U.S. patent application number 10/942531 was filed with the patent office on 2005-02-17 for fecal incontinence management device.
This patent application is currently assigned to X-L Synergy. Invention is credited to Nemir, David C., Rubio, Edward.
Application Number | 20050038380 10/942531 |
Document ID | / |
Family ID | 33567195 |
Filed Date | 2005-02-17 |
United States Patent
Application |
20050038380 |
Kind Code |
A1 |
Nemir, David C. ; et
al. |
February 17, 2005 |
Fecal incontinence management device
Abstract
An apparatus, and corresponding method, for management of fecal
incontinence comprising a catheter having at least two electrodes
and an inflatable balloon, a non-conductive sleeve surrounding the
electrodes, and an alarm box, wherein the catheter is insertable
into a rectal vault and is inflatable to serve as a block to
passage of stool and wherein moisture sensed by the electrodes
triggers the alarm box and thereby notifies a user that fecal
material has entered the rectal vault.
Inventors: |
Nemir, David C.; (El Pasco,
TX) ; Rubio, Edward; (El Paso, TX) |
Correspondence
Address: |
PEACOCK MYERS AND ADAMS P C
P O BOX 26927
ALBUQUERQUE
NM
871256927
|
Assignee: |
X-L Synergy
El Paso
TX
|
Family ID: |
33567195 |
Appl. No.: |
10/942531 |
Filed: |
September 15, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10942531 |
Sep 15, 2004 |
|
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10401479 |
Mar 28, 2003 |
|
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60435808 |
Dec 21, 2002 |
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Current U.S.
Class: |
604/66 |
Current CPC
Class: |
A61F 2/0013
20130101 |
Class at
Publication: |
604/066 |
International
Class: |
A61M 031/00 |
Claims
What is claimed is:
1. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end; said distal end having a tip; conductivity sensor
means on the exterior of said probe body near said distal end, said
sensor means being connectable to an electrical circuit to
establish an alert signal in the presence of fecal material, and
wherein said sensor means are axially spaced-apart conductive
means; and an inflatable cuff extending about said probe body at a
location on said body spaced from said sensor means, said cuff
having air release means allowing the inflatable cuff to deflate
over a period of time.
2. The device of claim 1 wherein said axially spaced-apart
conductive means comprise conductive point contacts.
3. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end wherein at least a portion of said probe body
defines venting means to allow venting of flatus; said distal end
having a tip; conductivity sensor means on the exterior of said
probe body near said distal end, said sensor means being
connectable to an electrical circuit to establish an alert signal
in the presence of fecal material, and wherein said conductive
means are conductive contacts and said sensor means are shielded by
a perforated sleeve; and an inflatable cuff extending about said
probe body at a location on said body spaced from said sensor
means, said cuff having air release means allowing the inflatable
cuff to deflate over a period of time.
4. A device for insertion into the human colon to monitor bowel
incontinence by detecting the presence of fecal matter, said device
comprising: a generally flexible tubular probe body defining a
lumen, said body having a proximal and distal end; conductivity
sensor means on the exterior of said probe body adjacent said
distal end, said sensor means being connectable to an electrical
circuit which will transmit an alert signal in the presence of
fecal matter; a removable sleeve extending about said sensor means,
said sleeve partially shielding said sensor means to prevent false
alarms; and an inflatable cuff extending about said probe body
connectable to an air supply.
5. The device of claim 4 wherein said sleeve has a generally
cylindrical body with a bore selected to define an annular space
between said cylindrical body and said sensor and wherein said
cylindrical body defines an aperture to allow fecal matter to pass
into said annular space.
6. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end; said distal end having a tip; conductivity sensor
means on the exterior of said body near said distal end, said
sensor means being connectable to an electrical circuit to
establish an alert signal in the presence of fecal material; and an
inflatable cuff extending about said probe body at a location on
said body spaced from said sensor means, said cuff having air
release means allowing the inflatable cuff to deflate over a period
of time and being a material permeable to gas.
7. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end; said distal end having a tip; conductivity sensor
means on the exterior of said body near said distal end, said
sensor means being connectable to an electrical circuit to
establish an alert signal in the presence of fecal material, and
wherein said conductivity sensors are axially spaced-apart
conductive means; and an inflatable cuff extending about said probe
body at a location on said body spaced from said sensor means, said
cuff having air release means allowing the inflatable cuff to
deflate over a period of time.
8. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end; said distal end having a tip; conductivity sensor
means on the exterior of said body near said distal end, said
sensor means being connectable to an electrical circuit to
establish an alert signal in the presence of fecal material, and
wherein said sensors are conductive point contacts; and an
inflatable cuff extending about said probe body at a location on
said body spaced from said sensor means, said cuff having air
release means allowing the inflatable cuff to deflate over a period
of time.
9. A device for insertion into the human rectum to monitor bowel
incontinence by detecting the presence of fecal material, said
device comprising: a probe body defining a lumen having a distal
and proximal end; said distal end having a tip; conductivity sensor
means on the exterior of said body near said distal end, said
sensor means being connectable to an electrical circuit to
establish an alert signal in the presence of fecal material and
shielded by a perforated sleeve; and an inflatable cuff extending
about said probe body at a location on said body spaced from said
sensor means, said cuff having air release means allowing the
inflatable cuff to deflate over a period of time.
10. A method of detecting and controlling bowel incontinence, the
method comprising the steps of: providing a rectal probe having a
distal and proximal end and defining a lumen; providing
conductivity sensors on said probe which are connectable to an
alert system, said sensors located so an electrical circuit is
completed in the presence of fecal matter which will activate an
alarm; providing an inflatable cuff of a material having
predetermined permeability on said probe having air release means;
inserting the probe and cuff into the patient's colon; and
cyclically inflating and deflating the cuff to retain the probe in
position and to block passage of fecal matter and to stimulate the
rectal area.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
patent application Ser. No. 10/401,479 entitled "Fecal Incontinence
Management Device", to Nemir et al., filed on Mar. 28, 2003 which
claimed the benefit of the filing of U.S. Provisional Patent
Application Ser. No. 60/435,808 entitled "Fecal Incontinence
Management Device", to Nemir et al., filed on Dec. 21, 2002, and
the specifications and claims of both applications are incorporated
herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT
DISC
[0003] Not Applicable.
COPYRIGHTED MATERIAL
[0004] Not Applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention (Technical Field):
[0006] This invention relates to an apparatus and method for the
treatment of fecal incontinence wherein a fecal dam and fecal
matter sensor are retained within the rectal vault to both prevent
the passage of stool and to sense the occurrence of the filling of
the rectal vault. When the sensor detects the presence of feces
within the rectal vault, it signals the user or caregiver, allowing
bowel management without the attendant need for diapers.
[0007] 2. Description of Related Art
[0008] Fecal incontinence (FI) is the impaired ability to control
stool. Although not a life-threatening disease, symptoms are often
distressing and socially incapacitating. For patients who are under
nursing care, there is a labor cost associated with disposing of
fecal waste after a patient's incontinent episode and cleaning the
patient after the event. Other problems include the possible
excoriation of the patient's skin when it is exposed to fecal waste
for significant amounts of time, and the risk of contamination for
patients and nursing personnel from fecal material. Economically,
the replacement of soiled bed linens, blankets and gowns compounds
the loss of valuable nursing time and effort.
[0009] According to published reports, daily or weekly episodes of
fecal incontinence occur in approximately 2% of the adult
population and in about 7% of healthy, independent adults over the
age of 65. Fecal incontinence is second only to dementia as the
cause of institutionalization in the elderly and has been variously
estimated to affect between 32% to 47% of all nursing home
residents. In addition, FI accounts for expenses of over $400
million per year for adult diapers alone. The condition arises from
a number of causes including spinal bifida, dementia, obstetric
injury and side effects of anorectal surgery.
[0010] Minor degrees of fecal incontinence can be managed through
diet. For some patients, surgery and/or biofeedback treatment has
been used with success. For some patients, electrical stimulation
may be used or an artificial sphincter may be surgically implanted.
However, there are a large number of patients suffering from fecal
incontinence for whom medical therapy and/or surgical therapy have
either failed or are inappropriate due to the patient's medical
condition, circumstances, or personal choice.
[0011] U.S. Pat. No. 4,686,985 (Lottick) discloses an anal dilator
and occluder which has multiple chambers and which is inserted
partially into the rectum and inflated, thereby serving a dual role
of creating a controllable opening that can either block the
passage of stool, or can be used to widen a narrow anus, allowing
stool to pass. U.S. Pat. No. 4,979,947 (Berman) discloses an
encapsulated expanding device that is coated in a gelatin capsule
and is inserted into the rectum. When the gelatin capsule becomes
moist, it dissolves, allowing a compressed foam to expand, thereby
blocking the passage of stool. An attached string which comes out
of a hole in the abdominal wall can then be used to adjust the
position of the foam dam and allow feces to pass. The above two
inventions do not disclose a means to alert the user as to the need
to void the bowels. Since many patients suffer from nerve damage
and cannot sense the need to evacuate the bowels, leakage or other
undesirable effects may occur due to a prolonged retention of stool
within the rectal vault.
[0012] U.S. Pat. No. 5,695,484 (Cox) discloses an adhesive patch
for managing fecal incontinence by blocking seepage from the anus.
U.S. Pat. No. 6,096,057 (Klingenstein) discloses a fecal
incontinence device that uses external wings that are held in place
in the cleft of the buttocks by an expandible member that is
inserted into the rectum, with the combination said to block the
passage of feces. The problem with these approaches is that they do
not incorporate an alarming means to alert the user of the need to
evacuate the bowels. Left unattended, the devices can lead to
impaction of stool and attendant problems such as necrosis of
tissues in the anus and rectum.
[0013] U.S. Pat. No. 4,813,422 (Fisher et al) discloses a bowel
control probe apparatus and method for sensing and preventing
incontinent episodes. A deflated balloon catheter is inserted into
the rectal vault and is then inflated to serve as a dam to block
the passage of stool. At the tip of the catheter assembly is an
optical sensor that uses infrared technology to sense the presence
of stool. When fecal matter presses into an optical
emitter/detector sensor, it causes an alarm to alert the wearer or
caregiver that the bowels need attention. One disadvantage of the
device is that because fecal matter can cause permanent occlusion
of the optical sensor, the device must be discarded after each use.
For a patient who has multiple daily bowel movements, the cost can
be prohibitive.
[0014] U.S. Provisional Patent Application Ser. No. 60/313,540
(Brady) proposes a bowel incontinence treatment device having a
balloon catheter and annular electrode sensors to detect the
presence of fecal material. The problem with the design is that
annular electrodes are prone to nuisance tripping (false positives)
upon insertion and during wear.
[0015] The present invention solves the problems of the prior art
noted above.
BRIEF SUMMARY OF THE INVENTION
[0016] The present invention is of an apparatus for management of
fecal incontinence, comprising: means for blocking passage of stool
from a rectal vault by use of an inflatable balloon; means for
detecting an electrically conductive path that occurs between at
least two electrodes when they come into contact with fecal matter;
a non-conductive sleeve surrounding the electrodes; and means for
alarming a user or caregiver upon detection of the electrically
conductive path, thereby alerting the user or caregiver of a need
to evacuate the rectal vault.
[0017] The present invention is also of an apparatus for management
of fecal incontinence comprising a catheter having at least two
electrodes and an inflatable balloon, a non-conductive sleeve
surrounding the electrodes, and an alarm box, wherein the catheter
is insertable into a rectal vault and is inflatable to serve as a
block to passage of stool and wherein moisture sensed by the
electrodes triggers the alarm box and thereby notifies a user that
fecal material has entered the rectal vault. In the preferred
embodiment, an integrated circuit (preferably with a memory device)
is built into the catheter, the integrated circuit providing a
means to monitor an amount of time that the catheter is in use. A
moisture trace across the electrodes completes a voltage divider
and causes a comparator to change states. The non-conductive sleeve
is porous but impedes intrusion of moisture onto the electrodes,
thereby allowing sensitivity of the alarming means to be tailored
to different stool consistencies and reducing occurrences of false
alarms during insertion. The sleeve is preferably detachable and
designed for one time use, and comprises an external support flange
with flexible attachment guides configured so that when the balloon
is inflated, the attachment guides deform, causing the external
support flange and the balloon to move closer to each other and
serving to seat the balloon at an anorectal line, most preferably
wherein the external support flange provides a platform onto which
an absorbent pad may be added, thereby ensuring that seepage around
the balloon is reduced to reduce soiling of undergarments. In one
embodiment, the balloon deflates over a period of time to enforce a
minimum level of attention.
[0018] The present invention is further of a method for management
of fecal incontinence, comprising: blocking passage of stool from a
rectal vault by use of an inflatable balloon; detecting an
electrically conductive path that occurs between at least two
electrodes when they come into contact with fecal matter; employing
a non-conductive sleeve surrounding the electrodes; and alarming a
user or caregiver upon detection of the electrically conductive
path, thereby alerting the user or caregiver of a need to evacuate
the rectal vault. In the preferred embodiment, the blocking,
detecting, and employing steps are performed by a catheter. The
method preferably additionally comprises monitoring an amount of
time that the catheter is in use, most preferably employing an
integrated circuit comprising a memory device. In the detecting
step a moisture trace across the electrodes completes a voltage
divider and causes a comparator to change states. The
non-conductive sleeve is porous but impedes intrusion of moisture
onto the electrodes, thereby allowing sensitivity of alarming to be
tailored to different stool consistencies and reducing occurrences
of false alarms during insertion. Preferably the sleeve is
detachable and designed for one time use, and comprises an external
support flange with flexible attachment guides configured so that
when the balloon is inflated, the attachment guides deform, causing
the external support flange and the balloon to move closer to each
other and serving to seat the balloon at an anorectal line, most
preferably wherein the external support flange provides a platform
onto which an absorbent pad may be added, thereby ensuring that
seepage around the balloon is reduced to reduce soiling of
undergarments. In one embodiment, the method additionally comprises
permitting the balloon to deflate over a period of time to enforce
a minimum level of attention.
[0019] Other objects, advantages and novel features, and further
scope of applicability of the present invention will be set forth
in part in the detailed description to follow, taken in conjunction
with the accompanying drawings, and in part will become apparent to
those skilled in the art upon examination of the following, or may
be learned by practice of the invention. The objects and advantages
of the invention may be realized and attained by means of the
instrumentalities and combinations particularly pointed out in the
appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0020] The accompanying drawings, which are incorporated into and
form a part of the specification, illustrate one or more
embodiments of the present invention and, together with the
description, serve to explain the principles of the invention. The
drawings are only for the purpose of illustrating one or more
preferred embodiments of the invention and are not to be construed
as limiting the invention. In the drawings:
[0021] FIG. 1 is a diagram of the preferred catheter assembly of
the invention;
[0022] FIG. 2 is a diagram of the assembly as inserted into a
subject;
[0023] FIG. 3 is an electrical schematic of the assembly as
connected to conditioning electronics within a patient notification
device;
[0024] FIG. 4 is a diagram of the preferred catheter tip and sleeve
of the invention; and
[0025] FIG. 5 is a diagram of an alternate sleeve according to the
invention.
List of Reference numerals
[0026] 20--Dual lumen tube
[0027] 22--Balloon
[0028] 24--Valve
[0029] 26--Small lumen
[0030] 30--Tip assembly
[0031] 32--Electrical conductors
[0032] 34--Electrical connector
[0033] 35--Electrical connector
[0034] 36--Integrated circuit
[0035] 38--Sleeve assembly
[0036] 39--Sleeve holes
[0037] 40--Rectum
[0038] 42--Stool
[0039] 44--Anorectal line
[0040] 46--Comparator
[0041] 48--Resistor divider
[0042] 50--Reference resistor
[0043] 52--Comparator output
[0044] 54--Patient notification device
[0045] 55--Microcontroller
[0046] 56--First electrode
[0047] 58--Second electrode
[0048] 60--Thread
[0049] 62--Flatus vent hole
[0050] 64--External support flange
[0051] 66--Flexible attachment guides
[0052] 68--Tip covering
DETAILED DESCRIPTION OF THE INVENTION
[0053] The present invention is an apparatus and method for
managing fecal incontinence. The invention comprises use of a dual
lumen catheter with a balloon attached near the distal end. The
distal end of the catheter is inserted into the anus in a deflated
condition and once resident in the rectum it is inflated to a size
that blocks the passage of stool, serving the same function as the
sphincter. In the tip of the catheter are two electrodes. When a
moisture path is in place across these electrodes (indicative of
feces impinging onto the sensor) an electrical conduction takes
place that can be sensed in an attached alarm unit, thereby
alerting the user to the need to evacuate the bowels. Since the
electrodes are easily cleaned, the catheter may be reused multiple
times. For ambulatory patients, the mechanical barrier created by
the inflated balloon allows the user sufficient time to reach a
toilet, thus precluding an unintended passage of stool. Voluntary
evacuation is accomplished after deflating the balloon and removing
the catheter from the rectum. Once the rectum is emptied, the
catheter is reinserted and the balloon is reinflated.
[0054] In some embodiments, it will be desirable to use a "leaky"
balloon wherein either a calibrated leak is built into the valve
assembly that is used to inflate the balloon, or the balloon itself
is built of a slightly porous material through which the inflation
medium passes out gradually over time. The purpose of this is to
ensure that the device is not misused by leaving it unattended for
extended periods of time. A balloon that repeatably and reliably
deflates to an unusable small size over a period of, perhaps, four
hours, ensures that the device will receive periodic attention from
the user or caregiver.
[0055] The proximal end of the catheter assembly, which remains
outside of the body, has a built-in integrated circuit that keeps
count of the amount of time that the catheter is hooked into an
alarm box. This alarm box or "patient notification device" is worn
outside of the body and contains a battery and a microcontroller to
process data and to signal status via audible, visual or
vibrational means. Since the catheter maintains its own counter, an
expiration date can be enforced, thereby ensuring that the patient
does not wear the catheter for too long at a time or reuse it for
too many days.
[0056] In some embodiments, the inserted tip of the catheter will
have a detachable sleeve assembly that may be discarded after each
use. The sleeve has four functions. First, it allows the venting of
flatus through the center of the catheter without allowing the
intrusion of moisture. Second, it prevents nuisance tripping when
the catheter is first inserted, and during use, by preventing
moisture contact with the electrodes. Different sleeve designs may
be used for different patients in order to enhance fit and comfort,
and/or in order to accommodate different stool consistencies.
Third, in some embodiments, the sleeve facilitates insertion and
positioning. Finally, in some embodiments, the sleeve itself can
serve to block the passage of fecal material, thereby preventing
the soilage of clothing or bed linens that could occur due to
seepage around the catheter.
[0057] Making use of a relatively low cost, disposable sleeve is
desirable because that is the portion of the catheter that is
soiled with each use, and it is convenient to discard it with each
use while retaining the more costly catheter assembly for multiple
uses. In some embodiments, the sleeve itself might be incorporated
into the catheter assembly with the entire assembly being cleaned
after each use or with the entire catheter-sleeve assembly being
discarded after each use.
[0058] FIG. 1 depicts the catheter assembly consisting of a dual
lumen tube 20 to which a balloon 22 is attached on the distal end
and to which a valve 24 is attached on the proximal end. The small
lumen 26 within the tube 20 acts as the channel by which the
balloon 22 may be inflated and deflated. By attaching a syringe or
pump to the valve 24, air or another fluid may be forced
into/removed from the balloon 22. Two or more electrical conductors
32 also exit the tube 20 at the proximal end. These conductors 32
connect to electrodes 56,58 that are placed in the tip assembly 30
of the catheter. These conductors 32 connect to an electrical
connector 34. The electrical connector 34 will plug into an
externally worn Patient Notification Device (not shown). Also
attached to the electrical connector 34 are the leads from an
integrated circuit 36.
[0059] Although it is feasible to fill the balloon 22 with a liquid
such as saline or distilled water, when this is done, the weight of
the balloon will press upon nerves surrounding the sphincter muscle
and will be uncomfortable for many patients. Accordingly, the
balloon 22 will generally be filled by air. Air is readily
available and a balloon leak does not present serious problems. In
many applications, it will be desirable to implement a slow leak
that serves to deflate the balloon over time. This is to force the
user or caregiver to attend to the catheter on a periodic basis and
to not leave the device in situ for extended periods of time. A
leak can be implemented through a pinhole in the valve 24, or by
using a special material for the balloon that diffuses air over
time. For example, a silicone balloon with a deflated length of 1
inch, a deflated diameter of 0.5 inches, and a wall thickness of
0.020 inches, will attain a diameter of one inch with the injection
of 22 cc of air. After two hours, this diameter will be reduced to
0.7 inches due to the diffusion of air through the balloon
walls.
[0060] Over the tip 30 is fitted a detachable sleeve assembly 38.
This assembly serves to shield the electrodes 56,58 from direct
contact with the lining of the rectum. The sleeve assembly 38 has
slots through which fecal matter may enter in such a way as to
electrically bridge the electrodes 56,58, causing minute electrical
current leakages which are detected by a patient notification
device and used to signal an alarm.
[0061] FIG. 2 depicts the device as inserted into a subject. The
balloon 22 on the catheter inflates to approximately 20 cc, which
is a similar volume to that used with a conventional urinary
catheter. In normal use, a catheter with a deflated balloon is
inserted into the rectum into a position inside of the anorectal
line 44. It is then inflated. The present invention serves to
augment normal bowel function. Normal bowel function is controlled
by three things: anal sphincter pressure, rectal storage capacity
and rectal sensation. For a continent individual, the anal
sphincter muscle contracts to prevent stool from leaving the
rectum. Rectal storage occurs when the rectum 40 stretches to hold
stool. This storage can continue for some time after a person
becomes aware that the stool is present, allowing the person to
void the stool at a convenient time and place. Rectal sensation
tells the person that the stool is in the rectum 40. The device of
the present invention is targeted at subjects who are unable to
retain stool and/or unable to sense its presence. The balloon 22,
assists the sphincter to prevent stool from exiting the rectum.
Moisture from fecal matter that penetrates the sleeve assembly 38
is sensed, and this information is used to signal to the user or
caregiver that fecal matter has entered the rectal vault and needs
attention. Accordingly, the balloon 22 assists the sphincter in
retaining stool and the sensors/alarming serves as sensation.
[0062] FIG. 3 depicts an electrical schematic of the catheter
assembly as it is connected to conditioning electronics within a
Patient Notification Device 54. Two electrodes 56,58 are connected
through electrical conductors 32 to form the top leg of a voltage
divider that feeds into the noninverting input of a comparator 46.
When there is an open circuit across the electrodes 56,58, the
reference resistor 50 serves to ground the noninverting input of
the comparator 46. This causes the output 52 to be at a zero
potential. The resistor divider 48 is formed from equal resistances
and creates a reference point for the electrodes 56,58. When a
moisture path creates a resistance across electrodes 56,58 that is
less than the reference resistor 50, the output 52 of the
comparator 46 assumes a positive potential that is sensed by the
microcontroller 55. The microcontroller 55 can then trigger an
audible alarm, vibrator and/or visual indicator in response.
[0063] FIG. 3 depicts one possible electrical configuration for the
electrodes 56,58 and the integrated circuit 36, as it would be
implemented to reside in the catheter. The integrated circuit 36
that is depicted is a type 24LC00 serial EEPROM which is
manufactured by Microchip Technology Inc. This integrated circuit
is a memory device and has 16 bytes of read/write memory that is
accessed serially. The memory is nonvolatile and electrically
erasable. Each memory location is accessed serially using the SCL
(serial clock) and SDA (serial data) lines. The integrated circuit
36 attaches to a connector 34. This connector could be any standard
connector having five or more low voltage wires. For example, a
standard RJ45 telephone jack with six conductors would be suitable.
When the connector 34 is inserted into a patient notification
device, power is applied to integrated circuit 36 via the lines Vcc
and Vss. Prior to shipment to the end user, the integrated circuit
36 will be programmed with relevant information. This relevant
information could include a serial number, date of manufacture,
expiration date, total elapsed minutes of operation allowed, or
other information. When the integrated circuit 36 is connected to
the Patient Notification Device (PND) 54, the PND 54 continuously
monitors the state of the electrodes to see if fecal bridging
across the electrodes 56 and 58 has occurred. In addition,
periodically (for the sake of this discussion, once per minute),
the PND 54 reads the memory in integrated circuit 36, decrements
the minute counter and reprograms the integrated circuit 54 with
the new minute count. If the minute count reaches zero, then the
patient notification device 54 notifies the user, via a blinking
light or other indicator, that the catheter needs to be replaced.
The Patient Notification Device (PND) 54 also reads the expiration
date that is stored in the integrated circuit 54 and checks it
against the current date to see if the catheter has expired. The
unique serial number stored within the catheter allows a means to
identify product and manufacturing date in the case of recalls or
audit.
[0064] The Patient Notification Device has the size and appearance
of a conventional pager. Like a pager, it can be worn on a belt or
clipped to the clothes. Like a pager, it can notify the user or
caregiver by means of either an audible alarm or a vibration. The
PND is battery powered. It interfaces to the electrodes 56,58 at
the distal end of the catheter and senses a conductive path (due to
moisture) that occurs between the electrodes. It serves to amplify
and/or filter this signal to generate an alarm signal upon the
occurrence of feces being forced into the sleeve and bridging the
electrodes. The PND has an internal microcontroller and real time
clock. During the entire time that a catheter is attached to the
PND, at one minute intervals (or other appropriate intervals), the
PND will update the counter in the catheter with a minute (or other
appropriate) count. Alternatively, for some implementations, the
PND might decrement a minute counter in the catheter. Additionally,
in some implementations, the PND might read an expiration date from
the catheter and check this against the present date in order to
determine if the catheter is too old. The point of this is to
ascribe an expiration date to the catheter and/or a maximum usable
time frame. When the catheter is close to the expiration date or is
reaching the end of its usable life, the PND might sound an audible
alarm or flash an LED or otherwise indicate that the catheter
needed to be discarded in favor of a new catheter. One other
possible feature of the PND would be to sound an alarm if the
catheter has not been removed in two hours, three hours or some
arbitrary time interval, in order to ensure that the catheter
receives regular maintenance and attention and to minimize the
possibility for adverse events such as fecal impaction or necrosis
of tissues lining the rectal vault.
[0065] FIG. 4 depicts a detail of the catheter tip 30 and sleeve
38. Whereas the catheter body is a soft tube made of silicone or a
similar biologically inert, pliable substance, the tip is
relatively rigid and in some embodiments may be hollow in order to
accommodate the venting of flatus. The tip 30 has a ridge (or
thread) onto which a threaded sleeve may be screwed. The sleeve 38
is preferably injection molded out of a soft, biologically inert
material and, in some embodiments, will have a flatus venting hole
62 that is plugged with a material that is porous to gas but blocks
the intrusion of solids or liquids. Although in its preferred
embodiment, the sleeve 38 is designed to be detachable from the
catheter and disposable, it might be permanently affixed to the
catheter, and/or it might be designed for multiple use.
[0066] The sleeve 38 over the electrodes 56,58 operates to prevent
nuisance tripping. The sleeve design influences the speed with
which stool impinges upon the electrodes 56,58, causing a fecal
detection event. If the holes 39 in the sleeve are large, there is
little resistance and this style of sleeve might be appropriate for
patients with firm stool. Small holes offer more resistance and are
preferable for soft or watery stool.
[0067] The sleeve 38 in fact can have at least five functions.
First, it allows the venting of flatus through the center of the
catheter without allowing the intrusion of moisture. Second, it
prevents nuisance tripping when the catheter is first inserted into
the rectum, and during use, by impeding moisture contact with the
electrodes 56,58. Third, different sleeve designs may be used for
different patients in order to enhance fit and comfort, and/or in
order to accommodate different stool consistencies. Fourth, in some
embodiments, the sleeve 38 facilitates insertion and positioning.
Finally, in some embodiments, the sleeve 38 itself can serve to
block the passage of fecal material, thereby preventing the soilage
of clothing or bed linens that could occur due to seepage around
the inflated catheter.
[0068] FIG. 5 depicts a modified sleeve design that includes an
external support flange 64. Flexible attachment guides 66 connect
between the tip covering 68 and the support flange 64. When the
sleeve design is installed over a catheter, the flexible attachment
guides 66 will deform when the balloon is inflated, allowing for an
automatic seating of the inflated balloon at the anorectal line and
thereby blocking the unwanted leakage of stool by means of the
inflated balloon. In addition, the support flange 64 provides a
platform to which may be added an absorbent pad which can ensure
that any seepage around the balloon is controlled and does not soil
undergarments.
[0069] Although the invention has been described in detail with
particular reference to these preferred embodiments, other
embodiments can achieve the same results. Variations and
modifications of the present invention will be obvious to those
skilled in the art and it is intended to cover in the appended
claims all such modifications and equivalents. The entire
disclosures of all references, applications, patents, and
publications cited above are hereby incorporated by reference.
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