Note: Descriptions are shown in the official language in which they were submitted.
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PUNCTURE CLOSURE SYSTEM WITH PIN AND PULL TECHNIQUE
FIELD OF THE INVENTION
[0002] The present invention relates to facilitating hemostasis at a puncture
site. More
particularly, the present invention relates to facilitating hemostasis at a
puncture site by
delivering a hemostasis promoting material to the blood vessel puncture site
using a pin
and pull technique.
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BACKGROUND OF THE INVENTION
[0003] A large number of diagnostic and interventional procedures involve the
percutaneous introduction of instrumentation into a vein or artery. For
example, coronary
angioplasty, angiography, atherectomy, stenting of arteries, and many other
procedures
often involve accessing the vasculature through a catheter placed in the
femoral artery or
other blood vessel. Once the procedure is completed and the catheter or other
instrumentation is removed, bleeding from the punctured artery must be
controlled.
[0004] Traditionally, external pressure is applied to the skin entry site to
stem bleeding
from a puncture wound in a blood vessel. Pressure is continued until
hemostasis has
occurred at the puncture site. In some instances, pressure must be applied for
up to an
hour or more during which time the patient is uncomfortably immobilized. In
addition, a
risk of hematoma exists since bleeding from the vessel may continue beneath
the skin
until sufficient clotting effects hemostasis. Further, external pressure to
close the
vascular puncture site works best when the vessel is close to the skin surface
but may be
unsuitable for patients with substantial amounts of subcutaneous adipose
tissue since the
skin surface may be a considerable distance from the vascular puncture site.
[0005] There are several prior art devices that try to overcome the
disadvantages of the
traditional external pressure application. For example, there are devices that
place a
hemostat within the bloodstream of the vessel, within the wall of the blood
vessel, or
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adjacent to the wall of the blood vessel puncture site to close the puncture.
However,
reliance is on tactile sensation alone to indicate to the surgeon the proper
placement of
the puncture closing instrumentation. Other prior art references require a
separate device
for locating the blood vessel puncture site which is must then be removed for
insertion of
a second device to expel a hemostat. Still other prior art devices use bleed
back ports to
locate the blood vessel puncture site in conjunction with other devices such
as a foot plate
placed against the blood vessel wall or closure devices with anchors. However,
in these
prior art devices a surgeon is then required to use sutures and/or needles to
close the
blood vessel puncture. Moreover, in some of the prior art devices, external
pressure
applied at the surface of the skin may still be required.
[0006] Thus, there is still a need to perform the closing of a blood vessel
puncture site
with a more efficient and easier apparatus and method. There is a need for an
apparatus
and method to both accurately locate the blood vessel puncture site as well as
facilitate
hemostasis utilizing one instrument. Moreover, there is a need for a method
and
apparatus that can provide for the ex-vivo loading of a hemostat, provide for
a more
accurate location of the blood vessel puncture site, and is able to deliver a
hemostat to the
blood vessel puncture site all in a single pass. Furthermore, there is a need
for an
apparatus and method that can accurately deliver a hemostat in various
positions that the
surgeon desires or believes is best for the patient.
BRIEF DESCRIPTION OF THE INVENTION
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[0007] The present invention provides for a method and apparatus to facilitate
hemostasis
at a blood vessel puncture site having a cannula with a distal end, a proximal
end, an
inner diameter, and a lumen extending between said distal end and said
proximal end; a
bleed back port located near the distal end; a pusher having a top, a bottom,
and a lumen
extending between the top and bottom, the bottom is slidably received into the
cannula
lumen; a bleed back exit port located near the top; and a pledget having a
first end and a
second end, the first end positioned at the distal end within the cannula
lumen, and the
second end positioned below the bleed back port.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying drawings, which are incorporated into and constitute a
part of
this specification, illustrate one or more embodiments of the present
invention and,
together with the detailed description, serve to explain the principles and
implementations
of the invention.
In the drawings:
FIG. 1 illustrates an apparatus within a blood vessel lumen to facilitate
hemostasis
at a blood vessel puncture site in accordance with one embodiment of the
present
invention.
FIG. 2 illustrates an apparatus to facilitate hemostasis at a blood vessel
puncture
site in accordance with another embodiment of the present invention.
FIGS. 3A and 3B illustrates an apparatus to facilitate hemostasis at a blood
vessel
puncture site in accordance with yet another embodiment of the present
invention.
FIGS. 4A-4H illustrates the various pledgets positioned within the blood
vessel
lumen.
FIGS. 5A-5B illustrates the pledget positioned within the blood vessel wall.
FIGS. 6A-6B illustrates the pledget positioned adjacent the blood vessel
puncture
site.
FIGS. 7A-7H illustrates a method for facilitating hemostasis at a blood vessel
puncture site.
FIGS. 8A-8D illustrate embodiments of the pledget in accordance with the
present
invention.
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DETAILED DESCRIPTION
[0009] Embodiments of the present invention are described herein in the
context of a
puncture closure system with pin and pull technique. Those of ordinary skill
in the art
will realize that the following detailed description of the present invention
is illustrative
only and is not intended to be in any way limiting. Other embodiments of the
present
invention will readily suggest themselves to such skilled persons having the
benefit of
this disclosure. Reference will now be made in detail to implementations of
the present
invention as illustrated in the accompanying drawings. The same reference
indicators
will be used throughout the drawings and the following detailed description to
refer to the
same or like parts.
[0010] In the interest of clarity, not all of the routine features of the
implementations
described herein are shown and described. It will, of course, be appreciated
that in the
development of any such actual implementation, numerous implementation-
specific
decisions must be made in order to achieve the developer's specific goals,
such as
compliance with application- and business-related constraints, and that these
specific
goals will vary from one implementation to another and from one developer to
another.
Moreover, it will be appreciated that such a development effort might be
complex and
time-consuming, but would nevertheless be a routine undertaking of engineering
for
those of ordinary skill in the art having the benefit of this disclosure.
[0011] Referring now to Fig. 1, an embodiment of the present invention
illustrating an
apparatus within a blood vessel lumen to facilitate hemostasis at a blood
vessel puncture
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site. The apparatus 100, comprises a delivery cannula 102 having a distal end
106, a
proximal end 104, an inner diameter 108, and a lumen 110 extending between the
distal
end 106 and the proximal end 104. The cannula 102 may also have a bleed back
port 112
located near the distal end 106 of the cannula 102 to detect blood flow out of
the blood
vessel lumen. The present invention allows for the synergistic coexistence of
both a
hemostatic agent and a bleed back system. Both do not compete or detract from
each of
their functions which allows a user to locate the blood vessel puncture site
using visual
bleed back indication and to deploy a hemostatic agent to the blood vessel
puncture site
in one single pass.
[0012] The apparatus 100 may have a pusher 116 with a top 118, a bottom 120,
and a
lumen 122 extending between the top 118 and bottom 120. The pusher bottom 120
may
be placed inside the cannula lumen 110 such that the pusher 116 may be able to
slidably
move within the cannula lumen 110. The pusher bottom 120 may have a diameter
equal
to or less than the inner diameter of the cannula 108. The diameter may be as
small as 1
French, but preferably greater than 3 French. Moreover, it is preferable that
the pusher
bottom 120 have a diameter substantially equal to the inner diameter of the
cannula 108
to maximize visual bleed back indication as further discussed below. The
pusher top 118
may have a pair of finger levers 124a and 124b to assist a user in holding the
pusher 116
in a fixed position or to assist in moving the pusher 116 within the cannula
lumen 110.
However, those of ordinary skill in the art will now realize that any other
means for
grasping or holding the pusher 116 may be used.
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[0013] The pusher 116 may also have a bleed back exit port 126 located near
the pusher
top 118. Blood flow entering the apparatus 100 from the bleed back port 112
will flow
through the pusher lumen 122 and out the bleed back exit port 126 as indicated
by arrow
128. Alternatively, as shown in Fig. 2, another embodiment of the present
invention
illustrating an apparatus to facilitate hemostasis at a blood vessel puncture
site, the bleed
back exit port 202 may be located near the cannula proximal end 104. In this
case, blood
will flow from the bleed back port 112, through the cannula lumen 110, and out
the bleed
back exit port 202 as indicated by arrow 204.
[0014] When the bleed back port 112 is located within the blood vessel lumen
114, a
steady stream of blood will flow out of the bleed back exit port 126. However,
when the
bleed back port is positioned outside the blood vessel lumen (not shown) or
within the
wall of the blood vessel, blood will not steadily flow out of the bleed back
exit port 126.
This visual indication of blood flow out of the bleed back exit port 126, 202
assists a user
in positioning the apparatus 100 at the blood vessel puncture site 118.
[0015] To maximize the visual effects of bleed back, it is preferable that the
lumen 110
and the plunger lumen 122, through which the blood flows to the bleed back
exit port
126, 202 be maximized. The present invention allows for an accurate visual
bleed back
indication by maximizing the lumen 110 through the use of a cannula 102. To
further
provide accurate visual bleedback indication it is preferable that the pusher
lumen 122 be
substantially equal or between about 0.5 French to 0.2 French smaller than the
inner
diameter of the cannula 108 as shown in Fig. 1. Alternatively, as shown in
Fig. 2, it is
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preferable that obstructions within the cannula lumen 110 be eliminated and
the pusher
bottom 120 be positioned above the bleed back exit port 202.
[0016] In an alternative embodiment, as shown in Figs. 3A and 3B, the pusher
302 may
be a stylet and disk or any other similar type of pusher 312. In these
embodiments, the
bleed back exit port 304 is located near the cannula proximal end 104. The
pusher 302
may have a disk or piston 306, a top 308, and an extension 310 between the
disk 306 and
the top 308. As shown in Figs. 3A and 3B, the stylet may be attached to the
disk as a
single unit, may be attached to the disk by other means such as a string 314,
or the stylet
and disk may not be attached together. The disk 306 may be located below the
bleed
back port 112 adjacent the pledget second end 133. The disk 306 may have a
diameter
substantially equal to the inner diameter of the cannula 108, but it may be
smaller than
the inner diameter of the cannula 108. It is preferable that the diameter of
the extension
or stylet 310 be as small as possible, for example less than 3 French, yet be
strong enough
to eject the pledget 130 from the cannula 102. This allows for maximum space
within the
cannula lumen 110 for blood to flow from the bleed back port 112 to the bleed
back exit
port 304. Moreover, the stylet may be configured in any shape such as a shaft
as shown
in Figs. 3A and 3B or as a plenum (not shown) to divide the cannula lumen into
two or
more lumens.
[0017] The apparatus 100 may also have a pledget 130 compressed within the
cannula
lumen 110 at the cannula distal end 106. The pledget 130 is positioned below
the bleed
back port 112 such that the pledget serves as the distal "seal" or the
boundary of the
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bleed back circuit. The pledget 130 may be any biocompatible material,
preferably a
sponge. Preferably, the sponge is non-immunogenic and may be absorbable,
dissolved or
resorbed by the body, or non-absorbable. Non-absorbable pledgets may include
various
polymeric foams, such as polyurethanes, as are well-known in the art.
Absorbable
sponges may include those made from Gelatin, Colagen, Oxydized Cellulose, PGA,
and
other like materials.
[0018] The pledget 130 may also have a coagulant or clot formation
accelerating agent
such as Thrombin, Fibrinogen (Biomolecules), Protamine, and additives that can
create a
negative or positive charged pledget such as calcium chloride, magnesium,
ferric
chloride, or an acid such as hydrochloric acid, and other similar additives.
The
coagulants are used to effect local hemostasis and chemically activate a
clotting cascade.
The coagulants may be incorporated into the pledget as part of the gelatin
formation or
may be applied as a coating to the surface of a pledget.
[0019] The pledget 130 may be pre-hydrated to facilitate rapid expansion or
the pledget
130 may contain a wetting agent for rapid expansion of the pledget with or
without pre-
hydrating the pledget. The pledget 130 may be pre-hydrated in various ways as
disclosed
in detail in U.S. Patent No. 6,071,301, filed May 1, 1998, entitled "Device
And Method
For Facilitating Hemostasis Of A Biopsy Tract" by inventors Andrew H. Cragg,
Rodney
Brenneman, and Mark Ashby and U.S. Patent No. 6,162,192, filed May 1, 1998,
entitled
"System And Method For Facilitating Hemostasis Of Blood Vessel Punctures With
Absorbable Sponge" by inventors Andrew H. Cragg, Rodney Brenneman, and Mark
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Ashby. Wetting agents are discussed in detail in co-pending U.S. Patent
Publication No.
20030028140, filed February 4, 2002, entitled "Cross-Linked Gelatin
Composition
Comprising A Wetting Agent" by inventor Richard J. Greff. The wetting agents
may be
incorporated into the pledget as part of the gelatin formation or may be
applied as a
coating to the surface of a pledget.
[0020] The pledget 130 may also comprise a surface coating made of bioadhesive
agents
to increase surface traction and/or adhesion which will increase grip and
friction between
the surrounding tissue or artery wall and pledget. This will ensure that the
pledget
remains within the lumen of the blood vessel, intraarteriotomy the blood
vessel wall, or
within the tissue tract adjacent the blood vessel puncture site. The
bioadhesive agent may
be a permanent tissue adhesive and/or bonding agent such as cyanoacrylates or
fibrin
derived compositions. Alternatively, the bioadhesive agent may be
mucoadhesives that
are triggered by moisture such as blood. Some synthetic mucoadhesives are
polyvinyl
carboxylic acids such as polyacrylic and methacrylic acids. Examples of such
acids are
Carbopol-974 NF (high performance polymer) and Noveon-AA1 sold by Noveon, Inc.
located in Cleveland, Ohio. Additionally, cellulosics and polysaccarides may
be used
such as Poly(methyl vinyl ether - alt - Melaic Anhydride), Carboxymethyl
Cellulose (sodium salt), and Chitosan (high molecular weight) sold by Aldrich
Chemical
Company, Inc. located in Milwaukee, WI. The bioadhesive agents may be
incorporated
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into the pledget as part of the gelatin formation or may be applied as a
coating to the
surface of a pledget.
[00211] As shown in Figs. 4B-4E, the pledget 130 may comprise a securing
mechanism at
the pledget first end 132 to secure the pledget to the blood vessel lumen 114,
the
intraarteriotomy the blood vessel wall, or provide friction and/or traction to
the blood
vessel wall. Alternatively, the securing mechanism may be located proximally
of the
pledget first end 132 along the pledget length, including at the pledget
second end 133, to
secure the deployed pledget against any movement. As shown in Fig. 4B, the
securing
mechanism may be a pair of lateral projections 400a, 400b or more centrally
originating
star configuration 402, or a retention flange 410 or proximal shoulders 413 on
the outer
surface of a distal dissolvable tip 412 as shown in Figs. 4G and 4H. Other
proximally
located pledget securing mechanisms may be used such as the expandable clip
800 shown
in Fig. 8A, the proximal shuttlecock 802 shown in Fig. 8B, the expandable
pineapple 804
shown in Fig. 8C, a trampoleen or umbrella frame 806 as shown in Fig. 8D, or
other
gripping features such as a crisscross surface, expandable braid, ridges, or
bumps to
prevent proximal movement after the pledget is deployed. All of these securing
mechanisms can be retained within the cannula lumen in a non-deployed position
(not
shown) and upon deployment from the cannula, the securing features activate as
shown in
Figs. 8A-D. As shown in Fig. 4C, illustrating a pledget in a non-deployed
state, the
lateral projections 400a, 400b may be retained within the cannula lumen 110 at
the
cannula distal end 106 prior to deployment. After the pledget 130 is deployed,
the lateral
projections 400a, 400b expand as shown in Fig. 4D. The lateral projections may
be made
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of any biocompatible material such as various polymers that are well known in
the art.
The lateral projections may also be made of non-absorbable materials such as
SST,
nitinol, titanium, or other biocompatible metals. The projections may also be
made of
absorbable polymers such as PGA, Gelatin, methyl cellulose, carboxymethyl
cellulose,
carbowaxes, and gelatin (particularly pigskin gelatin). Among the suitable
polymers are
polylactic glycolic acids, polyvinyl pyrrolidone, polyvinyl alcohol,
polyproline, and
polyethylene oxide.
[0022] In yet another embodiment, the pledget first end 132 may extend
partially out of
the cannula distal end 106 as shown in Fig. 4F. Thus, the pledget first end
132 will have
a diameter equal to the outside diameter of the cannula 404.
[0023] Additionally, the pledget first end 132 may have different
characteristics than the
pledget second end 133. For example, the first end 132 may vary in traction,
stickiness,
hardness, dissolution rate, thrombocinicity, shape, or other similar
characteristics from
the second end 133.
[0024] As shown in Fig. 1, the pledget 130 may have a first end 132 and a
second end
133 where the first end 132 may be positioned immediate the cannula distal end
106. It is
preferable that the diameter of the pledget first end 132 be substantially
equal to the inner
diameter of the cannula 102 to prevent blood from flowing though the cannula
distal end
106. The second end 133 may be positioned below the bleed back port 112. The
pledget
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130 may expand when exposed to fluids such as blood or when expelled out of
the
cannula lumen 110.
[0025] The embodiments above may be used with or without a guidewire 136 or
other
locating device. If used with a guidewire 136, the entire pledget 130 may have
an axial
passage (not shown) through its length, S, to receive a guidewire or the like.
If used
without a guidewire, the present invention may be placed within an existing
procedural
sheath already positioned within the artery or blood vessel (not shown).
However, if a
procedural sheath is used, the bleed back port 112 must extend beyond the
procedural
sheath distal end such that bleed back may be detected to properly position
the apparatus
100.
[0026] To locate the apparatus 100 in the proper position, the user may insert
the
apparatus 100 down the tissue tract until the bleed back port 112 enters the
blood vessel
lumen 114 as indicated by when bleeding is first observed exiting the bleed
back exit port
126. The user may then withdraw the apparatus' 100 out of the blood vessel
lumen 114
until the bleed back port 126 is located within the wall of the blood vessel
134 as
indicated by when bleeding is no longer observed exiting the bleed back exit
port 126.
[0027] After the apparatus 100 is positioned in the proper position at the
blood vessel
puncture site 128 as shown in Fig. 1, the pledget 130 may be positioned in
several
positions to facilitate hemostasis at the blood vessel puncture site 128. One
position may
be within the blood vessel lumen, as shown in Figs. 4a and 4b. Another
position may be
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within the blood vessel wall or intraarteriotomy 500 as shown in Figs. 5a and
5b. Still
another position may be adjacent the wall of the blood vessel 134 as shown in
Fig. 6.
[0023) To position the pledget 130 within the blood vessel lumen 114 as shown
in Figs.
4a and 4b, distance D (Fig. 1), the distance between the cannula distal end
106 and the
bleed back port 112, may be greater than or equal to distance S, the length of
the pledget
130. Moreover, distance S may be greater than distance P, the distance between
the bleed
back port 112 and the pusher bottom 120. With the pusher 116 in a fixed or
pinned
positioned, the cannula 102 may be pulled back a distance R such that the
cannula
proximal end 104 is adjacent the pusher top 118. Distance R may be greater
than or
equal to the sum of distances D and P. The pledget first end 132 is positioned
approximately a distance S-P within the blood vessel lumen 114.
[0029] When using a pledget 130 with a securing mechanism at the pledget first
end 132,
the cannula 102 may be pulled back a distance R or in the alternative, the
cannula 102
may be fixed and pusher 116 pushed down a distance R where R is described by:
Minimum distance to expose the securing mechanism < R < D+P (1)
Distance R may be less than the sum of distances D and P such that only the
securing
mechanism is exposed beyond the cannula distal end 106 when the cannula 102 is
pulled
back a distance R or the pusher 116 is pushed down distance R as shown in FIG.
7D. In
this position, the securing mechanism is exposed within the blood vessel lumen
704 and
expands. The cannula 102 and pusher 116 may then be simultaneously pulled out
of the
tissue tract such that the securing mechanism catches the inside wall of the
blood vessel
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134 which secures the pledget 130 at the blood vessel puncture site 128 to
facilitate
hemostasis.
[0030] To position the pledget 130 within the wall of the blood vessel as
shown in Figs.
5a and 5b, the distance D (Fig. 1), the distance between the cannula distal
end 106 and
the bleed back port 112, may be greater than or equal to distance S, the
length of the
pledget 130. Moreover, distance S is equal to distance P, the distance between
the bleed
back port 112 and the pusher bottom 120. With the pusher 116 in a fixed or
pinned
positioned, the cannula 102 may be pulled back a distance R such that the
cannula
proximal end 104 is adjacent the pusher top 118. Distance R may be greater
than or
equal to the sum of distances D and P.
[0031] As shown in Fig. 7D, when using a pledget 130 with a securing mechanism
at the
pledget first end 132, the cannula 102 may be pulled back a distance R or in
the
alternative, the cannula 102 may be fixed and pusher 116 pushed down a
distance R,
where R is described as follows:
[0032] Minimum distance to expose the securing mechanism < R < D+P (2)
Distance R may be less than the sum of distances D and P such that only the
securing
mechanism is exposed beyond the cannula distal end 106 when the cannula 102 is
pulled
back a distance R or the pusher 116 is pushed down distance R. In this
position, the
securing mechanism is exposed within the blood vessel lumen 704 and expands.
The
cannula 102 and pusher 116 may then be simultaneously pulled out of the tissue
tract
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such that the securing mechanism catches the inside wall of the blood vessel
134 which
secures the pledget 130 at the blood vessel puncture site 128 to facilitate
hemostasis.
[0033] To position the pledget 130 adjacent the blood vessel puncture site 128
as shown
in Fig. 6A, distance D (Fig. 1), the distance between the cannula distal end
106 and the
bleed back port 112, may be greater than or equal to distance S, the length of
the pledget
130. Moreover, distance S may be less than distance P, the distance between
the bleed
back port 112 and the pusher bottom 120. With the pusher 116 in a fixed or
pinned
positioned, the cannula 102 may be pulled back a distance R such that the
cannula
proximal end 104 is adjacent the pusher top 118. Distance R may be greater
than or
equal to the sum of distances D and P. The pledget first end 132 is positioned
approximately a distance P-S outside the blood vessel puncture site 128. As
illustrated
in Fig. 6B, a pledget with distally extending lateral prongs 600a and 600b may
also be
used to effectively place the pledget 130 adjacent the blood vessel puncture
site 128.
[0034] When using the embodiments in Fig. 2 or Fig. 3, once the apparatus 100
is
properly positioned at the blood vessel puncture site 128, the pusher bottom
306 is then
positioned at distance P prior to deployment of the pledget 130. The distance
P may vary
depending on whether the pledget 130 is deployed within the blood vessel
lumen, within
the blood vessel wall, or adjacent the blood vessel puncture site.
[0035] Figs. 7A-7H illustrates a method for facilitating hemostasis at a blood
vessel
puncture site. As shown in Fig. 7A, a cannula 700 has a bleed back port 706 at
the
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cannula' distal end 708 and a pledget 710 positioned below the bleed back port
706. The
cannula 700 and pusher 702 are advanced into the blood vessel lumen 704 until
the bleed
back port 706 is located within the blood vessel lumen 704. In this position,
blood flows
into the bleed back port 706, through the pusher lumen 712, and out a bleed
back exit
port 714 as indicated by arrow 724. When the bleed back port 706 is located
within the
blood vessel lumen 704, a steady stream of blood will flow out of the bleed
back exit port
714. However, when the bleed back port is positioned outside the blood vessel
lumen or
within the wall of the blood vessel as further discussed below in Fig. 7B,
blood will not
steadily flow out of the bleed back exit port 714. This visual indication of
blood flow out
of the bleed back exit port 714 assists a user in positioning the apparatus
716 at the blood
vessel puncture site 718.
[0036] The apparatus may be used with or without a guidewire 722 or other
locating
device. If used with a guidewire 722, the pledget 710 may have an axial
passage (not
shown) through its length to receive a guidewire or the like. If used without
a guidewire,
the present invention may be placed within an existing procedural sheath
already
positioned within the artery or blood vessel (not shown). However, if a
procedural sheath
is used, the bleed back port 706 must extend beyond the procedural sheath
distal end
such that bleed back may be detected to properly position the apparatus 716.
[0037] Alternatively, the bleed back exit port 202 may be located near the
cannula
proximal end as shown in Fig. 2. In this embodiment, blood will flow from the
bleed
back port 112, through the cannula lumen 110, and out the bleed back exit port
202. It is
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preferable that the cannula lumen 110 have little to no obstructions to
maximize blood
flow through the lumen to the bleed back exit port 202 to provide an accurate
visualization of bleed back. Thus, it is preferred that the pusher bottom 120
be
positioned above the bleed back exit port 202. Alternatively, as shown in
Figs. 3A and
3B, the pusher 302 may be a stylet and disk or any other similar type of
pusher 312. As
illustrated in Figs. 3A and 3B, the stylet may be attached to the disk as a
single unit, may
be attached to the disk by other means such as a string 314, or the stylet and
disk may not
be attached. The disk 306 may be located below the bleed back port 112
adjacent the
pledget second end 133. The disk 306 may have a diameter equal to or less than
the inner
diameter of the cannula. The disk diameter may be as small as 1 French, but
preferably
greater than 3 French. It is also preferable that the diameter of the stylet
or extension 310
be as small as possible, such as less than 3 French, yet be strong enough to
eject the
pledget from the cannula. This allows for maximum space within the cannula
lumen 110
for blood to flow from the bleed back port 112 to the bleed back exit port
304. Moreover,
the stylet may be configured in any shape such as a shaft as shown in Figs. 3A
and 3B or
as a plenum (not shown) to divide the cannula lumen into two or more lumens.
[0038] Fig. 7B shows the apparatus later in time than Fig. 7A. The cannula
700, pledget
710, bleed back port 706, and pusher 702 are simultaneously withdrawn from the
blood
vessel lumen 704 until bleed back is no longer visible out of the bleed back
exit port 714.
This informs a user that the apparatus 716 is located at or near the blood
vessel puncture
site 718.
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[0039] The pledget 710 may be discharged to facilitate hemostasis once the
apparatus is
positioned at the proper position. When using embodiments of Figs. 2 and 3,
the pusher
116 may be repositioned at distance P prior to deployment of the pledget 130.
The
distance P may vary depending on whether the pledget 710 is deployed within
the blood
vessel lumen, within the blood vessel wall, or adjacent the blood vessel
puncture site as
further discussed below.
[0040] The pledget 710 may be positioned in several positions to facilitate
hemostasis at
the blood vessel puncture site 718. One position is within the blood vessel
lumen 704 as
shown in Figs. 7C - 7E. Another position is within the blood vessel wall or
intraarteriotomy 742 as shown in Figs. 7F and 7G. Still another position is
adjacent the
wall of the blood vessel 718 as shown in Fig. 7H.
[0041] To position the pledget 710 within the blood vessel lumen 704 as shown
in Figs.
7C-7E, distance D (Fig. 7B), the distance between the cannula distal end 708
and the
bleed back port 706, may be greater than or equal to distance S, the length of
the pledget
710. Moreover, distance S may be greater than distance P, the distance between
the bleed
back port 706 and the pusher bottom 726. As shown in Fig, 7C, with the pusher
702 in a
fixed or pinned positioned, the cannula 700 may be pulled back a distance R in
the
direction of arrow 732 such that the cannula proximal end 728 is adjacent the
pusher top
730. Distance R may be greater than or equal to the sum of distances D and P.
The
pledget first end 734 is positioned approximately a distance S-P within the
blood vessel
lumen 704.
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[0042] In another embodiment as shown in Figs. 7D and 7E, a pledget with a
securing
mechanism may be used. The securing mechanism may be located at the pledget
first
end, the pledget second end, or along the pledget length to secure the
deployed pledget
against any movement. The securing mechanism may be a pair of lateral
projections as
shown in Figs. 7D and 7E, an expandable clip 800 shown in Fig. 8A, the
proximal
shuttlecock 802 shown in Fig. 8B, the expandable pineapple 804 shown in Fig.
8C, a
trampoleen or umbrella frame 806 as shown in Fig. 8D, or other gripping
features such as
a crisscross surface, expandable braid, ridges, or bumps.
[0043] When using a pledget 710 with a securing mechanism 736 at the pledget
first end
734, it is compressed in its non-deployed state within the cannula lumen. With
the
pusher 702 fixed, the cannula 700 may be pulled back a distance R or in the
alternative,
cannula 700 may be fixed and pusher 702 pushed down the cannula a distance R.
Distance R may be less than the sum of distances D and P and equal to or
greater than the
length of the securing mechanism 736. Distance R is the a length such that the
securing
mechanism 736 is exposed beyond the cannula distal end 708 when the cannula
700 is
pulled back or, in the alternative, the pusher 702 is advanced down the
cannula a distance
R. In this position, as shown in Fig. 7D, the securing mechanism 736 is
exposed within
the blood vessel lumen 704 and expands. A portion or all of the pledget second
end
remains inside the cannula 700. As shown in Fig. 7E, the cannula 700 and
pusher 702
may then be simultaneously pulled out of the tissue tract in the direction of
arrow 732
such that the securing mechanism catches the inside wall of the blood vessel
740 which
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secures the pledget 710 at the blood vessel puncture site 718 to remove the
pledget 710
from the cannula 700 and facilitate hemostasis.
[0044] To position the pledget 710 within the blood vessel wall as shown in
Figs. 7F and
7G, the distance D (Fig. 7B), the distance between the cannula distal end 708
and the
bleed back port 706, may be greater than or equal to distance S, the length of
the pledget
710. Moreover, distance S is equal to distance P, the distance between the
bleed back
port 716 and the pusher bottom 726. As shown in Fig. 7F, with the pusher 702
in a fixed
or pinned positioned, the cannula 700 may be pulled back a distance R in the
direction of
arrow 732 such that the cannula proximal end 728 is adjacent the pusher top
730.
Distance R may be greater than or equal to the sum of distances D and P.
[0045] In another embodiment, as shown in Figs. 7G which is similar to Fig.
7D, when
using a pledget 710 with a securing mechanism 736 at the pledget first end
734, the
securing mechanism 736 it is compressed in its non-deployed state within the
cannula
lumen. With the pusher fixed, the cannula 700 may be pulled back a distance R
or in the
alternative, cannula 700 may be fixed and pusher 702 pushed down the cannula a
distance R. Distance R may be less than the sum of distances D and P and equal
to or
greater than the length of the securing mechanism 736. Distance R is the a
length such
that only the securing mechanism 736 is exposed beyond the cannula distal end
708 when
the cannula 700 is pulled back or, in the alternative, the pusher 702 is
advanced down the
cannula a distance R. In this position, as shown in Fig. 7D, the securing
mechanism 736
is exposed within the blood vessel lumen 704 and expands. A portion or all of
the
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pledget second end remains inside the cannula 700. As shown in Fig. 7E, the
cannula
700 and pusher 702 may then be simultaneously pulled out of the tissue tract
in the
direction of arrow 732 such that the securing mechanism catches the inside
wall of the
blood vessel 740 which secures the pledget 710 at the blood vessel puncture
site 718 to
remove the pledget from the cannula and to facilitate hemostasis.
[0046] To position the pledget 710 adjacent blood vessel puncture site 718 as
shown in
Fig. 7H, distance D (Fig. 7B), the distance between the cannula distal end 708
and the
bleed back port 706, may be greater than or equal to distance S, the length of
the pledget
710. Moreover, distance S may be less than distance P, the distance between
the bleed
back port 706 and the pusher bottom 726. As shown in Fig. 7H, with the pusher
702 in a
fixed or pinned positioned, the cannula 700 may be pulled back a distance R in
the
direction of arrow 732 such that the cannula proximal end 728 is adjacent the
pusher top
730. Distance R may be greater than or equal to the sum of distances D and P.
The
pledget first end 734 is positioned approximately a distance P-S outside the
blood vessel
puncture site 718.
[0047] While embodiments and applications of this invention have been shown
and
described, it would be apparent to those skilled in the art having the benefit
of this
disclosure that many more modifications than mentioned above are possible
without
departing from the inventive concepts herein. The invention, therefore, is not
to be
restricted except in the spirit of the appended claims.
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