
[0292] As set forth above, many of the exemplary catheters
described herein can connect the stretch-valve tube merely by the
shape of the tube itself. This connection is described with
reference to FIG. 48, which illustrates a configuration of a
catheter 4800 having features that applicable to each of the
exemplary catheters described herein. Thus, the "48" prefix will be
used for illustration purposes. In each of the catheters, an
annular inner lumen wall 4810 defines therein a drainage lumen 4812
and an inflation lumen wall 4820 defines an inflation lumen 4822
and a non-illustrated balloon inflation port fluidically connected
to the inflation lumen 4822. An outer wall 4840 covers an of the
interior walls 4810 and 4820 in a fluid-tight manner and forms the
exterior of the balloon 4842. A hollow, stretch-valve tube 4830 is
disposed in the drainage lumen 4812 to not hinder drainage of the
fluid to be drained (e.g., urine). While the diameter of the
stretch-valve tube 4830 can be any size that accommodates
substantially unhindered fluid flow through the drainage lumen
4812, the exemplary outer diameters of the stretch-valve tube 4830
allow the distal end of the stretch-valve tube 4830 to slide within
the drainage lumen 4812 when the valve is activated. One exemplary
size of the stretch-valve tube 4830 has one or more of the proximal
and distal ends thereof larger in outer diameter than an
intermediate portion of the stretch-valve tube 4830. Thus, if one
end is larger, the stretch-valve tube 2830 has a "club" shape and,
if both ends are larger, the stretch-valve tube 4830 has a
"dumbbell" shape. An exemplary configuration of a dumbbell shaped
stretch-valve tube is described hereinbelow.
[0293] In the various embodiments of catheters described herein,
one end of the stretch-valve tube is indicated as being "fixed" in
the respective catheter, while the opposite end is slidably
disposed therein. Some exemplary embodiments described for fixing
this end include adhesives (such as cyanoacrylate) and structures,
and some describe the fixation as being fixed solely from its shape
alone. As used herein, therefore, the measures for "fixation" do
not need to be a separate material or a separate device.
Accordingly, some exemplary embodiments can provide fixation of the
stretch-valve tube simply by inserting the stretch-valve tube
within the respective lumen. More specifically, one consequence of
stretching the flexible catheter (for example, when a urinary
catheter is prematurely pulled out) is that the stretched portion
collapses radially inwards towards the longitudinal axis as the
catheter body lengthens. There are two common examples of
explaining this behavior: the Poisson Effect and the Chinese finger
trap.
[0294] The Poisson effect is a negative ratio of transverse to
axial strain. When a sample object is stretched (or squeezed), to
an extension (or contraction) in the direction of the applied load,
it corresponds to a contraction (or extension) in a direction
perpendicular to the applied load. More specific to the invention
herein, when the catheter is pulled relative to its ends, the
catheter contracts in diameter and circumference. Therefore if a
more rigid tube (the stretch valve) is placed in the lumen of a
less rigid tube (the catheter), the diameter of the catheter
decreases as it is extended axially and hugs the stretch valve. If
the distal balloon on the catheter is held in place by the
bladder-urethral junction and the proximal end of the catheter is
pulled axially, as the catheter diameter contracts, it hugs the
stretch valve and pulls the stretch valve proximally to the extent
that it releases fluid from the balloon into at least one of the
lumens in the catheter. This hugging is more pronounced on the
proximal end (the right end in FIG. 48 than on the distal end). As
such, the proximal end of the stretch-valve tube is squeezed while
the distal end of the stretch-valve tube moves proximally to open
the safety valve.
[0295] Another way to explain this effect is with the Chinese
finger trap, also known as a Chinese finger puzzle or Chinese
handcuffs (a gag toy used to play a practical joke). The finger
trap is a simple puzzle that snares the victim's fingers (often the
index fingers) in both ends of a small, woven bamboo cylinder. The
initial reaction of the victim is to pull the fingers outward
(i.e., stretching the tube), but this only tightens the trap. The
way to escape the trap is to push the ends toward the middle, which
enlarges the circumference of the two end openings and frees the
fingers. The tightening is simply a normal behavior of a
cylindrical, helically wound braid, usually the common biaxial
braid. Pulling the entire braid from its ends lengthens and narrows
it. The length is gained by reducing the angle between the warp and
weft threads at their crossing points, but this reduces the radial
distance between opposing sides and hence the overall
circumference.
[0296] The stretch-valve described herein takes advantage of the
Poisson and Chinese Puzzle Effects by extending the stretch-valve
tube 4830 sufficiently proximal so that the proximal end resides
within the area of stretching. This distance need not be far
towards the proximal end of the catheter and can even reside in the
proximal end of the balloon 4842. However, it has been found that a
short distance, such as a few millimeters to a few centimeters is
all that is needed to position the proximal end in the area of
stretching. As such, when the balloon 4842 is held stationary
(e.g., in the bladder) and the proximal end of the catheter is
pulled (e.g., by a patient), the reduction in circumference of the
drainage lumen 4812 automatically increases the inward grasping
force on the proximal end of the stretch-valve tube 4830 but does
not place the same inward force against the distal end of the
stretch-valve tube 4830 covering the drainage port (not illustrated
in FIG. 48). This effect is illustrated in the enlarged FIG. 48
(which is not drawn to scale) where the distal portion of the
stretch-valve tube 4830 shown (to the left) does not touch the
interior wall of the drainage lumen 4812 but the proximal end of
the stretch-valve tube 4830 (to the right) is squeezed by the
interior wall of the drainage lumen 4812. Simply put, as the
proximal end of the catheter 4800 is pulled away from the balloon
4842, the center portion 4850 of the catheter 4800 being stretched
decreases in circumference C' and grips the proximal end of the
stretch-valve tube 4830 while the unstretched or less-stretched
portion 4860 substantially retains its circumference C, thereby
allowing the distal end of the stretch-valve tube 4830 to slide and
actuate the stretch valve of the present invention.
[0297] In this embodiment, therefore, all of the fixation
through-holes 2150, 2450, 2750, 3732, 3832 describe above become
unnecessary and lead to a very simple configuration for
manufacturing. Not only the shape itself can provide the fixation
as described, properties of the stretch-valve tube and the material
comprising the lumen in which the stretch-valve tube resides can
provide the fixation as well. For example, if the material of the
stretch-valve tube 4830 is selected such that it slightly grips the
interior of the drainage lumen 4812 (or vice versa), then the
gripping of the proximal end of the stretch-valve tube 4830 can be
increased.
[0298] In some of the various embodiments of catheters described
herein, the stretch-valve tubes have been shown as smooth
cylinders. Alternative exemplary embodiments of these stretch-valve
tubes do not require a constant outer diameter. The ability to
tailor release of the stretch-valve can be enhanced when the
stretch-valve tube 4900 has either or both of the proximal 4910 and
distal 4920 ends of the stretch-valve tube 4900 larger in outer
diameter than an intermediate portion 4930 of the stretch-valve
tube 4900. In such a configuration, if one end is larger, the
stretch-valve tube has a "club" shape (not illustrated) and, if
both ends are larger (as shown in FIG. 49), the stretch-valve tube
4900 has a "dumbbell" shape.
[0299] The proximal 4910 and distal 4920 ends of the stretch-valve
tube 4900 can be equal in outer diameter 4912, 4922 or they can
have different outer diameters. In an exemplary embodiment, the
outer surface of the distal end 4920 is smooth to seal against the
deflation port(s). The outer surface of the proximal end 4910 can
be smooth or rough or have fastening devices (such as barbs,
extensions, adhesives). In an exemplary embodiment the outer
diameter 4912 of the proximal end 4910 is slightly larger than the
outer diameter 4922 of the distal end 4920. The overall length of
the stretch-valve tube 4900 is between 1.5'' and 3'' or longer.
[0300] The following is an exemplary embodiment of a stretch valve
tube 4900 where the inner diameter of the lumen in which the
stretch-valve tube 4900 is to be placed (e.g., drain lumen of a
Foley catheter) is 0.1'' and the balloon of the catheter has a
length of 1.0'' with the balloon inflation hole and the drainage
port located in the center of the balloon. For such a
configuration, the approximate dimensions for the stretch valve
made from a polyurethane tube of Shore 95A with a wall thickness of
between approximately 0.004'' and approximately 0.012'', in
particular, between approximately 0.006'' and approximately
0.009'', are as set forth in the following text.
[0301] The length of the proximal end 4912 is between approximately
0.1'' and approximately 0.5'', in particular, approximately 0.25''.
The outer diameter 4914 of the proximal end 4910 is between
approximately 0.1'' to 0.15'', in particular, approximately
0.110''. The length of the distal end 4922 is between approximately
0.1'' and approximately 0.5'', in particular, approximately 0.25''.
The outer diameter 4924 of the distal end 4920 is between
approximately 0.1'' to 0.15'', in particular, approximately
0.108''. The length 4932 of the intermediate portion 4930 is
between approximately 0.5'' and approximately 3'' or longer, in
particular, approximately 2''. The outer diameter 4934 of the
intermediate portion 4930 is between approximately 0.1'' to 0.09'',
in particular, approximately 0.095''.
[0302] It is noted that the length 4914 of the proximal end does
not need to be the same as the length 4924 of the distal end and,
in particular, it can be longer. Further, where the diameter
measurement is normalized to 0.1'' as above, the outer diameter
4914 of the proximal end 4910 is 10% larger and the outer diameter
4924 of the distal end 4920 is 8% larger. The inner diameter of the
proximal 4920, intermediate 4930, and proximal 4910 portions can be
the same or different (as shown. The wall thickness, too, can vary
throughout if desired. For example, where the tube is an extrusion
and the intermediate portion 4930 is made smaller by stretching,
the wall will be reduced where it is stretched.
[0303] The drainage port of the balloon is located somewhere along
the length 4922 of the distal end 4920, anywhere from the center of
the length 4922 to 25% on either side thereof and, in particular,
within the proximal 75% of the length 4922. If desired, the area
opposing the drainage portion on the length 4922 can have raised
boss to have a form-fit into the port.
[0304] If the stretch-valve tube is made by extrusion, it can be
modified on a mold after it is extruded.
[0305] Each of the stretch-valve embodiments of FIGS. 21 to 38 and
42 to 49 also affords another significant benefit. The presence of
the stretch-valve provides a way to self-regulate the balloon so
that it is able to deflate automatically when over-inflated, a
characteristic that is not present in the prior art. More
specifically, when the balloon is overinflated, the stretch valve
actuates to release the excessive pressure into the drain lumen.
When the balloon is inflated to its intended size with the
pre-defined amount of inflation fluid, the balloon expands without
stretching any portion of the multi-lumen interior or the catheter
material proximal of or distal to the balloon. However, when the
balloon is over-inflated, this excessive inflation forces the ends
of the balloon (i.e., the distal and proximal poles of the circular
balloon) attached to the catheter to move away from each other. As
this movement occurs, the stretch valve begins to actuate. If the
balloon is over-inflated sufficiently to actuate the stretch valve,
the resulting movement automatically deflates the balloon until the
proximal and distal ends of the balloon no longer stretch the
catheter portions surrounding the balloon. When the ends of the
balloon are no longer stretched, the stretch valve closes, thereby
stopping deflation mid-stream and retaining the balloon in its
intended inflation size.
[0306] In an exemplary embodiment of the safety urinary catheter,
the stretch valve has the stretched state when the length between
the proximal end of the catheter and the proximal balloon end is
elongated between approximately 5 percent and approximately 200
percent, in particular, between approximately 5 percent and
approximately 75 percent. Alternatively, or additionally, the
stretch valve has the stretched state when the length between the
ends of the balloon is elongated between approximately 5 percent
and approximately 200 percent, in particular, between approximately
5 percent and approximately 75 percent.
[0307] The existence of the stretch valve also provides a further
benefit--the ability to control and eliminate inflation when the
balloon is constricted. It is known that inflation of a balloon in
a lumen that is much smaller than the intended destination is a
common occurrence (e.g., when the balloon of a catheter is
attempted to be inflated within the confines of a urethra instead
of the bladder) and leads to serious and debilitating patient
injuries. Prior art catheters are unable to prevent inflation when
constricted in a small lumen. In contrast, the stretch valve
configurations described herein are able to prevent inflation when
constricted in a small lumen. As described above, in addition to
stretching in the radial direction, the balloon also stretches in
the longitudinal direction--the same direction as the actuation
axis of the stretch valve. When constricted in a lumen, the balloon
is not permitted to stretch radially but is permitted to stretch
longitudinally. This stretching causes the stretch valve to open
prior to causing significant damage to the lumen in which the
balloon is being inflated (e.g., the urethra), thereby directing
the inflation fluid into the drain lumen instead of the balloon. In
the particular embodiment of a urinary drainage catheter, the
stretch valve opens before injury is caused to the lumen of the
urethra.
[0308] In each of the embodiments where a stretch valve exists,
actuation of the stretch valve within the patient can be indicated
visually to a user or a health professional--a situation that is
not able to be provided by prior art balloon catheters. As
described above, a technician/physician/user inserting a balloon
catheter does not know where the balloon is placed within the body
after the balloon is inserted therein unless some type of costly
radiographic or sonographic equipment is used. With the inventive
safety catheters described herein, however, the inflation fluid has
the opportunity to exit the balloon and, when it does, it provides
a unique and automatic way of informing the user or health-care
professional that a dangerous condition has just been prevented and
additional attention is desirable. More specifically, if the
inflation fluid contains an inert colorant that is different from
any color of fluid that typically is drained by the balloon
catheter, the herein-described safety catheters will show, visually
and immediately, either that an attempt has been made to inflate
the balloon within a constricted lumen (such as the urethra) or
that the catheter has been stretched enough to cause the
stretch-valve of the inserted balloon to act and prevent possible
pull-out injury. Almost immediately after triggering, the colored
inflation fluid enters the fluid drainage bag. When anyone sees
this colored fluid, he/she knows that the balloon is not correctly
placed and corrective action needs to be taken immediately before
injury or further injury occurs.
[0309] In most of the embodiments described herein, reference is
made to a urinary drainage catheter. As set forth herein, this is
merely one good exemplary embodiment for describing the inventive
safety features outlined herein. Specifically, the inventive
features are not limited to a urinary drainage catheter; they can
be applied to various and numerous catheter devices that probe
various other areas of the anatomy and are used in other clinical
situations.
[0310] In a first alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
coronary sinus catheter insertion. A coronary sinus catheter is a
flexible device with a balloon at its end to be placed in the
coronary sinus vein in the back of heart. It is used to deliver
retrograde cardioplegia solution to arrest the heart for open heart
surgery. In the prior art, if the balloon is overly distended, the
vessel (CS) may rupture or bleed excessively, causing great harm to
the patient or death. The stretch valve can be included in the
coronary sinus catheter to limit the amount of inflation of that
balloon, thereby preventing distension of the coronary sinus.
[0311] In a second alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with airway
breathing tubes (such as endotracheal tubes and tracheostomy
tubes). These devices are used commonly in medical care to provide
assistance with breathing. After the trachea has been intubated, a
balloon cuff of these devices is typically inflated just above the
far end of the tube to help secure it in place, to prevent leakage
of respiratory gases, and to protect the tracheobronchial tree from
receiving undesirable material such as stomach acid. The tube is
then secured to the face or neck and connected to a T-piece,
anesthesia breathing circuit, bag valve mask device, or a
mechanical ventilator. Over-distention of the balloon cuff can
cause trauma and damage to the lining of the airway over time. This
is so critical that medical personnel attempt to check the pressure
of the balloon cuff at the time of first inflation and often
thereafter. But gases may diffuse into or out from the balloons
over time or too much air can be placed in the balloon
inadvertently. The stretch valve can be included in these airway
breathing tubes to limit the amount of inflation of that balloon,
thereby preventing distension of the trachea.
[0312] In a third alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
thrombus removal devices, for example, Fogarty-type, atherectomy
balloon catheters. These catheters are used to pull thrombi out of
arteries. Accordingly, if the balloon of such catheters is
over-inflated or over-pressurized (i.e., when the balloon is
inflated in a compressed state such as in a lumen that is smaller
than the balloon diameter), it can cause damage to the arterial
wall, resulting in stenosis. The stretch valve can be included in
these thrombus removal devices to limit the amount of inflation of
that balloon, thereby preventing damage to arterial walls. Other
Fogarty-type balloons are used to dilate strictures such as
arterial venous fistula used for dialysis. These fistulas commonly
stricture. In use, the Fogarty-type balloon is advanced proximal to
the stricture and the balloon is inflated. The inflated balloon
then is rapidly withdrawn across the stricture, which then opens
the stricture by fracturing the fibrous bands. However it is not
uncommon for the balloon to rupture and leave a foreign body in the
lumen, which then would require an emergency operation. A balloon
that self-deflates when experiencing such high pressures such as
one including the stretch valve would prevent this from happening.
Balloons are used to dilate strictures in almost any vessel in the
body. Examples include, but are not limited to, strictures in the
common bile duct, pancreatic duct, intestinal strictures often at
anastomotic sites, lacrimal ducts, and parotid ducts. These vessels
are often very delicate and can be damaged with over inflation.
Strictures also occur in the urethtra, in the ureter, in the
esophagus, and in the gastrointestinal tract. In each case,
over-inflation of the balloon can cause a burst that may injury the
structure in which it is being used. Combining the stretch valve
described herein with such balloons would prevent this complication
from happening.
[0313] In a fourth alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with balloon
isolation catheters, which are used to block the flow of blood, for
example, while drugs are injected on either side of the blockage.
Over-distension of the balloon can cause damage to the vessel in
which the isolation catheter is inflated. The stretch valve can be
included in these balloon isolation catheters to limit the amount
of inflation of that balloon, thereby preventing damage to lumen
walls.
[0314] In a fifth alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
angioplasty balloon catheters, in particular, those comprised of
flexible balloons including Nylon 12. Over-inflation of the balloon
in such catheters can lead to rupture of the artery, which can be
catastrophic to the patient. The stretch valve can be included in
these angioplasty balloon catheters to limit the amount of
inflation of that balloon, thereby preventing damage to lumen
walls.
[0315] In a sixth alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
valvuloplasty catheters. Such catheters are used to break calcium
deposits in heart valves. Over-distention can damage cells in the
annulus of the valve, which can lead to inflammation and scar
tissue formation. The stretch valve can be included in these
valvuloplasty catheters to limit the amount of inflation of that
balloon, thereby preventing damage to the annulus.
[0316] In a seventh alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
vertebroplasty balloons. If balloons for vertebroplasty are
over-distended, they can cause rupturing of the vertebra. A release
mechanism will render this procedure safer. The stretch valve is
such a release mechanism for inclusion in a vertebroplasty
device.
[0317] In an eighth alternative exemplary embodiment, the
self-regulating and self-deflating balloon can be used with
tamponade procedures. One example is during bronchoscopy when a
biopsy is taken. After such a procedure, bleeding may occur. A
balloon is passed over the bleed and inflated to compress the
bleeding vessel. However, over-inflation in this delicate organ can
easily cause ischemic damage. The stretch valve disclosed herein
can be used with the tamponade balloon to prevent any injury from
happening.
[0318] The various catheters 200, 300, 1000, 1600, 2100, 2400,
2700, 3300, 3400, 3500, 3600, 3700, 3800, 4200, 4300, 4500, 4700,
4800, 4900 described herein mention the catheter stretching from
its proximal end when pulled. This movement can be described
equally and correspondingly as a longitudinal movement of one of
the ends of the balloon relative to the other of the ends of the
balloon or, likewise, can be described as a longitudinal movement
of one of the ends of the balloon away from the other of the ends
of the balloon.
[0319] The catheters 200, 300, 1000, 1600, 2100, 2400, 2700, 3300,
3400, 3500, 3600, 3700, 3800, 4200, 4300, 4500, 4700, 4800, 4900
according to the invention can be used in vascular applications. It
is known that every vessel has a tearing pressure. Balloons are
used in coronary arteries, for example. If a coronary artery
balloon were to burst, there would be less damage if the burst was
controlled according to the invention. The same is true for a renal
or iliac blood vessel. In such situations, the breakaway catheter
improves upon existing catheters by making them safer. From the
urinary standpoint, the breakaway balloon will not only prevent
injury, but will also be a signal to the technician that he/she
needs to obtain the assistance of a physician or urologist with
respect to inserting the catheter.
* * * * *