U.S. patent application number 16/422716 was filed with the patent office on 2019-09-12 for valved sheath introducer for venous cannulation.
The applicant listed for this patent is C. R. Bard, Inc.. Invention is credited to James D. Beal, Mark A. Christensen, Walter H. Shang, Steven M. Smith.
Application Number | 20190274722 16/422716 |
Document ID | / |
Family ID | 34968154 |
Filed Date | 2019-09-12 |
United States Patent
Application |
20190274722 |
Kind Code |
A1 |
Christensen; Mark A. ; et
al. |
September 12, 2019 |
Valved Sheath Introducer For Venous Cannulation
Abstract
A valved sheath introducer for venous cannulation, including a
valve, sheath, handle and cap. The valve is configured to permit
safe introduction and removal of medical instruments through the
sheath introducer. The valve may have one or more anchoring members
and a thickened central portion through which a slit is formed. The
central portion may have one or more concave surfaces and the slit
can be angled with respect to the top surface of the valve. The cap
is attached to the handle, compressing a portion of the valve
therebetween.
Inventors: |
Christensen; Mark A.; (Salt
Lake City, UT) ; Shang; Walter H.; (Irvine, CA)
; Smith; Steven M.; (Sandy, UT) ; Beal; James
D.; (South Jordan, UT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
C. R. Bard, Inc. |
Murray Hill |
NJ |
US |
|
|
Family ID: |
34968154 |
Appl. No.: |
16/422716 |
Filed: |
May 24, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14749514 |
Jun 24, 2015 |
10307182 |
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16422716 |
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|
12648533 |
Dec 29, 2009 |
9108033 |
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14749514 |
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11119599 |
May 2, 2005 |
7637893 |
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12648533 |
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60566896 |
Apr 30, 2004 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y10T 137/788 20150401;
Y10T 137/7885 20150401; Y10T 29/49405 20150115; Y10T 29/49826
20150115; A61B 17/3415 20130101; A61M 39/0693 20130101; A61M
25/0662 20130101; Y10T 29/49412 20150115; A61B 17/3498
20130101 |
International
Class: |
A61B 17/34 20060101
A61B017/34; A61M 39/06 20060101 A61M039/06 |
Claims
1. A method of making a sheath introducer, comprising: coupling a
handle to a sheath having a lumen, the handle including: a bore
communicating with the lumen; a first receiving section; and a
second receiving section; inserting a valve into the handle,
comprising: inserting a central portion of the valve into the bore,
the central portion having a first thickness, the central portion
including a slit through the first thickness; inserting a first
anchoring member of the valve into the first receiving section, the
first anchoring member having a second thickness; and inserting a
second anchoring member of the valve into the second receiving
section, the second anchoring member having the second thickness;
and attaching a cap to the handle under pressure to compress a
portion of the valve between the cap and the handle.
2. The method of making according to claim 1, wherein the coupling
step comprises insert molding the handle over a proximal end of the
sheath.
3. The method of making according to claim 1, wherein the first
receiving section of the handle is on a first side of the bore, and
wherein the second receiving section of the handle is on a second
side of the bore opposite of the first side of the bore.
4. The method of making according to claim 1, wherein the central
portion of the valve has a thickness greater than a portion of the
valve surrounding the central portion.
5. The method of making according to claim 1, wherein the central
portion of the valve has a concave surface on one side thereof.
6. The method of making according to claim 5, wherein the central
portion of the valve has opposing concave surfaces.
7. The method of making according to claim 1, wherein the central
portion of the valve has a diameter approximately equal to a
diameter of the bore of the handle.
8. The method of making according to claim 1, wherein the handle
includes opposing slotted regions between the first receiving
section and the second receiving section.
9. The method of making according to claim 8, wherein the slit of
the valve is perpendicularly aligned with the opposing slotted
regions.
10. The method of making according to claim 9, further comprising
looping a wire through the slit, wherein the inserting step
comprises disposing both a first end of the wire and a second end
of the wire in either the first receiving section or the second
receiving section of the handle.
11. The method of making according to claim 1, wherein the slit
forms an acute angle with respect to a top surface of the
valve.
12. The method of making according to claim 1, wherein the slit of
the valve is positioned in a center of the central portion, and
wherein the valve further comprises a second slit aligned with the
slit, the second slit positioned at an outer edge of the valve.
13. The method of making according to claim 12, wherein the valve
further comprises a third slit aligned with the slit, and wherein
the third slit is positioned at a first edge of the valve and the
second slit is positioned at a second edge of the valve opposite of
the first edge of the valve.
14. The method of making according to claim 13, wherein the handle
includes opposing slotted regions between the first receiving
section and the second receiving section, and wherein the second
slit and the third slit are aligned with the opposing slotted
regions.
15. The method of making according to claim 1, wherein the slit of
the valve is positioned in a center of the central portion, and
wherein the valve further comprises a first notch aligned with the
slit, the first notch positioned at an outer edge of the valve.
16. The method of making according to claim 15, wherein the valve
further comprises a second notch aligned with the slit, wherein the
first notch is positioned at a first edge of the valve and the
second notch is positioned at a second edge of the valve opposite
of the first edge of the valve.
17. The method of making according to claim 16, wherein the handle
includes opposing slotted regions between the first receiving
section and the second receiving section, and wherein the first
notch and the second notch are aligned with the opposing slotted
regions.
18. The method of making according to claim 1, wherein the
attaching step comprises ultrasonically welding the cap to the
handle.
19. The method of making according to claim 1, wherein the coupling
step comprises coupling a first part of the cap to a first side of
the handle and attaching a second part of the cap to a second side
of the handle such that a gap between the first part of the cap and
the second part of the cap is aligned with one or more slotted
regions in the handle.
20. The method of making according to claim 1, wherein the first
thickness is less than the second thickness.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/749,514, filed Jun. 24, 2015, now U.S. Pat.
No. 10,307,182, which is a division of U.S. patent application Ser.
No. 12/648,533, filed Dec. 29, 2009, now U.S. Pat. No. 9,108,033,
which is a division of U.S. patent application Ser. No. 11/119,599,
filed May 2, 2005, now U.S. Pat. No. 7,637,893, which claims the
benefit of U.S. Provisional Application No. 60/566,896, filed Apr.
30, 2004, each of which is expressly incorporated by reference as
if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] Introducer devices are commonly utilized for inserting
medical devices, such as venous access catheters, into patients.
Typically, such introducer devices comprise a peel-away sheath and
a hub/handle assembly which is used in conjunction with a dilator
assembly to access the vein of a patient, following insertion of a
needle and guidewire. In particular, procedures for introducing a
catheter into a blood vessel include the cut-down method and the
Seldinger technique. The Seldinger technique involves first
inserting a needle through the skin of a patient and into a vein to
be catheterized, inserting a guidewire through the needle and into
the vein, removing the needle from the guidewire and inserting the
dilator and introducer sheath over the guidewire and into the vein,
simultaneously removing the dilator and guidewire from the
introducer sheath, inserting a catheter through the introducer
sheath and into position within the accessed vein. Following
insertion of the catheter, the introducer sheaths are generally
designed such that they can be peeled away from the catheter,
without affecting the catheter positioning within the vein. Such
introducer sheaths and assemblies are described, for example, in
U.S. Pat. No. 4,772,266 to Groshong, issued Sep. 20, 1988, and U.S.
Pat. No. 4,306,562 to Osborne, issued Dec. 21, 1981, each of which
is incorporated by reference herein.
[0003] Problems, however, with the above-described procedure
include, 1) that upon removal of the dilator and guidewire from the
sheath, blood loss through the sheath can occur, and 2) that the
introducer sheath provides a conduit for the introduction of air
into the patient's vein, which can result in air embolism.
Moreover, the risk of air embolism increases in proportion to the
diameter size of the indwelling sheath, meaning that larger
diameter sheaths routinely used for the placement of larger
diameter catheters would increase such risk. Thus, there have been
a variety of solutions proposed, which involve the incorporation of
a valve in the proximal end of the introducer sheath, which would
allow passage of a guidewire and dilator while simultaneously
preventing blood loss or the introduction of air through the
sheath. Such proposed solutions can be found, for example, in U.S.
Pat. No. 5,125,904 to Lee, issued Jun. 30, 1992, U.S. Pat. No.
5,397,311 to Walker et al., issued Mar. 14, 1995, U.S. Pat. No.
6,083,207 to Heck, issued Jul. 4, 2000, each of which is
incorporated by reference herein.
[0004] The aforementioned and similarly directed patents are
concerned primarily with providing an elastic valve structure that
provides hemostasis and the prevention of blood loss or bleed back
for arterial cannulation procedures where there is significant
positive blood pressure. On the other hand, with respect to venous
cannulation, blood pressure is much lower and negative pressures
may be involved, meaning that while prevention of blood loss is an
ancillary concern, it is the prevention of air embolism that is the
most crucial consideration. Thus, there exists the need for a
valved sheath introducer designed for particular use for venous
cannulation.
BRIEF SUMMARY OF THE INVENTION
[0005] Accordingly, the present invention is directed to a valved
sheath introducer for venous cannulation. In one embodiment of the
invention, the valve in the introducer includes a thin disk with a
central slit and includes features such as opposing anchors to
allow stretching of the disk when a medical device is inserted
therethrough, a thickened central portion through which a
self-sealing slit is positioned, which promotes optimal resealing
upon removal of a medical device, and mechanical or other means of
splitting the disk simultaneous to the breaking and separating of a
sheath handle from an inserted medical device. In one embodiment,
the thickened central portion or island has a concave surface. Some
embodiments of the valve include slits or notches aligned with the
central slit to facilitate separation of the valve when the sheath
and handle are removed from an inserted medical device.
[0006] In another embodiment of the invention, an apparatus for
insertion of a medical device into a body comprises a sheath
comprising a sheath body and a handle, the handle including at
least one receiving section, a valve comprising a slit through a
central portion thereof and at least one anchoring member
configured for insertion into the handle receiving section, the
anchoring member being positioned along an edge of the valve, and a
cap attached to the handle, at least a portion of the valve being
compressed therebetween. In another embodiment, a wire is looped
through a slit positioned in the valve, such that when the handle
is separated and removed from medical device inserted through the
valved sheath introducer, the wire cuts the valve into two
portions.
[0007] In one aspect of the valved sheath introducer, the valve is
designed to provide optimal sealing when removing an instrument,
such as a dilator. The optimal sealing occurs due to the
configuration of the valve, such as a central portion or island and
one or more anchoring members, and the way in which the valve is
tightly held between a handle and a cap. Thus, upon removal of an
instrument from the introducer sheath, the valve body, which is
stretched as the instrument is inserted therethrough, rebounds
toward the handle but cannot resume its original position due to
the pressure exerted by the cap and the handle. The result is a
bunching or duckbill effect of the valve that provides a desirable
seal.
[0008] These and other embodiments, features and advantages of the
present invention will become more apparent to those skilled in the
art when taken with reference to the following more detailed
description of the invention in conjunction with the accompanying
drawings that are first briefly described.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 illustrates a side perspective view of one embodiment
of a valved sheath introducer with an inserted dilator.
[0010] FIG. 2 illustrates a side perspective view of the sheath
introducer of FIG. 1 in isolation.
[0011] FIG. 3 illustrates a top view of the handle of the sheath
introducer of FIG. 2.
[0012] FIG. 4 illustrates a bottom view of one embodiment of a
valve for a valved sheath introducer.
[0013] FIG. 5 illustrates a side view of the valve of FIG. 4.
[0014] FIGS. 6A and 6B illustrate a cross-sectional view of the
valve of FIG. 4.
[0015] FIG. 7 illustrates a bottom view of another embodiment of a
valve for a valved sheath introducer.
[0016] FIG. 8 illustrates a bottom view of yet another embodiment
of a valve for a valved sheath introducer.
[0017] FIGS. 9A-9D illustrates an advantageous feature of one
embodiment of a valve for a valved sheath introducer.
[0018] FIG. 10 depicts an alternate embodiment of a valve for a
valved sheath introducer along with a handle and cap prior to
assembly.
[0019] FIG. 11 depicts the valve of FIG. 10 in isolation with the
handle.
[0020] FIG. 12 is a cross-sectional assembled view of the cap,
handle and valve of FIG. 10.
[0021] FIG. 13 is a further cross-sectional view of the cap, handle
and valve of FIG. 12.
[0022] FIG. 14 is an alternate embodiment of a valve with an
island, the island having a concave surface.
[0023] FIG. 15 is a cross-sectional view of the valve of FIG.
14.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The following detailed description should be read with
reference to the drawings, in which like elements in different
drawings are identically numbered. The drawings, which are not
necessarily to scale, depict selected embodiments and are not
intended to limit the scope of the invention. The detailed
description illustrates by way of example, not by way of
limitation, the principles of the invention. This description will
clearly enable one skilled in the art to make and use the
invention, and describes several embodiments, adaptations,
variations, alternatives and uses of the invention, including what
is presently believed to be the best mode of carrying out the
invention.
[0025] The present invention involves valves and valved sheath
introducers used particularly in venous cannulation procedures.
However, it should be appreciated that while the designs described
herein are intended for such use, they may be equally suitable for
a variety of other uses (e.g., arterial cannulation, introduction
of pacing leads, etc.) and therefore should not be so limited.
Further, while sheath introducers and sheath introducer assemblies
are described herein for exemplary purposes of housing and
implementation of the subject valves, it should be appreciated that
many different configurations and types of sheath introducers and
sheath introducer assemblies would be equally suitable for use with
the valves of the present invention and therefore should in no way
serve to limit the scope of the valves described herein. In
addition, as used in this specification and the appended claims,
the singular forms "a," "an" and "the" include plural referents
unless the context clearly dictates otherwise. Thus, for example,
the term "a slit" is intended to mean a single slit or more than
one slit.
[0026] Referring now to FIGS. 1 and 2, a valved sheath introducer
assembly 10 according to one embodiment is shown, including a
valved sheath introducer 20 and a dilator 50. The valved sheath
introducer assembly 10 is shown in its insertion configuration with
dilator 50 inserted completely through the valved sheath introducer
20 and locked thereto. The valved sheath introducer 20 includes a
sheath body 22, a handle 30, a cap 40, and an internal valve 100
(FIG. 4). In this embodiment, the handle 30 has a first side 32 and
a second side 34 separated by two slots 36, positioned
approximately 180.degree. apart. The sheath body 22 has a tapered
distal end 24 to facilitate insertion into a blood vessel. In one
embodiment, the sheath body 22 is made of polytetrafluoroethylene
(PTFE) and the handle 30 and cap 40 are made of K-Resin.RTM.
(styrene-butadiene copolymer). In another embodiment, the handle 30
and cap 40 are made of Cryolite.RTM. (poly(methyl methacrylate)).
Of course, other materials are also possible for the sheath body,
handle and cap, including other polymer materials (e.g.,
polycarbonate, thermoplastics, etc.), as is apparent to one of
ordinary skill in the art.
[0027] In an exemplary manufacturing process for the valved sheath
introducer 20, the handle 30 is insert molded over the proximal end
26 of the sheath body 22. After molding, the valve 100 is placed on
the top of the handle 30, and the cap 40 is attached to the handle
30 (e.g., via ultrasonic weld, adhesives, screws, etc.) over the
valve 100 under force. In one exemplary manufacturing method, the
attachment method is ultrasonic welding wherein the sheath body 22
and handle 30 are placed into an ultrasonic welder and the cap 40
is pressed onto the handle 30 after the valve 100 has been set
therein. The ultrasonic welder sends vibrations through the cap 40,
causing a portion of the cap 40 and handle 30 to meld together. In
one embodiment, the cap 40 is in two part form prior to welding
such that a small gap in alignment with the slots 36 can be
provided. In a top view of the handle 30, shown in FIG. 3 prior to
attachment of the valve 100 and cap 40, slots 36 can be seen in
more detail as can the handle bore 39, which is configured to be
approximately the same diameter as that of the lumen of the valved
sheath introducer 20. In addition, valve receiving sections 38 can
be seen configured to accommodate valve anchors 102, 104 (FIG. 4),
as will be explained in more detail below.
[0028] Referring back to FIG. 1, the dilator 50 includes a threaded
luer connector 52, which rotates independently of the dilator body
56, and is configured for mating with the cap 40 to lock the
dilator 50 to the valved sheath introducer 20. The body 56 has a
diameter approximately equal to that of the lumen of the valved
sheath introducer 20 and also has a tapered distal end 58 to
provide ease of insertion of the valved sheath introducer assembly
10 into a blood vessel. The dilator 50 also includes a luer
connection 54 at the proximal end thereof for attachment to devices
used for purposes such as flushing. An injection cap (not shown)
may also be placed over the proximal end of the dilator.
[0029] FIGS. 4-6B illustrate one embodiment of a valve 100 for
incorporation into a valved sheath introducer. FIG. 4 is a bottom
view of valve 100, which is a thin disk-like body 108, including
valve anchors 102, 104 around the circumferential edge of the body
108 and disposed on the back side thereof. The valve anchors 102,
104 extend from the body 108, as can be seen in FIGS. 5 and 6A, and
are configured in size and shape to correspond with the valve
receiving sections 38 of the handle 30 (FIG. 3) to ensure that the
valve 100 remains in axial position as instruments are inserted
therethrough and withdrawn therefrom, and also to ensure that the
valve 100 properly separates (each side of the valve remaining with
its respective side of the handle into which it is held) upon
removal of the sheath introducer 20 from an inserted
instrument.
[0030] FIG. 6A is a cross-section of the valve of FIG. 4 taken
along line 6A-6A, showing the relative thickness of the island 106
compared to the opposing anchors 102, 104. As shown in this
embodiment, the island thickness is slightly less than that of the
anchors, although in other embodiments, the island thickness is
either the same or greater than the thickness of the anchors. In
still other embodiments, the anchors 102, 104 have different
thicknesses, each of which may be greater than, less than or equal
to the island thickness. Also, in the embodiments shown, the
anchors 102, 104 have rounded edges 116, although other
configurations, including edges with opposing right angles, are
certainly contemplated herein. FIG. 6B illustrates another
embodiment of the valve 100, including a slit 110A that is cut
through the middle region of the valve 100, traversing at an angle
from a top surface of the valve to a bottom surface thereof (e.g.,
to a surface of the island 106) that is different from the
approximately 90.degree. angle with respect to the top surface of
the valve shown in FIG. 6A. While the slit 110A is shown as cut at
approximately a 45.degree. angle, certainly any other non-parallel
angle with respect to the top surface of the valve is possible as
should be appreciated by one of ordinary skill in the art.
[0031] The anchors 102, 104 allow for a tight tolerance with
respect to the positioning of the valve 100 within the handle 30,
being tightly secured therein by the cap 40, as explained above.
This tight tolerance results in an advantageous reaction by the
valve 100 with respect to sealing thereof upon removal of an
instrument that had previously been inserted therethrough (e.g.,
dilator, etc.). In particular, in concert with the island 106,
which is a circular feature positioned in the center of the body
108, extending along with the anchors 102, 104 from the bottom
thereof, a superior seal is created upon removal of an instrument
from the sheath introducer 20, as will be explained below in
connection with FIGS. 9A-9D. It should be appreciated that while
the valve 100 has a circular shape and the valve anchors 102, 104
have a semi-circular shape, as seen in FIG. 4, various shapes and
sizes are possible and contemplated herein to correspond with the
shape and size of the handle and receiving sections onto/into which
they are positioned.
[0032] In the embodiment shown in FIG. 4, approximately
equidistantly spaced on the edge of the body 108 between the valve
anchors 102, 104 on opposite sides of the body 108 are peripheral
slits 112, 114, which enable the valve 100 to be easily split in
half along the line extending from slit 112 to slit 114. These
slits can also be in the form of notches having various shapes, two
of which (122, 124 and 132, 134) are illustrated in FIGS. 7 and 8.
While the notches shown are in the shapes of triangles and
trapezoids, other shapes are possible and are contemplated herein
to facilitate the separation of the valve 100. A central slit 110
through which instruments can be inserted is cut through the valve
body 108 and island 106 and is positioned approximately centrally
with respect to the edges of the valve 100. While only one slit is
shown, in other embodiments two or more slits are formed through
the valve in different patterns. For instance, in one embodiment,
multiple slits are cut through the valve in a pattern similar to an
asterisk when viewed from the top or bottom thereof. As discussed,
when the valve 100 is placed into the handle 30, the valve anchors
102, 104 are positioned in receiving sections 38 of the handle 30,
which places the island 106 within the opening of the handle bore
39. Such alignment results in the slits 112, 114 being aligned with
the slots 36 of the handle 30.
[0033] The following materials and dimensions are provided as an
example of one embodiment and should not be taken as limiting the
invention in any way. The valve 100 in this embodiment is made of
silicone (Dow Corning Q7-4840), having a diameter of approximately
0.516 inches, while the diameter of the island 106 is approximately
0.260 inches and the distance between inner edges of the islands
102, 104 is approximately 0.420 inches (the width of the anchors
thus being approximately 0.048 inches). The thickness of the valve
100 along the anchors 102, 104 is approximately 0.090 inches, while
the thickness of the valve across the island is approximately 0.045
inches, the remainder of the body therefore having a thickness of
approximately 0.025 inches. The distance between the anchors 102,
104 is approximately 0.160 inches on both sides of the valve 100.
The central slit 110 has a length of approximately 0.204 inches,
while the peripheral slits 112, 114 have a length of approximately
0.050 inches. In other embodiments, the dimensions are dependent
upon the size of the instrument(s) being inserted through the
valve.
[0034] With respect to the valve island 106, another embodiment is
shown in FIGS. 14 and 15. Valve 300 is shown, including one or more
anchors 302 and an island 306 that has a concave surface 304
extending into the thickness of the valve body 308 and a slit 310.
The slit 310 as shown is positioned at an angle of approximately
60.degree. with respect to the top surface of the valve, although
as stated above in connection with FIGS. 6A and 6B, any other
non-parallel angle with respect to the top surface of the valve is
possible. The curvature of the concave surface can be more or less
than shown and can extend short of, or up to, the line of the valve
body in other embodiments. The depth of the concavity is also
variable, which alters the thickness of the mid-point of the island
in different embodiments. As shown in FIG. 15, the edges of the
island are curved, although as with the anchors, other types of
edges are possible. Numerous embodiments are contemplated with
respect to the configuration of the island and slits or notches in
the valve. For instance, the valve could have a concave surface on
the island along with notches on opposing sides of the valve, the
valve could have a concave surface on the island and an opposing
concave surface on the top of the valve with no slits or notches,
the valve could have notches or slits but no island, etc.
[0035] FIGS. 9A-9C depict the configuration of one side of the
valve 100 with respect to the handle 30 and the cap 40 as an
instrument is inserted therethrough (FIG. 9B) and withdrawn
therefrom (FIG. 9C). An imaginary grid is provided to aid in the
illustration of the movement and positioning of the valve 100 with
respect to the handle 30 and the cap 40. It should be appreciated,
however, that the grid is exemplary only and isn't intended to
depict actual distances or precise intervals. In FIG. 9A, the valve
100 is tightly held between the handle and the cap prior to
insertion of an instrument therethrough. Close inspection of the
valve 100 reveals that the thickness of the valve material 150
between the handle 30 and the cap 40 is slightly less than the
thickness of the valve material 160 outside of this area (i.e.,
within the handle bore 39). This is due to the pressure exerted
onto the valve 100 as the cap 40 is attached to the handle 30 as
explained above. As can be seen, the distance between the marks on
the grid line in FIG. 9A are the same for both valve material 150
and 160.
[0036] FIG. 9B depicts the movement of the valve 100 upon insertion
of an instrument therethrough, the valve material 160 stretching
and experiencing a reduction in thickness such that the thickness
thereof is approximately equivalent to the thickness of valve
material 150 (although certainly the thickness of the valve
material 160 could be greater than or equal to the valve material
150 as it is stretched upon insertion of an instrument through
valve 100). In addition to the thickness of the valve, this
demonstration of stretching is evidenced by the increased distance
between the marks on the grid line along valve material 160.
Although the valve material 150 is still held tightly between the
cap 40 and the handle 30 while an instrument is inserted through
the valve 100, stretching of the material does occur. This action
is revealed in FIG. 9B by the grid line as the distance between the
marks on the grid line is shown to increase. It is noted here that
while the material adjacent to the anchors stretches slightly upon
insertion of an instrument through the valve 100, the anchors
themselves remain in position inside the receiving sections of the
handle.
[0037] FIG. 9C depicts the valve 100 upon removal of the inserted
instrument, at which point the valve material 150 and 160 rebounds
back toward the side of the handle 30. However, because the valve
material 150 is tightly held between the cap 40 and the handle 30,
a bunching effect occurs as stretched valve material 150 that has
moved from an original position between the handle 30 and cap 40
toward the center of the valved introducer 20 is prevented from
returning to its original position. This phenomenon is illustrated
by the grid line in FIG. 9C, which shows the distance between marks
in valve material 150 to be approximately the same as the distance
in FIG. 9B, whereas the distance between marks in valve material
160 has slightly decreased. This bunching effect leads to a
duckbill-like configuration for the valve 100 as shown in FIG. 9D,
which illustrates the configuration of the central region of the
valve following removal of an instrument. Such a configuration
provides a superior seal over the valves of the prior art. In one
embodiment, the valve 100 is provided with a lubricant in order to
ease the surface friction between the valve and inserted
instrument, thus maintaining the desired duckbill shape.
[0038] Removal of the sheath introducer 20 from an instrument
inserted therethrough (e.g., a catheter) is effectuated by grasping
the handle 30 on each side thereof and pulling the sides in
opposite directions so that the handle 30 cracks along the slots
36. Upon cracking and splitting of the handle 30, the integrated
valve 100 tears along the slit line created by central slit 110 and
peripheral slits 112, 114, the tearing process enabled, as
discussed above, by the anchors 102, 104, which maintain the
position of each side of the valve 100 within the respective side
of the handle. As the two pieces of the handle are pulled away from
one another, the sheath peels down its entire length at the
circumferential location of the handle slots (which correspond to
the aligned pre-split sections of the sheath). Due to the extrusion
process for manufacturing the PTFE, which results in an alignment
of the molecules, the peeling of the sheath is continuous down the
entire length thereof at the circumferential locations without the
need for score line(s). The handle does not detach from the sheath
during or after the splitting process. In other embodiments of the
invention, the sheath is made from PTFE or another like polymer
material with one or more score lines positioned longitudinally
along the length of the sheath in line with the slot(s) in the
handle.
[0039] In another embodiment of a valved sheath introducer, a very
thin wire is associated with the valve, as shown in FIGS. 10-13.
FIG. 10 illustrates a handle 230, a cap 240 and a valve 200, which
includes a single anchor 202 and a thin wire 204, prior to
assembly. The wire 204 is looped through the central slit of the
valve 200 and each end extends beyond the edge of the valve 200,
being coupled together for positioning in the handle 230. The
central slit of valve 200 is oriented perpendicular to the slots of
the handle 230, differently than the axial alignment of valve 100
described above. It should be noted that in this view, the cap 240
has an extension pattern 242 configured to be received within a
like shaped extension pattern in the handle 230 for an improved
connection therebetween. FIG. 11 illustrates the valve 200 placed
into the handle 30. FIG. 12 illustrates the interaction of the
handle 230, cap 240 and valve 200 by showing a cutaway view of the
cap 240 and handle 230 with a top perspective view of the valve,
while FIG. 13 shows another cutaway view of the handle 230 and cap
240 with a cross-sectional view of the valve 200 also being
shown.
[0040] In FIG. 13, the side of the handle 230 that receives the
wire 204 can be seen to also have an empty receiving section 238
due to the fact that the valve 200 does not contain an anchor for
positioning therein. While in some embodiments, this empty section
does not exist, in this particular embodiment the presence of
receiving sections in both sides of the handle 230 facilitates
manufacture of the valved sheath introducer by permitting
positioning of the anchor 202 in either side of the handle. When
the handle 230 is broken to remove from an inserted instrument
(e.g., a catheter), the wire 204 remains with the half of the
handle 230 into which the extension thereof has been set (FIG. 11),
while the valve 200 remains with the opposite half, into which the
anchor 202 is set (FIGS. 12, 13). Thus, as the halves of the handle
230 are pulled in opposite directions, the wire 202 cuts the valve
200, slicing it into two parts for easy removal from the inserted
instrument.
[0041] The valved sheath introducer described herein is used
according to one embodiment as follows. After an access site on a
body is determined and an incision made, the valved sheath
introducer assembly is inserted into the body with a distal end of
the sheath body extending into a body vessel to be accessed.
Following optional preparatory steps (e.g., flushing), the dilator
is removed from the valved sheath introducer. As the dilator is
removed, the valve closes as described above in connection with
FIGS. 9A-9C. A catheter or other medical device can then be
inserted through the valved sheath introducer and into the body
vessel. When the desired positioning of a more permanent medical
device, such as a catheter, has been accomplished, the valved
sheath introducer is ready to be removed. In one embodiment, the
handle is cracked by pulling a first side and a second side of the
handle in opposite directions (i.e., away from the inserted medical
device). This cracking action may take place, for example, along
slots positioned in the handle between the first and second sides.
By pulling the handle apart, the valve is separated such that one
portion remains with the first side of the handle and another
portion remains with the second side of the handle, as is described
in exemplary embodiments herein. Once the handle is broken and the
first and second sides are continued to be pulled in approximately
opposite directions away from the inserted medical device, the
sheath body is torn down its length so that complete removal of the
valved sheath introducer from around the inserted medical device is
possible without affecting the positioning of the medical device in
the body vessel.
[0042] This invention has been described and specific examples of
the invention have been portrayed. While the invention has been
described in terms of particular variations and illustrative
figures, those of ordinary skill in the art will recognize that the
invention is not limited to the variations or figures described. In
addition, where methods and steps described above indicate certain
events occurring in certain order, those of ordinary skill in the
art will recognize that the ordering of certain steps may be
modified and that such modifications are in accordance with the
variations of the invention. Additionally, certain of the steps may
be performed concurrently in a parallel process when possible, as
well as performed sequentially as described above. Therefore, to
the extent there are variations of the invention, which are within
the spirit of the disclosure or equivalent to the inventions found
in the claims, it is the intent that this patent covers those
variations as well. Finally, all publications and patent
applications cited in this specification are herein incorporated by
reference in their entirety as if each individual publication or
patent application were specifically and individually put forth
herein.
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