U.S. patent application number 11/096257 was filed with the patent office on 2005-12-08 for catheter.
Invention is credited to Barzell, Winston E., Whitmore, Willet F. III, Wilson, Roger F..
Application Number | 20050273078 11/096257 |
Document ID | / |
Family ID | 32041826 |
Filed Date | 2005-12-08 |
United States Patent
Application |
20050273078 |
Kind Code |
A1 |
Whitmore, Willet F. III ; et
al. |
December 8, 2005 |
Catheter
Abstract
The present invention relates to a catheter that includes an
elongate body having distal and proximal ends, the elongate body
having at least one lumen therethrough, a distal portion of the
elongate body having a perimeter. First and second retention
members of the catheter are first and second retention members
selectively disposed in either an insertion state or a retention
state. In the insertion state, the first and second retention
members form a distal body defining a central axis, the central
axis being generally spaced apart from the perimeter of the distal
portion of the elongate body, the distal body and elongate body
insertable along a passageway of a mammal. In the retention state,
the first and second retention members are selectively disposed in
a spaced apart configuration to resist proximal movement of the
catheter along the passage of the mammal.
Inventors: |
Whitmore, Willet F. III;
(Longboat Key, FL) ; Barzell, Winston E.;
(Sarasota, FL) ; Wilson, Roger F.; (Sarasota,
FL) |
Correspondence
Address: |
STEPTOE & JOHNSON LLP
1330 CONNECTICUT AVENUE, N.W.
WASHINGTON
DC
20036
US
|
Family ID: |
32041826 |
Appl. No.: |
11/096257 |
Filed: |
April 1, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11096257 |
Apr 1, 2005 |
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PCT/US03/31723 |
Oct 2, 2003 |
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PCT/US03/31723 |
Oct 2, 2003 |
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10261662 |
Oct 2, 2002 |
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6929621 |
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Current U.S.
Class: |
604/544 ;
604/330 |
Current CPC
Class: |
A61M 25/0017 20130101;
A61M 25/04 20130101; A61M 2210/1085 20130101; A61M 27/008 20130101;
A61M 25/0069 20130101 |
Class at
Publication: |
604/544 ;
604/330 |
International
Class: |
A61F 005/44 |
Claims
1. A urinary drainage catheter composing: an elongate body
comprising: a distal portion; a proximal portion; and first and
second separate passages therealong; a distal balloon operatively
associated with the distal portion of the elongate body; and a
proximal balloon operatively associated with the proximal portion
of the elongate body, the distal and proximal balloons being in
hydraulic communication with one another via the second passage,
wherein an expansion of one of the balloons accompanies a
contraction of the other of the balloons.
2. The urinary drainage catheter of claim 1, wherein when the
distal portion of the elongate body is disposed in fluid
communication with a bladder of a mammal, the first passage allows
fluid to exit the bladder.
3. A sealed enclosure comprising the urinary drainage catheter of
claim 1, wherein the catheter is sterile and at least one of the
distal and proximal balloons comprises a fluid.
4. The sealed enclosure of claim 3, wherein the fluid is an aqueous
liquid.
5. A urinary drainage catheter comprising: an elongate member
comprising a distal portion, a proximal portion, and a urinary
drainage passage therealong; and a hydraulically actuated retention
mechanism operatively associated with the distal end of the
elongate member, the hydraulically actuated retention mechanism
comprising an actuation fluid and at least one retention member
rotatably associated with the distal portion of the elongate body,
the retention member (i) being free of the actuation fluid and (ii)
being hydraulically rotatable between an insertion state and a
retention state, the retention state being configured to resist
withdrawal of the catheter when the retention member is deployed in
the retention state within the bladder, the actuation fluid not
entering the retention member upon actuation to the retention
state.
6. The catheter of claim 5, wherein the catheter comprises a
proximal portion having at least one spatial marker indicative of
an orientation of the retention members.
7. A urinary drainage catheter for draining fluid from a bladder of
a catheterized mammal, comprising: an elongate body, comprising: a
distal portion; a proximal portion; and first and second separate
passages extending therealong; a distal enclosure operatively
associated with the distal portion of the elongate body and having
an insertion state and a retention state, the distal enclosure
being inflatable from the insertion state to the retention state
upon the introduction of an actuation fluid thereto and collapsible
from the retention state to the insertion state upon the exit of at
least some of the actuation fluid therefrom, wherein, when the
distal enclosure is in the retention state within the bladder, the
distal enclosure resists withdrawal of the distal portion of the
catheter along the urethra and the first passage facilitates
drainage of fluid from the bladder; and a fluid release mechanism
operatively associated with the proximal portion of the elongate
body, the distal enclosure being in hydraulic communication with
the fluid release mechanism via the second passage, wherein, when
the catheter is subjected to a traumatic withdrawing force directed
substantially along the urethra, the release mechanism operates to
allow actuation fluid to exit the second passage, whereupon the
distal enclosure collapses to the insertion state.
8. The urinary drainage catheter of claim 7, wherein the fluid
release mechanism is external to the urethra when the distal
enclosure is disposed within the bladder.
9. The urinary drainage catheter of claim 7, wherein the fluid
release mechanism comprises an expandable enclosure and operation
of the fluid release mechanism comprises introduction of fluid to
the expandable enclosure from the second passage.
10. The urinary drainage catheter of claim 9, wherein the
expandable enclosure comprises an expandable balloon formed of
elastic material.
11. The urinary drainage catheter of claim 10, wherein the distal
enclosure comprises an expandable balloon formed of elastic
material.
12. The urinary drainage catheter of claim 9, wherein the
expandable enclosure is an expandable sack formed of flexible
material.
13. The urinary drainage catheter of claim 7, wherein the fluid
release mechanism comprises a membrane and actuation of the fluid
release mechanism comprises at least one of an increase in an area
of the membrane and a rupture of the membrane.
14. The urinary drainage catheter of claim 13, wherein the membrane
has a thickness less than a thickness of the second passage
adjacent the membrane.
15. The urinary drainage catheter of claim 7, wherein the fluid
release mechanism comprises a relief valve.
16. The urinary drainage catheter of claim 15, wherein the valve is
a poppet relief valve.
17-34. (canceled)
35. A method for catheterizing a mammal comprising: providing a
catheter, the catheter comprising: an elongate body comprising: a
distal portion; a proximal portion; a distal enclosure operatively
associated with the distal portion of the elongate body; and a
proximal enclosure having at least one flexible wall, the proximal
enclosure being in fluidic communication with the distal enclosure;
passing the distal portion of the elongate body along at least a
portion of the urethra of the mammal, at least a portion of the
proximal enclosure remaining outside the urethra; introducing fluid
to the distal enclosure by applying pressure to the flexible wall
of the proximal enclosure whereupon fluid exits the proximal
enclosure and fluid enters and expands the distal enclosure within
the bladder of the mammal, wherein the expanded distal enclosure
resists withdrawal of the catheter along the urethra of the
mammal.
36. The method of claim 35, wherein the proximal enclosure
comprises at least one of a balloon and a flexible sack and
applying pressure to the flexible wall comprises squeezing the at
least one of the balloon and flexible sack.
37. The method of claim 35, wherein the catheter is a urinary
drainage catheter comprising at least one drainage passage and,
upon expansion of the distal enclosure, a distal opening of the at
least one drainage passage is disposed in fluidic communication
with the bladder.
38. The method of claim 35, wherein the step of providing a
catheter comprises: opening a sealed enclosure enclosing the
catheter, wherein, when the catheter is present within the sealed
enclosure, at least one of the proximal and distal enclosures
comprise an amount of liquid sufficient to expand the distal
enclosure by an amount sufficient to resist withdrawal of the
catheter from the urethra.
39-52. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of the U.S. National
Stage designation of co-pending International Patent Application
PCT/US03/31723 filed Oct. 2, 2003, which claims priority to U.S.
application Ser. No. 10/261,662 filed Oct. 2, 2002, and the entire
contents of these applications are expressly incorporated herein by
reference thereto.
FIELD OF THE INVENTION
[0002] The present invention relates to catheters and to retention
devices for removably retaining catheters within a body.
BACKGROUND OF THE INVENTION
[0003] Urinary catheters may be used to drain urine from the
bladder of a catheterized individual. One known catheter, the Foley
catheter, includes a balloon located near the tip of a tube sized
to pass through the urethra. Once the tip is within the bladder,
the balloon is filled with fluid to retain the tip in the bladder.
Because the balloon must be bulky in order to retain the catheter
tip, many patients experience discomfort when catheterized
particularly if the balloon contacts the trigone, which is very
sensitive. Moreover, the filled balloon may injure the patient if
traumatically withdrawn from the bladder.
[0004] There is a need for a catheter that may be disposed within a
bladder and retained without causing injury in the event of an
unintentional withdrawal. Additionally, there is a need for a
catheter that may be inserted and retained in a known orientation,
thereby reducing contact with the trigone of the catheterized
individual.
SUMMARY OF THE INVENTION
[0005] A first embodiment of the invention relates to a catheter,
comprising an elongate body having distal and proximal ends, the
elongate body having at least one lumen therethrough, a distal
portion of the elongate body having a perimeter; first and second
retention members, the first and second retention members being
selectively disposed in either an insertion state or a retention
state, wherein, in the insertion state, the first and second
retention members forming a distal body defining a central axis,
the central axis being generally spaced apart from the perimeter of
the distal portion of the elongate body, the distal body and
elongate body insertable along a passageway of a mammal; and in the
retention state, the first and second retention members are
selectively disposed in a spaced apart configuration to resist
proximal movement of the catheter along the passage of the mammal.
It should be understood that use of the word perimeter does not
constrain the elongate body to have a circular cross section.
[0006] The first and second retention members may each include
proximal and distal ends, the proximal ends rotatably associated
with the distal end of the elongate body. The distal ends of the
retention members may be free ends. The distal end of at least one
of the first and second retention members may rotate about a
rotation axis with respect to the distal end of the elongate body,
the rotation axis generally disposed at a proximal end of the
retention member. The distal end of each of the first and second
retention members may rotate about a respective rotation axis with
respect to the distal end of the elongate body, the rotation axes
being generally disposed at respective proximal ends of the
retention members.
[0007] A respective contour of the first and second retention
members may remain substantially constant upon movement from the
insertion state to the retention state.
[0008] The distal end of the catheter may include an opening to the
passage, wherein the central axis of the distal portion of the
elongate body intersects the opening. An inner surface of the
passage may be substantially concentric with an outer surface of
the elongate body.
[0009] When the first and second retention members are in the
retention state, a distance between a distal extent of the
retention members and an opening to the passage of the elongate
body may be less than about 3 times a maximum radial dimension of
the passage, wherein the distance is taken along the central axis
of the distal portion of the elongate body.
[0010] The first and second retention members may move proximally
upon moving from the insertion state to the retention state.
[0011] In the insertion position, a distal portion of the first
retention member may extend beyond the second retention member, the
distal portion of the first retention member having a substantially
unbroken surface. When viewed along the central axis of the
substantially distal body, the substantially unbroken surface of
the first retention member may obscure at least a portion of the
second retention member.
[0012] The catheter may further comprising a linkage, wherein the
first and second retention members are actuated via the linkage.
The linkage may comprise a linkage member, the linkage member being
rotatably associated with the first retention member and slidably
associated with the second retention member. The second retention
member may include a stop, which, in the retention state,
releasably accommodates an end of the linkage member thereby
inhibiting the retention members from returning to the insertion
position. The stop and the end of the linkage member are configured
to dissociate in response to a predetermined proximal force so that
the retention members may return to the insertion state.
[0013] The linkage may include first and second linkage members
having respective first and second ends, wherein the first end of
the first linkage member is rotatably associated with the first
retention member, the first end of the second linkage member is
rotatably associated with the second retention member, and the
respective second ends of the first and second linkage members are
rotatably associated with one another.
[0014] The linkage may comprise first and second linkage members,
the first and second linkage members rotatable with respect to one
another about a rotation axis, wherein, as the first and second
retention members move between the insertion state and the
retention state, the rotation axis translates substantially along
the central axis of the distal body. A distal extent of at least
one of the first and second retention members may be greater than a
distal extent of the linkage.
[0015] The linkage may include a linkage member having first and
second linkage member ends, a first end of the linkage member is
slidably and rotatably associated with the first retention member
and the second linkage member end is slidably and rotatably
associated with the second retention member.
[0016] The catheter may include a flexible enclosure, wherein
movement from the insertion state to the retention state is
actuated by expansion of the flexible enclosure.
[0017] A radial extent of at least one of the first and second
retention members may be at least about as great as a length of the
retention member.
[0018] The distal body may bifurcate upon moving from the insertion
state to the retention state.
[0019] The catheter may comprise a proximal portion having at least
one spatial marker indicative of an orientation of the first and
second retention members. At least one spatial marker may be
indicative of whether the retention members are aligned with a
coronal plane of a human catheterized with the catheter.
[0020] The passage may be a urethra. The mammal may be a human.
[0021] Another embodiment of the invention relates to a method for
catheterizing a mammal, comprising, providing a catheter comprising
an elongate body having distal and proximal ends, the elongate body
having at least one lumen therethrough, a distal portion of the
elongate body having a perimeter; first and second retention
members, the first and second retention members being selectively
disposed in either an insertion state or a retention state,
wherein, in the insertion state, the first and second retention
members forming a distal body defining a central axis, the central
axis being generally spaced apart from the perimeter of the distal
portion of the elongate body, the distal body and elongate body
insertable along a passageway of a mammal; and in the retention
state, the first and second retention members are selectively
disposed in a spaced apart configuration to resist proximal
movement of the catheter along the passage of the mammal; inserting
the catheter along a passageway of the mammal until first and
second retention members of the catheter enter a cavity of the
mammal; and moving the retention members from an insertion state to
a retention state, whereby the first and second retention members
are removably retained within the cavity.
[0022] Still another embodiment of the present invention relates to
a urethral catheter for catheterizing a bladder of a human having a
coronal plane. The urethral catheter comprises an elongate body
having a distal portion and a proximal portion, the elongate body
having a passage therealong; first and second retention members
movably associated with the distal portion of the elongate body,
the first and second retention member movable between an insertion
state and a retention state, wherein, in the retention state the
first and second retention members extend radially and
substantially along a single plane from the elongate body; and the
proximal portion of the elongate body includes at least one spatial
marker indicative of the whether the first and second retention
members are generally aligned with the coronal plane of the human
when the first and second retention members are in the bladder of
the human.
[0023] The first and second retention members may include
respective distal outer surfaces, and wherein the respective distal
outer surfaces define an angle of at least about 80 degrees with
respect to a central axis of the distal portion of the elongate
body.
[0024] Yet another embodiment of the present invention relates to a
urinary catheter retention device for insertion along a urethra
into a bladder of a human to releasably retain a passage of an
elongate body in fluid communication with the bladder, the
retention device comprising a base operably securable to an end of
the elongate body; first and second retention members movably
associated with the base and having respective free distal ends,
the free distal ends of the retention members movable between an
insertion state and a retention state, wherein, in the insertion
state, the first and second retention members cooperate to form a
body, the body being insertable along the urethra; and in the
retention state, the free distal ends are spaced apart from one
another to resist proximal movement of the elongate body along the
passage of the mammal.
[0025] Yet another embodiment of the invention relates to a
urethral catheter, comprising an elongate body, the elongate body
having at least one lumen therethrough; a first retention member,
the first retention having first and second ends and being
selectively disposed in either an insertion state or a retention
state, wherein, in the insertion state, the first and second ends
of the retention member are generally aligned with the elongate
body so that at least a portion of the catheter is insertable along
a urethra of a mammal; and in the retention state, the first and
second ends of the retention member are spaced apart from the
elongate body to resist proximal movement of the retention member
along the urethra of the mammal.
[0026] A generally medial portion of the retention member may be
rotatably associated with the catheter.
[0027] The catheter may include at least one tension member that
urges a generally medial portion of the retention member toward a
distal end of the catheter.
[0028] An axial distance between the generally medial portion of
the retention member and a distal end of the elongate body may
decrease by at least about one half upon moving from the insertion
state to the retention state.
[0029] Still another embodiment of the invention relates to a
urethral catheter, comprising an elongate body having a distal end
and a proximal end and at least one lumen therethrough; at least a
first retention member, the at least first retention member being
generally associated with the distal end of the elongate body and
selectively disposed in at least an insertion state and a retention
state, wherein, in the insertion state, the at least first
retention member is generally aligned with the elongate body and
insertable along a urethra of a mammal; and, in the retention
state, at least a portion of the at least first retention member is
radially spaced apart from the elongate body, wherein, upon the
application of a force of less than about 10 Newtons directed
generally proximally along the elongate body, the at least one
retention member resists proximal movement of the catheter along
the urethra and, upon the application of a force of less than about
25 Newtons directed generally proximally along the elongate body,
the at least one retention member returns to an insertion state to
permit withdrawal of the catheter along the urethra.
[0030] Upon the application of a force of less than about 20
Newtons directed generally proximally along the elongate body, the
at least one retention member may return to an insertion state to
permit withdrawal of the catheter along the urethra.
[0031] Upon the application of a force of less than about 15
Newtons directed generally proximally along the elongate body, the
at least one retention member may return to an insertion state to
permit withdrawal of the catheter along the urethra.
[0032] Another embodiment of the invention relates to a urinary
drainage catheter, comprising an elongate body comprising a distal
portion, a proximal portion, and first and second separate passages
therealong. The catheter may include a distal balloon operatively
associated with the distal portion of the elongate body, and,
optionally, a proximal balloon operatively associated with the
proximal portion of the elongate body, the distal and proximal
balloons preferably being in hydraulic communication with one
another, such as via the second passage, wherein an expansion of
one of the balloons accompanies a contraction of the other of the
balloons.
[0033] The distal portion of the elongate body may be disposed in
fluid communication with a bladder of a mammal, the first passage
allows fluid to exit the bladder.
[0034] The urinary drainage catheter may be provided within a
sealed enclosure comprising the urinary drainage catheter. The
catheter is sterile and at least one of the distal and proximal
balloons may comprise a fluid, such as an aqueous liquid.
[0035] Another embodiment of the present invention relates to a
urinary drainage catheter, comprising an elongate member comprising
a distal portion, a proximal portion, and a urinary drainage
passage therealong. The catheter may have a hydraulically actuated
retention mechanism operatively associated with the distal end of
the elongate member, the hydraulically actuated retention mechanism
preferably comprising an actuation fluid and at least one retention
member rotatably associated with the distal portion of the elongate
body. The retention member preferably (i) being free of the
actuation fluid and, optionally, (ii) being hydraulically rotatable
between an insertion state and a retention state, the retention
state being configured to resist withdrawal of the catheter when
the retention member is deployed in the retention state within the
bladder, the actuation fluid preferably not entering the retention
member upon actuation to the retention state.
[0036] Another embodiment of the invention relates to a urinary
drainage catheter for draining fluid from a bladder of a
catheterized mammal. The catheter may comprise an elongate body,
comprising a distal portion, a proximal portion, and first and
second separate passages extending therealong. The catheter may
include a distal enclosure operatively associated with the distal
portion of the elongate body and having an insertion state and a
retention state, the distal enclosure preferably being inflatable
from the insertion state to the retention state upon the
introduction of an actuation fluid thereto and collapsible from the
retention state to the insertion state upon the exit of at least
some of the actuation fluid therefrom. When the distal enclosure is
in the retention state within the bladder, the distal enclosure
preferably resists withdrawal of the distal portion of the catheter
along the urethra and the first passage facilitates drainage of
fluid from the bladder.
[0037] The catheter may include a fluid release mechanism
operatively associated with the proximal portion of the elongate
body, the distal enclosure being in hydraulic communication with
the fluid release mechanism via the second passage, wherein, when
the catheter is subjected to a traumatic withdrawing force directed
substantially along the urethra, the release mechanism operates to
allow actuation fluid to exit the second passage, whereupon the
distal enclosure collapses to the insertion state.
[0038] The fluid release mechanism may be external to the urethra
when the distal enclosure is disposed within the bladder. The fluid
release mechanism may comprise an expandable enclosure and
operation of the fluid release mechanism comprises introduction of
fluid to the expandable enclosure from the second passage. The
expandable enclosure may comprise an expandable balloon formed of
elastic material. The distal enclosure may comprise an expandable
balloon formed of elastic material. The expandable enclosure may be
an expandable sack formed of flexible material.
[0039] The fluid release mechanism may comprise a membrane and
actuation of the fluid release mechanism may comprise at least one
of an increase in an area of the membrane and a rupture of the
membrane. The membrane may have a thickness less than a thickness
of the second passage adjacent the membrane. The fluid release
mechanism may comprise a relief valve, such as a poppet relief
valve.
[0040] Another embodiment of the present invention relates to a
urinary drainage catheter for draining fluid from a bladder of a
mammal, comprising (i) an elongate body comprising a distal
portion, a proximal portion, and a first passage extending
therealong, the passage comprising a distal opening and a proximal
opening, and (ii) a distal enclosure operatively associated with
the distal portion of the elongate body and configurable in an
insertion state and a retention state. When the distal enclosure is
in the insertion state, at least the distal portion of the catheter
is preferably insertable along a urethra of the mammal at least
until at least a portion of the distal enclosure resides within the
bladder. When the distal enclosure is in the retention state and at
least partially resident within the bladder, the distal enclosure
preferably resists withdrawal of at least the distal portion of the
catheter along the urethra. The distal enclosure may expand from
the insertion state to the retention state upon the entry of fluid
thereto and contract from the retention state to the insertion
state upon the exit of fluid therefrom.
[0041] The catheter may include a proximal flexible fluid enclosure
(proximal enclosure) in fluidic communication with the distal
enclosure, wherein (a) at least a portion of at least one of the
proximal enclosure and the proximal opening of the passage
preferably resides external to the urethra when the distal
enclosure is in the retention state and resident within the
bladder, the passage providing drainage of fluid from the bladder,
and (b) exit of fluid from the proximal enclosure actuates
expansion of the distal enclosure from the insertion state to the
retention state and entry of fluid into the proximal enclosure may
accompany contraction of the distal enclosure from the retention
state to the insertion state.
[0042] The proximal enclosure may be formed of an elastic material.
The proximal enclosure may comprise a balloon. The proximal
enclosure may comprise a flexible sack.
[0043] A proximal portion of the elongate body may comprise an at
least partially circumferential collar, the collar movable
longitudinally along the elongate body, wherein, when the distal
enclosure is in the insertion state, the collar may be moved over
the proximal enclosure to allow the introduction of fluid to the
distal enclosure without substantial expansion of the proximal
enclosure.
[0044] The proximal enclosure, in the insertion state, may comprise
a maximum radial dimension at least 1.5 times greater, such as at
least 2.5 times greater, or at least 3.0 times greater than a
maximum radial dimension of a distal portion of the elongate
body.
[0045] The distal and proximal enclosures may be connected by a
second passage along which fluid may pass unobstructed between the
enclosures. The first and second passages may be are separate from
one another.
[0046] The distal enclosure may comprise at least one of an elastic
material and flexible material. The distal enclosure may comprise a
balloon.
[0047] The proximal enclosure may comprise a balloon.
[0048] The distal enclosure may comprise a flexible sack.
[0049] The distal enclosure may comprise an aqueous liquid and,
optionally, expansion and contraction of the distal enclosure
respectively comprise introduction and removal of the aqueous
liquid therefrom. The aqueous liquid may be saline solution.
[0050] When distal enclosure is in the retention state and resident
within the bladder, a withdrawing force of greater than 10 lbs
directed along the urethra and applied to the proximal portion of
the catheter may actuate collapse of the distal enclosure whereby
the catheter may withdraw from the urethra without substantial
injury to the mammal. The mammal may be a human.
[0051] The catheter may be provided within a sealed enclosure
comprising the urinary drainage catheter.
[0052] Another embodiment of the invention relates to a method for
catheterizing a mammal, comprising providing a catheter, the
catheter comprising an elongate body comprising a distal portion, a
proximal portion, a distal enclosure operatively associated with
the distal portion of the elongate body, and a proximal enclosure
having at least one flexible wall, the proximal enclosure being in
fluidic communication with the distal enclosure.
[0053] The distal portion of the elongate body may be passed along
at least a portion of the urethra of the mammal, at least a portion
of the proximal enclosure remaining outside the urethra. Fluid may
be introduced to the distal enclosure by applying pressure to the
flexible wall of the proximal enclosure whereupon fluid exits the
proximal enclosure and fluid enters and expands the distal
enclosure within the bladder of the mammal, wherein the expanded
distal enclosure resists withdrawal of the catheter along the
urethra of the mammal.
[0054] The proximal enclosure may comprise at least one of a
balloon and a flexible sack and applying pressure to the flexible
wall comprises squeezing the at least one of the balloon and
flexible sack.
[0055] The catheter may be a urinary drainage catheter comprising
at least one drainage passage and, upon expansion of the distal
enclosure, a distal opening of the at least one drainage passage
may be disposed in fluidic communication with the bladder.
[0056] The step of providing a catheter may comprise opening a
sealed enclosure enclosing the catheter, wherein, when the catheter
is present within the sealed enclosure, at least one of the
proximal and distal enclosures may comprise an amount of liquid
sufficient to expand the distal enclosure by an amount sufficient
to resist withdrawal of the catheter from the urethra
[0057] Another embodiment of the invention relates to a urinary
drainage catheter, comprising an elongate member comprising a
distal portion, a proximal portion, an actuation passage, and a
urinary drainage passage, wherein the actuation passage and urinary
drainage passage are separate from one another. The catheter may
include an hydraulically actuated retention mechanism operatively
associated with the distal portion of the elongate member, the
hydraulically actuated retention mechanism being deployable in an
insertion state and a retention state, the retention state being
configured to resist withdrawal of the catheter when the retention
mechanism is deployed within the bladder. The catheter may include
a proximal enclosure comprising at least one flexible wall and
being in fluidic communication via the actuation passage with the
hydraulically actuated retention mechanism, wherein exit of fluid
from the proximal reservoir actuates movement of the retention
mechanism from the insertion state to the retention state and entry
of fluid to the proximal enclosure accompanies movement of the
retention mechanism from the retention state to the insertion
state.
[0058] Another embodiment of the invention relates to an apparatus
for use in catheterizing a mammal, the apparatus comprising a
sealed enclosure enclosing at least a sterile urinary drainage
catheter, the catheter comprising an elongate body comprising a
distal portion, a proximal portion, and a passage therealong, a
hydraulically actuated retention mechanism operatively associated
with the distal portion of the elongate body, the retention
mechanism comprising a distal enclosure and having an insertion
state and a retention state, wherein, when the retention mechanism
is in the insertion state, at least the distal portion of the
elongate body is insertable along the urethra of the mammal, and
when the retention mechanism is in the retention state, the
retention mechanism resists withdrawal of at least the distal
portion of the elongate body along the urethra, a proximal
enclosure operatively associated with the proximal portion of the
elongate body, the proximal enclosure comprising at least one
flexible wall and being in fluid communication with the retention
mechanism, wherein at least one of the distal enclosure and the
proximal enclosure comprise a fluid, wherein exit of fluid from the
proximal enclosure and entry of fluid to the distal enclosure
actuate movement of the retention mechanism from the insertion
state to the retention state and entry of fluid to the proximal
enclosure and exit of fluid from the distal enclosure actuate
movement of the retention mechanism from the retention state to the
insertion state.
[0059] The proximal enclosure may comprise a liquid when the
catheter is enclosed within the sealed enclosure. The liquid may be
aqueous. The distal enclosure and the proximal enclosure may be a
closed system.
[0060] The retention mechanism may comprise a first retention
member, the first retention member preferably being rotatatable
with respect to the distal portion of the elongate body and wherein
movement of the retention mechanism from the insertion state to the
retention state comprises rotation of the first retention member
with respect to the distal portion of the elongate body.
[0061] The retention mechanism may comprise a second retention
member, the second retention member preferably being rotatatable
with respect to the distal portion of the elongate body and wherein
movement of the retention mechanism from the insertion state to the
retention state comprises rotation of the second retention member
with respect to the distal portion of the elongate body.
[0062] Another embodiment of the invention relates to a urinary
drainage catheter for catheterizing a mammal, comprising an
elongate body comprising a distal portion, a proximal portion, and
a urinary drainage passage therealong and an actuation passage
therealong, a hydraulically actuated retention mechanism
operatively associated with the distal portion of the elongate
body, the retention mechanism comprising a distal enclosure and
having an insertion state and a retention state, wherein when the
retention mechanism is in the insertion state, at least the distal
portion of the elongate body is insertable along the urethra of the
mammal, when the retention mechanism is in the retention state
within the bladder of the mammal, the retention mechanism resists
withdrawal of at least the distal portion of the elongate body
along the urethra, and movement of the retention mechanism from the
insertion state to the retention state is actuated by entry of
fluid to the distal enclosure and movement of the retention
mechanism from the retention state to the insertion state comprises
exit of fluid from the distal enclosure along the actuation
passage, and a fluid release mechanism in fluid communication with
the distal enclosure along the actuation passage, wherein, when the
retention mechanism is disposed in the retention state within the
bladder of the mammal, the fluid release mechanism is configured to
allow fluid to exit the distal enclosure upon the application of a
withdrawal force directed generally along the urethra, whereupon
the retention mechanism returns to the insertion state and the
catheter may withdraw along the urethra without substantial injury
to the mammal.
[0063] The fluid release mechanism may comprise a membrane and
actuation of the fluid release mechanism comprises at least one of
an increase in the area of the membrane and rupture of the
membrane. The membrane may have a thickness less than a thickness
of the actuation passage adjacent the membrane. The membrane may be
disposed external to the urethra when the retention mechanism is
within the bladder.
[0064] The fluid release mechanism may comprise a release valve.
The valve may be a poppet type relief valve.
[0065] The fluid release mechanism may comprise an expandable
enclosure, fluid preferably entering and expanding the expandable
enclosure upon actuation of the fluid release mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0066] The present invention is discussed below with reference to
the drawings, in which:
[0067] FIG. 1 shows a first embodiment of a catheter of the present
invention, the catheter being configured in an insertion state;
[0068] FIG. 2 shows the catheter of FIG. 1, the catheter being
configured in an retention state;
[0069] FIG. 3 shows a distal portion of the catheter of FIG. 1 in
an insertion state;
[0070] FIG. 4 shows a perspective of a distal portion of the
catheter of FIG. 1, the catheter being configured in a retention
state;
[0071] FIG. 5 shows a side view of the catheter of FIG. 4;
[0072] FIG. 6 shows an axial view of the catheter of FIG. 1, the
catheter being configured in a retention state in a bladder of a
human;
[0073] FIG. 7 shows a perspective view of the catheter of FIG. 1,
the catheter being configured in a second retention state;
[0074] FIG. 8 shows a perspective view of the catheter of FIG. 1,
the catheter being configured in a third retention state;
[0075] FIG. 9 shows a side view of distal portion of a second
embodiment of a catheter of the present invention, the catheter
being configured in an insertion state;
[0076] FIG. 10 shows a perspective view of a distal portion of the
catheter of FIG. 9, the catheter being configured in a retention
state;
[0077] FIG. 11 shows a cross-sectional side view of a distal
portion of a third embodiment of a catheter of the invention, the
catheter being configured in an insertion state;
[0078] FIG. 12 shows a cross-sectional side view of a distal
portion of the catheter of FIG. 11, the catheter being configured
in a retention state;
[0079] FIG. 13 shows a side view of a distal portion of a fourth
embodiment of a catheter of the invention, the catheter being
configured in an insertion state;
[0080] FIG. 14 shows a side view of a distal portion of the
catheter of FIG. 13, the catheter being configured in a retention
state;
[0081] FIG. 15 shows a perspective view of an elongate body of the
catheter of FIG. 13, retention members of the catheter not being
shown;
[0082] FIG. 16 shows a fifth embodiment of a catheter of the
present invention, the catheter being configured in an insertion
state;
[0083] FIG. 17 shows side view of a distal portion of the catheter
of FIG. 16, with the catheter being configured in a retention
state;
[0084] FIG. 18 shows an embodiment of a catheter retention device
of the present invention, the retention device being configured in
an insertion state;
[0085] FIG. 19 shows a side view of the catheter retention device
of FIG. 18, the catheter device being configured in a retention
state;
[0086] FIG. 20 shows a perspective view of the catheter retention
device of FIG. 18, the catheter being configured in a retention
state;
[0087] FIGS. 21 and 22 show a sixth embodiment of a catheter of the
present invention, with catheter being configured in an insertion
state;
[0088] FIGS. 23 and 24 show the catheter of FIGS. 21 and 22 being
configured in a retention state;
[0089] FIGS. 25 and 26 show a seventh embodiment of a catheter of
the invention, with the catheter being respectively configured in
an insertion state and a retention state; and
[0090] FIG. 27 shows an eighth embodiment of a catheter of the
invention, with the catheter being configured in an insertion
state;
[0091] FIGS. 28 and 29 show the catheter of FIG. 27 but being
configured in a retention state;
[0092] FIGS. 30A and 30B show an embodiment of a catheter retention
device of the invention, the catheter being respectively configured
in an insertion state and a retention state, a hydraulic actuation
device not being shown;
[0093] FIG. 31A shows a perspective view of the catheter retention
device of FIGS. 30A and 30B;
[0094] FIGS. 31B-31C show perspective views of the catheter
retention device of FIGS. 30A and 30B, a hydraulic actuation device
being shown; and
[0095] FIG. 32 shows a catheter comprising the catheter retention
device of FIGS. 30A to 31C.
DETAILED DESCRIPTION OF THE INVENTION
[0096] Referring to FIGS. 1 and 2, a catheter 20 of the present
invention is shown including an elongate body 22. Catheter 20 has a
proximal portion 24 and a distal portion 26. The catheter 20 may be
configured in at least either an insertion state or a retention
state, as shown in FIGS. 1 and 2, respectively. In the insertion
state, catheter 20 is insertable along a passageway or lumen of a
mammal until at least a portion of distal portion 26 resides within
a cavity of the mammal. In the insertion state, catheter 20 may be
removed along the passageway or lumen of a mammal without causing
injury thereto. Distal portion 26 preferably includes at least two
retention members 28, 30 which are movably associated with catheter
20. In the retention state shown in FIG. 2, at least a portion of
at least one of retention members 28, 30 is radially extended,
thereby resisting proximal movement of catheter 20 along the
passage. In a preferred embodiment, both retention members 28, 30
are radially extended in a retention state.
[0097] Catheter 20 has at least one retention member and may have
2, 3, 4 or even more retention members. A preferred embodiment of
catheter 20 has 2 retention members that retain the catheter in a
body cavity. Movement of retention members in accordance with the
present invention from the insertion state to the retention state
is an opening movement. In a two-retention member catheter, the
preferred retention member opening is a bifurcation. Movement of
retention members from the retention state to the insertion state
is a closing movement. For example, an operator may actuate a
closing movement of radially extending retention members 28, 30 of
catheter 20 so that the catheter returns to the insertion state
allowing the catheter to be withdrawn along a passageway without
causing injury to a catheterized mammal.
[0098] With respect to the anatomy of a mammal catheterized with
catheter 20, the term distal refers to a location that is farther
along the passageway from an exterior opening thereof than is
another location disposed closer to the exterior of the passageway.
For example, catheter 20 may be inserted along the urethra of a
human so that retention members 28, 30 are positioned within the
bladder of the human. Upon such an insertion, the bladder and
retention members 28, 30 are distal to the external opening of the
urethra. With respect to catheter 20, the term distal refers to
locations closer to a distal end 36 thereof than to proximal
portion 24.
[0099] Referring to FIG. 3, first and second retention members 28,
30 cooperate in the insertion state to form a distal body 34, which
is shaped to allow catheter 20 to be inserted along a passageway.
Distal body 34 may be substantially cylindrical, prolate, conical,
wedged, spherical, or have another configuration suitable to allow
the catheter to pass along the respective passageway. During the
insertion, the distal body 34 is distal to elongate body 22. Thus,
insertion of catheter 20 along a passage may also be facilitated by
the shape of distal end 36 of distal body 34. Respective retention
member distal ends 33, 35 preferably cooperate to form a single
substantially blunt surface at distal end 36. Other than distal
body 34, distal portion 26 of catheter 20 is preferably free of
distally extending projections, such as those that may engage or
interfere with portions of the passage as the catheter is inserted
therealong.
[0100] Distal body 34 defines a distal body axis a.sub.1, which is
central to a perimeter p.sub.1 of distal body 34, as shown in FIG.
3. A distal portion 27 of elongate body 22 defines a distal portion
axis a.sub.2, which is central to a perimeter p.sub.2 a of distal
portion 27 of elongate body 22. Distal body axis a.sub.1 is
preferably spaced apart from perimeter p.sub.2. In a preferred
embodiment, distal body axis a.sub.1 is central to perimeter
p.sub.2. Distal body axis a.sub.1 may be aligned with distal
portion axis a.sub.2 of distal portion 27 of elongate body 22. It
should be understood that, because elongate body 22 may be formed
of a flexible material, the relative alignment of distal body axis
a.sub.1 and distal portion axis a.sub.2 may vary. When, however,
catheter 20 is straightened so that perimeters p.sub.1, p.sub.2 are
parallel to one another, axes a.sub.1, a.sub.2 are preferably
alignable, as seen in FIGS. 1 and 3.
[0101] Referring to FIGS. 4-6, the radial extent of first and
second retention members 28, 30 increases upon moving from the
insertion state to the retention state so that catheter 20 resists
proximal movement along a passage when the retention members are
within a cavity. Thus, distal retention member ends 33, 35 are
spaced apart and retention members 28, 30 no longer cooperate to
form distal body 34. In the retention state, a respective radial
extent d.sub.1 of at least one and preferably both retention
members 28, 30 is preferably at least about as great and more
preferably greater than a respective retention member length
l.sub.1. Radial extent d.sub.1 is the distance from the maximum
radial extent of an end of a retention member to central axis
a.sub.2. For example, the radial extent d.sub.1 of a retention
member may be at least about 90%, at least about 100%, or at least
about 110% of the length l.sub.1 of the retention member. Of
course, the radial extent of retention members of catheters of the
invention may be different, for example, if either of retention
members 28, 30 is rotated farther out from central axis a.sub.2.
Similarly, the lengths of retention members may be different.
[0102] The opening motion of the retention members 28, 30
preferably does not involve bending of respective medial portions
53, 55 of the retention members. Retention members 28, 30
preferably do not compress, such as along axis a.sub.1, upon
opening. Thus, the respective lengths of retention members 28, 30
are preferably substantially the same in both the insertion and
retention states.
[0103] A width w.sub.1 of retention members 28, 30 may be
substantially constant as a function of radial distance along the
length thereof. Alternatively, w.sub.1 may vary as a function of
distance from central axis a.sub.1. For example, a width of the
retention members may initially increase with radial distance
perhaps decreasing toward distal ends of the retention members so
that they have a shape that is petaloid, prolate, spheroid, or
similar. In the insertion state, the distal body formed by the
cooperation of such petaloid or prolate retention members may form
a waist or narrower region that is disposed proximal to a distal
end of the distal body. Other exemplary retention members have a
maximum width at proximal ends thereof and taper to a smaller width
at their distal ends.
[0104] A lumen 32 runs substantially along an interior length of
elongate body 22. When retention members 28, 30 are within a cavity
of a mammal, lumen 32 may be in fluid communication with the cavity
so that fluid may pass along the lumen between an exterior of the
mammal and the cavity. Preferably, fluid may exit the cavity via
lumen 32. A distal opening 38, which is preferably disposed at a
distal end 40 of elongate body 22, allows fluid to enter lumen 32.
For example, urine may exit a bladder of a catheterized mammal.
Proximal portion 24, which preferably remains at least partially
exposed upon catheterization with catheter 20, may be configured to
operatively connect with a drainage system or reservoir so that
fluid exiting the cavity may be disposed of or collected.
[0105] In the retention state, as seen in FIG. 5, a location of a
maximum distal extent of catheter 20 is preferably spaced apart
from axis a.sub.2 of the distal portion 27 of elongate body 22. A
radial distance between axis a.sub.2 and a portion defining a
maximum distal extent of the catheter may be at least twice a
maximum radial dimension of distal portion 27, such as at least
three or four times a diameter thereof. For example, a location of
maximum distal extent may be determined by respective distal ends
33, 35 of retention members 28, 30.
[0106] In the retention state, a distance d.sub.2 between distal
opening 38 and the maximum distal extent of catheter 20 is
preferably less than about 6 times, such as less than about 4 times
greater than the diameter d.sub.3 of distal portion 27 of elongate
body 22.
[0107] Distal opening 38 is preferably intersected by central axis
a.sub.2 of distal portion 27 of elongate body 22. Lumen 32 is
preferably concentric with elongate body 22. Lumen 32 may be the
only lumen passing along the length of the elongate body 22 between
the proximal 24 and distal 27 portions thereof. Therefore, the
capacity of the lumen 32 to conduct fluid is increased as compared
to a catheter having more than one lumen extending therealong.
[0108] Referring back to FIG. 4 and also to FIGS. 7 and 8,
respective distal ends 33, 35 of retention members 28, 30 rotate
with respect to elongate body 22 during movement between the
insertion and retention states. The distal ends 33, 35 preferably
rotate about respective rotation axes a.sub.3, a.sub.4, which axes
are preferably disposed at or adjacent respective proximal ends 37,
39 of retention members 28, 30. The retention members 28, 30
preferably open and close without bending along their lengths other
than any bending that may occur at or adjacent their proximal ends
37, 39. The rotatable association is via respective first and
second flexible connections 42, 44, which are preferably capable of
repeated bending without damage. The rotatable association of
retention members 28, 30 may also be accomplished by other
elements, such as pivots or hinges, by which at least one of
retention members 28, 30 may rotate with respect to catheter 20.
The flexible connections may be secured to catheter 20 using, for
example, at least one of friction, adhesives or ultrasonic welding.
Alternatively, retention members 28, 30 may be integral with distal
portion 27 of elongate body 22 of catheter 20.
[0109] Referring back to FIG. 5, respective proximal outer surfaces
58, 60 of retention members 28, 30 define, in the retention state,
an angle .theta..sub.1 of at least about 65 degrees, preferably at
least about 75 degrees, and most preferably at least about 80
degrees with respect to central axis .theta..sub.1 of distal body
34. Angle .theta..sub.1 is preferably less than about 115 degrees,
such as less than about 100 degrees or even less than about 95
degrees. Thus, with angle .theta..sub.1 at least about 75 degrees,
the retention members 28, 30 proximally extending and elongate body
22 may be said to define a "T-shape." One or both of portions 58,
60 may be distal to portions 37, 39 when the retention members are
in a retention state.
[0110] As best seen in FIGS. 6 and 7, the first and second
retention members 28, 30 may be actuated by a linkage 46. Upon a
first actuation motion of linkage 46, retention members 28, 30 move
from the insertion state to the retention state. Upon a second
actuation motion of linkage 46, retention members 28, 30 move from
the retention state to the insertion state.
[0111] Linkage 46 includes first and second linkage portions 52, 54
that rotate with respect to one another about a rotation axis
a.sub.5 at a rotatable connection 56, as seen in FIG. 6. Linkage
portions 52, 54 may be of unitary construction or may be formed of
separate portions connected by rotatable connection 56. Linkage
portions 52, 54 have a length l.sub.2, which is less than about
75%, such as less than about 60%, as long as length l.sub.1 of
retention members 28, 30.
[0112] Upon actuation of linkage 46, rotatable connection 56
translates generally linearly along central axis a.sub.1 of distal
body 34. Rotatable connection 56 may be a pivot having a pivot pin
58 centered upon rotation axis a.sub.5. A rotatable connection may
instead be formed of a flexible connection that allows the first
and second linkage portions 52, 54 to rotate with respect to one
another. A rotatable connection may also be a connection in which a
portion of one of the linkage members rotates within a portion of
the other linkage member. A socket joint in which a convex portion,
such as a ball-like portion, of one linkage member rotates within a
concave portion, such as a socket, of the other linkage member is
an example of such a connection.
[0113] First and second linkage portions 52, 54 are rotatably
associated with first and second retention members 28, 30,
respectively. Upon actuation of linkage 46, linkage portion 52
rotates with respect to retention member 28 about a rotation axis
a.sub.6 via a rotatable connection 62; linkage portion 54 rotates
with respect to retention member 30 about a rotation axis a.sub.7
via a rotatable connection 64. Thus, one embodiment of the linkage
may include 3 rotatable connections. Rotatable connections 62, 64
are pivots having respective pivot pins 66, 68 centered about
respective rotation axes a.sub.6, a.sub.7. Alternatively, linkage
portions 52, 54 may be rotatably associated with respective
retention members 28, 30 via flexible connections or socket
joints.
[0114] In the retention state, a radial distance d.sub.4 between
one and preferably both of rotatable connections 62, 64 and central
axis a.sub.1 of distal body 34 is preferably less than the
respective radial extent d.sub.1 of the one or both retention
members 28, 30. Preferably, distance d.sub.4 is less than about 80%
such as less than about 70% of d.sub.1. In the insertion state, a
distal extent of one and preferably both retention members 28, 30
is preferably greater than a distal extent of rotatable connection
56 of linkage 46. Therefore, when catheter 20 is viewed along
central axis a.sub.1 in the insertion state, retention members 28,
30 preferably enclose linkage 46 so that when catheter 20 is
inserted, linkage portions 52, 54 do not contact the passage.
[0115] In the insertion state, rotation axis a.sub.5 of rotatable
connection 56 is preferably distal to rotation axes a.sub.6,
a.sub.7 of respective rotatable connections 62, 64. In the
retention state, rotation axis a.sub.5 may be proximal to rotation
axes a.sub.6, a.sub.7. Preferably, a line between one of rotation
axes a.sub.6, a.sub.7 and rotation axis a.sub.5 defines an angle
.theta..sub.2 of at least about 5 degrees and more preferably at
least about 10 degrees with respect to a line normal to central
axis a.sub.2 of distal portion 27. Angle .theta..sub.2 is
preferably less than about 25 degrees, such as less than about 18
degrees. In some embodiments, rotation axis a.sub.5 may be distal
to rotation axes a.sub.6, a.sub.7 in the retention state.
[0116] In use, an operator may insert catheter 20 along a passage,
such as a urethra, until retention members 28, 30 are disposed
within a body cavity, such as a bladder. Proximal catheter portion
24 may include one or more radially extending elements 76, which
are seen in FIGS. 1 and 2 and prevent over-insertion of catheter
20. Once retention members 28, 30 are disposed within a body
cavity, the operator actuates linkage 46 to open the retention
members to the retention state. Catheter 20 includes an actuation
member 74, which is preferably configured to communicate tension to
linkage 46 to actuate the opening motion of retention members 28,
30. In use, actuation member 74 may extend from linkage 46
generally along lumen 32 to proximal portion 24 of catheter 20. An
operator may actuate linkage 46 by, for example, applying tension
to a proximal portion of actuation member 74. Actuation member 74
may be a filament, fine wire, or other string-like element that may
communicate, such as by communicating tension, with linkage 46 for
actuation thereof.
[0117] Actuation member 74 may extend along the same lumen used to
provide drainage of fluid. Alternatively, the elongate body may be
provided with a second, preferably separate lumen. Actuation member
74 may extend along this second lumen. In any event, it is
preferred that a proximal portion of actuation member 74 be
accessible to an operator inserting catheter 20 along a urethra of
a patient.
[0118] In addition to, or as an alternative to, actuating an
opening movement of the retention members, the actuation member 74
may be configured to resist a closing motion of the retention
members absent the application of a traumatic withdrawal force to
the retained catheter. Preferably, once the retention members have
been moved to the retention state in a bladder, actuation member 74
is secured so that a closing motion of the retention members
applies increasing tension to the actuation member. For example,
referring to FIG. 8, a distal portion of actuation member 74 is
secured to linkage 46 adjacent axis a.sub.5 thereof. Upon
deployment of the retention members, a proximal portion of the
actuation member may be secured, such as to a proximal portion of
the elongate body. Axis a.sub.5 is disposed distal to axes a.sub.6
and a.sub.7 in the retention state. A closing motion of the
retention members urges linkage 46 distally at axis a.sub.5 thus
applying tension to the secured actuation member 74. At least one
of the linkage and retention members may include a mechanical stop
configured to maintain axis a.sub.5 distally to axes a.sub.6,
a.sub.7 in the retention state.
[0119] The tension applied to actuation member 74 by linkage 46
resists movement of the linkage and, therefore, the closing motion
of the retention members. However, upon the application of a
traumatic withdrawing force, the retention members overcome the
resistance offered by the actuation member and return to the
insertion state allowing injury-free withdrawal.
[0120] In one embodiment, the actuation member is elastically
secured, preferably to linkage 46 and a proximal portion of the
elongate body. For example, the actuation member may itself be
elastic. A closing motion of the retention members may stretch the
actuation member. A sufficient withdrawal force overcomes the
elasticity allowing the retention members to return to the
insertion state. Alternatively, or in addition to an elastically
secured actuation member, the elongate body may have a degree of
compressibility. In this case, a closing motion of the retention
members applies tension to the secured actuation member. The
tension causes compression of at least a portion of the elongate
body. Once the elongate body has compressed sufficiently, linkage
46 is provided with enough freedom of movement to allow the
retention members to return to the insertion state.
[0121] When retention members 28, 30 are inserted into a body
cavity and moved to the retention state, the retention members
preferably resist proximal motion of catheter 20 to thereby
maintain fluid communication between passage 38 and the body
cavity. In use, however, sudden traumatic forces may be applied to
an inserted catheter by, for example, a disoriented patient. A
traumatic force is a force sufficient to cause injury to the
catheterized individual were the catheter not to return to an
insertion state. Therefore, retention members 28, 30 of catheter 20
are configured to return to the insertion state upon the
application of such a traumatic force so that catheter 20 may
withdraw without causing injury.
[0122] To achieve both ordinary retention and injury-free traumatic
withdrawal of catheter 20, retention members 28, 30 of catheter 20
preferably resist return to the insertion state with an initial
degree of resistance and a later degree of resistance. The initial
degree of resistance is greater than the later degree of resistance
and may be provided by the configuration of linkage 46. For
example, upon the application of a force proximally directed along
elongate body 22 when catheter 20 is in the retention state,
linkage 46 resists the return of retention members 28, 30 to the
insertion state when rotation axis a.sub.5 of rotatable connection
56 is proximal to rotation axes a.sub.6, a.sub.7 of respective
rotatable connections 62, 64.
[0123] When a traumatic force applied proximally along elongate
body 22 overcomes the initial degree of resistance, the
configuration of the linkage 46 changes, thereby allowing the
retention members 28, 30 to return to an insertion state with a
minimum of resistance. By return to an insertion state, it is meant
that the catheter returns to a state in which the distal portion of
the catheter may pass along a passageway without injury to a
catheterized mammal. For example, linkage portions 52, 54 may be
configured to disengage one another at rotatable connection 56.
Such disengagement may be provided by, for example, a
ball-and-socket joint in which the ball-like portion is released
from the socket upon the application of a traumatic force.
Disengagement may also take place at one of rotatable connections
62, 64. As an alternative to disengagement, one or both of linkage
members 52, 54 may be configured to bend or fold up in response to
a traumatic proximal force so that retention members 28, 30 may
close with a minimum of resistance.
[0124] In the retention state, retention members 28, 30 preferably
resist proximal movement of catheter 20 for proximally applied
forces of less than about 12 Newtons, such as less than about 10
Newtons, for example, less than about 8 Newtons, applied to
elongate body 22, but return to an insertion state to permit injury
free withdrawal of catheter 20 upon application of a force less
than about 25 Newtons, such as a force of less than about 20
Newtons, for example, a force of less than about 15 Newtons. For
example, a catheter that resists proximal movement of for
proximally, applied forces of less than about 12. Newtons but
returns to an insertion state upon application of a force of less
than about 20 Newtons might remain retained upon application of an
11 Newton force but return to the insertion state upon application
of a force of 18 Newtons. Of course, such a catheter would also
return to the insertion state upon application of forces greater
than 18 Newtons. It is understood that a force of about 4.4 Newtons
is equivalent to about 1 pound of force.
[0125] In its application or use, a catheter of the invention is
preferably inserted so that when the one or more retention members
extend radially within a bladder, respective proximal outer
surfaces of the one or more extended retention members contact a
surface of the bladder thereby inhibiting proximal movement of the
catheter. For example, as seen in FIG. 5, retention members 28, 30
include proximal outer surfaces 58, 60 that may contact the
bladder. Retention members of preferred catheters are preferably
configured to minimize contact with the trigone of the bladder. As
understood in the art, the trigone is a generally triangular shaped
region of the interior of the bladder. The trigone is bounded by
respective lines extending from the urethral orifice at the bladder
neck to the urethral orifices and a line extending between the
ureteral orifices.
[0126] To allow catheter retention with minimal contact with the
trigone, catheters of the invention in the retention state
preferably have a first radial extent that is greater than a second
radial extent of the catheter. For example, retention members 28,
30 of catheter 20 may be retained within a bladder with only
minimal or no contact with the trigone. Referring to FIG. 6, a
maximum radial dimension d.sub.5 of retention members 28, 30 is
greater than a minimum radial dimension d.sub.6 of the distal
portion 26 of the catheter 20. For example, the ratio of the
dimensions d.sub.5 and d.sub.6 may be at least about 3, such as at
least about 4, and for example at least about 5. The minimum radial
extent d.sub.6 may be substantially equal to a diameter d.sub.3 of
the distal portion 27. When retention members 28, 30 are disposed
generally parallel to the coronal plane of a catheterized
individual, they essentially avoid contact with the trigone thereby
minimizing discomfort to the catheterized individual.
[0127] Catheter 20 may include spatial markers indicative of the
spatial orientation of retention members 28, 30, when catheter 20
is in a relaxed, substantially untwisted state. The spatial markers
allow an operator to determine the orientation of retention members
28, 30 even when these are present within a body cavity. The
spatial markers may be the radially extending elements 76, which,
when catheter 20 is in the relaxed state, may lie in the same plane
as retention members 28, 30, when in the retention state. Indicia,
such as surface markings, on proximal portion 24 may also serve as
spatial markers. Spatial markers indicia of the spatial orientation
of retention members and/or distal portions of catheters of the
present invention may be used with any catheter in accordance with
the present invention.
[0128] During insertion, torsional forces may cause catheter 20 to
depart briefly from a relaxed orientation such that distal portion
26 twists with respect to the spatial markers. However, when
catheter 20 is inserted according to catheterization procedures
generally practiced by one in the art, such as with proper
lubrication, catheter 20 will return substantially to the relaxed
orientation so that the orientation of the spatial markers are
indicative of the orientation of retention members 28, 30. Thus,
the operator may insert catheter 20, determine whether retention
members 28, 30 are disposed along a desired orientation, such as
the coronal plane, and extend the retention members. Markers 76 may
be releasably fixed with respect to retention members 28, 30 to
maintain the desired orientation of the retention members 28, 30.
For example, proximal portion 24 and/or markers 76 may be taped to
the anterior surface of the thigh or to the lower abdomen.
[0129] Referring to FIGS. 9 and 10, an exemplary embodiment
includes a distal portion 126 of a catheter 120 including first and
second retention members 128, 130. In the insertion state, as seen
in FIG. 9, retention members 128, 130 cooperate to form a distal
body 136 having a central axis a.sub.11. A distal extent of a
distal end 135 of second retention member 130 is greater than a
distal extent of a distal end 133 of first retention member 128.
When catheter 120 is inserted along a passage, distal end 135
presents a substantially unbroken surface to the passage as
retention members 128, 130 progress therealong. Because distal end
135 presents a substantially unbroken surface, forces directed
generally against distal end 135 do not tend to urge retention
members 128, 130 apart. The distal end 135 preferably obscures or
encloses at least a portion of retention member 128 when catheter
120 is viewed along central axis a.sub.11.
[0130] Retention members 128, 130 of catheter 120 function in
accordance with retention members of catheters of the present
invention. Thus, in the retention state, as seen in FIG. 10, distal
ends 133, 135 are spaced apart so that catheter 120 resists
proximal motion when retention members 128, 130 are disposed within
a body cavity. Fluid may pass along a lumen 132 of an elongate body
122 of catheter 120. Lumen 132 includes a distal opening 138, which
is in fluid contact with the body cavity when the retention members
128, 130 are disposed therein. A proximal portion (not shown) of
catheter 120 may be identical to proximal portion 24 of catheter 20
so that fluid may be collected or disposed of. Catheter 120 may
include spatial markers so that the retention state orientation of
retention members 128, 130 may be determined.
[0131] Retention members 128, 130 may be actuated in accordance
with catheters of the present invention. Thus, for example, a
linkage 146 of catheter 120 includes a rotatable connection 156 at
which first and second linkage portions 152, 154 rotate via respect
to one another. Linkage portions 152, 154 are preferably rotatably
connected with respective retention members 128, 130. Rotatable
connections of linkage 146 may be pivots, flexible connections,
ball-and-socket joints, or other connection about which two
portions may rotate relative to one another.
[0132] Referring to FIGS. 11 and 12, a distal portion 226 of a
catheter 220 includes first and second retention members 228, 230,
which rotate with respect to catheter 220 about respective axes
a.sub.23, a.sub.24. The rotatable association of the retention
members 228, 230 is accomplished by respective first and second
pivots 242, 244 but may also be accomplished by other rotatable
elements such as flexible connections between the retention members
and elongate body 222.
[0133] In an insertion state, as seen in FIG. 11, retention members
228, 230 cooperate to form a distal body 234 having a central axis
a.sub.21. Upon a first actuation motion, the retention members 228,
230 move from the insertion state to a retention state, as seen in
FIG. 12, in which the retention members are spaced apart so that
catheter 220 resists proximal movement when the retention members
are disposed in a body cavity. Upon a second actuation motion, the
retention members 228, 230 move from the retention state to the
insertion state. An actuation motion of a linkage 246 actuates
movement of retention members 228, 230 from the insertion state to
the retention state. Linkage 246 includes a linkage member 252
having first and second ends 249, 251.
[0134] The opening motion of retention members 228, 230 may be
actuated by applying tension to linkage member 252, such as by a
tension member 274. The tension member 274 preferably extends from
an attachment point 261 of the linkage member 252 to the proximal
portion of catheter 220. Upon actuation of linkage 246, first
linkage member end 249 rotates with respect to retention member 228
about a rotation axis a.sub.26 via a rotatable connection, which is
a pivot 262. The rotatable connection may also be, for example, a
flexible connection or a ball-and-socket connection.
[0135] Second retention member 230 includes a captivating channel
263 having first and second ends 265, 267. Upon actuation of
linkage 246, second linkage member end 251 slides generally along
captivating channel 263 from the first end 265 to the second end
267 thereof. When a radial extent of first and second retention
members 228, 230 is sufficient to resist proximal movement along
the passage, second linkage member end 251 releasably associates
with a stop 269, as shown in FIG. 11, disposed at the second
captivating channel end 267. Stop 269 is preferably at least
partially complementary in shape to second linkage member end 251.
The releasable association of second linkage member end 251 and
stop 269 resists a return motion of second linkage member end 252
from second captivating channel end 267 to first captivating end
265. Thus, in the absence of a traumatic proximal force, catheter
220 remains inserted with the retention members disposed in the
body cavity. Linkage member 252 and stop 269 may be characterized
as a detent.
[0136] To reduce unintentional dissociation of second linkage
member end 251 and stop 269, it is desirable that a compressive
force be exerted generally along linkage member 252 and stop 269.
The compressive force preferably increases friction between second
linkage member end 251 and stop 269. Thus, absent a traumatic
proximal force, second linkage member end 252 and stop 269 remain
associated. To achieve the compression, one or both of first and
second members 228, 230 may be urged to rotate about respective
axes a.sub.3, a.sub.4 as if to return to the insertion state,
thereby providing compression along second linkage member 252
between rotatable connection 262 and stop 269.
[0137] One or both of the retention members 28, 30 may be urged to
rotate toward the insertion state via the expansion of a compressed
resilient material or the contraction of a resilient material under
tension. For example, a distance d.sub.24 between rotational axis
a.sub.24 and a shoulder 270 of second retention member 230 is
greater than a distance d.sub.25 between rotational axis a.sub.24
and a proximal end 272 of second retention member 230. A distal end
240 of catheter 220 has a shoulder 274 comprising a resilient
material such as surgical rubber. As second retention member
rotates into the fully opened state, retention member shoulder 270
contacts catheter shoulder 274, thereby compressing shoulder 274.
The compression urges second retention member 230 to rotate in the
opposite direction about axis a.sub.24, thereby applying the
compressive force along second linkage member 252.
[0138] Application of a traumatic proximal force to catheter 220
causes retention member 228, 230 to return to the insertion state
thereby allowing catheter 220 to withdraw along the passage without
causing injury. Linkage member 252 may be constructed of resilient
material, which allows a bending motion of the linkage member upon
the application of a traumatic force. The bending motion causes
second linkage member end 251 and stop 269 to disengage. Linkage
member 252 may include a portion having a lowered resistance to
bending than other portions of the linkage member. Upon the
application of a traumatic force, the linkage member 252
preferentially bends at the portion with lowered bending
resistance. For example, linkage member 252 has a lowered
resistance to bending about a notch 278 than about other portions
of the linkage member.
[0139] Retention members 228, 230 may be returned to the insertion
state by intentionally disengaging second linkage member end 251
and stop 269. Such dissociation may be accomplished by exerting a
distally directed force against a portion of linkage member 252.
For example, an operator may insert a stylet or trocar generally
along the lumen 232 of catheter 220 and press against a midpoint
280 of linkage member 252, which may bend about a shoulder 282
adjacent captivating channel 263. Once the second linkage member
end 251 and stop 269 dissociate, retention members 228, 230 return
readily to the insertion state allowing the withdrawal of catheter
220.
[0140] Referring to FIGS. 13 and 14, a catheter 320 includes an
enclosure 321 and at least first and second retention members 328,
330. Retention members 328, 330 may be disposed in at least an
insertion state, as seen in FIG. 13, and a retention state, as seen
in FIG. 14. An opening motion of retention members 328, 330 is
preferably actuated by expansion of the enclosure 321, such as with
a fluid, such as a gas or liquid. Saline is a preferred fluid. A
closing motion of retention members 328, 330 is preferably actuated
by release of fluid from enclosure 321. Upon opening or closing,
retention members 328, 330 preferably rotate about rotation axes
a.sub.33, a.sub.34 with respect to catheter 320. Rotatable
association of retention members 328, 330 and catheter 320 may be
accomplished by, for example, pivots, hinges, flexible connections,
socket joints or other rotatable connection. The actuation of
retention members using a fluid may be referred to as hydraulic
actuation.
[0141] Referring also to FIG. 15, a proximal portion 324 of
catheter 320 includes a port 323 in fluid communication with a
lumen 333, which extends from port 323 to enclosure 321. Port 323
may be any element that allows the introduction of fluid into lumen
333. For example, the fitting may be compatible with a syringe so
that the syringe may be used to inject fluid along lumen 333. Fluid
entering lumen 333 expands enclosure 321, which expansion exerts a
preferably radial force upon retention members 328, 330 to extend
them radially. For example, a radial force may be generated when
the expanding enclosure contacts surfaces 327, 329 of retention
members 328, 330. Once retention members are radially extended
within a cavity of a mammal, proximal motion of catheter 320 is
thereby inhibited. Proximal portion 324 of catheter 320 may include
spatial markers so that retention members 328, 330 may be opened in
a known orientation within the cavity, such as in the coronal plane
within the bladder of a human.
[0142] Enclosure 321 may be expanded upon injection of less than
about 2 cubic centimeters of liquid therein. Enclosure 321
preferably has a maximum dimension d.sub.8 that is less than about
3 times, such as less than about 2 times a maximum radial dimension
d.sub.43 of a distal portion 327 of catheter 320. Therefore,
contact of enclosure 321 with inner surfaces of the cavity
preferably has essentially no tendency to retain catheter 320
therein. Rather, resistance to proximal motion of catheter 320 is
preferably due essentially only to radially expanded retention
members. For example, proximal surfaces 358, 360 of retention
members 328, 330 may contact the inner surface of the cavity.
[0143] Catheter 320 includes a second lumen 332 running
substantially along an elongate body 322 of the catheter. Lumen 332
may operate in accordance with lumen 32 of catheter 20, such as to
allow urine to exit a bladder of a catheterized human. A distal end
340 of catheter 320 includes an opening 338 to lumen 332. Retention
members 328, 330 may also include passages to allow fluid to
communicate between the cavity and lumen 332.
[0144] An operator may release fluid from enclosure 321, such as by
using a syringe to withdraw fluid from lumen 333 or simply by
breaking a seal of port 323. Loss of fluid from enclosure 321
allows the enclosure to collapse so that retention members 328, 330
may return to the insertion state. Thus, catheter 320 may be
withdrawn along the passage without injury to the catheterized
mammal. In the event of traumatic proximal force applied to
catheter 320, fluid exits from enclosure 321, such as by collapse
or rupture thereof. The fluid release allows catheter 320 to
withdraw without injury.
[0145] Referring to FIGS. 16 and 17, a catheter 420 includes a
distal portion 426 including first and second retention members
428, 430 comprising first and second enclosures 429, 431. In the
insertion state seen in FIG. 16, the enclosures 429, 431 are
substantially free of added fluid so that the enclosures do not
extend radially thereby allowing catheter 420 to be inserted along
a passage. In the retention state seen in FIG. 17, the enclosures
included added fluid, such as a liquid, which is preferably saline.
The fluid expands the enclosures 429, 431 radially, thereby
extending retention members 428, 431. Proximal portion 424 of
catheter 420 may include spatial markers so that retention members
428, 430 may be extended in a known orientation within the cavity,
such as in the coronal plane within the bladder of a human.
[0146] A proximal portion 424 of catheter 420 includes a port 423
in fluid communication with a lumen 433, which extends from port
423 to enclosures 429, 431. Port 423 may be identical with port 333
of catheter 320 to allow introduction of fluid, such as a liquid to
lumen 433. Lumen 433 may bifurcate and include openings 435 to
enclosures 429, 431. Fluid entering lumen 433 enters and expands
enclosures 429, 431, which extend radially. Once enclosures 429,
431 of retention members 428, 431 are radially extended within a
cavity of a mammal, proximal motion of catheter 420 is thereby
inhibited.
[0147] Distal portion 426 of catheter 420 includes cavities 447,
449 into which enclosures 429, 431 may collapse when in the
insertion state. Respective walls 443, 445 separate cavities 447,
449 from lumen 432. Enclosures 429, 431 may be formed of material
such as plastic or other polymer. Enclosures 429, 431 may be
secured to catheter 420, such as by using, for example, at least
one of friction, adhesives or ultrasonic welding. Expansion from an
insertion state to a retention state preferably increases a radial
extent of retention members 428, 430 as compared to any increase of
a distal extent thereof. For example, the increase in radial extent
may be at least 2, at least 3, or even at least 4 times greater
than the increase in distal extent.
[0148] Catheter 420 includes a second lumen 432 running
substantially along an elongate body 422 of the catheter. Lumen 432
may operate in accordance with lumen 32 of catheter 20, such as to
allow urine to exit a bladder of a catheterized human. A distal
surface 441 of catheter 420 includes an opening 438 to lumen 432.
An opening 439 may be provided at a distal end 436 of catheter
420.
[0149] Referring to FIGS. 18-20, a catheter retention device 534 is
configured to be operatively secured to an elongate body 522 to
provide a catheter that may be inserted along a passage of an
animal so that the catheter retention device resides within a
cavity of the mammal. The elongate body is preferably a flexible
member defining at least one lumen 532 therealong. Suitable
flexible members include tubing formed of medical grade rubber,
plastic or other polymers. Once inserted, the catheter retention
device 534 may be moved to a retention state, which resists
proximal motion of the associated elongate body along the passage.
The retention device 534 is preferably a urinary catheter retention
device configured for insertion along a urethra to a bladder of a
human.
[0150] Retention device 534 includes a base 541, which is
associated with a distal end 440 of the elongate body 522. To
increase the association of retention device 533 and elongate body
522, a proximal extension 537 of retention device 534 may extend
along a lumen 532 of elongate body 522. A distal opening 538 of
base 541 allows fluid to pass between the cavity and lumen 532 of
elongate body 522. At least one of base 541 and extension 537 may
be secured to elongate body 522. For example, catheter retention
device 534 may be secured to the elongate body 522 using, for
example, at least one of friction, adhesives or ultrasonic
welding.
[0151] Retention device 534 includes at least first and second
retention members 528, 530, which may be similar or identical with
other described retention members of catheters in accordance with
the present invention. Thus, in the insertion state, retention
members 528, 530 form a distal body defining a central axis
a.sub.51. Retention members 528, 530 are movably associated with
retention device 534. Preferably, retention members are rotatably
associated with base 441 of retention member device 534 so that, in
the retention state, distal ends 533, 535 of retention members 528,
530 extend radially from central axis a.sub.51.
[0152] Retention members 528, 530 of retention device 534 may be
actuated similarly or identically with other described retention
members of catheters in accordance with the present invention. For
example, retention device 534 may include a linkage 546 having
first and second linkage members 552, 554. A tension member 574 may
be used to actuate linkage 546 by applying a proximal tension
thereto so that retention device moves from an insertion state seen
in FIG. 18 to a retention state seen in FIGS. 19 and 20. Retention
members of catheter retention devices of the invention are
configured to resist proximal motion of the associated catheter in
the absence of traumatic proximal forces. In response to a
traumatic proximal force, the retention members are configured to
return to the insertion state to allow withdrawal with a reduced
risk of injury to the catheterized individual.
[0153] Referring to FIGS. 21 and 22, a catheter 620 includes a
distal portion 626 having a yoke 623, which operably supports a
retention member 628. An elongate body 622, which extends
proximally from distal portion 626, includes a lumen 632. An
opening 638 allows fluid to enter lumen 632, pass therealong, and
exit catheter 620 at a proximal portion 624 thereof.
[0154] In an insertion state, seen in FIGS. 21 and 22, retention
member 628 is generally aligned with a central axis a.sub.62 of a
distal portion 627 of elongate body 622 and at least partially
enclosed by yoke 623. For example, a portion of retention member
628 may be accommodated by a cavity 635 of yoke 623. Thus, catheter
620 may be inserted along a passageway of a mammal until retention
member 628 is disposed within a cavity of the mammal. As discussed
below, an operator may selective move the retention member 628 to a
retention state, in which first and second ends 629, 631 of
retention member 628 are spaced apart radially from axis a.sub.62
thereby resisting proximal motion of the catheter 620 along the
passageway. When retention member is disposed in the retention
state in a cavity, such as a bladder, opening 638 is in fluid
communication with the cavity so that fluid may exit the cavity
through lumen 632 of catheter 620.
[0155] Retention member 628 is preferably rotatably associated with
yoke 623. For example, retention member 628 may rotate about a
pivot point 638 with respect to yoke 623. Pivot point 638 may be
aligned with a rotation axis a.sub.63 of retention member 728.
Thus, in moving between the insertion state and the retention
state, retention member 628 may rotate with respect to axis
a.sub.62 about rotation axis a.sub.63, which may be disposed along
retention member 628 between first and second ends 629, 631. Axis
a.sub.63 is preferably but is not required to be disposed
substantially central to first and second ends 629, 631.
[0156] A tension member 640 may be used to actuate movement of the
retention member 628 between the insertion and retention states.
Tension member 640 may be secured to retention member 628 at a
point 642, which is spaced apart radially from pivot point 638.
Thus, when tension is communicated through tension member 640 to
retention member 628, the latter rotates about pivot point 638
thereby moving from the insertion state to the retention state. To
withdraw catheter 720, a stylet or trocar may be inserted along
lumen 632 to push against a distal surface 644 of retention member
628 thereby urging the retention member to return to the insertion
state.
[0157] Referring to FIGS. 25 and 26, a catheter 720 includes a
retention member 728 and an elongate body 722 having a proximal
portion 724 and a distal portion 727. A lumen 732 extends generally
along elongate body 722. An opening 738 provides passage for fluid
to enter lumen 732 at distal portion 727 of elongate body 722 and
pass along lumen 732 to proximal portion 724.
[0158] Retention member 728 includes first and second ends 729,
731. In an insertion state, shown in FIG. 25, first and second ends
729, 731 are generally aligned with elongate body 722 to allow
insertion thereof along a passageway, such as a urethra, of a
mammal. First end 729 may be bifurcated so as to include spaced
apart end first ends 729a, 729b. In a retention state, shown in
FIG. 26, first and second ends 729, 731 are radially spaced apart
from elongate body 722 to thereby resist proximal movement of
catheter 720 along the passageway.
[0159] Retention member 728 is associated with distal portion 727
of elongate body 722 by one and preferably at least two tension
members 735. Tension members 735 are preferably secured to elongate
body 722 and to a medial portion 743 of retention member 728.
Tension members 735 are preferably elastic and, in the insertion
state, urge retention member 728, via the medial portion 743,
toward a distal end 739 of elongate body 722. Because first-ends
729a, 729b are preferably arcuate or canted to one side, the action
of tension members 735 causes retention member 728 to rotate about
a medially disposed axis a.sub.7 thereof. The rotation of retention
member 728 draws medial portion 743 further toward a distal end of
elongate body 722 thereby causing first and second ends 729, 731 to
extend radially from elongate body 722 so that catheter 720 assumes
a retention state as shown in FIG. 26. Because the medial portion
743 moves toward the elongate body 722 upon moving from the
insertion state to the retention state, an axial distance d.sub.71
between the generally medial portion of the retention member and
distal end 739 of the elongate body decreases by at least about one
half upon moving from the insertion state to the retention
state.
[0160] To insert or withdraw catheter 720 along a passageway, such
as a urethra, an operator may insert a stylet 748 or trocar along
lumen 732 of the catheter until a distal end of the stylet 748 or
trocar reaches a notch 750 of retention member 728. A distal end
752 of notch is preferably aligned with or distal to medial portion
743. Thus, as stylet 748 presses against distal end 752 of notch
750, retention member 728 assumes an insertion state as shown in
FIG. 25 thereby allowing catheter 720 to be inserted or withdrawn
along a passageway.
[0161] Once the catheter 720 has been inserted along a passageway
so that opening 738 of lumen 732 is in fluid contact with a cavity,
the operator may remove stylet 748 thereby allowing catheter 720 to
return to the retention state.
[0162] Referring to FIGS. 27-29, a catheter 820 includes first and
second retention members 828, 830 moveably associated therewith.
Catheter 820 also includes an elongate body 822, which may have a
lumen 832 therethrough in accordance with the elongate bodies of
other catheters discussed herein. For example, lumen 832 may
provide a passage for fluid from a distal portion 827 of elongate
body to a proximal portion of the elongate body. Only a distal
portion 827 of elongate body 822 is shown in FIGS. 27-29. It should
be understood, however, that elongate body 822 may be similar or
identical to elongate bodies of other catheters discussed
herein.
[0163] Catheter 820 may include a base 841, which is associated
with a distal end 840 of the elongate body 822. A proximal
extension 837 may extend partially along lumen 832 from base 841. A
distal opening 838 of base 841 allows fluid to pass between a body
cavity and lumen 832. At least one of base 841 and extension 837
may be secured to elongate body 822. For example, base 841 and/or
extension 837 may be secured to the elongate body 822 using, for
example, at least one of friction, adhesives or ultrasonic
welding.
[0164] First and second retention members 828, 830 are preferably
rotatably associated with catheter 820. In the embodiment of FIGS.
27-29, retention members 828, 830 are rotatably associated with
base 841 by flexible connections 842, 844. Alternatively, the
rotatable association may be accomplished by other elements, such
as pivots or ball and socket joints.
[0165] A linkage member 846 is operatively associated with the
first and second retention members 828, 830. In an insertion state,
as shown in FIG. 27, the linkage member 846 inhibits the retention
members 828, 830 from moving apart as toward a retention state.
Linkage member 846 may be actuated by an actuation member 874 to
actuate movement of retention members 828, 830 from the insertion
state to the retention state. In a retention state, as shown in
FIGS. 28, 29, the linkage member 846 inhibits the retention members
828, 830 from moving toward one another as toward an insertion
state. Thus, in the retention state, retention members 828, 830 may
operate to retain a catheter in a body cavity in accordance with
other retention members discussed herein. Preferably, the body
cavity is a bladder and retention of the catheter 820 provides
fluid contact between the bladder and an opening 838 to lumen
832.
[0166] A first linkage end 862 of linkage member 846 is both
rotatably and slidably associated with retention member 828. First
linkage end 862 may include projections 867 that engage retention
member 828, as by engaging a track 869 therealong. A second linkage
end 864 of linkage member 846 is both rotatably and slidably
associated with retention member 830. Second linkage end 864 may
include projections 871 that engage retention member 830, as by
engaging a track 873 therealong.
[0167] When retention members are disposed in the insertion state
shown in FIGS. 27, 28, a projection 847 of linkage member 846
engages a notch 849 of retention member 828 thereby preventing
distal ends 833, 835 of retention members 828, 830 from moving
apart radially with respect to one another. Actuation of linkage
member 846 via actuation member 874 preferably slides linkage
member 846 longitudinally with respect to retention members 828,
830 to thereby disengage linkage member projection 847 and
retention member notch 849. For example, linkage member 846 may be
actuated by applying tension to actuation member 874 thereby
sliding linkage member 846 proximally along tracks 869, 873 in the
direction of arrows 875 seen in FIG. 27.
[0168] Upon disengagement of projection 847 and notch 849, distal
retention member ends 833, 835 may move radially with respect to
one another toward the retention state shown in FIGS. 28, 29. As
distal retention member ends 833, 835 move radially, retention
member 828 rotates with respect to first linkage member end 862 and
retention member 830 rotates with respect to second linkage member
end 864. First and second linkage member ends 862, 864 may continue
to slide with respect to retention members 828, 830 as the
retention members move toward the retention state.
[0169] When in the retention state, as seen in FIGS. 28, 29,
projections 867 of first linkage member end 862 engage narrowed
portions 877 of tracks 869 and projections 871 of second linkage
member end 864 engage narrowed portions 879 of tracks 873. The
engagement of projections 867, 871 and respective narrowed portions
877, 879 inhibits linkage member 846 from sliding with respect to
retention members 828, 830 thereby inhibiting the retention members
from returning to the insertion state. Thus, when retention members
828, 830 are disposed in a body cavity in the retention state, the
retention members will be retained in the body cavity absent a
traumatic force applied to the retention members.
[0170] When in the retention state within a body cavity, linkage
member 846 and retention members 828, 830 preferably resist
proximal movement of catheter 832 for proximally applied forces of
less than about 12 Newtons, such as less than about 10 Newtons, for
example, less than about 8 Newtons, applied to elongate body 22,
but return to an insertion state to permit injury free withdrawal
of catheter 20 upon application of a force less than about 25
Newtons, such as a force of less than about 20 Newtons, for
example, a force of less than about 15 Newtons.
[0171] Upon application of a traumatic force, return to an
insertion state may be facilitated by a disengagement of linkage
member 846 and narrowed portions 877, 879 of retention members 828,
830. Alternatively, linkage member 846 may include a weakened
portion, which may be a cut 881 partially through the linkage
member 846. Upon the application of a traumatic force to catheter
820 in the retention state, linkage member 846 changes shape, such
as by folding about cut 881, thereby allowing retention members
828, 830 to move toward the insertion state and withdraw without
injury to the catheterized individual. Retention members 828, 830
may also be returned to the insertion state by inserting a trocar
or stylet along lumen 832 to disengage first and second ends 862,
864 of linkage member 846 from narrowed portions of retention
members 828, 830 and/or to change the shape of linkage member 846,
such as by flexing about cut 881.
[0172] Referring to FIGS. 30A-31C, a catheter retention device 934
is configured to be operatively secured to an elongate body to
provide a catheter that may be inserted along a passage of an
animal until the catheter retention device 934 resides within a
cavity of the mammal. The elongate body is preferably a flexible
member defining at least one lumen therealong. Suitable flexible
members include tubing formed of medical grade rubber, plastic or
other polymers. Once inserted, the catheter retention device 934
may be moved to a retention state, which resists proximal motion of
the associated elongate body along the passage. The retention
device 934 is preferably a urinary catheter retention device
configured for insertion along a urethra to a bladder of a
human.
[0173] Retention device 934 includes a base 941, which, in use, is
associated with a distal end of the elongate body used with the
device. To increase the association of retention device 934 and the
elongate body, a proximal extension 937 of retention device 934 may
extend along a lumen of the elongate body. A distal opening 938 of
base 941 allows fluid, such as urine, to pass between the cavity
and the lumen of the elongate body. At least one of base 941 and
extension 937 may be secured to the elongate body. For example,
catheter retention device 934 may be secured to the elongate body
using, for example, at least one of friction, adhesives or
ultrasonic welding.
[0174] Retention device 934 may include at least a first retention
member 928 and, optionally, a second retention member 930, each of
which may be similar or identical with other retention members of
catheters in accordance with the present invention. Thus, in the
insertion state where both retention members are used, retention
members 928, 930 may form a distal body defining a central axis
ail. Retention members 928, 930 are movably associated with
retention device 934. Preferably, retention members are rotatably
associated with base 941 of retention member device 934 so that, in
the retention state, distal ends 933, 935 of retention members 928,
930 extend radially from central axis a.sub.91.
[0175] An opening motion of retention members 928, 930 may be
actuated hydraulically. In a preferred embodiment, an opening
motion of retention members 928, 930 is actuated by expansion of an
enclosure 921, such as with a fluid, such as a gas or liquid.
Saline solution is a preferred fluid. A closing motion of retention
members 928, 930 is preferably actuated by and/or accompanies a
release of fluid from enclosure 921. Upon opening or closing,
retention members 928, 930 preferably rotate about rotation axes
a.sub.93, a.sub.94 with respect to retention device 934. Rotatable
association of retention members 928, 930 and retention device 934
may be accomplished by, for example, pivots, hinges, flexible
connections, socket joints, or other rotatable connection. It
should be understood that, as an alternative to hydraulic actuation
or in combination therewith, the retention members may be actuated
by tension and/or compression as applied by an element extending
along the elongate body associated with the device 934.
[0176] Retention device 934 may include a linkage comprising a
linkage member 946 and enclosure 921. When retention device 934 is
in the insertion state, linkage member 946 resists an opening
motion of retention members 928, 930. For example, in the insertion
state, linkage member 946 may be connected to both retention
members 928 and 930. In FIG. 30A, linkage member 946 is connected
to a portion 947 of retention member 928 and a portion 948 of
retention member 930. The connection between linkage member 946 and
retention member 928 is preferably stable in that, upon opening,
linkage member 946 remains associated with retention member 928.
(FIG. 30B). The connection between linkage member 946 and retention
member 930 may be in the form of a catch and notch.
[0177] During actuation, the connection between the retention
members is preferably released or relaxed by an amount sufficient
to allow opening of the retention members. In a preferred
embodiment, expansion of enclosure 921 releases (or relaxes, the
terms are used interchangeably) the connection, preferably by
releasing the connection between linkage member 946 and retention
member 930. The introduction of fluid to the enclosure 921 expands
the enclosure from within an opening 939 of base 941. Enclosure 921
then applies a force directed generally distally against a lower
portion 951 of linkage member 946. The force urges a distal linkage
member portion 955 against retention member 928 and urges a linkage
member portion 949 generally proximally in the general direction of
arrow 953. A space 957 between linkage member 946 and retention
member 928 may be provided to allow bowing and/or rotation of the
linkage member 946. The motion of linkage member portion 949
releases the connection between linkage member 946 and retention
member 930 at portion 948 thereof.
[0178] Referring also to FIG. 32, a catheter 975 includes retention
device 934 and an elongate body 961 having a first lumen 963 in
fluidic communication with the opening 939 and enclosure 921. The
elongate body 961 may have a second lumen 983 in fluidic
communication with opening 938 to allow fluid to drain from a
catheterized mammal. The first lumen may extend to a proximal
portion 965 of the elongate body so that an operator may introduce
fluid to or withdraw fluid from enclosure 921, as desired.
[0179] In one embodiment, the first lumen is in fluidic
communication with a port 967, such as a LUER LOC connector to
which an operator may connect a syringe. Alternatively, or in
combination, the first lumen is in fluidic communication with a
proximal enclosure 970, which may include at least one of a
flexible sack and a balloon. The proximal enclosure 970 and
enclosure 921 are in fluidic communication to the extent that the
expansion of one of the enclosures preferably accompanies a
contraction of the other enclosure. Thus, for example, to actuate
opening of the retention members 928, 930, one may apply pressure
to the proximal enclosure 970 causing fluid to exit the proximal
enclosure 970 and enter the enclosure 921. The fluid communication
may be described as hydraulic communication. Enclosures 921 and 970
may each be configured to accommodate between about 0.2 cc and
about 3 cc of fluid, for example, between about 0.5 cc and about 2
cc of fluid.
[0180] First lumen 963 may include a sheath-like structure, such as
a collar movable therealong. During actuation of retention members
928, 930 from the insertion state to the retention state, the
sheath-like structure is moved over enclosure 970. Fluid may then
be introduced to enclosure 921, such as by a syringe through
portion 967. The sheathlike structure prevents expansion of
enclosure 970 during actuation. Once retention members are in the
retention state, the sheath-like structure may be removed to allow
collapse of enclosure 921 and expansion of enclosure 970 upon a
traumatic withdrawal force.
[0181] FIG. 32 shows proximal enclosure 970 in the expanded state.
Enclosure 921, which is not seen in FIG. 32, is in the contracted
state.
[0182] Enclosure 921 and proximal enclosure 970 may cooperate to
allow a closing motion of retention members 928, 930 upon
application of a traumatic force to a retained catheter.
Preferably, both enclosure 921 and proximal enclosure 970 comprise
a balloon. Upon application of a withdrawal force to a retained
catheter, retention members 928, 930 are urged together thereby
compressing enclosure 921 therebetween. Initially, enclosure 921
resists a closing motion of the retention members. However, if the
withdrawal force is a traumatic force, the compression of enclosure
921 results in a collapse thereof and an expansion of proximal
enclosure. The compression required to actuate collapse of
enclosure 921 may be determined on the basis of Pascal's principle
and La Place's law. Thus, one may choose the sizes and materials of
enclosure 921 and proximal enclosure to retain the catheter absent
a traumatic force but allow withdrawal in the event of a traumatic
force.
[0183] In the retention state, retention members 928, 930
preferably resist proximal movement of the catheter for proximally
applied forces of less than about 12 Newtons, such as less than
about 10 Newtons, for example, less than about 8 Newtons, applied
to elongate body 22, but return to an insertion state to permit
injury free withdrawal of catheter 20 upon application of a force
less than about 25 Newtons, such as a force of less than about 20
Newtons, for example, a force of less than about 15 Newtons. For
example, a catheter that resists proximal movement for proximally
applied forces of less than about 12 Newtons but returns to an
insertion state upon application of a force of less than about 20
Newtons might remain retained upon application of an 11 Newton
force but return to the insertion state upon application of a force
of 18 Newtons. Of course, such a catheter would also return to the
insertion state upon application of forces greater than 18 Newtons.
It is understood that a force of about 4.4 Newtons is equivalent to
about 1 pound of force.
[0184] A preferred attachment of enclosure 921 to base 941 allows
fluid to pass in and out of enclosure 921 through opening 939 of
base 941. Additionally, enclosure 921 should not obstruct drainage
of urine through opening 938. FIG. 31A shows that preferred
attachment of enclosure 921 to base 941 is made at radially spaced
locations 970 and 971 of opening 939.
[0185] Referring to FIGS. 31B and 31C it should be understood that
a catheter retention mechanism of the present invention may lack
one or both of retention members 928, 930. Instead, enclosure 921
may itself retain the catheter when in the expanded state. In this
embodiment, enclosure 921 may be configured to accommodate a
greater volume of fluid than when used in cooperation with
retention members 928, 930. A preferred catheter of the present
invention comprises a distal enclosure, such as a balloon,
configured to retain the catheter in a bladder of a mammal and a
proximal enclosure in hydraulic communication with the distal
enclosure. The two enclosures cooperate as described for enclosures
921, 970 in retaining the catheter and allowing withdrawal upon a
traumatic withdrawal force.
[0186] While various descriptions of the present invention are
described above, it should be understood that the various features
can be used singly or in any combination thereof. Therefore, this
invention is not to be limited to only the specifically preferred
embodiments depicted herein. Further, it should be understood that
variations and modifications within the spirit and scope of the
invention may occur to those skilled in the art to which the
invention pertains. Accordingly, all expedient modifications
readily attainable by one versed in the art from the disclosure set
forth herein that are within the scope and spirit of the present
invention are to be included as further embodiments of the present
invention.
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