U.S. patent application number 16/402051 was filed with the patent office on 2019-08-22 for closed incision negative pressure wound therapy device and methods of use.
The applicant listed for this patent is KCI Licensing, Inc.. Invention is credited to Kenton FONG, Dean HU, Akshay MAVANI, Moshe PINTO, Kenneth WU.
Application Number | 20190254879 16/402051 |
Document ID | / |
Family ID | 40549608 |
Filed Date | 2019-08-22 |
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United States Patent
Application |
20190254879 |
Kind Code |
A1 |
HU; Dean ; et al. |
August 22, 2019 |
Closed Incision Negative Pressure Wound Therapy Device And Methods
Of Use
Abstract
A surgical tissue therapy device includes a sealant layer and a
collection chamber. The sealant layer functions so as to create a
sealed enclosure or space between it and the surface of a patient
by forming, preferably, an airtight seal around a surgical area of
skin trauma. The closed incision tissue therapy device also
comprises a collection chamber, which may comprise an elongate
tubular chamber with a plurality of longitudinally spaced openings.
The collection chamber may be configured to be in fluid
communication with the sealant layer and the area of skin trauma
and functions as to distribute the negative pressure applied to a
surgically closed area of skin trauma. Preferably, the pressure
under the sealant layer is reduced by expanding the volume of the
enclosure space and thereby decreasing the density of air molecules
under the sealant layer. The collection material may comprise a
material and/or a configuration that permits length changes based
upon the length of the corresponding surgical wound or
incision.
Inventors: |
HU; Dean; (San Leandro,
CA) ; PINTO; Moshe; (Mountain View, CA) ;
FONG; Kenton; (Mountain View, CA) ; MAVANI;
Akshay; (Los Altos, CA) ; WU; Kenneth; (San
Francisco, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KCI Licensing, Inc. |
San Antonio |
TX |
US |
|
|
Family ID: |
40549608 |
Appl. No.: |
16/402051 |
Filed: |
May 2, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15216500 |
Jul 21, 2016 |
10322033 |
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16402051 |
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14484578 |
Sep 12, 2014 |
9421133 |
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15216500 |
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14058175 |
Oct 18, 2013 |
8834434 |
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14484578 |
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13004819 |
Jan 11, 2011 |
8562576 |
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14058175 |
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12249759 |
Oct 10, 2008 |
8246590 |
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13004819 |
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60979315 |
Oct 11, 2007 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 13/00068 20130101;
A61F 13/02 20130101; A61F 13/0226 20130101; A61F 13/0216 20130101;
A61F 13/0266 20130101; A61F 2013/00536 20130101; A61M 1/0088
20130101; A61F 2013/00174 20130101; A61M 27/00 20130101; A61F
13/00063 20130101 |
International
Class: |
A61F 13/00 20060101
A61F013/00; A61F 13/02 20060101 A61F013/02; A61M 35/00 20060101
A61M035/00; A61M 1/00 20060101 A61M001/00; A61M 27/00 20060101
A61M027/00 |
Claims
1. A device for treating a wound, the device comprising: a support
configured to be positioned over a length of an incision in tissue,
the support comprising: at least one central channel configured to
be in communication with the incision, and at least one side
channel; and a sealant structure configured to form a sealed space
at the incision, wherein one or both of the sealant structure and
the support are configured to pull a first edge of the incision
toward a second edge of the incision when the sealed space receives
reduced pressure.
2. The device of claim 1, wherein the support is configured to be
positioned over an entire length of the incision in the tissue.
3. The device of claim 1, further comprising a contact layer
configured to positioned within the sealed space and to be in
direct contact with at least a portion of the incision in the
tissue.
4. The device of claim 1, further comprising a suction source
configured to generate the reduced pressure.
5. The device of claim 4, wherein the suction source comprises a
constant force spring.
6. The device of claim 4, wherein the suction source comprises a
sliding seal.
7. The device of claim 4, wherein the suction source is directly
coupled to a surface of the sealant structure that is configured to
be exposed to an ambient environment.
8. The device of claim 1, wherein the sealant structure comprises a
surface with an adhesive disposed around at least a portion of a
perimeter of the surface, and wherein the adhesive is configured to
secure at least the portion of the perimeter of the surface to an
area of tissue around the incision.
9. The device of claim 1, wherein the sealant structure is
configured to collapse around the support when the sealed space
receives the reduced pressure.
10. The device of claim 1, wherein the central channel is an
elongated channel.
11. The device of claim 10, wherein a contact layer is configured
to provide fluid communication between the elongated channel and
the incision in the tissue.
12. The device of claim 1, wherein the central channel is
configured to be positioned along the incision and to distribute
the reduced pressure to the incision in the tissue.
13. The device of claim 1, wherein the sealant structure comprises
at least one elastic element configured to pull the first edge of
the incision to the second edge of the incision.
14. The device of claim 1, wherein the sealant structure is
positioned over the support.
15. The device of claim 1, wherein the central channel is open and
exposed to the incision.
16. The device of claim 1, wherein the central channel includes a
plurality of longitudinally arranged openings along at least a
portion of the central channel.
17. The device of claim 1, wherein the sealant structure is
configured to form the sealed space over the support and the
incision.
18. The device of claim 1, wherein the support further comprises: a
flange positioned on at least one side of the central channel, and
a cap structure positioned on an upper surface of the central
channel and configured to project to at least one side of the
central channel, wherein the side channel is positioned between the
cap structure and the flange.
19. The device of claim 1, wherein the sealant structure is
configured to collapse into the side channel when the sealed space
receives the reduced pressure.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/216,500, filed Jul. 21, 2016, which is a
continuation of U.S. patent application Ser. No. 14/484,578,
entitled "CLOSED INCISION NEGATIVE PRESSURE WOUND THERAPY DEVICE
AND METHODS OF USE," filed Sep. 12, 2014, now U.S. Pat. No.
9,421,133 which is a continuation and claims priority under 35
U.S.C. .sctn. 120 of co-pending U.S. patent application Ser. No.
14/058,175, filed on Oct. 18, 2013, now U.S. Pat. No. 8,834,434,
entitled "CLOSED INCISION NEGATIVE PRESSURE WOUND THERAPY DEVICE
AND METHODS OF USE," which is a continuation of U.S. patent
application Ser. No. 13/004,819, filed on Jan. 11, 2011, now U.S.
Pat. No. 8,562,576, which is a continuation of U.S. patent
application Ser. No. 12/249,759, filed on Oct. 10, 2008, now U.S.
Pat. No. 8,246,590, which claims priority under 35 U.S.C. .sctn.
119(e) to U.S. Provisional Application Ser. No. 60/979,315 filed on
Oct. 11, 2007. Priority of the aforementioned filing dates is
hereby claimed and the disclosures of the patent applications are
hereby incorporated by reference in their entirety.
BACKGROUND
[0002] There are millions of closed incisions (surgical or non
surgical) each year, that occur in settings ranging from
office-based procedures and ambulatory surgical centers to
traditional in-patient hospital settings. Post-procedural care of
these incisions may vary, but can involve simple use of gauze,
wraps and tapes. In addition, irrigation of the wound prior to
closure and meticulous sterile technique has also been advocated.
Wound infections following invasive procedures and surgeries
presents a potential risk to patients that can be as high as 10%
with abdominal surgeries, for example. Wound infections are a
significant morbidity for patients, clinicians, and hospitals and
can be costly to taxpayers and other payors. Patients with wound
infections may need IV antibiotics, prolonged hospitalization,
wound opening and dressing changes, and some go on to develop wound
dehiscence and enterocutaneous fistulas. While pre-operative
prophylactic antibiotics have been shown to decrease post-operative
wound infection, post-operative antibiotics have not.
SUMMARY
[0003] Provided herein is a device for treating a surgically closed
incision. In one embodiment of the device provided herein, the
device comprises a sealant layer and a collection chamber. In some
embodiments, the sealant layer may be adapted and configured to
create a seal around a surgically closed area of skin trauma,
thereby forming a sealed enclosure or space. In addition, the
collection chamber may be adapted and configured to distribute
pressure changes throughout at least a portion of the sealed
enclosure or space created by the sealant layer.
[0004] Further provided herein is a device for the treatment of a
closed incision wherein the device further comprises a suction
source. The suction source may be in fluid communication with the
sealed enclosure. In some embodiments of the device, the suction
source may be adapted and configured to reduce the level of
pressure located inside of the sealed enclosure. In some
embodiments, the device may comprise a contact layer. The contact
layer may be adapted and configured to be in communication with the
collection chamber of the device. In some embodiments, the contact
layer has a conduit or opening that permits fluid communication
with the collection chamber.
[0005] In a further embodiment of the device, the device may
comprise a protective layer. The protective layer may be used to
affix the contact layer to the surgically closed area of skin
trauma. In an embodiment where a protective layer is used, the
protective layer may be further adapted and configured to protect
the skin adjacent to the surgically closed area of skin trauma.
[0006] Also provided herein is a closed incision therapy device,
comprising a collection chamber. In some embodiments, the
collection chamber may be in a pre-evacuated state before the
collection chamber is used with the device. In some embodiments,
the collection chamber is deformable or bendable by the user or
healthcare provider. In a further embodiment, the collection
chamber comprises a flexible tube. The flexible tube may be
configured to deform or bend in response to changes in the surface
topology of the surgically closed area of skin trauma.
[0007] In a further embodiment of the device described herein, the
collection chamber comprises a flexible tube with discrete
collection members for collecting exudate or other suitable
material. In some embodiments, the flexible tube comprises a single
discrete collection member, but in other embodiments, the flexible
tube comprises two or more discrete collection members. At least
one of the discrete collection chambers may be in communication
with the flexible tubing. For example, the discrete collection
members may be in fluid communication with the flexible tubing. In
an embodiment where at least two discrete collection members are
used, the discrete collection members may be in communication with
other discrete collection members and may be separated by a segment
of flexible tubing. In some embodiments, two or more of the
discrete collection members may be in fluid communication with each
other. In some embodiments, the flexible tubing and the discrete
collection members are adapted and configured to be integrated with
the sealant layer, while in other embodiments, the discrete
collection members but not the flexible tubing are adapted and
configured to be integrated with the sealant layer. In a further
embodiment of the collection chamber provided herein, the
collection chamber may comprise a series of openings. In such an
embodiment, the series of openings are adapted and configured to
provide fluid communication between the collection chamber and the
surgically closed area of skin trauma.
[0008] In some embodiments, the collection chamber comprises a
support integrated into the walls of the collection chamber. The
support structure may be adapted and configured to allow the user
to shape the collection chamber into a particular configuration.
The support structure may further maintain or resist changes to the
shape of the particular configuration, or at least until a new
configuration is desired by the user.
[0009] In some embodiments, the collection chamber preferably
comprises a one-way flow valve. In some embodiments, the one way
flow valve is adapted and configured to facilitate the emptying of
the collection chamber. The one-way flow valve may be further
adapted and configured to facilitate the re-creation of a reduced
level of pressure inside the collection chamber and/or to restore
the collection chamber to its original pre-evacuated state.
[0010] In some embodiments, the collection chamber may be a dual
chamber collection chamber. For example, the dual chamber
collection chamber may comprise a first chamber and a second
chamber, where the first and second chamber are in communication
with each other. In some embodiments, the second chamber may
further comprise an actuating and/or regulating mechanism. The
actuating and/or regulating mechanism may be a non-powered or
passive actuating mechanism. In such an embodiment, the second
chamber is adapted and configured to expand a volume of air located
in a joint volume of space shared between the sealed enclosure and
the dual chamber collection chamber. In some embodiments, the dual
chamber collection chamber comprises a reciprocating mechanism.
[0011] As mentioned above, the device may further comprise a
contact layer. The contact layer may serve as a vehicle for the
delivery of one or more agents that augment the healing process. In
some embodiments, the agents may include a pharmacological or
biological agent. In some embodiments, the contact layer is a
porous dressing interface.
[0012] In some embodiments, a wound treatment device may be adapted
and configured to conform to the length of the surgically closed
area of skin trauma. In other embodiments, the wound treatment
device may be cut to size. In some examples, the collection chamber
of the wound treatment device is adapted and configured to conform
to the length of the surgically closed area of skin trauma. In
other examples, the contact layer and/or the sealant layer may be
configured to conform to the length of the surgically closed area
of skin trauma. In some embodiments, the sealant layer may be
configured to be semi-rigid. In such an embodiment, the sealant
layer may be configured to provide tensile support to the
surgically closed area of skin trauma. In such an embodiment, the
sealant layer may be adapted to alleviate mechanical tension.
[0013] In some embodiments, the device may further comprise
absorbent beads or other absorbent structures. In some embodiments
the device may further comprise antimicrobial agents. In some
embodiments, the device is configured to be emptied and further
configured to be re-evacuated. In some embodiments, the device is
configured to deliver reduced pressure between about 0.001 to about
1 atmosphere. In some embodiments the level of atmospheric pressure
underneath the sealant layer may be reduced to about 0.001 atm or
higher, but in other embodiments to about 0.005 atm, about 0.01
atm, about 0.05 atm, about 0.1 atm, about 0.2 atm, about 0.5 atm,
about 0.7 atm, or about 0.9 atm. In some embodiments, the
atmospheric pressure underneath the sealant layer is reduced to
less than about 0.8 atm, about 0.7 atm, about 0.6 atm, about 0.4
atm, about 0.3 atm, about 0.2 atm, about 0.1 atm, about 0.07 atm,
about 0.03 atm, about 0.007 atm, or even to less than about 0.003
atm.
[0014] In some embodiments of the device provided herein, the
contact layer, the sealant layer, and/or the collection chamber are
further configured to be translucent or transparent so as to
facilitate application to the incision site.
[0015] In another embodiment, a wound treatment device is provided,
wherein the wound treatment device comprises a flexible sealant
structure with an upper surface, a lower surface and an adhesive, a
collection structure integrally formed with the flexible sealant
structure and comprising a wall and an internal space surrounded by
the wall, and a plurality of passageways between the internal space
of the collection structure and the lower surface of the flexible
sealant structure and passing through the wall of the collection
structure and through the upper surface of the flexible sealant
structure. In some examples, there are at least three passageways.
Also, in some examples the device further comprises a suction
source and/or a suction port in fluid communication with the
internal space of the collection structure. The suction source may
comprise a constant force spring and/or a sliding seal. In some
instances, the suction source has a fixed external profile
independent of its internal pressure level. In some specific
examples, the suction source may be integrally formed with the
collection structure. In regards to the collection structures, the
collection structure may be a collection tube comprising a first
end and a second end, and the plurality of passageways may be
longitudinally spaced between the first and the second end of the
collection tube. In some instances, the collection structure may be
a flexible collection structure.
[0016] In another embodiment, a method for treating a closed
incision is provided, where the method or procedure comprises
forming a sealed space along a closed incision using a sealant
layer, wherein the closed incision was formed by wound edges
previously attached to each other and reducing pressure in the
sealed space. The method may also further comprise mechanically
pushing the wound edges against each other using the sealant layer,
contracting the sealant layer onto a support structure, and/or
reducing tissue tension variations along the sealed space. The
closed incision may be any of a variety of closed incisions,
including but not limited to those closed with sutures or staples.
The sutured incisions may be interrupted sutures, running or
continuous sutures, and the like.
[0017] Further provided herein is a method of applying reduced
pressure therapy to a surgically closed area of skin trauma,
comprising (a) sizing a collection chamber, a protective layer and
a sealant layer to a size of the surgically closed area of skin
trauma, (b) forming a seal around said the surgically closed area
of skin trauma, (c) activating said collection chamber to deliver
reduced pressure to the surgically closed area of skin trauma, and
(d) removing the device after at least some re-epithelialization of
the surgically closed area of skin trauma. The method further
provides a collection chamber wherein the reduced pressure is
distributed through the surgically closed area of skin trauma.
[0018] A method for treating a surgically closed area of skin
trauma using a reduced pressure therapy device comprising the steps
of (a) cutting a flexible protective layer to the shape of an area
of skin trauma, (b) attaching the cut protective layer to an area
of intact skin surrounding the area of skin trauma, (c) cutting a
flexible adhesive dressing with an integrated layer of foam to a
desired size, said flexible adhesive dressing integrated with said
layer of foam in fluid communication with a flexible tubing, (d)
placing the dressing over said surgically closed area of skin
trauma to form a sealed enclosure, (e) configuring the tubing with
an end piece, (f) charging the device, (g) recharging the device as
necessary to remove exudates and to restore reduced pressure inside
said enclosure, and (h) removing the device after at least some
wound re-epithelialization. The method for treating a surgically
closed area of skin trauma includes trauma selected from a cut,
puncture wound, surgical incision, and any combination thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The features of the invention are set forth with
particularity in the appended claims. A better understanding of the
features and advantages of the present invention will be obtained
by reference to the following detailed description that sets forth
illustrative embodiments, in which the principles of the invention
are utilized, and the accompanying drawings of which:
[0020] FIGS. 1A and 1B depict one embodiment of a negative pressure
therapy device as viewed from the top and from the side
perspective.
[0021] FIG. 2 depicts an embodiment of a negative pressure therapy
device as viewed from above in which the device is designed to be
emptied and re-evacuated.
[0022] FIG. 3 depicts an embodiment of the negative pressure
therapy device as viewed from above in which the collection chamber
is a segmented collection chamber.
[0023] FIG. 4 depicts an embodiment of the negative pressure
therapy device in which an occlusive layer is placed over the
collection chamber.
[0024] FIG. 5 depicts an embodiment of the negative pressure
therapy device in which the collection chamber comprises corrugated
tubing segments interspersed with discrete collection members.
[0025] FIG. 6A is a perspective view of another embodiment of a
negative pressure therapy device; FIG. 6B and 6C are axial
cross-sectional views of the device in FIG. 6A, before and after
the application of reduced pressure, respectively.
[0026] FIG. 7 is a schematic perspective view of two wound
coverings joined together.
[0027] FIG. 8 depicts another embodiment of the negative pressure
therapy device, comprising a split support.
[0028] FIG. 9A is a perspective view of another embodiment of a
negative pressure therapy device comprising an elastic collection
channel; FIGS. 9B to 9D are schematic cross-sectional views of the
device in FIG. 9A before, during and after stretching,
respectively; FIG. 9E is a schematic perspective view of two
negative pressure therapy devices joined together.
[0029] FIGS. 10A to 10C are schematic cross-sectional views of
another negative pressure therapy device with reinforced apertures,
before, during and after stretching, respectively.
[0030] FIGS. 11A to 11C are schematic cross-sectional views of
another negative pressure therapy device comprising an open
longitudinal channel, before, during and after stretching,
respectively.
[0031] FIG. 12 is a schematic illustration of an elongate negative
pressure therapy system arranged around a perimeter of a wound.
[0032] FIG. 13 is schematic illustration of an elongate negative
pressure therapy system arranged in a spiral orientation about a
wound.
[0033] FIG. 14 is schematic illustration of an elongate negative
pressure therapy system arranged in a zig-zag orientation about a
wound.
[0034] FIGS. 15 is schematic illustration of an elongate negative
pressure therapy system arranged in a T-orientation about a
wound.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Infections of surgical incisions and other wounds may result
from bacterial growth that occurs in small pockets of fluid
collections that may form within the subcutaneous tissues. These
small fluid collections lack blood flow and thus may provide
inadequate immune function or antibiotic penetration to prevent or
treat infection. Once contaminated with bacteria, there can be
unfettered growth in these areas. Thus, by reducing the formation
of these fluid collections, the risk of a wound infection may be
reduced. Although some closure techniques utilize dermal or deep
sutures to reduce the formation of these fluid pockets, these
sutures may also act as foreign bodies that may increase the risk
of wound infection. Furthermore, improper suturing technique may
still leave significant dead space under the skin that allows for
fluid to collect and eventually become contaminated by bacteria. In
addition to wound infection, wound healing may inhibited by
excessive tension on the wound. Excessive tension may result from
sutures or other wound closure devices that exert focal forces on
portions of the incision or wound, and may also lead to increased
scarring.
[0036] Studies have also demonstrated that a moist wound healing
environment may promote more rapid re-epithelialization of wounds
by facilitating cell migration toward the wound center, in contrast
to current gauze dressings that create a dry wound environment.
Moreover, surgical and other wounds undergo of immune cell
infiltration, inflammation and subsequent edema. The immune
response may be an integral process of wound healing, but the
ensuing edema may also be an impediment to healing. Finally, proper
healing requires oxygen and nutrients which require adequate
perfusion to the incision site which may be impeded by some of the
immunological processes.
[0037] In one example, a negative or reduced pressure wound therapy
system may be used to treat of areas of skin trauma that have been
surgically closed, or other types of elongate lacerations or
wounds. The negative pressure wound therapy system may comprise a
sealant layer and a collection chamber. The sealant layer may be
designed such that it can form a seal around a surgically closed
area of skin trauma, such as the surgical incision, and form a
sealed enclosure or space. In some examples, the sealant layer may
comprise a single piece or body, while in other examples, the
sealant layer may comprise multiple pieces that may be applied
together to form an enclosed space or area. The sealant layer may
also comprise a single layer of material, or multiple layers of
materials. The seal may be sufficiently air tight so that the
pressure in the sealed enclosure or space may be reduced and
maintained at a reduced level. The negative pressure therapy system
may also comprise a collection chamber that is configured to
distribute the reduced pressure applied to the surgically closed
incision site along the length of the incision or wound. The
negative pressure therapy system may also be used to treat a
surgical incision left open to heal by secondary intention, or by
delayed primary closure (i.e. third intention). The system may
comprise a collection chamber in continuity to a surgical incision
that is sealed in a closed system as created by a sealant layer.
The collection chamber, when activated, may generate a negative
pressure at the surgical incision site to promote healing, remove
exudate, and/or reduce infection rates, for example. In some
particular examples, the system provided herein may have an
elongate configuration and may be sized or configured to conform to
the length of the surgical incision. The collection chamber may be
integrally formed or pre-attached to a sealant layer, or the
collection chamber and the sealant layer may be configured to
permit the collection chamber to be positioned under the sealant
layer.
[0038] In some embodiments, the system further comprises a suction
apparatus. When the suction apparatus is used with the system, the
suction apparatus may be configured to be in communication with the
sealed enclosure or space. The suction apparatus, together with the
sealant layer and collection chamber, may form a closed system for
treating a surgical incision or other type of wound. The suction
apparatus, when engaged, may be used to reduce the level of
pressure located inside the sealed enclosure by forcefully
expanding the volume of air located within the sealed enclosure.
The suction source may be a closed or open system. For example, the
suction apparatus may be a syringe, a powered pump, a Venturi
system, a forced expansion device, constant force spring device, or
a static negative pressure device, or any suitable active or
passive suction source. In some embodiments, the suction source may
be integrally formed with the collection chamber. In some
embodiments, the suction source is connected to the collection
chamber through the use of an extension tube.
[0039] In some embodiments, the system further comprises a contact
layer. The contact layer may be configured to permit fluid
communication with the collection chamber. The contact layer may be
placed in contact with the surface of the surgically closed area of
skin trauma. In some embodiments, the contact layer may only be in
contact with the surgically closed area of skin trauma and may not
be in contact with the area surrounding the site of trauma. In
other embodiments, the contact layer may be in contact with both
the area of skin trauma and the area surrounding the area of skin
trauma. The contact layer may facilitate the continuity of fluid
communication between the collection chamber and the surgical area
of skin trauma. In some examples, the contact layer may comprise a
porous material or other structure comprising air spaces,
including, but not limited to, foam, a stacked mesh matrix, gauze,
cotton, a sponge, or any known suitable material in the art. In
some embodiments where the contact layer is used, the contact layer
may serve as a delivery vehicle for delivery agents. The delivery
agents may include, but are not limited to, growth factors,
antibiotics, antimicrobial agents, or any suitable delivery agent.
In some embodiments, the agents used to improve healing are
integrated with the contact layer. In some embodiments, the agents
used are integrated or located with the collection chamber.
[0040] In some embodiments, the system further comprises a
protective layer. A protective layer may be used to surround the
surgical area of skin trauma. For example, the protective layer may
be attached or adhered to the area of skin surround the area of
skin trauma. A pressure sensitive adhesive on the underside of the
protective layer may provide the attachment or adherence properties
to the skin. A protective layer may also be used to form a seal in
combination with a sealant layer. The seal is airtight, or may be
semi-permeable or impermeable to water vapor. In some embodiments,
the protective layer may be sized to the surgical area of skin
trauma such that it fits around the area of skin trauma. In some
examples, the protective layer may be cut to size, but in other
embodiments, the protective layer may comprise perforations or
other pre-defined separation structures to facilitate the sizing.
In certain embodiments, the protective layer may have a thin
central peel-away strip or layer that may be removed after the
protective layer has been placed around the area of skin trauma. In
such embodiments, a wider contact layer may be placed over the
protective layer. The protective layer may be used to affix the
contact layer to the surgical area of skin trauma, and may protect
the underlying skin or tissue from trauma associated with removal
of the contact layer to access the surgical site. The protective
layer can be any known material suitable for protecting the skin
surrounding the skin trauma from maceration. The protective layer
may comprise any of a variety of foam and/or hydrocolloid
materials, including Duoderm.RTM. wound care products.
[0041] The collection chamber of the static negative pressure
therapy system may be configured to distribute the pressure levels
applied to the incision site over the length of the surgically
closed area of trauma. In some embodiments, the collection chamber
may be in a pre-evacuated state prior to being placed on the
surgically closed incision area of skin trauma. In such an
embodiment, the collection chamber, once in communication with the
area of skin trauma, can then be activated to apply reduced
pressure to the area of skin trauma. In some examples, the
collection chamber comprises a tubular structure. The tubular
structure may comprise a rigid tube, for example, a moldable or
flexible tube. The tube may comprise a deformable or elastic
support that permit the tube to be bent or shaped into a particular
configuration while also allowing the tube to holding or biasing
the tube in that configuration. For example, the support structure
may comprise a wire mesh cage or frame surrounding the tube,
coupled to the inner lumen of the tube, or otherwise supporting the
tube. In some embodiments, the tube has a wire support structure
integrally within the walls of the tube. The support structure may
also comprise a moldable plastic material, or the tubing itself may
comprise a moldable plastic including. Moldable materials include,
but are not limited to, thermoplastics, elastomeric materials, or
any suitable moldable material. In some embodiments, the collection
chamber may be configured for single use only, while in other
embodiments, the collection chamber may be emptied and re-evacuated
during use.
[0042] In some embodiments, the collection chamber is a flexible
tube which comprises one or more corrugated sections. In such an
embodiment, the corrugated tubing section may be flexible and can
conform to the surface topology of the surgically closed area of
skin trauma. The corrugated tubing sections may allow the flexible
tubing to conform to the two-dimensional or three-dimension
configuration of the wound or incision and allows the tubing to
passively adjust in response to changes in the wound configuration
as the patient moves or as the wound heals. In some embodiments,
the flexible tube may comprise entirely of corrugated tubing, while
in other embodiments, the flexible tubing is corrugated tubing
sections with discrete collection members or non-corrugated
sections located therebetween. In one embodiment, the
non-corrugated sections may be rigid, or may be semi-rigid or
flexible but with less flexibility than the corrugated sections.
Some embodiments may comprise at least one non-corrugated section
located within the tubing, while other embodiments may comprise two
or more non-corrugated sections located along the tubing. The
tubular segments may be connected by corrugated tubes that provide
fluid communication along a length of the tubing and/or provide
flexibility to the tubing such that the entire collection chamber
structure, the rigid non-corrugated sections and the flexible
corrugated tubing sections overall permit conformation to the skin
or surgical site as it moves. Sometimes, flexible tubing may
mitigate the discomfort to the patient or reduce the localized
pressure points from the treatment system. In some embodiments
comprising both rigid collection sections and flexible sections
along the collection chamber, both the flexible tubing segments and
the rigid collection sections may be embedded into the sealant
layer, coupled to the sealant layer, or integrally formed with the
sealant layer. In some embodiments, only the discrete collection
members are coupled or embedded into the sealant layer, while the
flexible tubing segments are not.
[0043] Some embodiments of the system comprise a collection chamber
and a sealant layer, where the sealant layer and the collection
chamber are in fluid communication with an area of skin trauma.
Fluid communication may be provided by a series of openings in the
sealant layer and the collection chamber which provide fluid
communication between the area of skin trauma and the collection
chamber. The openings may be located longitudinally oriented along
a length of the collection chamber, with corresponding openings of
the sealant layer aligned with the openings in the collection
chamber. Fluid, or any other suitable matter, may then be drawn up
from the surgically closed area of skin trauma into the collection
chamber. When an optional contact layer is employed, the fluid may
passes first through the contact layer, and then through the holes
connecting the sealant layer and collection chamber. In addition,
the series of openings located throughout the collection chamber
may allow for the distribution of pressure to the area of skin
trauma and reduce or prevent areas of localized pressure or fluid
build-up that may be greater in some areas and less in other
areas.
[0044] In some embodiments, the collection chamber further
comprises a one-way flow valve. The one-way flow valve may be used
to assist in the emptying of the collection chamber. The one-way
flow valve may also be used to re-create the reduced pressure, or
pre-evacuated, level of pressure inside the collection chamber. In
some embodiments, the one-way flow valve may be used to facilitate
both empting of the collection chamber and re-evacuation of the
collection chamber. The one-way flow valve may serves to facilitate
the re-evacuation of the collection chamber by facilitating the
attachment of a suction source to the collection chamber through
the valve and allowing the suction source to remove air molecules
from the collection chamber. The suction source may also be used to
remove exudate or air from the collection chamber through the use
of the one-way flow valve. In some embodiments, a first one-way
flow valve is used to empty the collection chamber and a second
one-way flow valve is used to re-evacuate the collection chamber.
In some embodiments, the one-way flow valve may be integrated with
the collection chamber. In some embodiments, the one-way flow valve
is attached to a removable plug used to occlude one end of the
collection chamber. In some embodiments, a plurality of one-way
valves may be provided, with one or more valves located in or
associated with the series of openings to reduce backflow of air or
material out of the collection chamber or the sealant layer and
back into the area of skin trauma. The one-way valves may have any
of a variety of configurations, including duckbill or flap
valves.
[0045] A segmented collection device or other multi-cavity device
may be used in place of a single chamber collection chamber in some
embodiments. A segmented collection chamber may comprise a first
chamber and a second chamber which may or may not be in fluid
communication with each other. In one example, the first chamber is
in direct communication with the sealant layer whereas the second
chamber is in communication with the first chamber. In embodiments
where a dual chamber collection chamber is used, one or more of the
segments or chambers may be a source of suction. The suction source
may comprise a non-powered or passive actuating and regulating
mechanism, including but not limited to a spring mechanism such as
a constant force spring. The passive actuating and regulating
mechanism may be used to apply and maintain a level of pressure
inside the sealed enclosure or space between the collection chamber
and the sealant layer. In some embodiments, the dual chamber
collection chamber comprises a reciprocating mechanism including,
but not limited to, a plunger. The plunger may be manually
distracted, or may be passively distracted, such as when attached
to a constant force spring. In some embodiments, the second chamber
expands the volume of air located in a joint volume of space shared
between the sealed enclosure and the dual chamber collection
chamber. One or segments or chambers may also comprise a powered or
active actuating and regulating mechanism.
[0046] In some embodiments, the system may also be sized or
configured to conform to the length of the surgically closed
incision. In some embodiments, the collection chamber conforms to
the length of the closed incision area of skin trauma by being
stretched to the length of the wound. In such an embodiment, the
collection can be made from a hydrocolloid material. Such a
material allows the collection chamber to be stretched to a new
desired length and remain at that length after the stress causing
the change in length has been removed. In such an embodiment, the
system may be made from a hydrocolloid or any suitable material. In
some embodiments, the system may be shortened to the length of the
closed incision. In some embodiments, the system can be cut to the
length of the closed area of skin trauma. In such an embodiment,
the cut end of the collection chamber may be self sealing upon the
application of pressure to the collection chamber. In some
embodiments, the collection chamber can be sealed after it has been
cut. In some embodiments, the collection chamber can be sealed with
an end cap, a plug, an occlusive sealant sheet, an end cap with a
one way flow valve, a constant force spring, a reduced pressure
system, or any suitable means for sealing the end of the collection
chamber. In one embodiment, the structure used to seal the end of
the collection chamber that has been adjusted to conform to the
length of the skin trauma is configured to resist removal once
affixed to the collection chamber. Alternatively, the structure
used to seal the end of the collection chamber that has been
adjusted to conform to the length of the skin trauma may be a
removable structure. In some embodiments, the system includes a
series of collection chambers lined up in parallel or serially with
each other. In such an embodiment, one or more collection chambers
may be removed from the series of collection chambers to
accommodate the width of the closed incision area of skin trauma.
In other embodiments, one or more collection chambers may be
replaced upon filling or clogging.
[0047] In some embodiments, the contact layer may be adjusted to
conform to the length of the surgically closed area of skin trauma.
For example, the contact layer may be lengthened or shortened based
upon the length of the closed incision or wound. In some
embodiments, the contact layer may be cut to the length of the
closed incision. In some embodiments, the collection chamber, the
contact layer, and/or the sealant layer may be adjusted to conform
to the length of the surgically closed incision. In some
embodiments, only the collection chamber is adjusted to conform to
the length of the incision before the system is placed on the
patient, while in other embodiments, only the contact layer or the
sealant layer is adjusted to conform to the length of the surgical
incision before the system is placed on the patient. In some
embodiments, the collection chamber, the contact layer, and the
sealant layer may each be individually adjusted to conform to the
length of the incision or wound before being placed on the patient.
In some embodiments, the collection chamber, the contact layer, and
the sealant layer are integrated together, such that the system is
adjusted to conform to the length of the surgically closed incision
or wound as a unit.
[0048] The system provided herein includes a sealant layer for
creating a seal with the surface of the patient. In some
embodiments, the seal is air tight. In some embodiments, the
sealant layer comprises a flexible impermeable material. In some
embodiments the sealant layer is a semi-rigid material. In an
embodiment where the sealant layer is a semi-rigid material, the
sealant layer may provide tensile support to the surgically closed
area of skin trauma. A semi-rigid sealant layer would further
alleviate mechanical tension on the surgically closed area of skin
trauma as the trauma heals.
[0049] In some embodiments, the system provided for herein further
includes absorbent beads. The absorbent beads are located in the
incision or wound, and/or the collection chamber. In some
embodiments, the system may comprise antimicrobial agents.
Antimicrobial agents include, but are not limited to, silver,
iodine, chlorhexidine or any other suitable antimicrobial
agent.
[0050] Some of the examples provided herein are configured to
create a level of pressure within the sealed enclosure encompassing
the surgically closed area of skin trauma. In some embodiments, the
level of pressure created is between about 0.001 and about 1 atm.
When in fluid communication with the enclosed space under the
sealant layer, the level of atmospheric pressure underneath the
sealant layer may be reduced to no lower than about 0.001 atm,
about 0.005 atm, about 0.01 atm, about 0.05 atm, about 0.1 atm,
about 0.2 atm, about 0.5 atm, about 0.7 atm, or about 0.9 atm. In
other embodiments, the atmospheric pressure underneath the sealant
layer may be reduced to about 0.8 atm or less, but in other
embodiments, may be reduced to less than about 0.7 atm, 0.6 atm,
about 0.4 atm, about 0.3 atm, about 0.2 atm, about 0.1 atm, about
0.07 atm, about 0.03 atm, about 0.007 atm, or to about 0.003 atm or
less.
[0051] In some embodiments, the contact layer, the sealant layer
and/or the collection chamber may be made from transparent
materials. The transparency of the materials may facilitate more
accurate placement of the system over the surgical incision or
wound by the clinician to more accurately place the system, and/or
may permit visualization of the incision or wound with breaking the
seal.
[0052] Also provided for herein is a method for applying a reduced
pressure therapy system to a surgically closed area of skin trauma.
The method comprises (a) sizing a collection chamber, a protective
layer and a sealant layer to a surgically closed area of skin
trauma; (b) forming a seal around the surgically closed area of
skin trauma; (c) activating the collection chamber to deliver
reduced pressure evenly distributed to the surgically closed area
of skin trauma; and (d) removing the system after
re-epithelialization of the surgically closed area of skin trauma.
Wound re-epithelialization occurs between 2 days and 5 days after
the skin trauma has been surgically closed. In some embodiments
wound re-epithelialization occurs 3 days after closure. In some
embodiments wound re-epithelialization occurs 4 days after closure.
In some embodiments wound re-epithelialization occurs 5 days after
closure. In some embodiments, wound re-epithelialization occurs
earlier than 5 days after wound closure. In some embodiments, wound
re-epithelialization occurs earlier than 4 days after wound
closure. In some embodiments, wound re-epithelialization occurs
earlier than 3 days following wound closure.
[0053] Further provided is a method for treating an area of skin
trauma using a reduced pressure therapy system, comprising: (a)
cutting a protective layer to the shape of an area of skin trauma;
(b) attaching the cut protective layer to an area of intact skin
surrounding the area of skin trauma; (c) cutting a flexible
adhesive dressing with an integrated layer of foam to a desired
size, said flexible adhesive dressing integrated with said layer of
foam in fluid communication with a flexible tubing; (d) placing the
dressing over said surgically closed area of skin trauma to form a
sealed enclosure; (e) configuring the tubing with an end piece; (f)
charging the device; (g) recharging the device as necessary to
remove exudates and to restore reduced pressure inside said
enclosure; and (h) removing the device after wound
re-epithelialization. In some embodiments the skin trauma is
selected from a cut, puncture wound, surgically created incision,
or any other wound which is suitable for being closed
surgically.
Devices
[0054] FIGS. 1A and 1B illustrate one embodiment static negative
pressure device 100. The device 100 comprises a sealant layer 110
and a collection chamber 120 configured to distribute pressure
along a surgical area of skin trauma, such as the length of a
surgical incision. In some embodiments, the negative pressure
therapy device may include a contact layer 130. The contact layer
130 provides fluid communication between the collection chamber 120
and the area of skin trauma. The contact layer 130 may comprise a
foam, mesh, gauze, sponge, particulate matter, a stacked mesh
matrix, or any other suitable porous biocompatible material, for
example. The contact layer 130 may be put into contact with the
surface of the surgically closed area of skin trauma. In some
instances, the contact layer 130 may be configured to maintain
continuity of the air/fluid spaces through the surgical site, which
may reduce the occurrence of isolated fluid or air pockets in the
enclosed space formed by the surgical area and the sealant layer
110. In some embodiments, the contact layer may be within the
borders the skin trauma surface and not contact, overlap or cover
the surrounding tissue area adjacent to the skin trauma. In other
embodiments, the contact layer may be placed in contact with the
adjacent tissue surrounding the skin trauma, in addition to the
region of skin trauma itself. As shown in FIG. 1A, the contact
layer 130, the sealant layer 110, and the collection chamber 120
may be coupled or integrated together. In some examples, a
pre-coupled or integrated design may permit the device 100 to be
placed in contact with the skin trauma surface in one step. In some
embodiments, the contact layer is placed in contact with the skin
trauma surface. Once positioned, the contact layer is then covered
by the sealant layer with an integrated collection chamber to form
a sealed enclosure or space. In some embodiments, the sealant layer
may be affixed to the area of skin surrounding the trauma area by
any suitable materials or mechanisms known to one skilled in the
art, including but not limited to, tape, glue, or a suitable
biocompatible adhesive product.
[0055] Further depicted in FIG. 1A is one example of a suction
apparatus 140. The suction apparatus 140 may be configured to
create a level of reduced pressure inside of the collection chamber
120. In some embodiments, the collection chamber 120 may be in a
pre-evacuated state prior to being positioned on the surface of the
skin trauma, while in other embodiments, the collection chamber 120
may be evacuated after positioning, or after coupling to the
suction apparatus 140. The collection chamber 120 may be
pre-evacuated at the point-of-use or at the point-of-manufacture.
In some embodiments, the suction apparatus may be coupled to the
collection chamber prior to being positioned on the surface of the
skin trauma, and in still other embodiments, the suction apparatus
and the collection chamber may be integrally formed. In some
embodiments the collection chamber may be sized to the length of
the surgically closed area of skin trauma by cutting the collection
chamber or by detaching or one or more portions of the collection
chamber. In some configurations, the collection chamber may have
one or more pre-defined separation zones with reduced thickness to
facilitate length reductions. A suction apparatus can then be
attached or otherwise used to close the cut or separated end of the
collection chamber. FIG. 1A shows the device 100 with a collection
chamber 120 in which a suction apparatus 140 comprises with a
constant force spring mechanism 142 has been integrated with the
collection chamber 120. When the constant force spring mechanism
142 of the suction apparatus 140 is engaged, the slidable seal or
reciprocating mechanism 144 may be drawn back to create and
maintain a constant level of pressure inside the sealed enclosure.
In FIG. 1A, the device 100 has been sized to the length of a wound
by cutting one end 122 of the collection chamber 120. FIG. 1A
further depicts the non-suction apparatus end 122 being occluded by
an end plug 124. The device is further sealed in FIG. 1A using an
end sealant structure 126. The non-suction apparatus end 122 and/or
the end plug 124 may be configured to detachable or non-detachable.
For example, a glue may be used to irreversibly attach the end plug
to the apparatus end 122.
[0056] In some embodiments, the length of the collection chamber
may be adjusted based upon the length of the surgical incision or
wound. The length of the surgical incision or wound may be
generally linear or may be non-linear. In some examples, the length
of the collection chamber is about the length of the surgical
wound, while in other examples, the collection chamber length may
be about +10%, about +20%, about +30% or more, about -10%, about
-20%, or about -30% or less than the length of the surgical wound.
Although generally elongate surgical wounds are contemplated, in
other examples, surgical wounds with non-elongate configuration may
also be treated. In some further examples, branching or stellate
surgical wounds may be treated, using one or more devices. In other
examples, the surgical wound or incision may be characterized as
the affected length of a partially dehisced surgical wound. In
examples where the surgical wound comprises a partially dehisced
surgical incision, the sealant layer and/or contact layer may be
configured to seal or cover the dehisced segment, or the entire
wound or incision. Exemplary methods for treating non-elongate
wounds are described later below. In some examples, the collection
chamber per cm length, may have a volume in the range of about 100
mm3 to about 10,000 mm3 or more, sometimes about 500 mm3 to about
7,000 mm3, and other times about 1,000 mm3 to about 5,000 mm3
[0057] The collection chamber 120 may be in fluid communication
with the skin trauma site through the contact layer 130 of the
device 100. In some examples, the collection chamber 120 and the
sealant layer 110 are integrally formed. As depicted in FIG. 1B,
the collection chamber 120 may comprise a plurality of openings 150
that may align or correspond to a plurality of openings 150' in the
sealant layer 110 to provide fluid communication between the skin
trauma and collection chamber 120 through the contact layer 130 and
the sealant layer 110. The series of openings 150 and 150' may
permit distribution of the pressure changes applied to the area of
skin trauma across the length or region of the skin trauma. The
spacing, size or shape of the openings 150 and 150' along the
collection chamber 120 and/or the sealant layer 110 may be uniform
or non-uniform. In other embodiments, the collection chamber 120
and the sealant layer 110 may comprise separate structures that are
configured for coupling. To facilitate alignment of the collection
chamber openings 150 with the openings of the sealant layer 110,
the adjacent surface of the collection chamber 150 and/or the
sealant layer 110 may comprise an adhesive or slip-resistant
surface. In other embodiments, the collection chamber openings 150
and/or openings in the sealant layer 120 may form complementary
interfit to facilitate alignment. For example, the collection
chamber openings 150 and/or the sealant layer openings 150'may
protrude into the opening in the corresponding structure. In still
other embodiments, the collection chamber openings 150 and the
sealant layer openings 150' may comprise complementary sealable
snapfit.
[0058] In some examples, the collection chamber may comprise an
elastically or plastically deformable material or a bendable
configuration. This may permit the collection chamber to conform to
the contours of a surgically closed area of skin trauma, and may
permit the collection chamber to exhibit at least some
conformational change in response to body movement. In one example
depicted in FIGS. 1A and 1B, the collection chamber 120 comprises
regions or zones of flexible ribbing 128 along the length of the
collection chamber 120. The ribbing 128 allows the collection
chamber 120 to be shaped and molded by the user and further
maintains the user defined configuration. The portions of the
collection chamber 120 between the flexible ribbing 128 may be
rigid, semi-rigid or flexible. In some further examples, a
collection chamber may also be configured to at least partially
rotate in addition to bending. In certain examples, different sizes
or configurations of openings may be provided around the
circumference of the collection chamber and may be selected for use
by rotation. The unused opening may be sealed by applying a sealant
layer over the unused openings. Alternatively, the openings may be
presealed and the selected seals may be utilized by removing the
pre-attached seal(s) from them.
[0059] FIG. 2 shows another embodiment of a negative pressure
therapy device 200 in which the device 200 is configured to be
re-evacuated or recharged. The device 200 comprises an integrated
contact layer 230, sealant layer 210 and collection chamber 220.
The contact layer 230 may be placed in contact with the surface of
the skin trauma and a seal may be formed between the skin
surrounding the skin trauma using the sealant layer 210. The
collection chamber 220 may be integrated with the sealant layer 210
and is in fluid communication with the contact layer and the
enclosed surgical site through a series of openings 250 in the
collection chamber 220 and the contact layer 230, but in other
examples, the collection chamber and the sealant layer may be
separated components that may be attached using adhesive or
mechanical mechanisms. With separate collection chambers and
sealant layers, the alignment of the collection chamber openings
and the sealant layer openings may be facilitated by configuring
either the collection chamber openings and/or the sealant layer
openings with complementary interfit designs. In one alternative
embodiment, the base sealant layer may lack pre-formed openings,
but the collection chamber openings may comprise sharpened or
penetrating structures to permit formation of sealant layer
openings when the two components are coupled together.
[0060] The collection chamber 220 may be in a pre-evacuated state
wherein a level of reduced pressure is already present inside.
Alternatively, the collection chamber 220 can be at atmospheric
pressure when placed on the patient, and a reduced level of
pressure can be created in the collection chamber using an external
evacuator device 270, such as a durable medical equipment
evacuator. The external evacuator device 270 may be positioned in
an opening 276 of an evacuator fitting 278 on the collection
chamber 220. The evacuator fitting 276 is in fluid communication
with the collection chamber 220. The evacuator fitting 276 may be
configured as a one-way flow valve that allows air molecules or
other materials to be removed from the collection chamber 220 while
resisting entry of air molecules or other materials into the
collection chamber. In the particular examples illustrated in FIG.
2, the collection chamber 220 comprises flexion regions 228 with
ribbing, but in other examples, a substantial length of the
collection chamber comprises a flexible material.
[0061] FIG. 2 also depicts a collection chamber 220 with one end
222 occluded with an end plug 224. The other end 222' of the
collection chamber may be fitted with a one-way flow valve 260.
Thus, the device 200 may comprise a separate one-way flow valve 260
for facilitating the emptying of the collection chamber 220 when
the collection chamber 220 is filled with exudate or other matter.
Once the collection chamber 220 has been emptied, the collection
chamber can then be re-evacuated using an external evacuator 270
introduced through the opening 276 of the evacuator fitting 278. In
some embodiments, the one-way flow valve 260 and the means for
evacuating the collection chamber 220 are the same structure. In
some embodiments, the one-way flow valve and the means for
evacuating the collection chamber are two different structures, as
shown in FIG. 2. FIG. 2 also shows a device 200 with a moldable
collection chamber 220.
[0062] Another example of a negative pressure therapy device 300 is
shown in FIG. 3. The negative pressure therapy device 300 may
comprise a multi-chamber collection system 370, comprising a first
chamber 372 and a second chamber 373. The multiple chambers may be
connected, or may be separate. In FIG. 3, for example the first and
second chambers 372 and 373 may be in fluid communication with each
other at an interconnecting opening 374. The first chamber 373 of
the dual chamber collection chamber 370 has a series of openings
350 that configured to provide fluid communication with the contact
layer 330 of the device 300. The second chamber 372 of the dual
chamber collection chamber 370 can be fitted with a reciprocating
mechanism for regulating pressure. In FIG. 3, the second chamber
the reciprocating mechanism is shown as a spring 374 attached to a
spring housing 378 on the end of the dual chamber collection
chamber 370 opposite to the sealed end with end plug 324. The
spring creates a moving seal 376 through the use of a plunger like
apparatus. The moving seal 376 self-regulates changes in pressure
in the dual chamber collection chamber 370 and moves in response to
these changes.
[0063] FIG. 4 illustrates another embodiment of a negative pressure
therapy device 400, in which contact layer 430, the collection
chamber 420, and the sealant layer 410 of the device are not
integrated and the sealant layer 410 is placed above or over the
collection chamber 420 and contact layer 430. In this embodiment,
the contact layer 430 is placed in contact with the surgically
closed area of skin trauma. A moldable collection chamber 420 with
ribbing 428 to may be used to manipulate configuration of the
chamber 420 for contact and coverage with the contact layer 430. A
series of openings 450 located in the collection chamber 420
provides for fluid communication between the contact layer 430 and
the collection chamber 420. The collection chamber 420, once in
contact with the contact layer 430, may then be evacuated through
the use of suction apparatus 440. The suction apparatus can be a
syringe, a powered pump, or a forced expansion device. The suction
apparatus 440 is preferably in fluid communication with the
collection chamber 420 through a one-way valve 460. After the
collection chamber 420 is evacuated, a sealant layer 410 can then
be placed over the collection chamber 420 and the contact layer 430
to form a sealed enclosure with the wound.
[0064] FIG. 5 depicts another embodiment of a device 500, in which
the collection chamber 520 comprises corrugated tubing segments 582
with discrete collection members 580 interspersed throughout the
collection chamber 520. One end 522 of the corrugated tubing is
sealed with an end plug 524 or other closed configuration. The
other end 522' of the device 500 may be coupled or integral with a
suction source 540, such as a constant force spring, a powered
suction pump, a durable medical equipment evacuator, or any
suitable suction source. The contact layer 530 of the device 500 is
integrated with the sealant layer 510 and the collection chamber
520 in FIG. 5. Once placed on the patient, the corrugated tubing
segments 582 allow the collection chamber to conform to the surface
topology of the patient. This embodiment of the device allows the
device to move with the patient. The corrugated tubing segments
allows for significant expansion and compression of the underlying
skin. In an embodiment where the collection chamber is a corrugated
tube with discrete collection members, the discrete collection
member 580 are in preferably fluid communication with the contact
layer 530 and skin trauma surface through a series of discrete
openings 550.
[0065] In some embodiments, an elongate reduced pressure therapy
system may be applied along the length of an elongate wound with
wound edges that may be approximated. The elongate reduced pressure
therapy system may also be used with incisions already closed by
sutures, staples or adhesives, for example. In some instances, the
use of a reduced pressure therapy system on a closed incision may
provide more uniform force distribution along an incision, by
exerting additional closure forces against tissues not immediately
contacting a suture or staple, for example. A negative pressure
therapy system, in some instances, may also resist separation of
the wound edges. In some instances, the negative pressure therapy
system may resist stretching of the newly formed connective tissue,
which may reduce the extent of scarring. In some examples, by
applying a sealant layer and reducing the pressure, the
approximation of the wound edges may be further augmented by
collapsing the potential space between the edges. In some
particular embodiments, the wound treatment system may comprise a
negative pressure system that is configured to provide both
mechanical tension reduction and reduced pressure effects on the
incision or wound. The reduced pressure effects may or may not
include the displacement of the wound edges toward each other by
reducing the pressure of the space between the wound edges and/or
from pushing or pulling by the sealant layer as the sealant layer
is contracted around the support. A reduced pressure therapy system
may also comprise an elastic sealing layer or a sealing layer
configured with one or more elastic members. In use, the sealant
layer may be attached or adhered to one side of the incision or
wound and then stretched and attached to the other side of the
incision or wound. Once in place and with the stretching force
relieved, the sealant layer or its elastic member may exert
opposing forces on each side of the wound to augment the edge
approximation and draw the incision or wound edges together. In
some examples, the elastic members may be oriented in a transverse
position to the longitudinal orientation of the incision or wound,
but in other examples, the elastic member may be oriented in
multiple directions. The sealant layer or the elastic member may
comprise a material such as silicone rubber, polyisoprene or other
elastomeric material which possesses a sufficient restoring force
to pull tissue together when adhered to opposing incision or wound
edges in a stretched configuration. In some examples, one or more
elastic members may be applied or attached to the sealant layer
after the sealant layer has been applied to the incision site or
wound site.
[0066] FIGS. 6A to 6C depict another example of a wound treatment
device 600 comprising a sealant layer 602 and an elongate support
604. The elongate support 604 may be configured with an elongate
central channel 606 that may be placed along or over an incision or
elongate wound. In some configurations, the device 600 may comprise
multiple channels in direct communication with the elongate wound.
In this particular example, the elongate central channel 606 has an
open channel configuration that is exposed to the incision or wound
along a portion if not all of its longitudinal length, but in other
examples, the elongate channel 606 may have a generally closed
configuration with a plurality of longitudinally arranged openings
along a segment of the channel or the entire channel. An open
channel or a plurality of longitudinally arranged openings may
permit the application of reduced pressure along a length of the
wound while possibly reducing the risk that clogging or transient
opposition of tissue surfaces may affect the distribution of
pressure reduction and/or fluid suction. In some examples, the
channel, or the segment of the channel in communication with the
incision or wound, may have a length of at least about 1 cm or
more, 3 cm or more, sometimes about 10 cm or more, and other times
about 20 or about 50 cm or more. In some examples, the device 600
may comprise a length of about 70 cm, 100 cm or even 150 cm, which
may be cut or shortened to a smaller length. In some embodiments
comprising a flexible, bendable and/or moldable support 604, the
support 604 and/or sealant layer 602 may be provided in the form of
a roll or a folded form, which is then dispensed and cut as needed.
The device 600 (or other devices described herein) may be used to
treat any of variety of incisions or wounds, but in some specific
examples may be used to a variety of elongate incisions or wound,
including but not limited to linear or curvilinear incisions or
wounds. These wounds may include but are not limited to any of a
variety of traumatic lacerations or cuts, sternotomy incisions,
laparotomy incisions, perineal prostatectomy incisions, vein
harvesting incisions, C-section incisions, and the like.
[0067] In use, the elongate central channel 606 may be positioned
along an incision or elongate wound and then secured or sealed by
placing the sealant layer 602 over the incision and support 604.
The sealant layer 602 and the support 604 may be integrally formed
or pre-attached to each other, such that the sealant layer 602 and
the support 604 may be applied to an incision or wound in a single
step. In some examples, the sealant layer 602 may have a size and
configuration to permit complete sealing of the entire perimeter of
the incision and the support 604, but in other examples, one or
more accessory seals 608 and 610 may be used. The sealant layer 602
may comprise an adhesive on one or more surfaces. In FIG. 6A, for
example, adhesive may be provided along the lateral regions the
undersurface of the sealant layer 602, leaving a strip or middle
section of the sealant layer 602 free of adhesives. In this
particular example, end seals 608 and 610 may be used to facilitate
sealing about the ends 612 and 614 of the sealant layer 602, but in
other embodiments, accessory seals may be used anywhere to provide
additional sealing.
[0068] In some examples, the sealant layer, support, and/or one or
more accessory seals may be pre-configured with a connector or port
which may be used to coupled the device 600 to a reduced pressure
source. In the particular example in FIG. 6A, one of the end seals
610 is pre-configured with a connector 616 that may be used to
attach a suction device 618 using an optional connector tube 620.
In other examples, the suction source or a connector tube may be
configured to pierce and form an aperture through the sealant layer
or accessory seal. In still other examples, the suction device 618
may be integrally formed with the end seal, sealant layer and/or
support 604.
[0069] As shown in FIG. 6B, the support 604 may optionally comprise
one or more side flanges or flaps 622 to one or both sides of the
elongate channel 606. Each of the side flaps 622 may have a width
(or dimension transverse to its longest dimension) in the range of
about 2 mm to about 50 mm or more, sometimes about 10 mm to about
40 mm, and other times about 20 mm to about 30 mm The side flaps
may have an average thickness in the range of about 0 5 mm to about
5 mm or more, sometimes about 0.75 mm to about 3 mm, and other
times about 1 mm to about 2 mm The thickness of the side flap may
or may not be uniform, and in some examples, the thickness may
taper or reduce in a central to peripheral direction, or vice
versa. The side flaps 622 may comprise the same or different
material as the material about the elongate channel 606. In some
embodiments, the support 604 and/or the side flaps 622 may be
rigid, semi-rigid or flexible, and may comprise silicone, urethane,
or the like, and may or may not comprise a coating. For example,
one or more sections of the support 604 may comprise an
ant-infective coating, including but not limited to a silver alloy
or chlorhexidine coating. The side flaps 622 may or may not
comprise an adhesive on its tissue contacting surface 624 and/or
its sealant layer contacting surface 626. In some examples, the
support 604 may further comprise a cap structure 628. The cap
structure 628 may be located on the upper surface of the elongate
channel 606 and may be configured to project to one or both sides
of the elongate channel 606. The cap structure 628 may project
anywhere from about 0 mm to about 15 mm or more, sometimes up to
about 5 mm, and other times up to about 10 mm In some examples, one
or more elongate side channels 630 may be formed between the cap
structure 628 and the side flanges or flaps 622. The cap structure
628 may comprise rounded edges or surfaces, which may or may not
reduce the risk of puncturing or damaging the sealant layer when
contracted onto the support 604. In some examples, an accessory
seal, or a sealant layer configured with regions of greater
thickness, puncture resistance, or other reinforcement may be
positioned about the support 604. The side flaps 622 and/or the cap
structure 628 may or may not have a symmetrical configuration
and/or size with respect to the elongate channel 606. In some
configurations, one or more openings may be provided in the walls
632 between the central channel 606 and the side channel(s) 630,
but in other configurations, communication between the central
channel 606 and the side channel(s) 630 may only occur about the
ends of the support 604 where the sealant layer 602 may provide a
common space or pocket where it may not be adhered to the skin.
[0070] As shown in FIG. 6C, when reduced pressure is applied to the
device 600, the sealant layer 602 may collapse around or into the
support 604. For example, sections of the sealant layer 602 may be
pulled or pushed into the elongate side channels 630. In other
examples, the support 604 may comprise any of a variety of
indentations, openings, grooves, channels which may permit
contraction of the sealant layer 602 to the support 604, either
with suction or by mechanical structures such as a clamp or
pushrod, drawstring or any other complementary structure that may
be attached or coupled to tighten the sealant layer 602 to the
support 604. In some instances, this contraction of the sealant
layer 602 may or may not draw the wound edges 634 closer together.
The application of reduced pressure may also reduce the size or
eliminate the gap 636 between the wound edges 634.
[0071] In addition to the support, the wound treatment system may
also comprise one or more elastic elements incorporated or
attachable to the sealant layer. For example, elastic bands or
threads may be provided in the sealant layer in addition to the
elastic properties of the support, if any. In some configurations,
the elastic bands or threads may have a uniform orientation, but in
other configurations, the elastic bands may be oriented in multiple
directions. In some instances, the support may also comprise an
elastic material or structure (e.g. a spring) which may be
configured to further mechanically bias the wound tissue or edges
in a particular direction. In some instances, the spring may
comprise an attachable clip, which is optionally used with the
support to provide additional force with elastic supports, or the
contracting force with rigid supports.
[0072] In some examples, the reduce pressure wound therapy system
may be used to treat incisions or elongate wounds that may be
longer than the length of the device that is available. In such
situations multiple devices, supports and sealant layers may be
arranged in an independent or an overlapping configuration to treat
larger wounds. In FIG. 7, for example, two separate supports 700
and 702 and sealant layers 704 and 706 are positioned end-to-end
and the junction region 708 is covered with a third sealant layer
710. Use of a third sealant layer 710 may be useful, for example,
where the support and sealant layer are supplied or manufactured in
an integral or pre-attached configuration. Although the ends of the
supports 700 and 702 and the sealant layer 704 and 706 are depicted
as touching at the junction region 708, in other examples, partial
or full gaps may be provided between supports and/or sealant
layers. In addition to the serial configuration depicted in FIG. 7,
the supports and/or sealant layers may also be arranged in a
parallel fashion. In other examples, a third sealant layer need not
be used, as one sealant layer may be overlapped over another where
the sealant layer extends past the end of it associated support. In
other examples, multiple sealant layers or supports may be provided
and used with a lesser number of supports or sealant layers,
respectively. Also, more than one suction device may be used with
longer or larger support or sealant layers.
[0073] In addition to multiple supports that may be arranged in a
parallel and/or serial fashion, in some embodiments, the supports
themselves may comprise multiple sections that are joined together
to form a complete support. In FIG. 8, for example, a support 800
comprise two elongate support segments 802 and 804 which are
configured to be generally joined along their longitudinal lengths
at a coupling interface 806. A support 800 comprising separate
longitudinal segments 802 and 804 may be used to separately attach
each segment 802 and 804 to one edge of an incision or wound (e.g.
by adhesives or suturing) and are then joined together to
approximate the wound edges. In some instances, separate joinable
components may be easier to attach to the skin than a unibody
support. The longitudinal segments 802 and 804 may be rigid,
semi-rigid or flexible, and although the segments 802 and 804 are
depicted as each contributing about 50% of the structure, e.g.
generally symmetrically split except for possibly the coupling
interface. In other examples, however, the longitudinal segments
may be asymmetrically split. The coupling interface 806 depicted in
FIG. 8 comprises a complementary set of grooves 808 and ridges 810
located along the longitudinal inner surface 812 of each segment
802 and 804, but any of a variety of coupling interfaces 806 may be
used, including other snapfits. Other locking interfaces,
mechanisms or structures may include but are not limited to
resealable adhesive layers, slide locks, hinge clamps, clips,
locking pins with lockable lumens, zippers, elastic binding bands,
and the like. In some examples, structures that may be used to
contract the sealant layer into a unibody support may also be used
to contract the sealant layer into a multi-segment support and/or
to couple the segments of a multi-segment support together.
[0074] FIG. 9A depicts one example of a negative pressure therapy
system 900 comprising an elastic support 902 and an optional
suction system 904. An optional contact layer 906 may be provided
under the elastic support 902. The elastic support 902 is
configured with one or more longitudinal conduits 908 or channels.
The conduit or channel may be fully enclosed or may be at least
partially open. The conduit 908 in FIG. 9 has a closed
configuration with a plurality of apertures 910 to permit air or
fluid communication with the underlying wound or incision. In this
particular example, the lateral flaps 912 of the elastic support
904 may comprise an adhesive, which may be used to at least seal a
portion of the conduit 908 and the external space, if any, between
the incision or wound and the apertures 910. In some other
examples, the lateral flaps 912 may extend to one or both ends of
the support, but in the example, depicted in FIG. 9A, end seals 914
and/or 916 may be used to facilitate sealing about the ends 918 and
920 of the support 902. As mentioned previously, at least one of
the end seals 916 may be provided with a connector 922 for
attachment of the suction system 904, but in other embodiments, the
connector may be located on the elastic support 902. In still other
examples, a large sealant layer may be used to cover a larger
portion if not all of the support, and with or without a protective
layer. For example, some embodiments of the elastic support may
comprise segmented non-sealing lateral flaps which are configured
to elastically bring wound edges together. The segmentation may
facilitate the application of the elastic support in a sectional
manner, but may or may not provide sealing ability, such that a
sealant layer applied over the elastic support may be used to
provide a sealed space about the support.
[0075] Referring to FIGS. 9B to 9D, in use, the flaps 912 of the
elastic support 902 may be elastically stretched or pulled away
from each other and applied in its stretched state to the incision
or wound such that each flap 912 is adhered to the skin surface 922
to a respective edge of the incision or wound. In some procedures,
the support 902 may be sufficient stiff or rigid such that a
substantial longitudinal length of the flaps 912 can be stretched,
but in other configurations, a smaller portion of the flaps 912 may
be pulled away, which may facilitate the application of the support
to non-linear incisions or wound by permitting adherence or
attachment of the support section-by-section. Once adhered to the
skin surface 920, the stretching or deformation force may be
relieved, and the elasticity or bias in the support 904 may push
the wound edges 922 toward each other. Once fully sealed, the
suction source 904 may be activated to reduce the pressure in the
conduit 906 and/or to remove air or fluid from the incision or
wound, which may or may not further reduce the gap 924, if any,
between the wound edges 922, in addition to providing a reduced
pressure to enhance healing and/or to evacuate potential fluid
pockets. FIG. 9E depicts how two elastic supports 902 with flaps
912 may be positioned serially or in an end-to-end fashion to treat
incisions or wounds having a longer length by covering the junction
958 with an accessory seal 960. As noted previously, although the
ends of the supports 902 and their flaps 912 are depicted as
touching at the junction region 958, in other examples, partial or
full gaps may be provided between supports and/or their flaps.
[0076] The elastic support may comprise any of a variety of
configurations. As depicted in FIGS. 9B to 9D, the elastic support
902 may comprise an elastomeric member 926 which may augment the
elastomeric properties, if any, of the flaps 912 and/or wall 928 of
the conduit 908. As further illustrated, the apertures 910 of the
elastic support 902 may be provided directly in the elastomeric
member 926, and in some configurations the apertures 910 may also
deform in shape when force is applied to the flaps 912. FIG. 10A to
10C depicts another embodiment of an elastic support 950 with flaps
952, wherein the apertures 954 are provided in a non-elastic
structure 956. Thus, when the elastomeric member 958 is stretched,
the apertures 954 maintain the same configuration. The non-elastic
structure 956 may have any of a variety of configurations,
including rings or frames, and may form either a partial or a
complete perimeter of the aperture 954. The non-elastic structures
956 may be separate for each aperture 954 or they may be
interconnected. FIG. 11A to 11C depicts still another embodiment of
an elastic support 970 with flaps 972 comprises an elastic material
such that a specific elastomeric member is not used. In this
particular embodiment, the elastic support 970 comprise an open
channel 974 that lacks discrete apertures and instead is generally
open along the length of the channel 974 to the edges 922 and space
924 of the underlying incision or wound. As shown in FIGS. 11A to
11C, the elastic support 970 may be applied to an incision 976
closed with sutures 978 or other type of incision closure such as
staples. The sutures 978 may any type of suture and may be used
with any of a variety of suture techniques, including running
sutures and interrupted sutures. In some variations, although the
sutures 978 may generally maintain the approximation of the wound
edges 980, separation forces acting at the sutures 978 may generate
focal regions of tissue tension. Application of the elastic support
970 to the incision may be used to apply additional contiguous
force along a substantial length of the incision 976, which may or
may not reduce the focal tissue tension and possibly improve
incision healing.
[0077] In other embodiments, the devices described herein may also
be used to treat non-elongate incisions or wounds. FIGS. 12 to 15
depict various examples of using an elongate negative pressure
therapy system to treat non-elongate wounds. In FIG. 12, for
example, an elongate negative pressure therapy device 1000 and a
sealant layer 1002 are positioned around the perimeter of wound
1004. As further illustrated in this example, the device 1000 may
comprise apertures 1006, 1008 and 1010 of varying size. In some
instances, smaller apertures 1004 may be used at distances closer
to the suction source or interface 1012, while larger apertures
1008 may be used at relatively farther distances. In still other
examples, the size of the apertures may be uniform, but either the
number and/or the spacing of the apertures may vary along the
longitudinal length of the device.
[0078] FIG. 13 depicts another example of a negative pressure
therapy device 1020 arranged in a spiral orientation with respect
to a wound 1022. In some instances, the spiral orientation may
augment the pressure or suction about the center of the wound 1022,
compared to the device arranged depicted in FIG. 12. FIG. 14 is
still another example of a device 1030 comprising alternating rigid
sections 1032 and flexion sections 1034 arranged in a
back-and-forth or zig-zag orientation along a non-elongate wound
1036. As mentioned previously, in some examples, the rigid sections
1032 may also rotate with respect to the flexion section 1034 or
other articulation of the device. As shown in FIG. 13, the device
need not be fully located within the borders of the wound 1036, and
although all of the device apertures 1038 are located within the
wound borders, in other examples one or more apertures may be
located outside the border of the wound.
[0079] FIG. 15 depicts another example where multiple devices 1040
and sealant layers 1042 are used to close a non-linear surgical
incision. In this particular embodiment, the surgical incision
comprising a T-incision with a transverse incision 1044 and a
midline incision 1046, and is treated using two open-channel
devices 1040 applied to each incision 1044 and 1046, with
overlapping sealant layers 1042. In other examples, more than two
devices and two sealant layers may be used, e.g. one longer device
may be used along the entire length of the midline incision 1046
and two smaller devices may be used along each remaining segment of
the transverse incision 1044. In some instances, open channel
devices 1040 may be used when surgical close is performed with
staples 1048 or any other protruding closure component.
[0080] While a number of embodiments have been shown and described
herein, one of skill in the art will understand that these
embodiments are provided by way of example only. Numerous
variations, changes, and substitutions may be made those skilled in
the art without departing from the invention. It should be
understood that various alternatives to the embodiments described
herein may also be employed. It is intended that the following
claims define the scope of the invention and that methods and
structures within the scope of these claims and their equivalents
be covered thereby. For all of the embodiments described herein,
the steps of the methods need not be performed sequentially.
* * * * *