U.S. patent application number 13/587779 was filed with the patent office on 2013-02-14 for systems and methods for protecting incisions.
The applicant listed for this patent is Adel Aali, Raymond Barbuto. Invention is credited to Adel Aali, Raymond Barbuto.
Application Number | 20130041337 13/587779 |
Document ID | / |
Family ID | 42829306 |
Filed Date | 2013-02-14 |
United States Patent
Application |
20130041337 |
Kind Code |
A1 |
Aali; Adel ; et al. |
February 14, 2013 |
SYSTEMS AND METHODS FOR PROTECTING INCISIONS
Abstract
The present invention provides systems and methods for
protecting wounds, such as surgical incisions. In one embodiment, a
dressing for protecting a wound includes: a support cushion
configured to surround the wound, the support cushion having
sidewalls defining a major axis and a minor axis, the support
cushion including at least two perforations that traverse the
sidewalls at offset locations; a reservoir configured to be
suspended over and in engagement with the support cushion; and a
cover configured to be positioned over the reservoir. The at least
two perforations may define first and second interlocking J-shaped
portions. The support cushion may include a wicking portion
configured to surround the wound and a hydrophobic portion
configured to surround the hydrophobic portion. The wicking portion
may be configured to transfer fluid from the wound to the
reservoir. Methods of applying the dressing, and kits including the
dressing, also are provided.
Inventors: |
Aali; Adel; (Irvine, CA)
; Barbuto; Raymond; (Dagsboro, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Aali; Adel
Barbuto; Raymond |
Irvine
Dagsboro |
CA
DE |
US
US |
|
|
Family ID: |
42829306 |
Appl. No.: |
13/587779 |
Filed: |
August 16, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12504590 |
Jul 16, 2009 |
8252971 |
|
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13587779 |
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Current U.S.
Class: |
604/385.01 |
Current CPC
Class: |
A61F 2013/00455
20130101; A61F 2013/00655 20130101; A61F 2013/00561 20130101; A61F
13/00072 20130101; A61F 2013/00251 20130101; A61F 2013/00565
20130101; A61F 2013/0057 20130101; A61F 2013/00323 20130101; A61F
2013/00153 20130101; A61F 2013/00834 20130101; A61F 2013/00825
20130101; A61F 2013/00782 20130101; A61F 2013/00812 20130101; A61F
2013/00319 20130101; A61F 13/00068 20130101; A61F 15/008 20130101;
A61F 2013/00557 20130101; A61F 2013/00285 20130101; A61F 2013/0017
20130101; A61F 2013/00165 20130101; A61F 13/022 20130101; A61F
2013/00536 20130101; A61F 13/0226 20130101 |
Class at
Publication: |
604/385.01 |
International
Class: |
A61F 13/45 20060101
A61F013/45 |
Claims
1. A dressing for protecting a wound, the dressing comprising: a
support cushion configured to surround the wound, the support
cushion having sidewalls defining a major axis and a minor axis,
the support cushion including at least two perforations that
traverse the sidewalls at offset locations; a reservoir configured
to be suspended over and in engagement with the support cushion;
and a cover configured to be positioned over the reservoir.
2. The dressing of claim 1 wherein the at least two perforations
define first and second interlocking J-shaped portions.
3. The dressing of claim 1 wherein the support cushion comprises a
hydrophobic portion and a wicking portion, the wicking portion
being configured to surround the wound and the hydrophobic portion
being configured to surround the wicking portion.
4. The dressing of claim 3 wherein the wicking portion is
configured to transfer fluid from the wound to the reservoir.
5. The dressing of claim 3, wherein the cover is configured to
retain the reservoir in engagement with the wicking portion.
6. The dressing of claim 3, wherein the wicking portion defines a
flange of the support cushion, the flange having a ledge to accept
a portion of the reservoir.
7. The dressing of claim 1, wherein the support cushion includes
additional perforations that enable removal of selected portions of
the support cushion along the major axis to reduce a length of the
support cushion along the major axis.
8. The dressing of claim 1, wherein the support cushion includes
additional perforations that enable removal of selected portions of
the support cushion along the minor axis to reduce a width of the
support cushion along the minor axis.
9. The dressing of claim 1, wherein at least a portion of each of
the at least two perforations is curved.
10. The dressing of claim 1, further comprising a plurality of
perforations defined in the reservoir to enable removal of selected
portions of the reservoir.
11. The dressing of claim 1, wherein the support cushion further
comprises a hydrophobic barrier.
12. The dressing of claim 1, further comprising a biocompatible
adhesive for securing the support cushion around the wound.
13. The dressing of claim 1, wherein the reservoir comprises a
first hydrophilic layer, a non-stretchable mesh or scrim, and a
second hydrophilic layer.
14. The dressing of claim 1, wherein the cover comprises a
breathable material.
15. The dressing of claim 14, wherein a vent is defined in the
reservoir, the vent permitting humidity over the wound to escape
through the vent and the cover.
16. The dressing of claim 1, further comprising a biocompatible
adhesive securing the cover to the reservoir.
17. The dressing of claim 1, further comprising a biocompatible
adhesive for securing the cover to the support cushion.
18. The dressing of claim 1, further comprising means for
repeatedly attaching and detaching the cover to the support cushion
so that the wound is viewable without entirely removing the
dressing.
19. A method for protecting a wound, the method comprising:
providing a support cushion configured to surround the wound, the
support cushion having sidewalls defining a major axis and a minor
axis, the support cushion including at least two perforations that
traverse the sidewalls at offset locations; surrounding the wound
with a support cushion; applying a reservoir over the support
cushion; and transferring fluid from the wound to the
reservoir.
20. The method of claim 19, wherein a plurality of additional
perforations are defined in the support cushion, the method further
comprising reducing a size of the support cushion along the major
axis by removing selected portions of the support cushion.
21. The method of claim 19, wherein the reservoir includes a
plurality of perforations, the method further comprising reducing a
size of the reservoir by removing a selected portion of the
reservoir along at least one perforation of the plurality of
perforations defined in the reservoir.
22. The method of claim 19, wherein the support cushion includes a
stepped profile that defines a ledge and a recess, the method
further comprising fitting the reservoir within the recess so that
the reservoir engages the ledge and is suspended over the
wound.
23. The method of claim 22, wherein the support cushion comprises a
hydrophobic portion that defines the recess and a hydrophilic
portion that defines the ledge.
24. The method of claim 19, further comprising securing a cover to
the support cushion with a biocompatible adhesive.
25. A kit for a dressing for use in protecting a wound, the kit
comprising: a support cushion configured to surround the wound, the
support cushion having sidewalls defining a major axis and a minor
axis, the support cushion including at least two perforations that
traverse the sidewalls at offset locations; a reservoir configured
to be applied over the support cushion; a backing upon which the
support cushion and reservoir are mounted; and instructions for use
printed on the backing, the instructions for use describing steps
for assembling the dressing.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation under 35 U.S.C. .sctn.120
of U.S. patent application Ser. No. 12/504,590, filed Jul. 16, 2009
and entitled "Systems and Methods for Protecting Incisions," the
entire contents of which are incorporated by reference herein.
FIELD OF THE INVENTION
[0002] This application generally relates to systems and methods
for protecting wounds, particularly incisions.
BACKGROUND OF THE INVENTION
[0003] Wounds occur when the integrity of tissue is compromised,
affecting one or more layers of the epidermis or underlying tissue.
There are several types of wounds, including acute, chronic, and
iatrogenic wounds. Acute wounds may be caused by an initiating
event, such as a accident-related injury, surgical procedure or by
operation of an infectious disease. Acute wounds caused by
accident-related injuries generally take the form of punctures,
abrasions, cuts, lacerations, or burns. Acute wounds caused by
surgical procedures may be in the form of incisions caused by
cutting into or through the skin using a scalpel or other sharp
instrument. For example, depending on the procedure, an incision
may extend through some or all of the layers of the skin, e.g.,
through the epidermis, dermis and subcutis, as well as into or
through muscle, bone, ligaments, and/or internal organs as needed
for the surgeon to be able to access the body part to be treated.
Chronic wounds are wounds that generally do not heal within three
months, due to one or more of: ischemia of the vessels supplying
the tissue, venous hypertension or compromise of the immune
response, such as observed, for example, with venous ulcers,
diabetic ulcers and pressure ulcers. Depending on etiology, such as
diabetes, venous insufficiency, or cardiovascular failures, acute
wounds may become recalcitrant and even chronic. Iatrogenic wounds
are wounds that were initially acute and caused by surgical
incision, but become infected.
[0004] There are three general classes of wound treatment
techniques, commonly referred to as "primary intention," "secondary
intention," and "tertiary intention." Primary intention may be used
to treat acute wounds that are clean, uninfected, and involve
little tissue loss, such as surgical incisions. In a primary
intention technique, the edges of the wound are brought together
and secured, e.g., using sutures, staples, or adhesive strips. Such
wounds have a relatively low risk of infection.
[0005] Secondary intention may be used to treat acute or chronic
wounds in which there may be sufficient loss of tissue and/or of
structural integrity, which may have been caused by tissue necrosis
or excision, that primary intention would be inappropriate, e.g.,
that the skin would need to be stretched too far to safely close
the wound with sutures or adhesive. In a secondary intention
technique, the wound is left open and allowed to close on its own
by the reparative process. Exudate may be allowed to drain freely,
and granulation tissue allowed to fill the cavity of the wound.
Such wounds have a relatively high risk of infection because they
may be exposed to the environment and may be slow to heal.
[0006] Tertiary intention, which is sometimes also referred to as
"delayed primary closure," may be appropriate to treat acute wounds
that are infected or otherwise experiencing complications, e.g.,
iatrogenic wounds. In a tertiary intention technique, the wound is
often left open for a period of time to allow the complication to
at least partially resolve, and then closed using primary
intention, e.g., sutures, staples, or adhesive. For example,
temporarily leaving such a wound open may allow edema (swelling) or
infection to resolve, exudate to drain from the wound, the wound
edges to contract, and/or granulation tissue to form. Such wounds
may be associated with a high risk of infection and a large loss of
tissue.
[0007] Conventional wound treatment also typically involves
covering the wound with a dressing to prevent further contamination
and infection, to retain moisture, and to absorb fluids such as
blood or exudate. While exudate contains biochemical compounds that
benefit wound healing, excessive exudate in the wound or in the
region surrounding the wound, called the "periwound region," may
facilitate degradation of tissue and/or serve as a growth medium
for bacteria. For patients with acute wounds and otherwise healthy
skin, the presence of excess fluid such as exudate is not a
significant concern. However, for patients with chronic wounds, the
presence of excess fluid, particularly excess exudate, may delay
healing and further damage the skin in the periwound region.
[0008] Conventional wound dressings also typically do not address
the pain created by the wound treatment system, particularly where
the wound treatment system continuously contacts the wound. For
example, gauze, which is applied directly onto a wound, is capable
of absorbing only a limited amount of exudate, and readily
transports excess exudate onto the periwound region, which may
cause maceration and damage. Moreover, gauze typically is placed in
direct contact with, and adheres to the wound bed, so that normal
motion of the patient results in rubbing, itching and discomfort.
In addition, removal of the gauze at periodic intervals may be
painful and may disrupt at least some of the healing that may have
occurred.
[0009] Wounds covered with conventional dressings, such as gauze,
are also vulnerable to "dehiscence," or unintentional reopening of
the wound. Dehiscence may be caused by physical trauma to the wound
and/or by poor wound healing. For example, an incision treated
using primary intention, e.g., that is sutured and covered with
gauze, may inadvertently be opened if skin on one side of the
incision is pulled away from skin on the other side of the
incision. Although the sutures may resist such lateral forces, the
wound may at least partially open, disrupting some of the healing
that may have occurred. The skin may also tear in the vicinity of
the sutures, depending on the magnitude of the force. Wounds
treated by secondary or tertiary intention may be at least as
vulnerable to dehiscence as those treated by primary intention,
because they not only lack sutures for resisting such lateral
forces, but also may have worse structural integrity because of
poor skin health in the region of the wound. Poor wound healing
also can increase the risk of dehiscence. For example, patients
with poor circulation, e.g., diabetics, may have low blood supply
in certain parts of their body which may delay wound healing. Some
patients may have genetic disorders, diseases, or may take
medications that suppress the formation of collagen and/or other
tissues needed for healing. Additionally, the longer it takes a
wound to heal, the longer the time over which the wound is
vulnerable to reopening by physical trauma, which can further delay
healing.
[0010] Conventional dressings, such as gauze, do not adequately
resist lateral physical forces that may cause wound dehiscence, and
do not adequately manage fluid that may drain from the wound, among
other shortcomings. For example, U.S. Pat. No. 5,060,662 to
Farnsworth discloses a bandage including a ring of pliant material,
such as a flexible foam, which is disclosed as holding the rest of
the bandage out of contact with the wound. Farnsworth discloses
that the bandage further includes an air permeable member,
fabricated of a material such as nylon gauze, which is affixed to
the upper side of the ring; and an outer protective layer, having a
plurality of relatively large openings, which is affixed to the air
permeable member. Although Farnsworth discloses that the ring, air
permeable layer, and protective layer are formed with lines of
perforations permitting the bandage to be separated into sections
for application to wounds of different sizes, the separate pieces
do not interlock with one another when applied around the wound.
The separate pieces are therefore susceptible to being separated by
lateral forces and, as such, would not adequately resist those
lateral forces to protect the wound from dehiscence.
[0011] U.S. Pat. No. 6,570,050 to Augustine et al. discloses a
bandage for autolytic wound debridement that includes a
fluid-impermeable enclosure including a fluid-absorbent material
that is positioned to receive and retain exuded fluid that
originates in the wound. Augustine discloses that when the
enclosure is attached to the skin it creates a closed chamber over
the wound, that maintains a near-100% humid atmosphere about the
wound. Augustine teaches that such high humidity is desirable, but
failed to recognize that collecting exuded fluid in such a chamber
may macerate and damage the skin under the chamber. Moreover, the
fluid-impermeable enclosure may create a ring of pressure where it
contacts the skin, which may not only damage that skin but may
actually enhance dehiscence of the wound. Additionally, the bandage
of Augustine is not adjustable, and so can only be used with wounds
having a narrow range of sizes.
[0012] U.S. Pat. No. 7,193,454 to Rosenberg discloses an occlusive
dressing system that includes an endless, elongated, flexible,
adhesive barrier adapted to be arranged around a wound, and an
impermeable sealing film adapted to overlie the barrier and to seal
the wound from the environment. Like Augustine, Rosenberg failed to
recognize that such a sealed environment may macerate and damage
the skin. Additionally, the flexible barrier would provide little
resistance to lateral forces, and thus little protection against
wound dehiscence, and the impermeable sealing film would not
cushion the wound against forces applied from above the wound.
[0013] Thus, what is needed is a dressing that resists lateral
physical forces that may cause wound dehiscence, that cushions the
wound, and manages fluid that may drain from the wound, among other
shortcomings.
SUMMARY OF THE INVENTION
[0014] The present invention provides systems and methods for
protecting wounds such as incisions by resisting lateral forces
that may cause dehiscence, by cushioning the wounds from external
pressure sources, and absorbing exudate or other fluids from the
wounds. The dressings of the present invention may be used to
protect a wide range of acute, chronic, and infected wounds,
including surgical incisions. For example, dressings constructed in
accordance with the present invention may be advantageously used to
protect surgical areas where skin is most vulnerable, such as
split-thickness graft sites and cosmetic surgeries.
[0015] Dressings constructed in accordance with the present
invention also may advantageously be used to protect acute wounds
from further trauma, such as may occur in industrial accidents and
in the battle field settings. In particular, dressings in
accordance with the present invention may be applied to reduce
contact pressure on the wound bed. In a battlefield setting, for
example, this aspect of the invention may be particularly valuable,
since a bandaged wound may still have debris or shrapnel in it, and
the dressing can be applied to prevent such contaminants from being
pushed further into the wound during evacuation of the wounded
subject.
[0016] In accordance with one aspect of the present invention, a
dressing for protecting a wound includes: a support cushion
configured to surround the wound, the support cushion having
sidewalls defining a major axis and a minor axis, the support
cushion including at least two perforations that traverse the
sidewalls at offset locations; a reservoir configured to be
suspended over and in engagement with the support cushion; and a
cover configured to be positioned over the reservoir.
[0017] The at least two perforations may define first and second
interlocking J-shaped portions. The support cushion may comprise a
hydrophobic portion and a wicking portion, the wicking portion
being configured to surround the wound and the hydrophobic portion
being configured to surround the wicking portion. The wicking
portion may be configured to transfer fluid from the wound to the
reservoir. The cover may be configured to retain the reservoir in
engagement with the wicking portion. The wicking portion may define
a flange of the support cushion, the flange having a ledge to
accept a portion of the reservoir.
[0018] The support cushion may include additional perforations that
enable removal of selected portions of the support cushion along
the major axis to reduce a length of the support cushion along the
major axis. The support cushion may include additional perforations
that enable removal of selected portions of the support cushion
along the minor axis to reduce a width of the support cushion along
the minor axis. At least a portion of each of the at least two
perforations is curved. There may be a plurality of perforations
defined in the reservoir to enable removal of selected portions of
the reservoir. The support cushion may further comprise a
hydrophobic barrier. The dressing may further comprise a
biocompatible adhesive for securing the support cushion around the
wound. The reservoir may comprise a first hydrophilic layer, a
non-stretchable mesh or scrim, and a second hydrophilic layer. The
cover may comprise a breathable material. A vent may be defined in
the reservoir, the vent permitting humidity over the wound to
escape through the cover. A biocompatible adhesive may secure the
cover to the reservoir. A biocompatible adhesive may secure the
cover to the support cushion. Some embodiments include means for
repeatedly attaching and detaching the cover to the support cushion
so that the wound is viewable without entirely removing the
dressing.
[0019] Under another aspect, a method for protecting a wound
includes: providing a support cushion configured to surround the
wound, the support cushion having sidewalls defining a major axis
and a minor axis, the support cushion including at least two
perforations that traverse the sidewalls at offset locations;
surrounding the wound with a support cushion; applying a reservoir
over the support cushion; and transferring fluid from the wound to
the reservoir.
[0020] In some embodiments, a plurality of additional perforations
may be defined in the support cushion, the method further
comprising reducing a size of the support cushion along the major
axis by removing selected portions of the support cushion. The
reservoir may include a plurality of perforations, the method
further comprising reducing a size of the reservoir by removing a
selected portion of the reservoir along at least one perforation of
the plurality of perforations defined in the reservoir. The support
cushion may include a stepped profile that defines a ledge and a
recess, the method further comprising fitting the reservoir within
the recess so that the reservoir engages the ledge and is suspended
over the wound. The support cushion may comprise a hydrophobic
portion that defines the recess and a hydrophilic portion that
defines the ledge. The method may further include securing a cover
to the support cushion with a biocompatible adhesive.
[0021] Under another aspect, a kit for a dressing for use in
protecting a wound includes: a support cushion configured to
surround the wound, the support cushion having sidewalls defining a
major axis and a minor axis, the support cushion including at least
two perforations that traverse the sidewalls at offset locations; a
reservoir configured to be applied over the support cushion; a
backing upon which the support cushion and reservoir are mounted;
and instructions for use printed on the backing, the instructions
for use describing steps for assembling the dressing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIGS. 1A and 1B are an exploded view and a cross-sectional
view, respectively, of an exemplary dressing of the present
invention.
[0023] FIG. 2 illustrates steps in accordance with one method for
protecting incisions.
[0024] FIG. 3A schematically illustrates a plan view of the
embodiment of the support cushion illustrated in FIGS. 1A-1B.
[0025] FIG. 3B schematically illustrates a cross-sectional view of
an alternative embodiment of the support cushion.
[0026] FIG. 3C schematically illustrates a cross-sectional view of
another alternative embodiment of the support cushion.
[0027] FIG. 3D schematically illustrates a plan view of another
alternative embodiment of the support cushion.
[0028] FIG. 4 schematically illustrates a plan view of a reservoir,
cover, and optional vent according to some embodiments of the
invention.
[0029] FIG. 5A schematically illustrates a plan view of a kit
containing a system for incision protection, according to some
embodiments of the invention.
[0030] FIG. 5B schematically illustrates a plan view of an
alternative kit containing a system for incision protection,
according to some embodiments of the invention.
[0031] FIG. 6A schematically illustrates a plan view of another
alternative embodiment of the support cushion.
[0032] FIG. 6B schematically illustrates a plan view of an
alternative embodiment of a reservoir, cover, and optional vent,
according to some embodiments of the invention.
[0033] FIG. 7 schematically illustrates a plan view of yet another
alternative embodiment of a support cushion and a reservoir, cover,
and optional vent for use with that support cushion, according to
some embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The present invention provides systems and methods for
protecting wounds, such as incisions. Among other things, the
systems and methods provide a wound dressing that cushions the
wound and also resists lateral forces, thus reducing the risk of
wound dehiscence, particularly for wounds being treated using
primary or tertiary intention. The dressing further transfers fluid
away from the wound and into a reservoir that is suspended over,
and not in continuous contact with, the wound. This arrangement
promotes wound healing by reducing the disruption of the wound bed
(and pain) caused by dehiscence and/or by periodic replacement of
conventional dressings, such as gauze, which adhere to the wound
bed.
[0035] An overview of an exemplary embodiment of a system for wound
protection constructed in accordance with the principles of the
present invention is first described, as well as a method of
applying and using that system. Further details on the individual
components employed in the system of the present invention, and
alternative embodiments and methods, are described.
[0036] Overview of System
[0037] Referring now to FIGS. 1A and 1B, an exemplary embodiment of
wound dressing 10, constructed in accordance with the principles of
the present invention to provide wound protection, is described. In
this exemplary embodiment, dressing 10 comprises two discrete
components that are assembled and applied by the patient, nurse,
clinician or other caregiver over wound W in patient's epidermis E.
In the illustrated embodiment, wound W is secured closed using
sutures S; that is, wound W is being treated with primary
intention. However, it should be understood that the dressing can
be applied to any type of wound, e.g., a wound being treated with
primary, secondary, or tertiary intention.
[0038] Dressing 10 includes support cushion 20 and reservoir 40,
which is preferably pre-attached to cover 50. Preferably,
components 20, 40 and 50 of dressing 10 are sized for use with one
another and are enclosed in a sterile package with suitable
instructions to enable the patient or caregiver to quickly and
accurately apply the dressing. Alternatively, because for some
embodiments certain components of dressing 10, such as reservoir
40, may be replaced on a frequent basis than other portions of the
dressing, such components may be individually packaged.
[0039] Support cushion 20 is designed to surround wound W and a
surrounding region of epidermis E extending from the wound margin,
to protect the wound and elevate reservoir 40 and cover 50 above
the wound bed. In the exemplary embodiment of FIGS. 1A-1B, support
cushion 20 includes sidewalls 30 defining a major axis and a minor
axis. Additionally, as described in greater detail below, support
cushion 20 and/or reservoir 40 are optionally constructed to
include perforations P, P' enabling the sizes of these components
to be adjusted to provide a better fit around a particular wound.
For example, support cushion 20 optionally includes at least two
perforations P that traverse the sidewalls 30 at offset locations.
The perforations P defined in support cushion 20 may define first
and second interlocking J-shaped portions of the sidewalls 30, and
additionally may enable removal of selected portions of the support
cushion along the major axis to reduce a length of the support
cushion 20 along the major axis. Similarly, the perforations P'
defined in reservoir 40 may enable removal of selected portions of
the reservoir along the major axis to reduce a length of the
reservoir along the major axis. Other possible configurations for
the support cushion 20, reservoir 40, and perforations P, P' are
provided further below.
[0040] In the illustrated embodiment, hydrophobic portion 22, which
is preferably formed from a hydrophobic closed cell polyolefin
foam, defines sidewalls 30. Support cushion may also include a
wicking portion 23, preferably formed from a hydrophilic open-cell
polyurethane foam. The wicking portion 23 may be configured to
surround the wound W and the hydrophobic portion 22 may be
configured to surround the wicking portion 23. The wicking portion
23 defines a flange, the upper surface 28 of which includes a ledge
that accepts a portion of reservoir 40 and thereby supports
reservoir 40, as depicted in FIG. 1B. Additionally, in the
illustrated embodiment, support cushion 20 includes a hydrophobic
barrier 21, preferably formed from a closed-cell polyurethane foam,
under the hydrophobic portion 22 and the wicking portion 23.
Hydrophobic barrier 21 inhibits seepage of fluid out of the support
cushion 20 onto epidermis E. Lower surface 24 of support cushion 20
includes layer 25 of biocompatible adhesive, which preferably is
hydrophobic and breathable, to secure the support cushion 20 to the
epidermis E. Upper surface 26 of support cushion includes layer 27
of adhesive or a portion of a reusable fastening system, e.g., the
pile of a hook and pile fastening system, such as Velcro, to secure
cover 50 to the upper surface 26 of support cushion 20. Use of a
non-permanent adhesive or a reusable fastening system for layer 27
permits the cover 50 to be periodically removed to inspect the
wound, to apply topical medications or other substances to the
wound, e.g., moisturizing ointments, growth factors, nutrients,
and/or antibiotics, or to replace reservoir 40. In other
embodiments, cover 50 and/or reservoir 40 are left in place over
the wound while dressing 10 is applied to the patient. Support
cushion 20 includes opening 29 that exposes a portion of the
epidermis E surrounding wound W.
[0041] Still referring to FIG. 1, reservoir 40 preferably includes
a sandwich of different density open cell polyurethane foams 41 and
43 joined to mesh or scrim 42, in which the foams 41 and 43 are
selected to absorb fluid from wicking portion 23 and to sequester
the fluid away from the wound bed. In the embodiment depicted in
FIG. 1, reservoir 40 is fastened to the underside of cover 50, and
is sized so that the outer edges of the reservoir are supported on
ledge 28 of wicking portion 23, while the more central regions of
the reservoir are suspended over the wound W and surrounding
epidermis, thus inhibiting contact between reservoir 40 and wound W
and limiting the extent to which force applied to cover 50 and
reservoir 40 is transmitted to wicking portion 23. During use,
wicking portion 23 transfers fluid from the wound W into reservoir
40. Preferably, reservoir 40 fits snugly against the sidewall
defined by hydrophobic portion 22, so as to inhibit leakage of
fluid in the reservoir out of the lateral face of the reservoir.
Optionally, a layer of adhesive may be disposed on the lower
surface of the reservoir 40 that engages ledge 28 of wicking
portion 23 to removably secure those components together. Reservoir
40 preferably includes one or more vents 45 that assist in
modulating the humidity within the dressing through cover 50. In
some embodiments, a plurality of perforations P' are optionally
defined in reservoir 40, along which a caregiver may tear reservoir
40 to resize the reservoir so as to better fit support cushion 20,
which itself also may optionally be resized, as described
herein.
[0042] Cover 50, preferably a breathable material, such as
breathable foam or cloth, overlays reservoir 40. Layer 51 of
adhesive preferably is used to removably secure reservoir 40 to
cover 50. Alternatively, reservoir 40 may be removably fastened to
cover 50 using a removable fastening system, such as hook and pile
arrangement, or a repositionable adhesive. The cover 50 may retain
reservoir 40 in engagement with wicking portion 23.
[0043] As described in greater detail below, the components of
dressing 10 may each be provided with one or more non-stick liners
to facilitate handling of the different components of the system,
e.g., while placing support cushion 20 on epidermis E and/or while
placing reservoir 40 on support cushion 20. The liners may be
removed as appropriate to expose the adhesive layers and secure
components to epidermis E or to each other.
[0044] Multiple features of dressing 10 both protect and enhance
the healing of wound W. First, support cushion 20 is constructed to
reduce or eliminate lateral forces applied to the surrounding
epidermis that otherwise may cause dehiscence of the wound. For
example, the support cushion 20 may be constructed of a high
density foam of sufficient thickness to provides a rigid surround
that protects the wound both from lateral and vertical forces,
e.g., forces that would otherwise potentially cause wound
dehesience by pulling the edges of the wound away from each other.
Moreover, the optional perforations P may define support cushion 20
into two interlocking "J"-shaped portions that prevent or inhibit
the wound from being pulled apart. The lateral offset of the
junctions between the two J-shapes further enhances the support
cushion's resistance to lateral forces.
[0045] Additionally, in some embodiments, additional optional
perforations P allow specific portions of support cushion 20 to be
removed, thus enabling a caregiver to adjust support cushion 20 to
better fit around a particular wound. The shape and locations of
perforations P preferably are configured to maintain the support
cushion's resistance to lateral forces. For example, as illustrated
in FIG. 3A, perforations P may be defined in support cushion 20
such that a portion of the perforations are laterally curved, e.g.,
the portions of the perforations extending through hydrophobic
portion 22. If a caregiver removes sections 31 and 32 of support
cushion 20 by tearing support cushion along the perforations P that
bound those sections, then the remaining portions of support
cushion will fit together along the curves defined by such removal
and interlock with one another, resulting in the support cushion
having a lateral strength comparable to its strength before the
sections were removed. In other embodiments, the perforations P may
be straight, or may be shaped, e.g., in the form of grooves,
zig-zags, "U" shapes, or the like. For example, the perforations P
may be angled, square, triangular, curved, or free form. The
perforations P may define ends that interlock with one another to
resist lateral separation from one another along the major and/or
minor axes.
[0046] In the embodiment illustrated in FIG. 3A, optional
perforations P are arranged as inverted mirror images of each other
about the center of support cushion 20. Thus, if a caregiver
removes sections 31 and 32 of support cushion 20 by tearing it
along the perforations P bounding those sections, then support
cushion 20 becomes separated into two "J"-shaped sections that may
be rejoined and interlocked on epidermis E. In such embodiments,
the offset of the junctions between the "J" helps to protect the
wound from lateral forces, thus inhibiting dehiscence of the wound.
Alternatively, perforations P may be arranged as mirror images of
each other about the center of support cushion 20, e.g., a
caregiver's removal of sections of support cushion 20 separates the
support cushion into two "U"-shaped portions that may be rejoined
and interlocked on epidermis E. Other configurations are possible,
as described below.
[0047] Additionally, although reservoir 40 is arranged to protect
the wound W from the environment and to absorb fluid, it is
suspended over and thus is not in continuous contact with the
wound. This feature may both reduce any pain experienced by the
patient and promote healing. For example, initially placing
reservoir 40 (and the other components of dressing 10) does not
require touching the wound bed itself, resulting in significantly
less pain than, for example, conventional dressings in which gauze
is placed onto the wound. Support cushion and/or reservoir 40 also
readily may be removed without disrupting re-epithelialization of
the wound. Moreover, because reservoir 40 sequesters fluid from the
wound, when reservoir 40 is removed to observe the wound, the fluid
does not flow onto the adhesive used to secure cover 50 to support
cushion 20. This arrangement allows reservoir 40 and cover 50 to be
repositioned and re-secured to support cushion 20, without having
to replace the entire dressing. By contrast, removing previously
known dressings (which contact the wound) often disrupts
re-epithelialization, and fluid within the dressing will flow onto
the adhesive, requiring the entire dressing to be discarded and a
new one applied. Alternatively, if reservoir 40 is saturated with
fluid or if the caregiver identifies another reason to replace the
reservoir, reservoir 40 and cover 50 may be replaced without having
to remove the support cushion 20, thus reducing or avoiding trauma
to the wound potentially associated with removal of support cushion
20.
[0048] It is noted that although reservoir 40 is designed to be
suspended over, rather than in contact with the wound, occasions
may arise where the reservoir will contact the wound. For example,
if sufficient pressure is applied directly onto cover 50 and
reservoir 40, the reservoir may deflect sufficiently to contact the
wound for as long as that pressure is applied. Such temporary
contact is not believed to significantly impede the healing of the
wound, and the diameter and resiliency of support cushion 20
preferably are selected to provide adequate support for cover 50
and reservoir 40 in the expected range of applications.
[0049] Overview of Method
[0050] FIG. 2 illustrates steps in a method 60 of using dressing 10
for managing exudate from a wound, according to some embodiments of
the invention. Typically, the method is implemented by a physician,
nurse, or other caregiver. However, the method is relatively simple
to employ, and the patient himself or herself may apply dressing
10.
[0051] First, at step 61, the caregiver obtains support cushion 20,
reservoir 40, and cover 50, e.g., a kit as described below with
respect to FIGS. 5A-5B. Next, in step 62, the caregiver optionally
adjusts the size of support cushion 20 and reservoir 40 to more
closely circumscribe the wound. For example, as described in
greater detail below, support cushion 20 and reservoir 40
optionally include perforations P, P' allowing the caregiver to
remove selected portions of the respective component. Next, in step
63, support cushion 20 is applied to the epidermis of a patient, so
that the support cushion surrounds the wound and a region of the
epidermis surrounding the wound. In some embodiments, the wicking
portion 23 surrounds the wound, and the hydrophobic portion 22
surrounds the wicking portion. In one example, a non-stick liner
covering lower surface 24 of support cushion 20 may be removed to
expose the adhesive on its lower surface. The support cushion then
is roughly centered around the wound, and pressed onto the
patient's epidermis using gentle manual pressure. A non-stick liner
covering layer 27 on the upper surface of support cushion 20 may be
left in place until a later step, described below.
[0052] At step 64, reservoir 40 and cover 50 (which is preferably
pre-adhered to reservoir 40) then are applied over support cushion
20. For example, the non-stick liner may be removed from layer 27
disposed on the upper surface 26 of hydrophobic portion 22, and
reservoir 40 inserted into support cushion 20 so that the exposed
adhesive on support cushion 20 adheres to cover 50, as illustrated
in FIG. 1B. Alternatively, layer 27 may be disposed on the lower
surface of cover 50 and covered with a non-stick liner that may be
removed so that the exposed adhesive on cover 50 adheres to the
upper surface 26 of hydrophobic portion 22.
[0053] At step 65, fluid is transferred from the wound to the
reservoir, e.g., via wicking portion 23.
[0054] Optionally, a medication or other substance may be applied
to the wound or surrounding epidermis during any appropriate step
in method 60. For example, the wound and epidermis may be cleaned,
dried, and/or debrided or moisturized before applying support
cushion 20 to the epidermis. Or, for example, medications, such as
time-release topical medications, or special dressings, may be
applied.
[0055] Further details of the construction of the individual
components of dressing 10, and alternative embodiments, are now
provided.
[0056] Support Cushion 20
[0057] Referring to FIG. 3A, a first embodiment of support cushion
20 is further described. Support cushion 20 includes sidewalls 30
defining a major axis and a minor axis, and optionally including at
least two perforations P that traverse the sidewalls 30 at offset
locations. The perforations P separate the support cushion 20 into
first and second interlocking portions, e.g., "J"-shaped portions.
In the illustrated embodiment, hydrophobic portion 22 define
sidewalls 30; wicking portion 23 defines a flange, the upper
surface 28 of which defines a ledge that contacts a portion of
reservoir 40; and hydrophobic portion 22 and wicking portion 23 are
secured to hydrophobic barrier 24 (not visible in FIG. 3A). Support
cushion 20 preferably is secured to patient's epidermis using a
biocompatible adhesive layer (also not visible in FIG. 3A), which
is preferably hydrophobic but breathable. Alternatively, or
additionally, support cushion 20 may be secured to the patient's
epidermis using a covering material, such as gauze.
[0058] In some embodiments, support cushion 20 is of unitary
construction, with hydrophobic portion 22, wicking portion 23, and
hydrophobic barrier 24 all being formed from different portions of
the same piece of material, which portions may be differently
treated to modify their hydrophobicity/hydrophilicity as
appropriate. Alternatively, one or more of hydrophobic portion 22,
wicking portion 23, and hydrophobic barrier 24 may be individually
constructed and then heat-fused or otherwise bonded together, e.g.,
using adhesive, thus allowing the materials, thicknesses, and other
characteristics of hydrophobic portion 22, wicking portion 23, and
hydrophobic barrier 24 to be tailored for specific applications.
For example, it may be preferable to form hydrophobic portion 22
using a relatively thick layer of a large-cell hydrophobic
material, to form wicking portion 23 using a relatively thin layer
of a small-cell hydrophobic material, and to form hydrophobic
barrier 24 using a relatively thin layer of large-cell hydrophobic
material. Such a combination of materials and thicknesses imparts
support cushion 20 with sufficient flexibility to be conformable to
substantially any body part, e.g., an arm, leg, neck, or torso,
while maintaining a sufficient level of hydrophobicity to prevent
fluids from leaking out of the support cushion and onto the
epidermis.
[0059] Examples of suitable hydrophobic materials for use in
hydrophobic portion 22 and hydrophobic barrier 24 include
polyolefins, foams (for example, polyethylene foams), and
silicone-based materials, in open cell, closed cell, large cell, or
small cell forms. In still other embodiments (not illustrated),
hydrophobic portion 22 and/or hydrophobic barrier 24 may be
configured as an annular structure filled with a fluid, e.g., air
or water, a gel, an expanded plastic, or fibers. Such structure may
be formed of molded plastic, welded polymer, or a laminate. One
example of a suitable hydrophilic, flexible material for use in
wicking portion 23 is an open-cell foam such as hydrophilic
polyurethane. Alternatively, wicking portion may include any
suitable absorbent structure, e.g., a woven fabric, a nonwoven
fabric, a hydrogel (which may include modified starch), or a pouch
filled with a polymeric absorbent material. Any suitable adhesive
or bonding procedure can be used to adhere hydrophobic portion 22,
wicking portion 23, and hydrophobic barrier 24 together.
[0060] In the embodiment illustrated in FIG. 3A, support cushion 20
is pre-formed in a generally rectangular shape, and is suitable for
use with wounds up to a fixed size, e.g., up to 30 mm in length, or
up to 6'' in length. Support cushion 20 also may have a plurality
of perforations P defined therein, dividing support cushion 20 into
at least two interlocking portions, e.g., into two "J"-shaped
portions. Optionally, a plurality of additional perforations P may
be defined in support cushion 20 that are configured to enable
removal of specified portions of the support cushion, e.g.,
portions 31 and 32, by tearing the support cushion along one or
more of the perforations, and are also configured to allow the
remaining portions of the support cushion 20 to interlock with one
another, thus allowing the size of opening 29 to be reduced to more
closely circumscribe the wound. In one embodiment, the perforations
P are provided at 1/2'' intervals, allowing support cushion 20 to
be shortened in 1/2'' increments.
[0061] Alternatively, as illustrated in FIG. 3D, support cushion
20''' optionally may be preformed to include perforations enabling
the support cushion to be separated into separate portions, and
additional sections 33, 34 of support cushion material may be
provided to increase the size of opening 29. The additional
sections 33, 34 of support cushion material may be provided to the
caregiver in strips that include a plurality of such sections,
which are separable from one another by tearing along perforations.
In one example, the sections are provided in 1/2'' lengths,
allowing any desired multiple of 1/2'' lengths to be added to
lengthen support cushion 20''. Support cushion 20 alternatively may
be formed in any other appropriate shape and size and may be
provided having a range of size of openings 29. For example,
support cushion 20 may be pre-formed in a generally circular,
rectangular, triangular, or other polyhedral shape, optionally
having curved corners, or may even be pre-formed in an irregular
shape.
[0062] In the embodiment of FIGS. 1A-1B and 3A, wicking portion 23
is depicted as being thinner (shorter) than hydrophobic portion 22,
so as to define a recess into which reservoir 40 snugly fits. For
example, in some embodiments, the height of wicking portion 23 is
in a range of 40-60% of the height of the hydrophobic portion 22.
However, wicking portion 23 actually may have the same thickness
(height) as hydrophobic portion 22, and reservoir 40 may compress
the wicking portion 23 to a shorter height than hydrophobic portion
22 during use. For example, in the alternative support cushion 20'
illustrated in FIG. 3B, wicking portion 23' is as thick (as tall)
as hydrophobic portion 22, but has a different compliance, e.g., is
more easily compressed. Thus, during use, reservoir 40 may engage
the upper surface 28' of wicking portion 23', and compress the
wicking portion to a thickness (height) such that cover 50 contacts
adhesive 27 on the top surface 26 of hydrophobic portion 22, and
reservoir 40 fits snugly within hydrophobic portion 22. In other
embodiments (not illustrated), wicking portion 23' may even be
thicker (taller) than hydrophobic portion 22.
[0063] Additionally, not all embodiments require hydrophobic
barrier 24. For example, in the alternative support cushion 20''
illustrated in FIG. 3C, hydrophobic portion 22'' and wicking
portion 23'' both are adhered to the epidermis E via adhesive layer
25''. In the embodiment illustrated in FIG. 3C, wicking portion
23'' is thinner (shorter) than hydrophobic portion 22''. However,
as discussed above with respect to FIG. 3B, wicking portion 23''
alternatively may be as thick as, or even thicker than, hydrophobic
portion 22''.
[0064] Reservoir 40
[0065] As illustrated in FIGS. 1A-1B, reservoir 40 may include
multiple layers bonded together or alternatively may be formed of a
single, hydrophilic layer. In the embodiment of FIG. 1, reservoir
40 includes upper layer 43, lower layer 41 and intervening layer
42. Lower layer 41 engages the upper surface 28 of wicking portion
23, and transfers fluid through intervening layer 42, and into
upper layer 43. Although reservoir 40 is composed of breathable
materials that allow for the transfer of moisture vapor as needed,
reservoir 40 optionally may contain one or more vents 45 that
extend through the reservoir to improve moisture vapor transfer
through cover 50. For example, there may be one, two, three, or
more than three vents 45 extending through reservoir 40.
[0066] Referring again to FIG. 1B, both upper layer 43 and lower
layer 41 are hydrophilic. However, layers 41 and 43 may have the
same or different hydrophilicities, mechanical properties, transfer
rates for fluid, and capacities for absorbing fluid. In some
embodiments, layers 41 and 43 are formed from hydrophilic
polyurethane foams, e.g., commercially purchased polyurethane foams
from Rynel, Inc. (Wicasset, Me., USA). The foam from which lower
layer 41 is fabricated has a higher hydrophilicity than that of
upper layer 43, allowing it to rapidly transfer exudate into upper
layer 43. The polyurethane foams may be coated or interlaced with
any suitable antibacterial, wound healing, or antimicrobial agents
(e.g., silver) to combat or prevent infection.
[0067] Intervening layer 42 enhances the strength and stiffness of
reservoir 40, making it more difficult to inadvertently deflect
reservoir 40 downward to contact the wound and inhibiting potential
collapse of the reservoir into contact with the wound. Intervening
layer 42 may be, for example, a substantially non-stretchable mesh
or scrim, such as a metallic, nylon, or polyester-based mesh.
[0068] As discussed herein, in some embodiments support cushion 20
has optional perforations defined therein that allow specified
sections of the support cushion to be removed. In such embodiments,
it may be advantageous to also provide perforations P' in reservoir
40, thus allowing portions of the reservoir 40 to be removed by
tearing the reservoir along the perforations, e.g., to remove
portions 46 and 47. In this manner, reservoir 40 may be resized as
needed to fit snugly over the wicking portion 23 of support cushion
20. In one example, the perforations P' are provided at intervals
that are one-half the length of the intervals for perforations P,
e.g., P' are perforated at 1/4'' intervals when P are perforated at
1/2'' intervals.
[0069] Cover 50
[0070] Referring now to FIGS. 1B and 4, cover 50 is described
having pre-fastened reservoir 40 with vent 45. Cover 50 may be
adhered to upper layer 43 with a layer of adhesive, or otherwise
attached to upper layer 43 before or after reservoir 40 is placed
over the wound. Preferably, cover 50 is not attached to those
sections of reservoir 40 that are configured for optional removal
using perforations P'.
[0071] During use, cover 50 is adhered to the upper surface of
hydrophobic portion 22 using layer 27 of adhesive, for example a
biocompatible adhesive, which urges reservoir 40 against wicking
portion 23. In other embodiments, layer 27 may comprise a removable
fastener, such as a hook and pile arrangement or a repositionable
adhesive that enables the cover 50 and reservoir 40 to be
periodically removed to inspect the wound, apply medicaments,
and/or to replace the reservoir 40 without entirely removing the
dressing, e.g., without removing the support cushion 20.
[0072] In some embodiments, cover 50 extends beyond the lateral
dimensions of support cushion 20, so that when dressing 10 is
applied to a patient, cover 50 drapes over support cushion 20 and
covers layer 27 of adhesive. Such draping protects the edges of
support cushion 20 from lifting, and additionally provides a
smooth, comfortable surface over which clothing and bed linens may
slide freely.
[0073] Cover 50 is made of a soft, occlusive material that provides
an antibacterial barrier between the wound W and the environment,
and also allows humidity to escape from reservoir 40 and vent 45.
One example of a suitable material for cover 50 is Intelicoat 5243,
available from Intelicoat Technologies (South Hadley, Mass., USA).
Other suitable materials include foams, wovens, and nonwovens. The
material may be coated or intercalated with any suitable
antibacterial or antimicrobial agent to combat or prevent
infection.
[0074] Kits
[0075] The components of a dressing constructed in accordance with
the principles of the present invention, illustratively dressing 10
of FIGS. 1A-1B, may be provided to patients or caregivers as a kit
70, illustrated in FIG. 5A. Kit 70 includes a cardboard or other
sturdy, disposable backing 71 upon which support cushion 20,
reservoir 40, and cover 50 are removably mounted. Examples of
alternative disposable backings 71 include dark, colored or
translucent trays of materials such as polystyrenes (for example
available from Sealed Air Corp., Elmwood Park, N.J., USA; or
Perfecseal.RTM., a BEMIS Co., Oshkosh, Wis., USA; or Universal
Plastics Corp., Holyoke, Mass., USA). Kit 70 may also include
additional components, e.g., different sizes and shapes of support
cushion 20, reservoir 40, and/or cover 50, or portions of support
cushion 20 and/or reservoir 40 that may be inserted in those
components to increase their size, to be able to accommodate
different sizes and shapes of wounds (not illustrated). In an
alternative embodiment, the components of dressing 10 are instead
provided in one or more compartments of a tray.
[0076] In the illustrated embodiment, pieces of excess material
adhered to backing 71 may be used to secure the components of
dressing 10 to backing 71 until they are needed. For example,
opening 29 in support cushion 20 may be formed by cutting piece 73
from one or layers of the material from which the support cushion
is formed (e.g., the material from which wicking portion 23 is
formed, and/or the material from which hydrophobic barrier 24 is
formed, and/or the material from which hydrophobic portion 22 is
formed), and then adhering that piece 73 to backing 71. Because
piece 73 snugly fits into the hole of support cushion 20, friction
between piece 73 and support cushion 20 serves to removably retain
support cushion 20 on backing 71 without the need for additional
adhesive or tabs, until removed by the patient or caregiver.
Similarly, reservoir 40 may be cut from the center of a larger
piece 74 that is subsequently adhered to backing 71. Friction
between reservoir 40 and piece 74 retains reservoir 40 frictionally
engaged on backing 71 without the need for additional adhesive or
tabs, until removed for use. Any other material may be used to
frictionally engage reservoir 40 and/or support cushion 20 on
backing 71. Alternatively, as illustrated in FIG. 5B, in kit 70'
foldable tabs 72 cut from backing 71 may be used to secure some or
all of the components onto backing 71.
[0077] Referring again to FIG. 5A, instructions for use 75 for
applying the different components of dressing 10 to a patient may
be printed on backing 71, e.g., instructions for implementing the
method described with respect to FIG. 2. Alternatively,
instructions may be printed on the packaging medium. The
instructions may be sterilized so that they may be safely used in a
sterilized field, such as an operating room. The adhesive layers on
the different components are covered with non-stick, removable
liners that may be color coded or have a series of perforations or
symbols to guide the patient or caregiver in determining the order
in which to apply the components of dressing 10. Such non-stick
liners may facilitate handling of the different components of
dressing 10, e.g., while placing support cushion 20 on the
patient's epidermis.
[0078] Kit 70 preferably further includes a pouch (not shown) in
which backing 71 and dressing 10 are sealed until needed.
Preferably, the pouch is transparent on at least its upper surface,
allowing backing 71 and the other components to be viewed.
Additionally, instructions for use 75 may be located on backing 71
so as to make possible reading of the instructions before opening
the pouch. The pouch also may be constructed to aid retention of
the components of dressing 10 on backing 71. Kit 70 preferably is
sterilizable, e.g., may be sterilized after assembly, such that the
contents of the pouch remain sterile until it is opened, e.g.,
immediately before the dressing is applied to a patient. The pouch
preferably comprises a material that retains its integrity during
conventional sterilizing procedures, e.g., exposure to gamma
radiation, an electron beam, hydrogen peroxide, or ethylene oxide
gas.
[0079] It is envisioned that a typical wound care treatment
environment, such as a hospital, wound care outpatient clinic or
doctor's office, may stock an inventory of kits 70 designed for use
with different sizes or shapes of wounds. For example, a plurality
of kits 70 may be manufactured having support cushion 20, reservoir
40, and cover 50 in a variety of sizes and shapes, according to
different wound sizes and shapes with which they may be suitable
for use. Alternatively, or in addition, individual components of
the dressing, such as the reservoirs, may be individually packaged,
for example to permit periodic replacement of the reservoir with
greater frequency than the dressing as a whole.
[0080] Alternative Configurations
[0081] As noted above, support cushions and reservoirs suitable for
use in the inventive dressing may be configured to accommodate
different shapes and sizes of wounds. For example, FIGS. 6A and 6B
illustrate an alternative dressing in which a support cushion 80
and reservoir 85 include perforations enabling removal of selected
portions of these components both along the minor axis and along
the major axis. Specifically, like support cushion 20 described
above, alternative support cushion 80 includes perforations P that
enable removal of selected portions of the support cushion along
the major axis to reduce a length of the support cushion along the
major axis, e.g., removal of portions 31 and 32. Support cushion 80
additionally includes perforations PA that enable removal of
selected portions of the support cushion along the minor axis to
reduce a width of the support cushion along the minor axis, e.g.,
removal of portions 81 and 82. Similarly, like reservoir 40
described above, alternative reservoir 85 includes perforations P'
that enable removal of selected portions of the reservoir along the
major axis to reduce a length of the reservoir along the major
axis, e.g., removal of portions 46' and 47'. Reservoir 85 also
includes perforations PA' that enable removal of selected portions
of the reservoir along the minor axis to reduce a width of the
reservoir along the minor axis, e.g., removal of portions 48 and
49.
[0082] It should be noted that in still other embodiments, support
cushion 80 and/or reservoir 85 may only include perforations
enabling removal of selected portions of these components along the
minor axis, e.g., include perforations PA and PA', but not
perforations P and P'.
[0083] Additionally, as noted above, dressings may be formed in
shapes other than rectangular. For example, as illustrated in FIG.
7, in one alternative embodiment support cushion 90, reservoir 95,
and cover 96 are elliptically shaped. Support cushion 90 includes
sidewalls 99 defining a major axis and a minor axis, and optionally
including at least two perforations PB that traverse the sidewalls
at offset locations, thus dividing support cushion 90 into two
asymmetrical "C"-shaped portions that interlock with one another.
Optionally, support cushion 90 includes additional perforations PB
that enable removal of selected portions of the support cushion
along the major axis to reduce a length of the support cushion
along the major axis, e.g., removal of portions 91 and 92.
Reservoir 95 includes optional vent holes 45, which may be the same
as the vent holes 45 described above, and optionally also includes
perforations PB' that enable removal of selected portions of the
reservoir along the major axis to reduce a length of the reservoir
along the major axis, e.g., removal of portions 93 and 94. Note
that because of the curvature of support cushion 90 and reservoir
95, both the length and the width of these components may be
reduced when portions are removed.
[0084] While various illustrative embodiments of the invention are
described above, it will be apparent to one skilled in the art that
various changes and modifications may be made therein without
departing from the invention. The appended claims are intended to
cover all such changes and modifications that fall within the true
spirit and scope of the invention.
* * * * *