U.S. patent application number 11/117892 was filed with the patent office on 2005-08-25 for multi-lumen catheter with integrated connector.
Invention is credited to Cassidy, Kenneth T., Martel, Mark C., Wilson, Jon S..
Application Number | 20050187535 11/117892 |
Document ID | / |
Family ID | 31976744 |
Filed Date | 2005-08-25 |
United States Patent
Application |
20050187535 |
Kind Code |
A1 |
Wilson, Jon S. ; et
al. |
August 25, 2005 |
Multi-lumen catheter with integrated connector
Abstract
A multi-lumen catheter and method for inserting same into a
patient is disclosed. The catheter includes a multi-lumen catheter
tube having a distal end, a proximal end, and a plurality of lumens
therethrough. The catheter may include a single-lumen flush tube
portion, the flush tube portion having a proximal end and a distal
end, the proximal end of the flush tube portion being connected to
the distal end of the catheter tube such that the single lumen of
the flush tube portion is in fluid communication with each of the
lumens in the catheter tube. A connector is provided having a
proximal end, a distal end, and a longitudinal cavity extending
therethrough. The cavity includes a coupling portion near the
distal end of the connector, and the proximal end of the connector
is connected to the distal end of the flush tube portion or the
distal end of the catheter tube such that the cavity of the
connector is in fluid communication with the single lumen of the
flush tube portion or the plurality of lumens in the catheter tube.
The coupling portion of the cavity of the connector is configured
to receive a mating coupling portion of a medical device such as a
trocar. The catheter device facilitates the subcutaneous tunneling
of the catheter after catheter tip placement, and simultaneous
fluid communication with all of the multiple catheter lumens.
Inventors: |
Wilson, Jon S.;
(Winston-Salem, NC) ; Cassidy, Kenneth T.;
(Mocksville, NC) ; Martel, Mark C.; (Blues Creek,
NC) |
Correspondence
Address: |
AMSTER, ROTHSTEIN & EBENSTEIN LLP
90 PARK AVENUE
NEW YORK
NY
10016
US
|
Family ID: |
31976744 |
Appl. No.: |
11/117892 |
Filed: |
April 29, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11117892 |
Apr 29, 2005 |
|
|
|
10231577 |
Aug 30, 2002 |
|
|
|
Current U.S.
Class: |
604/523 |
Current CPC
Class: |
A61M 39/105 20130101;
A61M 2025/0037 20130101; A61M 39/12 20130101; A61M 2025/0031
20130101; A61M 25/0029 20130101; A61M 25/0069 20130101; A61M
2025/0019 20130101; A61M 25/0194 20130101; A61M 25/0097 20130101;
A61M 25/007 20130101; A61M 25/0028 20130101 |
Class at
Publication: |
604/523 |
International
Class: |
A61M 025/00 |
Claims
1. A multi-lumen catheter comprising: (a) a multi-lumen catheter
tube having a distal end, a proximal end, and a plurality of lumens
therethrough; (b) a flush tube portion, the flush tube portion
having a proximal end and a distal end, the proximal end of the
flush tube portion being connected to the distal end of the
catheter tube such that the single lumen of the flush tube portion
is in fluid communication with each of the lumens in the catheter
tube; and (c) a connector having a proximal end, a distal end, and
a central lumen extending therethrough, the central lumen including
a coupling portion, and the proximal end of the connector being
connected to the distal end of the flush tube portion such that the
central lumen of the connector is in fluid communication with one
lumen of the flush tube portion, wherein the coupling portion of
the cavity of the connector is configured to receive a mating
coupling portion of a tunneling device.
2. A multi-lumen catheter according to claim 1 wherein the catheter
tube, flush tube portion, and at least a portion of the connector
near its proximal end have substantially equal outer diameters.
3. A multi-lumen catheter according to claim 1 wherein the catheter
tube includes two lumens.
4. A multi-lumen catheter according to claim 1 further comprising a
plurality of single-lumen extension tubes, wherein the extension
tubes are connected to the proximal end of the multi-lumen catheter
tube such that each extension tube is in fluid communication with
one of the plurality of lumens in the catheter tube.
5. A multi-lumen catheter according to claim 4 wherein each
extension tube comprises a tube wall, and each tube wall includes
at least one opening therein configured to permit fluid flow into
or from one of the plurality of lumens in the catheter tube.
6. A multi-lumen catheter according to claim 4 wherein at least one
of the extension tubes is shorter in length than at least one other
extension tube.
7. A multi-lumen catheter according to claim 1 wherein the
connector is constructed of plastic or metal.
8. A multi-lumen catheter according to claim 1 wherein the coupling
portion of the connector includes a collar portion configured to
securely engage a groove in the coupling portion of the tunneling
device.
9. A multi-lumen catheter according to claim 1 wherein the coupling
portion of the connector includes a plurality of female threads
configured to securely engage a plurality of male threads on the
coupling portion of the tunneling device.
10. A multi-lumen catheter according to claim 1 wherein the
tunneling device is a trocar.
11. A multi-lumen catheter according to claim 1 wherein the
connector is configured to receive a mating coupling portion of a
syringe or other catheter flushing device.
12. A multi-lumen catheter according to claim 1 wherein the
connector includes a body having proximal end and a distal end, and
a spigot extending longitudinally from the proximal end of the
body, the spigot being sized and shaped for fitting engagement in
the distal end of the flush tube portion.
13. A multi-lumen catheter according to claim 12 wherein the spigot
is affixed in the flush tube portion by an adhesive.
14. A multi-lumen catheter according to claim 1 wherein the
proximal end of the flush tube portion is fused to the distal end
of the catheter tube.
15. A multi-lumen catheter according to claim 1 wherein the
connector has a substantially tapered outer shape wherein the
connector has a first outer diameter near its proximal end which is
larger than a second outer diameter near its distal end.
16. A multi-lumen catheter according to claim 15 wherein the first
outer diameter of the connector is substantially equal to an outer
diameter of the flush tube portion.
17. A multi-lumen catheter according to claim 1 wherein the
catheter tube includes a stabilizing cuff affixed to an outer
portion of the catheter tube.
18. A multi-lumen catheter according to claim 17 wherein the cuff
is affixed to the catheter at a position nearer to a distal end of
the catheter than to a proximal end of the catheter.
19. A multi-lumen catheter comprising: (a) a multi-lumen catheter
tube having a distal end, a proximal end, and a plurality of lumens
therethrough; and (b) a connector having a proximal end, a distal
end, and a coupling portion; wherein the proximal end of the
connector is connected to the distal end of the catheter tube, and
wherein the coupling portion of the connector is configured to
receive a mating coupling portion of a medical device.
20. A multi-lumen catheter according to claim 19 wherein the
connector further comprises a substantially longitudinal lumen
extending at least partially through the connector, wherein the
coupling portion is located in the lumen.
21. A multi-lumen catheter according to claim 19 wherein the
connector further comprises a plurality of prongs extending from
the proximal end of the connector and corresponding in number to
the plurality of lumens in the catheter tube, wherein each of the
prongs is engaged in one of the lumens at the distal end of the
catheter tube, thereby connecting the proximal end of the connector
to the distal end of the catheter tube.
22. A multi-lumen catheter according to claim 21 wherein the
multi-lumen catheter tube includes two lumens therethrough and the
connector includes two corresponding prongs.
23. A multi-lumen catheter according to claim 22 wherein the lumens
and prongs have corresponding D-shaped cross sections for mating
engagement therebetween.
24. A multi-lumen catheter according to claim 21 wherein the
connector comprises a substantially longitudinal lumen extending
from the distal end of the connector and at least partially through
the connector, and wherein each of the plurality of prongs includes
a substantially longitudinal passage therethrough, such that each
of the passages is in fluid communication with the substantially
longitudinal lumen in the distal end of the connector, thereby
providing a plurality of substantially parallel flow paths through
the connector from the distal end of the connector to the plurality
of lumens in the catheter tube.
25. A multi-lumen catheter according to claim 21 wherein each of
the prongs is adhesively attached to inner walls of one of the
lumens at the distal end of the catheter tube.
26-38. (canceled)
Description
BACKGROUND OF THE INVENTION
[0001] 1) Field of the Invention
[0002] The present invention relates generally to medical
instrumentation and more specifically to a multi-lumen catheter
with an integrated connector that facilitates the subcutaneous
tunneling of the catheter after catheter tip placement, and
simultaneous fluid communication with all of the multiple catheter
lumens.
[0003] 2) Description of the Prior Art
[0004] Catheters, generally, are hollow, flexible tubes for
insertion into a body cavity, duct, or vessel to allow the passage
of fluids or distend a passageway. Catheters are often used for
temporary or long-term dialysis treatment. Dialysis treatment
provides for blood to be withdrawn from the patient, purified, and
then returned to the patient. Thus, in dialysis treatment,
catheters are used to allow passage of a patient's blood into and
out of the patient's body. For optimal performance during dialysis
treatment, the catheter tips, both in-flow and out-flow, should be
placed in close proximity to the heart. Typically, medical
personnel use either a double lumen catheter or two single lumen
catheters. Both types, however, present certain deficiencies.
[0005] While double lumen catheters (e.g., U.S. Pat. No. 4,895,561)
allow for a single venous insertion of the catheter into the
desired vein, double lumen catheters typically do not permit
optimal catheter tip placement. Due to differences among patients,
optimal tip position varies from patient to patient. Non-optimal
tip position may significantly lower flow values, resulting in less
effective dialysis treatment. For current double lumen catheters, a
physician must make an estimate regarding the appropriate catheter
tube length prior to beginning the procedure of catheterization.
Then, a subcutaneous tunnel is made from the preferred end position
of the hub assembly, namely, away from the neck of the patient in
order to allow for more convenient access to the dialysis treatment
equipment. The double lumen catheter tube is then tunneled
forwardly and the tips of the catheter are inserted into the area
to be catheterized. The estimated catheter tube length and
subsequent forward tunneling may result in less than optimal tip
placement.
[0006] With the use of two independent catheters (e.g., U.S. Pat.
No. 5,776,111 to Tesio) the problem of tip placement is addressed.
The hub assembly of each catheter is removable from the tube and
tip portion of the catheter, thereby allowing the catheter tip to
be placed directly into the vein and advanced into the desired
position. Then, the proximal end of the catheter can be reversed
tunneled and trimmed to a desired length. Thereafter, the hub
assembly is attached. Deficiencies, however, exist in this method
of catheterization as well. One problem associated with this method
is that this method requires two separate venous insertions,
namely, two tunnels and two of each accessory instrument used for
the procedure. Therefore, there is increased surgical time required
to place two catheters, there are two wound entry sites which
doubles the risk of post-surgical infection, and the two catheters
together are significantly larger in diameter than one double lumen
catheter.
[0007] Applicant's co-pending application Ser. No. 09/769,052,
filed Jan. 24, 2001, and Ser. No. 10/086,033, filed Feb. 28, 2002,
disclose a multi-lumen catheter apparatus and method for inserting
the apparatus in a patient. The disclosures of these co-pending
applications are hereby incorporated by reference. In the disclosed
apparatus and method, a multi-lumen catheter includes a selectively
attachable hub assembly that allows the catheter tip to be
positioned accurately within a patient's vein prior to subcutaneous
tunneling. The distal end of the catheter tube is selectively
attachable to the hub assembly. Accordingly, after the tips of the
catheter have been accurately positioned in a patient, the other
end of the catheter may be reverse tunneled under the skin of a
patient. Specifically, after tip placement, an incision is made in
the skin adjacent to the point where the protruding distal end of
the catheter exits the skin. A subcutaneous tunnel is then formed
having a first end at the incision and a second end exiting the
skin at a point remote from the first end of the tunnel. The distal
end of the catheter tube is passed through the subcutaneous tunnel
and a tissue stabilizing cuff is seated therein, thereby
stabilizing the tunneled portion of the catheter tube in the
patient. A selectively attachable hub assembly is connected to the
lumens at the distal tip of the catheter tube for subsequent
connection of the catheter to a dialysis machine.
[0008] During the above procedure, guiding the distal end of the
catheter tube through the subcutaneous tunnel can be problematic.
It is known to engage the end of the catheter tube to a trocar
extending through a subcutaneous tunnel for guiding the catheter
tube through the tunnel with the trocar. Typically, however, a tip
of the trocar includes barbs, ridges, threads, or the like for
insertion into one of the lumens at the distal end of the catheter
tube, thereby forming a friction or interference fit between the
interior surface of the catheter and the barbs or ridges on the tip
of the trocar. Unfortunately, the frictional engagement between the
trocar tip and the catheter tube may be insufficient to withstand
forces exerted on the catheter tube as the tube and adjoined trocar
are passed through the tunnel, thereby causing the catheter tube to
loosen and separate from the trocar. Also, because such a trocar
engages only one lumen of a multi-lumen catheter, the shaft of the
trocar and the catheter tube are not concentrically aligned,
thereby forming a discontinuity which can impede passage of the
trocar and adjoined catheter tube through the tunnel, and thereby
increasing the likelihood of separation between the trocar and
catheter tube.
[0009] The inventors are aware of a tunneling device that includes
a trocar with a threaded tip for engagement in a connector that is
releasably attached to the distal end of a multi-lumen catheter
tube. One problems with this device included is that the connector
is difficult to manipulate because of its small size. Also, use of
this tunneling device necessarily required multiple steps,
including: a) connecting one end of the connector to the end of the
catheter tube; and b) connecting the other end of the connector to
the tip of the trocar so that the catheter can be routed through a
subcutaneous tunnel with the trocar. Though this tunneling device
has proven to be adequately secure in most instances, the nature of
the releasable attachment does not completely eliminate the
possibility that the connector may disengage from the catheter tube
as the connector and tube are guided through a subcutaneous tunnel
via the trocar.
[0010] Therefore, there is a need for an improved connection
between the trocar and the distal end of a multi-lumen catheter
tube which provides more positive and aligned engagement between a
trocar and the distal end of a multi-lumen catheter tube for
guiding the catheter tube through a subcutaneous tunnel with a
minimal number of separate component parts and process steps.
[0011] Another shortcoming of known apparatus and methods for
catheterization of patients with multi-lumen catheters is the need
to individually flush each of the multiple lumens of the catheter
with a flushing solution to clear the lumens of debris, tissue, or
the like prior to connection of the catheter to a dialysis machine.
Flushing the lumens in a sequential manner adds time to the
catheter insertion procedure. Known multi-lumen catheter systems
described above also require sequential flushing of each of the
multiple catheter lumens. Therefore, there is a need for an
apparatus and method which permit simultaneous flushing of multiple
catheter lumens in a multi-lumen catheter system.
SUMMARY OF THE INVENTION
[0012] A multi-lumen catheter includes a multi-lumen catheter tube
having a distal end, a proximal end, and a plurality of lumens
therethrough. The catheter may also include a single-lumen flush
tube portion having a proximal end and a distal end. The proximal
end of the flush tube portion is connected to the distal end of the
catheter tube such that the single lumen of the flush tube portion
is in fluid communication with each of the lumens in the catheter
tube. The catheter further includes a connector having a proximal
end, a distal end, and a longitudinal cavity extending
therethrough. The cavity includes a coupling portion near the
distal end of the connector, and the proximal end of the connector
is connected to the distal end of the flush tube portion such that
the cavity of the connector is in fluid communication with the
single lumen of the flush tube portion. The coupling portion of the
cavity of the connector is configured to receive a mating coupling
portion of a trocar. The multi-lumen catheter tube, flush tube
portion, and at least a portion of the connector near its proximal
end may have substantially equal outer diameters. The multi-lumen
catheter tube may include two lumens. A plurality of single-lumen
extension tubes may be connected to the proximal end of the
multi-lumen catheter tube such that each extension tube is in fluid
communication with one of the plurality of lumens in the catheter
tube. Each extension tube may include a tube wall having at least
one opening configured to permit fluid flow into and from the
catheter. At least one of the extension tubes may be shorter in
length than at least one other extension tube.
[0013] The connector may be constructed of a material such as
plastic, metal, or the like. The coupling portion of the connector
cavity may include a collar portion configured to securely engage a
groove in a coupling portion of a mating medical device.
Alternatively, the coupling portion of the connector cavity may
include a plurality of female threads configured to securely engage
a plurality of male threads on a coupling portion of a mating
medical device. The coupling portion of the connector may be
configured for secure connection to a trocar, a syringe or other
flushing device, or the like. The multi-lumen catheter may also
include a stabilizing cuff on an outer portion of the catheter
tube.
[0014] The connector also may include a body having proximal end
and a distal end, and a spigot extending longitudinally from the
proximal end of the body. The spigot may be sized and shaped for
fitting engagement in the single lumen at the distal end of the
flush tube portion, and the spigot may be affixed in the single
lumen of the flush tube portion by a suitable adhesive. The
connector may have a substantially tapered outer shape wherein the
connector has a first outer diameter near its proximal end which is
larger than a second outer diameter near its distal end. The first
outer diameter of the connector may be substantially equal to an
outer diameter of the flush tube portion, and the proximal end of
the flush tube portion may be fused to the distal end of the
catheter tube such as by heat welding or the like. A tissue
in-growth stabilizing cuff may be affixed to an outer portion of
the catheter tube. Preferably, the cuff may be positioned nearer to
the distal end of the catheter than to the proximal end of the
catheter.
[0015] In another arrangement, a multi-lumen catheter includes a
multi-lumen catheter tube having a distal end, a proximal end, and
a plurality of lumens therethrough, and a connector having a
proximal end, a distal end, a plurality of prongs longitudinally
extending from the proximal end of the connector. The plurality of
prongs correspond in number to the plurality of lumens in the
catheter tube. A longitudinal cavity is provided in the distal end
of the connector and includes a coupling portion in the cavity.
Each of the prongs is engaged in one of the lumens at the distal
end of the catheter tube, thereby connecting the proximal end of
the connector to the distal end of the catheter tube. The coupling
portion of the longitudinal cavity of the connector is configured
to receive a mating coupling portion of a medical device. The
multi-lumen catheter tube may include two lumens therethrough and
the connector may include two corresponding prongs. Where two
lumens and two prongs are included, the lumens and prongs may have
corresponding D-shaped cross sections for mating engagement
therebetween. Each of the prongs may include a longitudinal passage
therethrough, such that each of the passages is in fluid
communication with the longitudinal cavity in the distal end of the
connector. The passages and cavity combine to provide a plurality
of substantially parallel flow paths through the connector from the
distal end of the connector to the plurality of lumens in the
catheter tube. Each of the prongs may be adhesively attached to
inner walls of a corresponding lumen at the distal end of the
catheter tube. Alternatively, each of the prongs may include a
non-smooth outer contour, thereby providing a frictional fit
between each of the prongs and inner walls of a corresponding lumen
at the distal end of the catheter tube.
[0016] A trocar is provided which is configured for forming a
subcutaneous tunnel and for secure engagement with the connector.
The trocar may include a shaft having a handle end and an insertion
end. The insertion end of the trocar may include a substantially
tapered portion and an insertion tip. The trocar may further
include a circumferential groove in the substantially tapered
portion of the shaft near the insertion tip, wherein the
circumferential groove is configured for secure engagement with an
integrated connector on a distal end of a catheter. The trocar may
also include a plurality of spiral grooves or threads in the
substantially tapered portion of the shaft proximate the
circumferential groove, the grooves or threads being configured to
advance the insertion tip of the trocar into a bore in the
integrated connector as the trocar is rotated relative to the
connector. The handle end of the trocar may include a handle
configured to be gripped by a person's hand.
[0017] A method is also provided for inserting and securing a
multi-lumen catheter as described above in a patient. The method
includes making an incision and inserting a proximal portion of the
catheter into a body cavity or blood vessel such that distal
portions of the multi-lumen catheter tube, the flush tube portion,
and the connector extend outwardly from the patient through the
first incision. A subcutaneous tunnel is formed having a first end
proximate to the incision, and an opposed second end which is
remote from the first end. A trocar is inserted through the tunnel
such that at least a portion of the trocar protrudes from the first
end of the tunnel. The trocar includes a coupling portion near a
protruding tip of the trocar, and the coupling portion of the
trocar is engaged in the coupling portion of the connector. The
connector, the flush tube portion, and at least a portion of the
distal end of the catheter tube are guided through the tunnel and
out through the second end of the tunnel with the trocar until the
catheter tube is finally positioned within the tunnel. The
connector and engaged trocar, the flush tube portion, and a portion
of the catheter tube near its distal end are severed from a
remaining portion of the catheter tube once the catheter is in a
final position.
[0018] Optionally, the catheter tube installed by the above method
may include an in-growth stabilizing cuff affixed to a portion of
an outer surface of the protruding distal portion of the catheter
tube. When a stabilizing cuff is included on the catheter tube, the
method may further include dilating a portion of the tunnel between
the first end of the tunnel and a cuff seating point in the tunnel.
A portion of the tunnel may be dilated by sliding a sheath dilator
having a hollow bore over the insertion tip of the trocar and
guiding the sheath dilator along the shaft of the trocar and into
the first end of the tunnel. In this arrangement, the sheath
dilator includes an outer dilating surface which has a larger
diameter than a diameter of the trocar shaft. The sheath dilator is
passed along the trocar and into the tunnel until the tunnel is
sufficiently dilated between its first end and the cuff seating
point. A catheter tube with a stabilizing cuff is seated in the
tunnel when the stabilizing cuff is positioned at the cuff seating
point in the tunnel. In another embodiment, the method may further
include flushing the catheter lumens by injecting a flushing liquid
through the distal end of the connector, the connector cavity, and
the flush tube portion before engaging the coupling portion of the
trocar in the coupling portion of the connector.
[0019] In order to provide distal portions of the catheter with a
smooth outer profile to facilitate uninterrupted passage of the
catheter through the subcutaneous tunnel, a tapered sheath may be
placed around the connector and at least a portion of the adjoined
flush tube portion. Preferably, the sheath includes a hollow bore
for sliding engagement over the connector and flush tube portion, a
tapered portion proximate to a distal end of the sheath, and a
smooth outer surface. The smoothly-contoured sheath covers at least
portion of the trocar shaft, the connector, and at least a portion
of the flush tube portion, thereby covering and smoothing the
discrete transitions between the adjoined components of the
tunneling assembly. Placement of the sheath may include
back-fitting the sheath over the trocar before engaging the
coupling portion of the trocar in the coupling portion of the
connector, and sliding the sheath over at least a portion of the
trocar, the connector, and at least a portion of the flush tube
portion.
[0020] For connecting the multi-lumen catheter to a fluid
management device, the method may include providing a selectively
attachable hub assembly including a hub body with a distal portion
and a proximal portion. The proximal portion of the hub body is
selectively attached to a distal portion of the remaining portion
of the multi-lumen catheter tube. The proximal portion of the hub
assembly is attached to a fluid management device.
[0021] A compression cover and compression sleeve can be preloaded
onto the trocar by placing the compression cover and the
compression sleeve axially over the tip of the trocar. A
protrusion, such as a small piece of tape, can be wrapped around
the trocar between the tip 42 and the preloaded compression cover
and compression sleeve from inadvertently sliding off the trocar
before the trocar and the connector are connected. Before the
connector, flush tube portion, and distal portion of the catheter
tube are severed from the remainder of the catheter tube, the
compression cover and the compression sleeve are moved from the
trocar onto the distal portion of the catheter tube.
[0022] The invention also provides a method for replacing a
multi-lumen catheter tunneled as described above in a patient. The
replacement method includes withdrawing distal portions of the
catheter tube from the subcutaneous tunnel through the first end of
the tunnel, and withdrawing the proximal end of the multi-lumen
catheter tube from the patient. A replacement multi-lumen catheter
is provided which includes a multi-lumen catheter tube having a
proximal end with proximal tips and a distal end, a single-lumen
flush tube portion having a proximal end connected to the distal
end of the catheter tube and a distal end, and an integrated
connector including a coupling portion on a distal end of the
connector and having a proximal end connected to the distal end of
the flush tube portion. The proximal end of the catheter tube of
the replacement multi-lumen catheter is inserted through a
replacement incision in the patient's skin proximate to the first
end of the tunnel, and the proximal tips of the replacement
multi-lumen catheter are placed in the patient such that a distal
portion of the multi-lumen catheter tube, the flush tube portion,
and the connector of the replacement multi-lumen catheter extend
outwardly from the patient through the replacement incision. A
trocar is extended through the subcutaneous tunnel such that at
least a portion of the trocar protrudes from the patient through
the first end of the tunnel, wherein the trocar includes a coupling
portion near a protruding tip of the trocar. The coupling portion
of the trocar is engaged in the coupling portion of the connector
of the replacement multi-lumen catheter. The connector, the flush
tube portion, and at least a portion of the distal end of the
catheter tube of the replacement multi-lumen catheter are guided
through the tunnel and out through the second end of the tunnel
with the trocar until the replacement catheter tube is finally
positioned in the tunnel. The connector and engaged trocar, the
flush tube portion, and a distal portion of the multi-lumen
catheter tube of the replacement multi-lumen catheter are severed
from a remaining portion of the multi-lumen catheter tube of the
replacement catheter. The replacement catheter is then connected to
a fluid management device.
[0023] These and other aspects of the invention will be made clear
from a reading the following detailed description together with the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a perspective view of a multi-lumen catheter with
an integrated connector;
[0025] FIG. 2 is a cross-sectional view of a distal portion of the
catheter of FIG. 1 taken through a longitudinal axis of the
catheter shown in FIG. 1;
[0026] FIG. 3 is an enlarged perspective view of an integrated
connector for the catheter of FIG. 1;
[0027] FIG. 4 is an elevation view of a trocar for use with the
catheter of FIG. 1;
[0028] FIG. 5 is an enlarged view of the insertion tip portion of
the trocar of FIG. 4;
[0029] FIG. 6 is a cross-sectional detail of the insertion tip
portion of a trocar engaged in a coupling portion of an integrated
connector;
[0030] FIG. 7 is a cross-sectional detail view of an alternative
coupling arrangement for a trocar and connector;
[0031] FIG. 8 is a cross-sectional view showing a flushing
arrangement for the catheter of FIG. 1;
[0032] FIGS. 9A-9D illustrate a method of inserting a multi-lumen
catheter with an integrated connector as shown in FIG. 1 into a
patient;
[0033] FIG. 10 is a partial sectional view of a sheath dilator that
slides along a trocar to dilate a portion of a subcutaneous tunnel
in a patient;
[0034] FIG. 11 is cross-sectional view of a sheath assembled about
an interconnected trocar, connector, and flush tube portion;
[0035] FIG. 12 is a perspective view of another embodiment of a
multi-lumen catheter with an integrated connector;
[0036] FIG. 13 is a partial cross-sectional view of the multi-lumen
catheter of FIG. 12 showing details of a construction for the
distal end of the catheter;
[0037] FIG. 14 is a perspective view of the connector portion of
the catheter shown in FIGS. 12 and 13; and
[0038] FIG. 15 is a cross-sectional view taken through line I-I as
shown in FIG. 13.
DETAILED DESCRIPTION
[0039] For the purposes of the following description and the claims
appended hereto, the relative term "proximal" refers to those
portions of a catheter and components of the catheter which are
nearest the insertion end of the catheter as it is inserted into an
area of a patient's body being catheterized such as a blood vessel.
Conversely, the relative term "distal" refers to those portions of
a catheter and components of the catheter which are farthest from
the insertion end of the catheter.
[0040] An embodiment of a multi-lumen catheter 10 is shown in FIG.
1. The catheter 10 includes a multi-lumen catheter tube 16, a flush
tube portion 14, and a connector 12. The catheter 10 includes a
proximal end 10p and a distal end 10d. Similarly, each of the
catheter components also include proximal and distal portions as
follows: catheter tube 16 includes a proximal end 16p and a distal
end 16d; flush tube portion 14 includes a proximal end 14p and a
distal end 14d; and connector 12 includes a proximal end 12p and a
distal end 12d as shown in FIG. 1.
[0041] FIG. 2 shows a longitudinal cross-section of catheter 10. As
shown in FIG. 2, catheter tube 16 includes a plurality of lumens
through its length. Preferably, catheter tube 16 is resiliently
flexible and preferably has a substantially cylindrical outer
shape. The proximal end 14p of flush tube portion 14 is connected
to the distal end 16d of catheter tube 16 as shown. The single
lumen 28 of flush tube portion 14 is in fluid communication with
each of the lumens 30 of the catheter tube 16. Flush tube portion
14 is also preferably flexibly resilient and preferably has a
substantially cylindrical shape. Catheter tube 16 and flush tube
portion 14 preferably have substantially equal outer diameters.
Preferably, the proximal end 14p of flush tube portion 14 is heat
welded to the distal end 16d of catheter tube 16 such that the
junction has a substantially smooth and continuous outer
contour.
[0042] As shown in FIG. 1, the proximal end of the catheter 10 may
include a plurality of single-lumen extension tubes 19, 23. Each
extension tube 19, 23 is connected to the proximal end 16p of the
multi-lumen catheter tube 16 such that the single lumen of each
extension tube 19, 23 is in fluid communication with one of the
lumens 30 of the catheter tube 16. The extension tubes 19, 23 have
outer walls, which may include one or more openings 20, 21 therein
to provide for fluid flow into or from the extension tubes
19,23.
[0043] The proximal end 12p of the connector 12 is connected to the
distal end 14d of the flush tube portion 14. A longitudinal cavity
or bore 22 extends through the length of the connector 12 as shown
in FIG. 2. The cavity 22 is in fluid communication with the single
lumen 28 of the flush tube portion 14. Preferably, the proximal end
12p of the connector 12 includes a longitudinal spigot 26 as shown
in FIG. 2. Preferably, spigot 26 has an outer diameter which is
substantially equal to an inner diameter of the lumen 28 at the
distal end 14d of the flush tube portion 14. The spigot 26 is
matingly engaged in the lumen 28 as shown in FIG. 2. An adhesive 34
may affix the spigot 26 in the distal end 14d of the flush tube
portion 14. Preferably, the proximal end 12p of the connector 12
has an outer diameter that is substantially equal to the outer
diameter of the distal end 14d of the flush tube portion 14. The
outer profile of the connector 12 may be tapered as indicated in
FIG. 2, wherein the outer diameter at the proximal end 12p of the
connector 12 is larger than the outer diameter of the connector 12
at its distal end 12d.
[0044] Connector 12 includes a coupling portion 24 near its distal
end 12d. The coupling portion 24 is configured for secure mating
engagement with a corresponding coupling portion of a medical
device such as a trocar, a syringe, or the like. Coupling portion
24 of the connector may include a circumferential collar 32 as
shown in FIGS. 2 and 3.
[0045] FIG. 4 shows a trocar 40 which may be used with the
multi-lumen catheter 10 described above. The trocar 40 includes a
shaft 41 having an insertion end or tip 42 and a handle end 44. A
handle 46 is preferably provided which is configured to be securely
gripped in a persons hand. As shown in FIG. 4, the trocar 40 may be
constructed from a single piece of ductile or malleable material
such as stainless steel or the like. The portion of the shaft 41
near the insertion tip 42 of the trocar 40 is preferably tapered as
shown, and culminates in a pointed or slightly rounded tip 42. The
trocar 40 may have any configuration which is can be used to form a
subcutaneous tunnel in a patient suitable for receiving the
catheter 10. As shown in FIG. 5, the trocar 40 includes a coupling
portion 48 near the insertion tip 42. Preferably, the coupling
portion 48 includes a circumferential groove 49. The groove 49 is
sized and shaped to be engaged with the collar 32 of the connector
12 as shown in FIG. 6. The collar 32 snaps into the groove 49 as
the insertion tip 42 of the trocar 40 is inserted into the open end
of the cavity 22 at the distal end 12d of the connector 12, thereby
lockably engaging the coupling portions 48, 24 of the trocar 40 and
connector 12. Alternatively, as shown in FIG. 5, spiral grooves 47
or threads may be provided on the insertion tip 42 adjacent to the
groove 49. By rotating the shaft 41 of the trocar 40 relative to
the connector 12, the spiral grooves 47 act to advance the
insertion tip 42 into the connector 12 until the groove 49 is in
position to engage the collar 32.
[0046] In an alternative arrangement as shown in FIG. 7, the
coupling portion 24 of the connector 12 may include a plurality of
female threads 52. Alternatively, the connector 12 may not be
threaded, and the male threads of the trocar 40 could be self
tapping. Correspondingly, the coupling portion 48 of the trocar 40
may include a plurality of mating male threads 50. The male threads
50 are threaded into the female threads 52 to lockably engage the
trocar 40 in the connector 12. Once lockably engaged in the
connector 12, the trocar 40 can be used to guide the catheter 10
through the tunnel 106.
[0047] The connector 12 and flush tube portion 14 permit the
simultaneous flushing of the multiple lumens 30 of the catheter
tube 16 with a flushing liquid 62. As shown in FIG. 8, a tip of a
syringe 60 or other flushing device may be inserted into the
coupling portion 24 at the distal end 12d of the connector 12.
Flushing liquid 62, such as a saline solution, can be injected
through the cavity 22 of the connector 12, through the single lumen
28 of the flush tube portion 14, and into each of the lumens 30 of
catheter tube 16. In this way, each of the plurality of catheter
lumens 30 need not be separately flushed in a sequential manner,
thereby saving both time and effort during the catheterization
process.
[0048] An alternative embodiment 410 of a multi-lumen catheter is
shown in FIGS. 12-15. This embodiment 410 is similar to the
embodiment 10 described above, but does not include a flush tube
portion. As shown in FIG. 12, the connector 412 is connected
directly to the distal end 416d of the multi-lumen catheter tube
416. The proximal end 410p of the multi-lumen catheter 410 may
include a plurality of single-lumen extension tubes 419, 423. Each
extension tube 419, 423 is connected to the proximal end 416p of
the multi-lumen catheter tube 416 such that the single lumen of
each extension tube 419, 423 is in fluid communication with one of
the lumens of the multi-lumen catheter tube 416. The extension
tubes 419, 423 have outer walls, which may include one or more
openings 420, 421 therein to provide for fluid flow into or from
the extension tubes 419, 423. A stabilizing cuff 415 may be
provided on the catheter 410 as shown in FIG. 12.
[0049] As shown in FIGS. 13-15, the connector 412 is adapted to
engage the multiple lumens 430 of the catheter tube 416. The
connector 412 may include a plurality of prongs 426, 427 extending
longitudinally from its proximal end 412p. One or more slots 470
may divide the prongs 426, 427. To affix the connector 412 to the
distal end 416d of the catheter tube 416, the prongs 426, 427 are
engaged in the lumens 430 as shown in FIG. 13. The prongs 426, 427
may be permanently joined to the catheter tube 416 with a suitable
adhesive. Alternatively, the prongs 426, 427 may be sized slightly
larger than the lumens 430 and/or may include non-smooth outer
surfaces (such as circumferential ridges, barbs, grooves, or the
like) to form a frictional fit between the inner walls of the
lumens 430 and the prongs 426, 427 (not shown).
[0050] In order to permit simultaneous flushing of the multiple
lumens 430, longitudinal passages 440, 442 may be provided through
each of the prongs as shown in FIG. 13. Each of the passages 440,
442 is in fluid communication with a longitudinal cavity 422 in the
distal end 412d of the connector 412. In this arrangement, a
plurality of substantially parallel flow-paths are defined through
the connector 412 from its distal end 412d to the adjoining lumens
430 in the catheter tube 416. The distal end 412d of the connector
412 may be substantially the same as the embodiment 12 of the
connector as described above and shown in FIGS. 2, 3, and 6-8. For
example, as shown in FIG. 13, the connector 412 may include a
circumferential collar 432 in its cavity 422 for mating engagement
with a trocar 40 as described above.
[0051] When the multi-lumen catheter tube 416 includes two lumens
430, the lumens 430, prongs 426, 427, and passages 440, 442 may
have corresponding substantially D-shaped cross sections as shown
in FIG. 15. In this arrangement, the D-shaped lumens 430 are
separated by a divider wall or septum 460 which is received in a
slot 470 between the D-shaped prongs 426, 427. A catheter 10, 410
like that described above can be used in an improved method of
inserting a multiple-lumen catheter into a patient. One embodiment
of such a method is sequentially illustrated in FIGS. 9A-9D. While
the method is described in terms of inserting embodiment 10 of the
catheter as described in detail above, the improved method can also
be used for inserting alternate embodiment 410 of the multi-lumen
catheter or any other similarly constructed catheter having an
integrated connector on its distal end. As shown in FIG. 9A, the
proximal tips 20, 21 of the catheter 10 are accurately placed in a
patient's blood vessel through an incision 100 in the patient's
skin. After tip placement, distal portions of the catheter 10
protrude from the patient's skin at the incision 100, including the
distal tip 10d, the connector 12, the flush tube portion 14, and
the distal end 16d of the catheter tube 16. As also shown in FIG.
9A, a subcutaneous tunnel 106 is formed using the trocar 40. The
tunnel 106 includes a first end 102 and a second end 104. The first
end 102 is preferably coincident with the incision 100. At this
point, the multiple lumens 30 of the catheter tube 16 may be
simultaneously flushed with a flushing liquid 62 using a syringe 60
or the like as shown in FIG. 8. Note that the trocar 40 is
positioned in the tunnel 106 such that the insertion tip of the
trocar protrudes from the first end 102 of the tunnel 106 as shown
in FIG. 9A.
[0052] Referring to FIG. 9B, the insertion tip 42 of the trocar 40
is inserted into the distal tip 10b of the catheter 10 and into the
cavity 22 of the connector 12 to lockably engage the coupling
portion 48 of the trocar 40 with the mating coupling portion 24 of
the connector 12 as shown in detail in FIG. 6. Once the connector
12 and trocar 40 are connected, the connector 12, flush tube
portion 14, and the distal end 16d of the catheter tube 16 are
guided and drawn through the tunnel 106 with the trocar 40 as shown
in FIG. 9C. Preferably, the distal end 16d of the catheter tube 16
is drawn sufficiently through the tunnel 106 such that no portion
of the catheter tube 16 protrudes from the patient at the incision
100 at the insertion point.
[0053] An outer portion of the catheter tube 16 may include a
tissue in-growth stabilizing cuff 15 for stabilizing the inserted
catheter 10 in the patient. Referring to FIG. 9D, when the catheter
10 includes a stabilizing cuff 15, a portion 130 of tunnel 106 may
be dilated to enlarge the width of the tunnel 106 to better receive
the cuff 15 as the catheter 10 is drawn through the tunnel 106. As
shown in FIG. 10, the dilated portion 130 of the tunnel is
preferably dilated by sliding a sheath dilator 200 over the
insertion tip 42 and along shaft 41 of the trocar 40 when the
trocar 40 is positioned in the subcutaneous tunnel 106. The sheath
dilator 200 preferably includes a hollow bore 208, a tapered
leading end 206, a substantially cylindrical portion 204, and a
handle 202. The sheath dilator 200 is inserted through the first
end 102 of the tunnel 106 and into the tunnel 106 until the tip 206
has been inserted proximate to a cuff seating point 104 in the
tunnel 106 to form a dilated portion 130 of the tunnel 106. Once
the dilated portion 130 is sufficiently dilated, the sheath dilator
200 is removed from the tunnel 106 and the trocar 40. The insertion
tip 42 of the trocar 40 is then engaged with the connector 12 as
shown in FIG. 9B, and the distal end 10b of the catheter 10 is
drawn sufficiently through the tunnel 106 such that the cuff 15
seats at an end 140 of the dilated portion 130 of the tunnel 106 as
shown in FIG. 9D.
[0054] As shown in FIG. 11, a sheath 300 may be placed over outer
portions of the interconnected trocar 40, connector 12, and flush
tube portion 14 to facilitate passage of distal portions of the
catheter 10 through a subcutaneous tunnel 106. The sheath 300
preferably includes a hollow bore 301, a tapered outer portion 302,
and a cylindrical outer portion 304. In order to assemble the
sheath 300 as shown, the sheath 300 is back-fitted over the shaft
41 of the trocar 40 before the trocar 40 is engaged with the
connector 12 (not shown). After the trocar 40 and the connector 12
are connected, the sheath 300 is positioned over at least a portion
of the trocar 40, the connector 12, and at least a portion of the
flush tube portion 14 as shown in FIG. 11. The sheath 300 includes
an outer contour which is sufficiently smooth in both shape and
surface texture to pass through a subcutaneous tunnel 106 together
with the catheter 10 without substantial frictional resistance. The
sheath 300 masks any discontinuities at the interfaces between
outer surfaces of the trocar 40 and the connector 12 and between
outer surfaces of the connector 12 and the flush tube portion 14,
thereby providing the trocar/catheter assembly with an outer
contour that is more easily passed through a subcutaneous tunnel.
Preferably, the sheath 300 includes a leading tip portion 304 which
has an outer diameter substantially equal to the diameter of the
trocar 40 as shown, such that there is little or no discontinuity
formed between outer portions of the shaft 41 of the trocar 40 and
the adjacent leading tip portion 304 of the sheath 300.
[0055] Once the catheter 10 is tunneled as described above and the
connector 12, flush tube portion 14, and a distal portion of the
catheter tube 16 are severed from the remainder of the catheter
tube 16, the catheter 10 is ready for connection to a fluid
management device such as a dialysis machine. Preferably, the tip
of the multi-lumen catheter tube 16 protruding from the incision
104 (as shown in FIG. 9D) is attached to a selectively attachable
hub as described in co-pending application Ser. Nos. 09/769,052 and
10/086,033, which have been incorporated by reference above. As
shown in FIG. 3 of these applications, the cannulae 22a, 24a of the
selectively attachable hub 20 are inserted into the lumens at the
distal end of the multi-lumen catheter tube. As shown in FIG. 1 of
these applications, the hub 20 is then releasably connected to the
catheter tube by a compression sleeve 36 and compression cover 34.
The extension tubes 26,28 are then connected to a fluid management
device with connectors 30, 32. The incisions 100 and 104 are
dressed in an appropriate manner.
[0056] Preferably, the compression cover 34 and the compression
sleeve 36 are "preloaded" onto the trocar 40 by placing the
compression sleeve 36 and the compression cover 34 axially over the
tip 42 of the trocar 40. A protrusion, such as a small piece of
tape, can be wrapped around the trocar 40 between the tip 42 and
the preloaded to prevent compression sleeve 36 and the compression
cover 34 from inadvertently sliding off the trocar 40 before the
trocar 40 and the connector 12 are connected. Before the connector
12, flush tube portion 14, and a distal portion of the catheter
tube 16 are severed from the remainder of the catheter tube 16, the
compression cover 34 and the compression sleeve 36 are moved from
the trocar 40 onto the distal portion 16d of the catheter tube 16.
The compression cover 34 and the compression sleeve 36 are then in
a position to be fitted axially about the cannulae 22 and 24 so as
to create force to prevent inadvertent separation of the catheter
tube 12 from the hub 20.
[0057] The invention also includes a method of replacing a
multi-lumen catheter 10 which has been tunneled in a patient as
described above. First, the selectively attachable hub is removed
from the distal end of the catheter tube 16. Next, the catheter
tube 16 is withdrawn from the subcutaneous tunnel 106 from the
first end 102 of the tunnel 106. The proximal portions of the
catheter 10 are then withdrawn from the patient through an incision
100'. A replacement multi-lumen catheter 10' with an integrated
connector 12' is then tunneled in a patient by a procedure similar
to that described above, but using the same subcutaneous tunnel 106
formed in the patient for the original catheter 10 as shown in
FIGS. 9A-9D. Once the catheter tips 20', 21' of the replacement
catheter 10' are accurately positioned in the patient through
incision 100', a trocar 40 is inserted through the pre-formed
tunnel 106 such that the insertion tip 42 of the trocar 40
outwardly extends from the first end 102 of the tunnel 106 as shown
in FIG. 9A. A portion of the tunnel 130' may be re-dilated as
necessary as described above and as shown in FIGS. 9D and 10. A
sheath 300' may then be back-fitted over the insertion tip 42 and
the shaft 41 of the trocar 40. The connector 12' of the replacement
catheter 10' is connected to the tip 42 of the trocar 40 as shown
in FIG. 9B. The sheath 300' may then be positioned over portions of
the catheter 10' as shown in FIG. 11. The replacement catheter 10'
is then guided through the tunnel 106 with the trocar 40 until the
replacement catheter 10' is finally positioned in the patient as
shown in FIG. 9C. After severing the trocar 40, connector 12',
flush tube portion 14', and a distal portion of the catheter tube
16' from the remainder of the catheter tube 16' as shown in FIG.
9D, the replacement catheter 10' is connected to a fluid management
device as described above.
[0058] While this invention has been illustrated and described in
accordance with a preferred embodiment, it is recognized that
variations and changes may be made therein without departing from
the invention as set forth in the claims. Certain modifications and
improvements will occur to those skilled in the art upon a reading
of the forgoing description. For example, the connection means
between the integrated connector and the trocar may be configured
in any suitable manner which provides a secure connection. Also by
way of example, the process steps of forming a subcutaneous tunnel
and extending a trocar through the tunnel may occur simultaneously
rather than as discrete steps. It should be understood that all
such modifications are not contained herein for the sake of
conciseness and readability, but are properly within the scope of
the following claims.
* * * * *