U.S. patent application number 11/244168 was filed with the patent office on 2006-02-09 for methods for obtaining hemostasis of percutaneous wounds.
This patent application is currently assigned to THE TRUSTEES OF THE UNIVERSITY OF PENNSYLVANIA. Invention is credited to Timothy W. Clark.
Application Number | 20060030886 11/244168 |
Document ID | / |
Family ID | 26893516 |
Filed Date | 2006-02-09 |
United States Patent
Application |
20060030886 |
Kind Code |
A1 |
Clark; Timothy W. |
February 9, 2006 |
Methods for obtaining hemostasis of percutaneous wounds
Abstract
This invention relates to novel methods, kits, and devices for
stopping hemorrhaging of percutaneous wounds. The inventive subject
matter involves insertion of a purse-string suture around the
wound, insertion of the free two ends of the suture through a
tension collar, manual tightening of the tension collar until
hemostasis is achieved, and application of a suture lock to the
free ends of the suture to secure the tension collar and maintain
hemostasis. After a sufficient period of time to allow complete
hemostasis, the suture lock and the tension collar are loosened; if
hemostasis has been achieved, the suture lock, the tension collar,
and the suture material are removed. If bleeding continues from the
wound, the tension collar is tightened and the suture lock
reapplied. This process may be repeated until complete hemostasis
is achieved, without the need for additional suturing or manual
compression.
Inventors: |
Clark; Timothy W.;
(Philadelphia, PA) |
Correspondence
Address: |
Viviana Amzel, Ph. D.;NATH & ASSOCIATES PLLC
6th Floor
1030 15th Street
Washington
DC
20005
US
|
Assignee: |
THE TRUSTEES OF THE UNIVERSITY OF
PENNSYLVANIA
|
Family ID: |
26893516 |
Appl. No.: |
11/244168 |
Filed: |
October 6, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10198161 |
Jul 19, 2002 |
|
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11244168 |
Oct 6, 2005 |
|
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60307042 |
Jul 20, 2001 |
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Current U.S.
Class: |
606/232 |
Current CPC
Class: |
A61B 2017/00663
20130101; A61B 2017/00637 20130101; A61B 2017/00641 20130101; A61B
2017/1142 20130101; A61B 17/34 20130101; A61B 17/0057 20130101;
A61B 2017/0496 20130101; A61B 2017/00477 20130101 |
Class at
Publication: |
606/232 |
International
Class: |
A61B 17/04 20060101
A61B017/04 |
Claims
1-13. (canceled)
14. A method for producing hemostasis of a percutaneous wound,
comprising inserting a purse-string suture around a percutaneous
wound using multiple passes of a suture needle and a
physiologically suitable suture material in a manner such that a
final pass of the suture needle is oriented so as to bring the
final exit site of the suture material substantially adjacent to an
initial entry site of the suture material through the skin;
bringing the initial entry and final exit limbs of the suture
material through a tension collar; tightening the tension collar to
achieve hemostasis of the percutaneous wound; and applying a
suitable suture lock to the free ends of the suture material to
secure the tension collar.
15. The method of claim 14, wherein the percutaneous wound is
associated with the insertion of a vascular sheath, cannula or
catheter through the skin.
16. The method of claim 15, wherein the purse-string suture is
inserted through the skin contemporaneously with the vascular
sheath, cannula, or catheter.
17. The method of claim 15, wherein the vascular sheath, cannula or
catheter is removed prior to tightening the tension collar.
18. The method of claim 14, wherein the suture material comprises
monofilament 2.0 polypropylene or nylon.
19. The method of claim 14, wherein the purse-string suture is
inserted within about 3 mm of the percutaneous wound.
20. The method of claim 14, comprising releasing the suture lock
and loosening the tension collar after a sufficient period of time
is allowed for hemostasis to occur; re-tightening the tension
collar and re-applying the suture lock as needed to prevent
bleeding or oozing of blood; and removing the suture material when
satisfactory hemostasis has been achieved.
21. A percutaneous wound homeostasis kit, comprising suture(s) of
size and material characteristics suitable for the type and
location of the percutaneous wound to be treated; suture needle(s);
tension collar(s); suture-lock(s); and Instructions for use of the
kit.
22. The kit of claim 21, wherein the suture material(s) comprise(s)
a non-absorbable monofilament.
23. The kit of claim 21, wherein the suture material(s) comprise(s)
2.0 monofilament polypropylene or nylon.
Description
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 60/307,042, filed on Jul. 20, 2001, the
entire contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to novel methods for stopping
hemorrhaging of percutaneous wounds. The method comprises placement
of a purse-string monofilament suture around the wound, insertion
of the free two ends of the suture through a tension collar, manual
tightening of the tension collar until hemostasis is achieved, and
application of a suture lock to the free ends of the suture to
secure the tension collar and maintain hemostasis. After a
sufficient period of time for complete hemostasis, the suture lock
and the tension collar are loosened; if hemostasis has been
achieved, the suture lock, the tension collar, and the suture
material are removed. If bleeding continues from the wound, the
tension collar is tightened and the suture lock reapplied. This
process may be repeated until complete hemostasis is achieved,
without the need for additional suturing or manual compression. The
present invention further relates to novel kits and devices for
producing hemostasis of a percutaneous wound in an animal.
[0004] 2. Background
[0005] Manual compression is used to obtain hemostasis of
percutaneous wounds, including the puncture site following removal
of vascular sheaths, catheters, and other devices used for
percutaneous interventions. An effective device for obtaining
puncture site hemostasis without manual compression would represent
a substantial saving in physician time and improved efficiency in
patient care. Such factors are of considerable importance to
patients who must undergo repeated interventions, such as those
receiving dialysis shunts (grafts and fistulae), and most
especially those required to simultaneously take anticoagulants.
Prolonged manual compression of 30-60 minutes is often required
when anticoagulants such as heparin or large sheaths are used.
Moreover, manual compression itself may compromise blood flow
through the dialysis shunt, leading to clot formation. Similar
considerations of time and efficiency apply to the need for wound
closure of, for example, wounds caused by puncture, gunshot, or
other roughly circular injury.
[0006] Various techniques of suture closure have been described to
facilitate hemostasis at the puncture site. Many physicians have
used the purse-string technique to achieve hemostasis. Although
effective, the suture can be very difficult to remove because the
knot tends to get buried within the tissues around the puncture
sites, which can become quite puckered. The suture knot is then
just a few millimeters away from the high flow hemodialysis
vascular access and hemodialysis nurses are often reluctant to
remove the sutures at the next dialysis session. Patients returning
weeks to months after purse-string suture insertion for follow-up
interventions would still have the previous sutures left in place.
Thus, there is an acute need for a method that makes suture removal
simple and safe, and wherein the patient does not have any suture
material remaining.
[0007] Previously reported techniques for obtaining hemostasis
following percutaneous intervention or injury include purse-string
sutures with a temporary knot, a tourniquet device, or a hemostat
to tighten the purse-string suture (see Vorwerk, Konner, Schurmann,
and Gunther, a Simple Trick to Facilitate Bleeding Control after
Percutaneous Hemodialysis Fistula and Graft Interventions,
Cardiovasc Intervent Radiol. 20(2):159-60 (1997); Zaleski, Funaki,
Gentile, and Garofalo, Purse-string Sutures and Miniature
Tourniquet to Achieve Immediate Hemostasis of Percutaneous Grafts
and Fistulas: a Simple Trick with a Twist, Am. J. Roentgenol.
175(6):1643-5 (2000); and Simons, Clark, and Rajan, The Woggle
Technique: A New Method of Suture Closure of Hemodialysis
Arteriovenous Grafts and Fistulae After Percutaneous Intervention,
Journal of Vascular and Interventional Radiology 12(1):S30 (2001)).
A temporary knot fails to allow a means of providing rapid and
reversible tension on the puncture site. A tourniquet device passes
through a loop of purse-string suture and achieves hemostasis
through twisting and traction of the skin at the puncture site.
[0008] U.S. Pat. No. 6,355,050, issued to Andreas, et al., on Mar.
12, 2002 discloses a device and method for suturing a tissue layer
having two sides by releasably retaining at least a portion of the
suture in a stationary position on one side of the tissue layer,
wherein the portion of the suture is retrieved through the tissue
layer from the opposite side whereby the suture is drawn from one
side to the opposite side; in particular, Andreas, et al., disclose
devices and methods for suturing the wall of a tubular graft and a
graft anastomosis assembly.
[0009] U.S. Pat. No. 6,117,145, issued to Wood, et al., on Sep. 12,
2000, discloses a method and device for providing hemostasis at
vascular penetration sites utilizing a blood vessel puncture
occlusion device.
[0010] U.S. Pat. No. 6,036,699, issued to Andreas, et al. on Mar.
14, 2000, discloses medical devices and methods for suturing tissue
by proximally drawing sutures through a tissue layer in the
proximity of an aperture; suturing vascular tissue while
maintaining adequate perfusion or hemostasis, or both; anastomosing
a graft to an aperture in a vessel wall while maintaining
hemostasis at the anastomosis with physiological flow and/or
pressure in the vessel lumen; punching and removing tissue to form
an aperture in a vessel wall while maintaining hemostasis at the
aperture with physiological flow and/or pressure in the vessel
lumen; automatically and repeatably placing suture thread through
vessel wall tissue surrounding an aperture in the vessel wall in a
suture pattern that is useful for anastomosing a tubular graft to
the aperture; and, deploying a suture with one end extending
through the tissue that surrounds a punched aperture in a vessel
wall and the opposite suture end extending radially through a
tubular graft wall adjacent an open end of the graft, such that a
vessel anastomosis may be rapidly and repeatably performed in a
CABG procedure even while the vessel is under physiological
flow.
[0011] U.S. Pat. Nos. 6,015,428, 5,741,301, and 5,895,393, issued
to Pagedas, respectively disclose an integrally formed suture and
suture lock, a self locking suture lock, and a suture lock
holder.
[0012] Statistically, the need for improved hemostasis devices is
demonstrated by the number of prevalent patients in the United
States with end-stage renal disease, which is expected to increase
from 326,000 in 1998 to over 666,000 by 2010. Most of these
patients will receive renal replacement therapy through
hemodialysis. For a large portion of these patients, percutaneous
access will be necessary to maintain dialysis shunt function. These
patients also require ongoing periodic radiologic treatments with
angioplasty balloons, stents, and clot removal devices to maintain
dialysis shunt function. According to the United States Renal Data
System, Medicare expenditures on dialysis access totaled nearly 1
billion dollars in 1994. Since that time, progressive escalation in
the number of dialysis interventions has occurred. From 1991 to
1998, a 65% increase in prevalent dialysis patients was observed
with a 100% increase in shunt blood clot removal procedures
(declots) and a 65% increase in angioplasty and other procedures
(revisions).
[0013] The duration of bleeding is highly variable among patients
and depends on many factors, including the size of the vascular
sheath used for the treatment procedure, the dose and elimination
of heparin and other blood thinning agents, the anatomy of the
patient, and the hemodynamic pressure within the dialysis shunt.
Because patients will differ in bleeding tendency, a simple and
effective means of reapplying tension to the puncture site is
highly advantageous.
[0014] The prior art tourniquet devices pass through a single loop
of purse-string suture and achieve hemostasis through twisting and
traction of the skin at the puncture site. This produces
unnecessary distortion of the puncture site, which, in Applicant's
experience, leads to rebleeding once the tourniquet has been
loosened. The present inventive methods and devices provide
uniform, circumferential tension around the puncture site and can
be quickly reapplied when necessary, while producing minimal
distortion or traction on the skin.
[0015] Further, by removing the suture the same day as the surgery,
there is a decreased risk of infection when compared to leaving in
a suture for several days. When using the methods of the present
invention, the requirements for coagulation testing prior to
intervention may be relaxed. In patients with elevated INR, we have
successfully performed interventions without complication, although
we leave the hemostasis device on longer.
[0016] Thus, the present invention provides a simple, rapid method
for obtaining a puncture site hemostasis following percutaneous
intervention or injury, particularly of dialysis shunts and the
like. The inventive methods provide uniform, circumferential
tension around the puncture site and can be quickly reapplied when
necessary. The potential benefits and advantages over existing
techniques include rapid and reversible tension on the puncture
site, reduced twisting and traction of the skin at the puncture
site, and reduced physician intervention and improved efficiency in
patient care resulting lower cost of medical care. Further, the
inventive methods consistently obviate the need for follow-up
appointments to remove a purse-string suture at a later date.
SUMMARY OF THE INVENTION
[0017] The present invention relates to a method for producing
hemostasis of a percutaneous wound in an animal, which comprises
the steps of: [0018] (i) inserting a purse-string suture around the
percutaneous wound using multiple passes of a suture needle and a
physiologically suitable suture material, wherein a final pass of
the suture needle is oriented to bring the final exit site of the
suture material substantially adjacent to an initial entry site of
the suture material through the skin of said animal; [0019] (ii)
bringing the initial entry and final exit limbs of the suture
material through a tension collar; [0020] (iii) tightening the
tension collar until hemostasis of said percutaneous wound in an
animal is achieved; and [0021] (iv) applying a suitable suture lock
to the free ends of the suture material to secure the tension
collar.
[0022] The present invention further relates to a method for
producing hemostasis of a percutaneous wound produced by the
insertion of a vascular sheath, cannula, or catheter in the skin of
an animal, which comprises the steps of: [0023] (i) inserting a
purse-string suture within 3 mm of the percutaneous wound, using a
suture needle and a physiologically suitable suture material,
wherein said purse-string suture is produced through three or four
needle passes of monofilament 2.0 polypropylene or nylon, and
wherein a final pass of the suture needle is oriented to bring the
final exit site of the suture material substantially adjacent to an
initial entry site of the suture material through the skin; [0024]
(ii) bringing the initial entry and final exit limbs of the suture
material through a tension collar while said vascular sheath,
cannula, or catheter is inserted through the skin; [0025] (iii)
manually tightening the tension collar, after removal of said
vascular sheath, cannula, or catheter, until hemostasis is
achieved; [0026] (iv) applying a suitable suture lock to the free
ends of the suture material to secure the tension collar; [0027]
(v) releasing said suture lock and loosening said tension collar
after a sufficient period of time for hemostasis; [0028] (vi)
optionally retightening said tension collar and reapplying said
suture lock if required to prevent continued bleeding or oozing of
blood; and [0029] (vii) removing said tension collar, suture lock,
and suture material when satisfactory hemostasis has been
achieved.
[0030] The present invention also relates to a kit for producing
hemostasis of a percutaneous wound in an animal, comprising: [0031]
(a) a suture of acceptable size and material characteristics
suitable for the type and location of the percutaneous wound to be
treated; [0032] (b) a suture needle; [0033] (c) a tension collar;
and [0034] (d) a suture-lock.
[0035] Finally, the present invention relates to a body comprising
two hollow shaft portions (1) and (2), each having one or more
exterior wall(s) and an internal channel (3), and a cavity portion
(4) located between said shaft portions; and [0036] (ii) a
slide-spring lock mechanism within said cavity portion for
providing a suture-locking effect within the hemostasis device,
said slide-spring lock mechanism having a plunger (5) mounted
slidably in said passage for movement relative to said cavity
portion along a predetermined axis, and having an end portion (6)
which is accessible from the outside of the cavity portion for
manually pressing the plunger inwardly along said axis from a
gripping position to a released position, said cavity portion
having one or more aperture(s) (7) and said plunger having one or
more aperture(s) (8) through which one or more suture(s) (9) can
extend generally transversely of said axis, wherein said
slide-spring lock mechanism is in sliding engagement with one or
more length(s) of suture material, said slide-spring lock mechanism
being capable of releasable locking engagement along said length(s)
of suture material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a CAD drawing which depicts a purse-string suture
placed around a percutaneous sheath, with the final pass of the
suture needle oriented to bring the exit site of the suture
material adjacent to the initial entry site of the suture material
through the skin, and two limbs of the suture material brought
through the tension collar of a releasable hemostasis device of the
present invention.
[0038] FIG. 2 is a CAD drawing which depicts a cutaway view of a
releasable hemostasis device of the present invention, with the
slide-spring lock mechanism biased in the locked "closed", or
gripping, orientation.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0039] "Adjacent" refers to things which are near in space or
position; immediately adjoining without significant intervening
space.
Methods of the Present Invention
[0040] The present invention relates to a method for producing
hemostasis of a percutaneous wound in an animal, which comprises
the steps of: [0041] (i) inserting a purse-string suture around the
percutaneous wound using multiple passes of a suture needle and a
physiologically suitable suture material, wherein a final pass of
the suture needle is oriented to bring the final exit site of the
suture material substantially adjacent to an initial entry site of
the suture material through the skin of said animal; [0042] (ii)
bringing the initial entry and final exit limbs of the suture
material through a tension collar; [0043] (iii) tightening the
tension collar until hemostasis of said percutaneous wound in an
animal is achieved; and [0044] (iv) applying a suitable suture lock
to the free ends of the suture material to secure the tension
collar.
[0045] In a preferred embodiment, the hemostasis device of the
present invention consists of a tension collar, such as a plastic
guide wire introducer, or a similar hollow, tube-shaped member
placed over the ends of a purse string suture and secured with a
suture locking device, such as a hemostat, a clamp, or a
commercially-available suture lock to tighten the suture without
making a knot. The device is applied immediately prior to removing
the sheath or catheter at the end of a procedure. The suture and
hemostasis device are left for 20-60 minutes, and then the
hemostasis device is released by means of loosening the suture
lock. If hemostasis is achieved, the suture is removed, and if
hemostasis is not achieved the hemostasis device is either
retightened or the suture is knotted and the patient
discharged.
[0046] In another preferred embodiment, said percutaneous wound
results from the insertion of a vascular sheath, cannula, or
catheter through the skin of said animal. However, the methods and
devices of the present invention are expected to be well suited to
obtaining hemostasis of other wounds such as those resulting from
gunshot, puncture with sharp implements such as knives, picks, and
screwdrivers, and other injuries producing wounds which are
substantially circular.
[0047] In another preferred embodiment, said purse-string suture is
inserted while said vascular sheath, cannula, or catheter is also
inserted through the skin. Inserting the suture while the surgical
instrument is still in place is expected to further reduce the
possibility of bleeding or infection.
[0048] In another preferred embodiment, said vascular sheath,
cannula, or catheter is removed prior to tightening said tension
collar.
[0049] In a further preferred embodiment, said suture material is
monofilament 2.0 polypropylene or nylon.
[0050] In a further preferred embodiment, said purse-string suture
is inserted within 3 mm of the percutaneous wound.
[0051] In a most preferred embodiment, said method comprises the
additional steps of: [0052] (v) releasing said suture lock and
loosening said tension collar after a sufficient period of time for
hemostasis; [0053] (vi) retightening said tension collar and
reapplying said suture lock, as required to prevent continued
bleeding or oozing of blood; and [0054] (vii) removing said suture
material when satisfactory hemostasis has been achieved.
[0055] In another preferred embodiment, the present invention
relates to a method for producing hemostasis of a percutaneous
wound produced by the insertion of a vascular sheath, cannula, or
catheter in the skin of an animal, which comprises the steps of:
[0056] (i) inserting a purse-string suture within 3 mm of the
percutaneous wound, using a suture needle and a physiologically
suitable suture material, wherein said purse-string suture is
produced through three or four needle passes of monofilament 2.0
polypropylene or nylon, and wherein a final pass of the suture
needle is oriented to bring the final exit site of the suture
material substantially adjacent to an initial entry site of the
suture material through the skin; [0057] (ii) bringing the initial
entry and final exit limbs of the suture material through a tension
collar while said vascular sheath, cannula, or catheter is inserted
through the skin; [0058] (iii) manually tightening the tension
collar, after removal of said vascular sheath, cannula, or
catheter, until hemostasis is achieved; [0059] (iv) applying a
suitable suture lock to the free ends of the suture material to
secure the tension collar; [0060] (v) releasing said suture lock
and loosening said tension collar after a sufficient period of time
for hemostasis; [0061] (vi) optionally retightening said tension
collar and reapplying said suture lock if required to prevent
continued bleeding or oozing of blood; and [0062] (vii) removing
said tension collar, suture lock, and suture material when
satisfactory hemostasis has been achieved.
[0063] The present invention also relates to a kit for producing
hemostasis of a percutaneous wound in an animal, comprising: [0064]
(a) a suture of acceptable size and material characteristics
suitable for the type and location of the percutaneous wound to be
treated; [0065] (b) a suture needle; [0066] (c) a tension collar;
and [0067] (d) a suture-lock.
[0068] In a preferred embodiment, said tension collar and
suture-lock are optionally an integrated single unit.
[0069] In a preferred embodiment, said suture material is a
nonabsorbable monofilament.
[0070] In a most preferred embodiment, said suture material is 2.0
monofilament polypropylene or nylon.
[0071] Finally, the present invention relates to a releasable
hemostasis device comprising: [0072] (i) a body comprising two
hollow shaft portions (1) and (2), each having one or more exterior
wall(s) and an internal channel (3), and a cavity portion (4)
located between said shaft portions; and [0073] (ii) a slide-spring
lock mechanism within said cavity portion for providing a
suture-locking effect within the hemostasis device, said
slide-spring lock mechanism having a plunger (5) mounted slidably
in said passage for movement relative to said cavity portion along
a predetermined axis, and having an end portion (6) which is
accessible from the outside of the cavity portion for manually
pressing the plunger inwardly along said axis from a gripping
position to a released position, said cavity portion having one or
more aperture(s) (7) and said plunger having one or more
aperture(s) (8) through which one or more suture(s) (9) can extend
generally transversely of said axis, wherein said slide-spring lock
mechanism is in sliding engagement with one or more length(s) of
suture material, said slide-spring lock mechanism being capable of
releasable locking engagement along said length(s) of suture
material.
[0074] In a preferred embodiment, said slide-spring lock mechanism
is biased to lock said suture material, and to release said suture
material upon application of sufficient force to place said one or
more aperture(s) in said cavity portion and said plunger in an
essentially coaxial orientation. A preferred biasing device is a
coil spring (10).
[0075] In another preferred embodiment, said body is integrally
formed.
Suture Materials and Suturing Techniques
[0076] A suture is a thread that approximates and maintains tissues
until the natural healing process has provided a sufficient level
of wound strength or compresses blood vessels in order to stop
bleeding.
[0077] Suture Materials. Sutures can be classified into one of two
groups, absorbable and nonabsorbable. Absorbable sutures are, as
the name implies; temporary due to their ability to be "absorbed"
or decomposed by the natural reaction of the body to foreign
substances. An absorbable suture is one that loses its tensile
strength within 60 days. Not all absorbable sutures have the same
resistance level to absorption, but each can be formulated or
treated in order to obtain a desired decomposition rate.
Nonabsorbable sutures are, in like manner, sutures that are not
dissolved or decomposed by the body's natural action. Such sutures
are generally not naturally occurring materials, with the exception
of silk; silk and nylon, while being classified as nonabsorbable,
actually dissolve after a long period of time compared to that of
other absorbable materials.
[0078] Sutures are manufactured with a wide variety of parameters.
They can be monofilament or many filaments twisted together, spun
together, or braided. They can also be dyed, undyed, coated, not
coated.
[0079] Currently, sutures are designed to result in the most
desirable effect for any given situation as determined by those
administering the sutures. Taken into consideration in the
manufacture and use of sutures are properties such as stress-strain
relationship, tensile strength and rate of retention, flexibility,
intrinsic viscosity, wettability, surface morphology, degradation,
thermal properties, contact angle of knots, and elasticity.
[0080] Properties such as stress-strain relationship and tensile
strength have a direct effect on how much force at a given rate the
closure will be able to withstand. For example, a cough would
impose a fast rate of elongation whereas edema or hemorrhage would
impose a slow rate of elongation. Surface morphology, the
description and condition of the outer surface of the suture, has a
direct effect on how the tissue in which the suture is located is
affected when the suture is applied. For example, a braided suture
can cause a type of sawing effect at the insertion points into the
tissue. Flexibility in relation to tensile strength is also of high
priority in suture manufacture. Some materials are braided because
they become too stiff for handling if formed into monofilaments of
sufficient diameter and strength to hold the tissue edges together.
Rate of degradation is important due to the difference of required
periods of time that a suture is needed to maintain its strength
and placement within the tissue. Suture application includes the
knotting or tying off of the suture ends. Knotting causes a severe
decrease of strength in the suture material, thus when there is a
break in the suture, it occurs most frequently at the site of the
knot. Selection of the best suture for a given situation involves
consideration of all of these factors to produce the most efficient
and best suited material.
[0081] Some important suture characteristics include tensile
strength, as related to suture size and as related to weight
required to break a suture; knot strength; force required for a
knot to slip; configuration, either monofilament, which has less
risk of infection, or braided multifilament, which is easier to
handle and tie; elasticity; degree suture stretches and return to
original length; memory or suture stiffness, wherein high memory
correlates to stiffness, difficult handling, and spontaneous
untying; and tissue reactivity, such as the inflammatory response
to the suture. In general, preferred suture characteristics include
good knot security, inertness, adequate tensile strength,
flexibility, ease in handling, nonallergenic nature, resistance to
infection, smooth passage through tissue, and, if appropriate,
absorbability.
[0082] Suture Material-Characteristics.
[0083] Natural, Absorbable: Plain Catgut is prepared from the
submucous coat of sheep or cow intestine. Plain catgut is rapidly
hydrolyzed in tissues and loses its integrity within a few days.
Generally, it should only be used in tissues where this is not a
disadvantage. Catgut has a variable resorption rate, and thus
unpredictable tensile strength, and is associated with greater
tissue reaction than synthetic materials.
[0084] Chromic catgut has been treated with chromic acid salts to
affect cross-binding, which delays hydrolysis. Generally, it should
not be used where absorption progresses before healing is complete
enough to restore adequate tensile strength. Absorption can be
unpredictable, particularly in contaminated or infected wounds.
[0085] Natural, Non-absorbable: Silk is generally presented as a
silicone-coated non-absorbable braid. It has great strength and
suppleness, and handles well with secure knots. It is of little use
for vascular or dermal locations because it may encourage
infection, suture abscesses may leave cosmetically unacceptable
scars, and suture sinuses may harbor infection when silk is used in
deeper layers. Linen and cotton have similar handling properties,
but may be problematic in infected or contaminated wounds.
[0086] Metallic sutures are ideal for use in contaminated or dirty
wounds. Monofilaments or braids are difficult to manage, as any
kinks significantly reduce strength.
[0087] Synthetic, Absorbable: Polyglecaprone 25 (Monocryl),
polydioxanone (PDS), polyglactin-910 (Vicryl), polyglycolic acid
(Dexon), and polycarbonate are braided or monofilament synthetic
polymeric sutures which retains their integrity for a significant
time in tissue. They handle as well as catgut, and knots are
secure, but are degraded by hydrolysis in a slower and more
predictable fashion than catgut. These sutures can also be used for
buried subcuticular skin closure, thereby avoiding the need for
suture removal. There is a risk of minor infection or wound leakage
in contaminated surgery.
[0088] Synthetic, Non-absorbable: Polyamide nylon, polyester
dacron, Polytetrafluoroethylene (PTFE), and polypropylene are not
biodegradable, may be more difficult to tie and need several throws
for knot security, but glide easily through tissues in monofilament
form. Braided synthetics are much easier to handle and are ideal
where risk of infection must be minimized.
[0089] Suture Sizes. The United States Pharmacopoeia (USP) is the
official compendium for the suture industry. It sets standards and
guidelines for suture manufacture. Suture sizes are given by a
number representing diameter ranging in descending order from 10 to
1 and then 1-0 to 12-0, 10 being the largest and 12-0 being the
smallest, at a diameter smaller than a human hair. As sutures were
made smaller due to advancement of suture making equipment, USP ran
out of ordinal numbers. So, the size smaller than 1 is 0. Smaller
than 0 is 00 or 2-0, and so on. For the torso and extremities, 4-0
or 5-0 nonabsorbable sutures, or 3-0 or 4-0 absorbable sutures are
generally used. Table I shows the sizes of various sutures:
TABLE-US-00001 TABLE I relationship between USP suture size and
diameter USP Suture sizes Suture Dia. (mm) 2 0.500-0.599 1
0.400-0.499 0 0.350-0.399 2-0 0.300-0.349 3-0 0.200-0.299 4-0
0.150-0.199 5-0 0.100-0.149 6-0 0.070-0.099 7-0 0.050-0.069 8-0
0.040-0.049 9-0 0.030-0.039 10-0 0.020-0.029
[0090] Suturing Techniques. As a method for closing cutaneous
wounds, the technique of suturing is thousands of years old.
Although suture materials and aspects of the technique have
changed, the goals remain the same: closing dead space, supporting
and strengthening wounds until healing increases their tensile
strength, approximating skin edges for an aesthetically pleasing
and functional result, and minimizing the risks of bleeding and
infection.
[0091] The choice of suture technique depends on the type and
anatomic location of the wound, the thickness of the skin, the
degree of tension, and the desired cosmetic result. The proper
placement of sutures enhances the precise approximation of the
wound edges, which helps minimize and redistribute skin tension.
Wound eversion is essential to maximize the likelihood of good
epidermal approximation. Eversion is desirable to combat the risk
of scar depression secondary to tissue contraction during healing.
The elimination of dead space, the restoration of natural anatomic
contours, and the minimization of suture marks are also important
to optimize the cosmetic and functional results.
[0092] Many varieties of suture material and needles are available
to a surgeon. The choice of sutures and needles is determined by
the location of the lesion, the thickness of the skin in that
location, and the amount of tension exerted on the wound.
Regardless of the specific suture and needle chosen, the basic
techniques of needle holding, needle driving, and knot placement
remain the same.
[0093] The suture needle has 3 sections. The point is the sharpest
portion and is used to penetrate the tissue. The body represents
the mid portion of the needle. The swage is the thickest portion of
the needle and the portion to which the suture material is
attached. In cutaneous surgery, 2 main types of needles are used:
cutting and reverse cutting. Both needles have a triangular body. A
cutting needle has a sharp edge on the inner curve of the needle
that is directed toward the wound edge. A reverse cutting needle
has a sharp edge on the outer curve of the needle that is directed
away from the wound edge, which reduces the risk of the suture
pulling through the tissue. For this reason, the reverse cutting
needle is used more often than the cutting needle in cutaneous
surgery.
[0094] The tissue should be stabilized to allow suture insertion.
Depending on the surgeon's preference, toothed or untoothed forceps
or skin hooks may be used to gently grasp the tissue. Excessive
trauma to the tissue being sutured should be avoided to reduce the
possibility of tissue strangulation and necrosis. Forceps are
necessary for grasping the needle as it exits the tissue after a
pass. Prior to removing the needle holder, grasping and stabilizing
the needle is important. This maneuver decreases the risk of losing
the needle in the dermis or subcutaneous fat, and it is especially
important if small needles are used in areas such as the back,
where large needle bites are necessary for proper tissue
approximation.
[0095] Simple Interrupted Sutures. The most commonly used suture in
cutaneous surgery is the simple interrupted suture. This suture is
placed by inserting the needle perpendicular to the epidermis,
traversing the epidermis and the full thickness of the dermis, and
exiting perpendicular to the epidermis on the opposite side of the
wound. The two sides of the stitch are symmetrically placed in
terms of depth and width. In general, the suture has a flask-shaped
configuration, that is, the stitch is wider at its base (dermal
side) than at its superficial portion (epidermal side). If the
stitch encompasses a greater volume of tissue at the base than at
its apex, the resulting compression at the base forces the tissue
upward and promotes eversion of the wound edges.
[0096] Interrupted sutures are comparatively easy to place, have
greater tensile strength, and have less potential for causing wound
edema and impaired cutaneous circulation. Interrupted sutures also
allow the surgeon to make adjustments as needed to properly align
wound edges as the wound is sutured. Disadvantages of interrupted
sutures include the length of time required for their placement and
the greater risk of crosshatched marks across the suture line. The
risk of crosshatching can be minimized by removing sutures early to
prevent the development of suture tracks.
[0097] Simple running sutures. The simple running suture is an
uninterrupted series of simple interrupted sutures. The suture is
started by placing a simple interrupted stitch, which is tied but
not cut. A series of simple sutures are placed in succession
without tying or cutting the suture material after each pass.
Sutures are evenly spaced, and tension is evenly distributed along
the suture line. The line of stitches is completed by tying a knot
after the last pass at the end of the suture line. The knot is tied
between the tail end of the suture material where it exits the
wound and the loop of the last suture placed.
[0098] Running sutures are useful for long wounds in which wound
tension has been minimized with properly placed deep sutures and in
which approximation of the wound edges is good. This type of suture
may also be used to secure a split- or full-thickness skin graft.
Theoretically, less scarring occurs with running sutures compared
with interrupted sutures because fewer knots are made with simple
running sutures; however, the number of needle insertions remains
the same.
[0099] Advantages of the simple running suture include quicker
placement and more rapid reapproximation of wound edges, compared
with simple interrupted sutures. Disadvantages include possible
crosshatching, the risk of dehiscence if the suture material
ruptures, difficulty in making fine adjustments along the suture
line, and puckering of the suture line when the stitches are placed
in thin skin.
[0100] Running locked sutures. The simple running suture is locked:
the first knot of a running locked suture is tied as in a
traditional running suture and may be locked by passing the needle
through the loop preceding it as each stitch is placed. This suture
is also known as the baseball stitch because of the final
appearance of the running locked suture line.
[0101] Locked sutures have increased tensile strength; therefore,
they are useful in wounds under moderate tension or in those
requiring additional hemostasis because of oozing from the skin
edges. Running locked sutures have an increased risk of impairing
the microcirculation surrounding the wound, and they can cause
tissue strangulation if placed too tightly.
[0102] Vertical mattress sutures. The vertical mattress suture is a
variation of the simple interrupted suture. It consists of a simple
interrupted stitch placed wide and deep into the wound edge and a
second more superficial interrupted stitch placed closer to the
wound edge and in the opposite direction. The width of the stitch
is increased in proportion to the amount of tension on the wound.
That is, the higher the tension, the wider the stitch.
[0103] A vertical mattress suture is especially useful in
maximizing wound eversion, reducing dead space, and minimizing
tension across the wound. One of the disadvantages of this suture
is crosshatching. The risk of crosshatching is greater because of
increased tension across the wound and the four entry and exit
points of the stitch in the skin. Placing each stitch precisely and
taking symmetric bites is especially important with this
suture.
[0104] The half-buried vertical mattress suture is a modification
of the vertical mattress suture and eliminates two of the four
entry points, thereby reducing scarring. The half-buried vertical
mattress suture is placed in the same manner as the vertical
mattress suture, except that the needle penetrates the skin to the
level of the deep part of the dermis on one side of the wound,
takes a bite in the deep part of the dermis on the opposite side of
the wound without exiting the skin, crosses back to the original
side of the wound, and exits the skin. Entry and exit points
therefore are kept on one side of the wound.
[0105] The pulley suture is another modification of the vertical
mattress suture. When pulley sutures are used, a vertical mattress
suture is placed, the knot is left untied, and the suture is looped
through the external loop on the other side of the incision and
pulled across. At this point, the knot is tied. This new loop
functions as a pulley, directing tension away from the other
strands. The pulley suture facilitates greater stretching of the
wound edges and is used when additional wound closure strength is
desired.
[0106] Far-near Near-far Modified Vertical Mattress Sutures.
Another stitch that serves the same function as the pulley suture
is the far-near near-far modification of the vertical mattress
suture. The first loop is placed approximately 4-6 mm from the
wound edge on the far side and approximately 2 mm from the wound
edge on the near side. The suture crosses the suture line and
reenters the skin on the original side at 2 mm from the wound edge
on the near side. The loop is completed, and the suture exits the
skin on the opposite side 4-6 mm away from the wound edge on the
far side. This placement creates a pulley effect.
[0107] The pulley suture is useful when tissue expansion is
desired, and it may be used intraoperatively for this purpose. The
suture is also useful when beginning the closure of a wound that is
under significant tension. By placing pulley stitches first, the
wound edges can be approximated, thereby facilitating the insertion
of buried sutures. When wound closure is complete, the pulley
stitches may be either left in place or removed if wound tension
has been adequately distributed after insertion of the buried and
surface sutures.
[0108] Horizontal Mattress Suture. The horizontal mattress suture
is placed by entering the skin 5 mm to 1 cm from the wound edge.
The suture is passed deep in the dermis to the opposite side of the
suture line and exits the skin equidistant from the wound edge. The
needle reenters the skin on the same side of the suture line 5 mm
to 1 cm lateral of the exit point. The stitch is passed deep to the
opposite side of the wound where it exits the skin and the knot is
tied.
[0109] The horizontal mattress suture is useful for wounds under
high tension because it provides strength and wound eversion. This
suture may also be used as a stay stitch to temporarily approximate
wound edges, allowing insertion of simple interrupted or
subcuticular stitches. The temporary stitches are removed after the
tension is evenly distributed across the wound. In addition to the
risk of suture marks, horizontal sutures have a high risk of tissue
strangulation and wound edge necrosis if tied too tightly. Taking
generous bites, using bolsters, and cinching the suture only as
tightly as necessary to approximate the wound edges may decrease
the risk, as does removing the sutures as early as possible.
Placing sutures at a greater distance from the wound edge
facilitates their removal.
[0110] Half-buried Horizontal Sutures. The half-buried horizontal
suture or tip stitch begins on the side of the wound on which the
flap is to be attached. The suture is passed through the dermis of
the wound edge to the dermis of the flap tip. The needle is passed
laterally in the same dermal plane of the flap tip, exits the flap
tip, and reenters the skin to which the flap is to be attached. The
needle is directed perpendicularly and exits the skin; then, the
knot is tied.
[0111] Buried Horizontal Mattress Suture. The buried horizontal
mattress suture is placed in the mid-to-deep part of the dermis to
prevent the skin from tearing. If tied too tightly, the suture may
strangulate the approximated tissue. The buried horizontal mattress
suture is used to eliminate dead space, reduce the size of a
defect, or reduce tension across wounds.
[0112] Purse-string Suture. In the purse-string suture, a
continuous stitch is placed, paralleling the edges of a wound. The
wound edges are inverted when tied. The purse-string suture is
commonly used to close circular wounds.
[0113] Suture removal. In general, sutures should be removed within
1-2 weeks of their placement, depending on the anatomic location.
Prompt removal reduces the risk of suture marks, infection, and
tissue reaction. However, to prevent dehiscence and spread of the
scar, sutures should not be removed too soon. As a general rule,
the greater the tension across a wound, the longer the sutures
should remain in place. Buried sutures, which are placed with
absorbable suture material, are left in place because they
dissolve.
[0114] Proper suture removal technique is important to maintain
good results after sutures are properly selected and executed.
Sutures should be gently elevated with forceps, and one side of the
suture should be cut. Then, the suture is gently grasped by the
knot and gently pulled toward the wound or suture line until the
suture material is completely removed. If the suture is pulled away
from the suture the wound edges may separate. Steri-Strips may be
applied with a tissue adhesive to provide continued supplemental
wound support after the sutures are removed.
EXAMPLES
[0115] The following examples are illustrative of the present
invention and are not intended to be limitations thereon.
Example 1
Results of Prototype Testing
[0116] The following example illustrates the results obtained
during the use of a prototype of a device of the present invention,
which has been tested in a cohort of 161 patient examples. Outcomes
of all patients at the University of Pennsylvania and the
University of Toronto who undergo this method of dialysis shunt
puncture site closure continue to be followed, including procedural
success rates and duration of placement.
[0117] Data was gathered prospectively with followup via review of
the dialysis records and clinical examination at time of next
intervention for a mean of 4 months (2 weeks to 17 months). Within
the 18 month study period, 161 hemostasis devices were placed in
106 patients, of which 40 were female (38%) and 66 were (62%) male.
The patients ranged in age from 23 to 83 years (mean, 56.4 years).
Hemostasis devices were placed in 106 grafts and 55 fistulae.
[0118] Procedures performed included 17 central vein
angioplasties/stent placements, 45 declotting procedures, and 98
balloon angioplasties for stenoses. The sheath sizes ranged from
5-10 Fr. The most commonly used sheath sizes were 6 Fr. (56
punctures) and 7 Fr. (36 punctures). In 10 instances, 10 Fr.
sheaths were used. In these 10 instances, there were nevertheless
no complications related to application of the hemostasis
device.
[0119] The inventive methods alone were successful in achieving
hemostasis in 140 of 161 placements (87%) in the total of 106
patients. In 8 of 161 instances (5%), the suture was broken during
application, and manual compression was used to achieve hemostasis.
In 11 cases (7%), the patient bled through the suture, and manual
pressure was used to aid hemostasis. In 2 applications (1%),
hemostasis was not obtained prior to patient discharge, and the
purse string suture was tied and the patient discharged, with
removal of the suture in 2-4 days time by a dialysis nurse. There
were no false aneurysms, hematomata or access thromboses that could
be attributed to the use of this technique.
[0120] The invention being thus described, it will be obvious that
the same may be modified or varied in many ways. Such modifications
and variations are not to be regarded as a departure from the
spirit and scope of the invention and all such modifications and
variations are intended to be included within the scope of the
following claims.
* * * * *