WO2021165820A1

WO2021165820A1 - Extremity dressing with collapsible cuff for negative pressure wound therapy

Info

Publication number: WO2021165820A1
Application number: PCT/IB2021/051269
Authority: WO
Inventors: Christopher Brian Locke; Thomas Alan EDWARDS
Original assignee: Kci Licensing, Inc.
Priority date: 2020-02-17
Filing date: 2021-02-15
Publication date: 2021-08-26

Abstract

A negative pressure wound therapy system includes a pump and a dressing fluidly communicable with the pump. The dressing includes a treatment portion configured to receive an extremity of a patient and a cuff positioned at a first end of the treatment portion and configured to extend around the extremity of the patient. The pump is operable to remove air from an interior of the cuff. The cuff is configured to contract circumferentially when the air is removed from the cuff.

Description

EXTREMITY DRESSING WITH COLLAPSIBLE CUFF FOR NEGATIVE PRESSURE

WOUND THERAPY

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority to U.S. Provisional Application No.

62/977,483, filed on February 17, 2020, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The present invention relates generally to the field of treating wounds (e.g., bums, lacerations, surgical incisions, sores, ulcers, damaged tissue, nerve damage, etc.) and more particularly to negative pressure wound therapy systems with instillation therapy. Negative pressure wound therapy refers to the application of negative pressure (relative to atmospheric pressure) to a wound bed to facilitate healing of the wound bed. Negative pressure may be applied in coordination with instillation therapy, in which instillation fluid (e.g., cleansing fluid, medicated fluid, antibiotic fluid, irrigation fluid) is applied to the wound bed. Negative pressure and instillation wound therapy (NPWTi) may facilitate removal of wound exudate and other debris from the wound bed and otherwise support healing.

[0003] One common location for a wound (e.g., a bum) that could benefit from NPWTi is on a patient’s hand. However, standard NPWTi dressings may be challenging to use on a hand due to the shape, size, contours, articulation, etc. of a hand. Accordingly, hand-specific dressings may facilitate improved NPWTi for hand wounds.

SUMMARY

[0004] One implementation of the present disclosure is a negative pressure wound therapy system.

The negative pressure wound therapy system includes a pump and a dressing fluidly communicable with the pump. The dressing includes a treatment portion configured to receive an extremity of a patient and a cuff positioned at a first end of the treatment portion and configured to extend around the extremity of the patient. The pump is operable to remove air from an interior of the cuff. The cuff is configured to contract circumferentially when the air is removed from the cuff.

[0005] In some embodiments, the cuff is configured to provide a seal between the cuff and the extremity when the cuff extends at least partially around the extremity and the air is removed from the cuff.

[0006] In some embodiments, the cuff includes an external film layer and an internal film layer sealed to the external film layer along a periphery of the cuff to define the cuff. An interior volume of the cuff is defined by the external film layer and the internal film layer. A manifold layer may be positioned in the interior volume of the cuff and sealed between the external film layer and the internal film layer. An adhesive layer may be coupled to the internal film layer with the internal film layer positioned between the manifold layer and the adhesive layer. In some embodiments, the adhesive layer is perforated and comprises silicone.

[0007] In some embodiments, the cuff includes a manifold layer extending along a circumference of the cuff. The manifold layer may include a foam material having a plurality of diamond-shaped cut outs. In some embodiments, the interior of the cuff comprises a manifold layer having a length defining a circumference of the cuff and a width defining a thickness of the cuff. When the air is removed from the cuff by the pump, the length of the manifold layer is reduced by a first percentage and the width is reduced by a second percentage. The first percentage is preferably greater than the second percentage. For example, the first percentage may be at least four times greater than the second percentage.

[0008] In some embodiments, the treatment portion is glove-shaped. In some embodiments, the negative pressure wound therapy system includes a tube extending from the pump and fluidly communicable with the interior of the cuff via a connection pad positioned on an external surface of the cuff. The pump may be operable to remove air from a volume defined by the treatment portion when the seal is established between the cuff and the extremity. The negative pressure wound therapy system may include a valve positioned between the cuff and the treatment portion. The valve is configured to prevent airflow between the interior of the cuff and the treatment portion when a negative pressure in the cuff is at less than a threshold absolute value and allow airflow between the interior of the cuff and the treatment portion when the negative pressure in the cuff is at greater than the threshold absolute value.

[0001] In some embodiments, the treatment portion includes an external film layer, a manifold layer, and a wound contact layer.

[0002] Another implementation of the present disclosure is a method of treating a wound at an extremity of a patient. The method includes providing a dressing that includes a treatment portion and a cuff positioned at a first end of the treatment portion, inserting the extremity of the patient through the cuff and into the treatment portion, and establishing a seal between the cuff and the extremity by providing a pump in pneumatic communication with the cuff and operating the pump to remove air from the cuff to cause the cuff to contract circumferentially.

[0003] In some embodiments, the method also includes operating the pump to remove air from a space between the treatment portion and the extremity to provide a negative pressure to the extremity at the treatment portion. In some embodiments, the method includes adhering the cuff to the patient using an adhesive coupled to the cuff.

[0004] In some embodiments, operating the pump to remove air from the cuff to cause the cuff to contract circumferentially includes causing a manifold layer of the cuff to contract. The manifold layer is provided with a plurality of cut-outs configured to facilitate contraction of the manifold layer. The cut-outs may be diamond-shaped. [0005] Another implementation of the present disclosure is a cuff for a wound therapy system. The cuff includes a first film formed as a loop, a second film concentric with the first film and sealed to the first film to define a volume between the first film and the second film, and a foam structure positioned in the volume between the first film and the second film. The foam structure is configured to reduce in length when a negative pressure is established in the volume. A reduction in length of the foam structure causes a reduction in circumference of the loop.

[0006] In some embodiments, the foam structure includes a plurality of holes therethrough configured to facilitate the reduction in length of the foam structure. In some embodiments, the plurality of holes are diamond-shaped.

[0007] In some embodiments, the cuff also includes an adhesive positioned on a surface first film outside of the volume. In some embodiments, the cuff also includes a port positioned at the second film and configured to be coupled to a tube.

[0008] In some embodiments, the cuff is configured to be coupled to a treatment portion of a dressing. The cuff may include a valve configured to regulate fluid communication between the treatment portion and the volume.

[0009] In some embodiments, when the negative pressure is applied, the reduction in length of the foam structure is greater than a reduction in width of the foam structure. In some embodiments, when the negative pressure is applied, the reduction in length of the foam structure is greater than a reduction in thickness of the foam structure.

[0010] Another implementation of the present disclosure is a dressing. The dressing includes a first film coupled to a second film. The first film includes a substantially air-impermeable polyurethane. The second film includes a plurality of structures formed on a surface of the second film facing the first film. The structures provide an open volume between the first film and the second film. The open volume allows fluid to flow between the first film and the second film.

[0011] In some embodiments, the second film includes a plurality of fenestrations configured to allow the fluid to flow across the second film. The first film and the second film may be arranged to form a glove. The first film defines an exterior of the glove. In some embodiments, the second film layer includes a palm region and a plurality of digit regions extending from the palm region. The digit regions include thermoformed folds configured to facilitate bending of the digit regions. The plurality of structures may include channels formed on the second filmi at the digit regions. The channels may be zig-zag shaped.

[0012] In some embodiments, the dressing includes a third film coupled to the second film and configured to contact a wound of a patient when the dressing is applied to the wound. In some embodiments, the second film includes a first set of fenestrations and the third film includes a second set of fenestrations. The first set of fenestrations may be aligned with the second set of fenestrations. [0013] Another implementation of the present disclosure is a negative pressure wound therapy system. The system includes a pump and a dressing fluidly communicable with the pump. The dressing includes a first film configured to define an air-tight volume between the first film and an anatomical feature when coupled to the anatomical feature. The dressing also includes a second film coupled to the barrier film so as to be positioned in the air-tight volume. The second film includes a plurality of structures formed on a surface of the second film. The surface faces the first film. The pump is operable to remove air from the air-tight volume via pathways between the first film and the second film. The pathways are provided by the structures.

[0022] In some embodiments, the structures are configured to provide the pathways by at least partially preventing the first film from sealing against the TPU film when air is removed from the dressing by the pump. In some embodiments, the second film includes a plurality of fenestrations configured to allow the fluid to flow across the second film. In some embodiments, the first film and the second film are transparent. The first film and the second film may be arranged to form a glove, with the first film defining an exterior of the glove.

[0023] In some embodiments, the second film layer includes a palm region and a plurality of digit regions extending from the palm region. The digit regions include thermoformed folds configured to facilitate bending of the digit regions. The plurality of structures may include channels formed on the second film at the digit regions. The channels may be formed with zig-zag-shaped wall structures. [0024] In some embodiments, the dressing includes a third film coupled to the second film and configured to contact a wound of a patient when the dressing is applied to the wound. The second film may include a first set of fenestrations and the third film may include a second set of fenestrations. The first set of fenestrations may be aligned with the second set of fenestrations. In some embodiments, the first film, the second film, and the third film are transparent.

[0025] Another implementation of the present disclosure is a method of treating an extremity wound. The method includes applying a dressing over the extremity wound, the dressing comprising a transparent manifold film having a plurality of structures protruding therefrom and a transparent barrier film, coupling the dressing to a negative pressure wound therapy unit, applying negative pressure to the dressing, and inspecting a condition of the extremity wound through the transparent manifold film and the transparent barrier film with the dressing intact over the extremity wound. [0026] In some embodiments, the dressing includes a transparent wound contact film. The method includes inspecting the condition of the extremity wound through the transparent manifold film, the transparent barrier film, and the transparent wound contact film with the dressing intact over the extremity wound. The method may also include communicating the negative pressure to the extremity wound via a first set of fenestrations in the transparent manifold film and a second set of fenestrations in the transparent wound contact film. The first set of fenestrations are aligned with the second set of fenestrations.

[0027] In some embodiments, the method includes modifying operation of the negative pressure wound therapy unit based on the condition of the extremity wound. The method may also include removing the dressing upon the condition of the extremity wound reaching a predetermined state. The method may also include supplying instillation fluid to the extremity wound via an open volume between the transparent barrier fdm and the transparent manifold film. The open volume is defined by the plurality of structures.

[0028] In some embodiments, applying the negative pressure to the dressing includes forming a plurality of channels between the transparent barrier film and the transparent manifold film, the channels defined by the plurality of structures.

[0029] Another implementation of the present disclosure is a dressing. The dressing includes a barrier film layer, a wound contact layer coupled to the barrier film layer, and a plurality of felted foam strips positioned between the barrier film layer and the wound contact layer. Each strip provides a manifolding pathway. The barrier film layer and the wound contact layer include a central region and a plurality of peninsular projections extending therefrom in the shape of a hand.

[0030] In some embodiments, each strip extends from the central region to one of the plurality of peninsular projections. The dressing can include a felted foam pad positioned at the central region, with the plurality of strips extending from the felted foam pad. The felted foam strips may be configured to allow airflow between the peninsular region and the felted foam pad. The dressing can include a connection assembly coupled to the barrier film layer at the felted foam pad. The connection assembly is configured to provide airflow between the felted foam pad and a tube coupled to the connection assembly.

[0031] In some embodiments, the barrier film layer and the wound contact layer are configured to form wrinkles therein when air is removed from the dressing via the felted foam strips. The wrinkles can allow fluid to flow therethrough.

[0032] In some embodiments, the felted foam strips include an open-cell foam. The wound contact layer and the barrier film layer may be configured to allow visual observation of a wound through the wound contact layer and the barrier film layer.

[0033] In some embodiments, the barrier film layer is welded to the wound contact layer around a perimeter of the barrier film layer and at a plurality of spot welds distributed amongst the plurality of felted foam strips. The spot welds constrain movement of the plurality of felted foam strips relative to the barrier film layer and the wound contact layer.

[0034] In some embodiments, the barrier film layer, the wound contact layer, and the plurality of felted foam strips are formed as a first side of a glove assembly. The first side of the glove assembly is coupled to a second side of the glove assembly to form the glove assembly. The second side of the glove assembly may include a second barrier film layer, a second wound contact layer coupled to the second barrier film layer, and a plurality of second felted foam strips positioned between the barrier film layer and the wound contact layer. Each strip provides a manifolding pathway. The dressing may include a felted foam cuff fluidly communicable with the plurality of felted foam strips of the first side and the plurality of second felted foam strips of the second side. [0035] In some embodiments, the glove assembly is configured to receive a hand of a patient between the wound contact layer and the second wound contact layer. The dressing may include an adhesive configured to seal the first the first side and the second side to a wrist of the patient when the glove assembly receives the hand. The barrier film layer and the second barrier film layer provide a substantially airtight volume therebetween when the adhesive is sealed to the wrist of the patient. [0036] Another implementation of the present disclosure is a wound therapy system. The wound therapy system includes a pump, a tube coupled to the pump, and a glove-shaped dressing coupled to the tube. The glove shaped dressing includes a barrier film layer, a wound contact layer coupled to the barrier film layer, and a plurality of felted foam strips positioned between the barrier film layer and the wound contact layer. The barrier film layer and the wound contact layer include a central region and a plurality of peninsular projections extending therefrom in the shape of a hand. Each of the plurality of felted foam strips extend from the central region to one of the plurality of peninsular projections.

[0037] In some embodiments, the felted foam strips are fluidly communicable with the pump via the tube. The pump is configured to draw a negative pressure at the felted foam strips. The barrier film layer and the wound contact layer may be configured to form wrinkles when the pump draws the negative pressure at the felted foam strips. The wrinkles can allow airflow therethrough. In some embodiments, the barrier film layer and the wound contact layer are configured to allow a wound to be visually observed therethrough.

[0038] In some embodiments, the wound therapy system includes a felted foam pad positioned at the central region. The plurality of felted foam strips extend from the felted foam pad and the tube is coupled to the glove-shaped dressing proximate the felted foam pad.

[0039] Another implementation of the present disclosure is a method. The method includes inserting a hand of a patient into a glove-shaped dressing. The glove-shaped dressing includes a wound contact layer, a barrier film layer, and a plurality of felted foam strips positioned between the barrier film layer and the wound contact layer. The method also includes sealing the glove-shaped dressing around a wrist of the patient, coupling the glove-shaped dressing to a pump such that the pump is in fluid communication with the plurality of felted foam strips, and operating the pump to remove air from the felted foam strips.

[0040] In some embodiments, the method includes forming creases in the barrier film layer by operating the pump to remove air from the glove-shaped dressing via the felted foam strips.

Operating the pump may cause fluid to flow through the creases.

[0041] In some embodiments, coupling the glove-shaped dressing to the pump comprises positioning a connection pad on the barrier film layer at a felted foam pad. The plurality of felted foam strips extend from the felted foam pad. The method may also include coupling a tube to the pump and the connection pad. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG. 1 is a perspective view of a negative pressure and instillation wound therapy (NPWTi) system, according to an exemplary embodiment.

[0043] FIG. 2 is a block diagram of the NPWTi system of FIG. 1, according to an exemplary embodiment.

[0044] FIG. 3 is a top view of dressing for treating a hand wound and for use with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0045] FIG. 4 is a first cross-section view of the dressing of FIG. 3, according to an exemplary embodiment.

[0046] FIG. 5 is a second cross-section view of the dressing of FIG. 3, according to an exemplary embodiment.

[0047] FIG. 6 is a third cross-section view of the dressing of FIG. 3, according to an exemplary embodiment.

[0048] FIG. 7 is an illustration of a wound-dressing interface for use with a glove-shaped dressing used with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0049] FIG. 8 is a cross-section view of the wound-dressing interface of FIG. 7, according to an exemplary embodiment.

[0050] FIG. 9 is a cross-section view of the glove-shape dressing for use with the wound-dressing interface of FIG. 7, according to an exemplary embodiment.

[0051] FIG. 10 is a flowchart of a process for providing a physiotherapy mode with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0052] FIG. 11 is a first perspective view of a dressing for treating a hand wound and for use with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0053] FIG. 12 is a second perspective view of the dressing of FIG. 11, according to an exemplary embodiment.

[0054] FIG. 13 is a third perspective view of the dressing of FIG. 11, according to an exemplary embodiment.

[0055] FIG. 14 is a fourth perspective view of the dressing of FIG. 11, according to an exemplary embodiment.

[0056] FIG. 15 is a cross-sectional view of the dressing of FIG. 11, according to an exemplary embodiment.

[0057] FIG. 16 is an illustration of a process of operating the NPWTi system of FIGS. 1-2 with the dressing of FIG. 11, according to an exemplary embodiment.

[0058] FIG. 17 is a top view of another embodiment of a dressing for treating a hand wound and for use with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0059] FIG. 18 is a cross-sectional view of the dressing of FIG. 11, according to an exemplary embodiment. [0060] FIG. 19 is a pair of cross-sectional views of the dressing of FIG. 11 illustrating a knuckle flexion point, according to an exemplary embodiment.

[0061] FIG. 20 is a top view of another embodiment of a dressing for treating a hand wound and for use with the NPWTi system of FIGS. 1-2, according to an exemplary embodiment.

[0062] FIG. 21 is a perspective view of a collapsible cuff of an extremity dressing, according to an exemplary embodiment.

[0063] FIG. 22 is a cross-sectional side view of the collapsible cuff of FIG. 21, according to an exemplary embodiment.

[0064] FIG. 23 is a cross-sectional end view of the collapsible cuff of FIG. 21, according to an exemplary embodiment.

[0065] FIG. 24 is an illustration of operation of the collapsible cuff of FIG. 21, according to an exemplary embodiment.

[0066] FIG. 25 is an illustration of a collapsible manifold structure included with some embodiments of the collapsible cuff of FIG. 21, according to an exemplary embodiment.

[0067] FIG. 26 is a first view of a dressing with a collapsible cuff for treating a hand wound, according to an exemplary embodiment.

[0068] FIG. 27 is a second view of the dressing of FIG. 26, according to an exemplary embodiment.

DETAILED DESCRIPTION

Negative Pressure and Instillation Wound Therapy System

[0069] Referring to FIGS. 1 and 2, a negative pressure and instillation wound therapy (NPWTi) system 100 is shown, according to exemplary embodiments. FIG. 1 shows a perspective view of the NPWTi system 100, according to an exemplary embodiment. FIG. 2 shows a block diagram of the NPWTi system 100, according to an exemplary embodiment. The NPWTi system 100 is shown to include a therapy unit 102 fluidly coupled to a dressing 104 via a vacuum tube 106 and an instillation tube 108. In the embodiments described herein, the dressing 104 is configured for use in treating one or more wounds on a patient’s hand. The NPWTi system 100 is also shown to include an instillation fluid source 110 fluidly coupled to the instillation tube 108. The NPWTi system 100 is configured to provide negative pressure wound therapy at a wound bed by reducing the pressure at the dressing 104 relative to atmospheric pressure. The NPWTi system 100 is also configured to provide instillation therapy by providing instillation fluid to the dressing 104. By providing both negative pressure wound therapy and instillation therapy, the NPWTi system 100 is configured to facilitate wound healing. As described in detail below, the NPWTi system 100 is also configured to provide a physiotherapy mode that facilitates mobility, articulation, etc. of a patient’s hand during treatment by the NPWTi system 100. The NPWTi system 100 thereby facilitates wound healing while also allowing for functional rehabilitation of the hand and reducing the risk of contractures. [0070] Although the examples described herein show a NPWTi system 100 configured to provide both negative pressure wound therapy and instillation therapy, in other embodiments the system 100 is configured to provide negative pressure wound therapy (NPWT) without instillation therapy.

[0071] The dressing 104 is coupleable to a wound bed, i.e., a location of a wound (e.g., sore, laceration, bum, etc.) on a patient. In the examples herein, the dressing 104 is configured to be placed on a hand of a patient to cover a wound bed located on the hand. The dressing 104 may be substantially sealed over/around the wound bed such that a pressure differential may be maintained between the atmosphere and the wound bed (i.e., across the dressing 104). The dressing 104 may be coupled to the vacuum tube 106 and the instillation tube 108, for example to place the vacuum tube 106 and/or the instillation tube 108 in fluid communication with the wound bed. Embodiments of the dressing 104 are shown in FIGS. 3-9 and described in detail with reference thereto.

[0072] The dressing 104 includes one or more sensors 204. The one or more sensor(s) 204 are configured to measure one or more physical parameters at the dressing and provide the measurements to the control circuit 202, for example by transmitting the measurements via wireless communications (e.g., via a wireless network such as Bluetooth, WiFi, etc.). In the embodiments shown herein, the one or more sensor(s) 104 include a humidity sensor configured to measure humidity at the dressing 104, a moisture sensor configured to measure moisture at the dressing 104, and a strain sensor configured to measure a strain on the dressing 104. In some embodiments, the one or more sensor(s) 204 include one or more pH sensors to measure tissue pH or fluid pH.

[0073] The therapy unit 102 includes a negative pressure pump 112 (shown in FIG. 2 and obscured within the therapy unit 102 in the perspective view of FIG. 1) configured to pump air, wound exudate, and/or other debris (e.g., necrotic tissue) and/or fluids (e.g., instillation fluid) out of the dressing 104 via the vacuum tube 106, thereby creating a negative pressure at the dressing 104. The negative pressure pump 112 is fluidly communicable with the vacuum tube 106 and the dressing 104. Wound exudate and/or other debris and/or fluids removed from the wound bed by the negative pressure pump 112 may be collected in a canister 114 located on the therapy unit 102. The canister 114 may be removable from the therapy unit 102 to allow canister 114 to be emptied or replaced when the canister 114 fills with fluid and debris.

[0074] Operating the negative pressure pump 112 may therefore both create a negative pressure at the wound bed and remove undesirable fluid and debris from the wound bed. In some cases, operating the negative pressure pump 112 may cause deformation of the wound bed and/or provide other energy to the wound bed to facilitate debridement and healing of the wound bed. In various embodiments, the negative pressure pump 112 may be operated to provide various levels (amounts, values, etc.) of negative pressure at the wound bed (e.g., 30 mmHg, 60 mmHg, 75 mmHg, 125 mmHg, 150 mmHg, etc.) for example varying over time as part of a dynamic pressure control approach. In the embodiments described below, the negative pressure pump 112 is configured to operate, as controlled by the control circuit 202, to provide a first level of negative pressure at the wound bed corresponding to a wound therapy mode (e.g., 125 mmHg) and a second level of negative pressure at the wound bed corresponding to a physiotherapy mode (e.g., 60 mmHg), where the second level is closer to ambient air pressure than the first level.

[0075] The therapy unit 102 also includes an instillation pump 116. The instillation pump 116 is configured to selectively provide instillation fluid from the instillation fluid source 110 to the dressing 104. The instillation pump 116 is operable to control the timing and amount (volume) of instillation fluid provided to the dressing 104. The instillation pump 116 may be controlled in coordination with the negative pressure pump 112 to provide one or more wound treatment cycles that may facilitate wound healing. In some embodiments, the amount of fluid provided by the instillation pump is automatically determined using a wound volume estimation process executed by the therapy unit 102. [0076] The therapy unit 102 is also shown to include an input/output device 118. The input/output device 118 is configured to provide information relating to the operation of the NPWTi system 100 to a user and to receive user input from the user. The input/output device 118 may display status information relating to the NPWTi system 100, for example including measurements obtained from the sensor(s) 204 of the dressing 104 or the sensor(s) 200 of the therapy unit 102. The input/output device 118 may allow a user to input various preferences, settings, commands, etc. that may be used in controlling the negative pressure pump 112 and the instillation pump 116 as described in detail below. The input/output device 118 may include a display (e.g., a touchscreen), one or more buttons, one or more speakers, and/or various other devices configured to provide information to a user and/or receive input from a user.

[0077] As shown in FIG. 2, the therapy unit 102 is also shown to include one or more sensors 200 and a control circuit 202. The sensor(s) 200 may be configured to monitor one or more of various physical parameters relating to the operation of the NPWTi system 100. For example, the sensor(s) 200 may measure pressure at the vacuum tube 106, which may be substantially equivalent and/or otherwise indicative of the pressure at the dressing 104. As another example, the sensor(s) 200 may measure an amount (e.g., volume) of instillation fluid provided to the dressing 104 by the instillation pump 116. The sensor(s) 200 may provide such measurements to the control circuit 202.

[0078] The control circuit 202 is configured to control the operation of the therapy unit 102, including by controlling the negative pressure pump 112, the instillation pump 116, and the input/output device 118. The control circuit 202 may receive measurements from the sensor(s) 200 and the sensor(s) 204 and/or user input from the input/output device 118 and use the measurements and/or the user input to generate control signals for the instillation pump 116 and/or the negative pressure pump 112. For example, the control circuit 202 may control the negative pressure pump 112 and the instillation pump 116 to provide various combinations of various instillation phases, soak periods, and negative pressure phases (i.e., various pressures and instillation amounts over various durations) to support and encourage wound healing. As another example, as described in detail below with reference to FIG. 10, the control circuit 202 is configured to automatically initiate a wound therapy mode in response to strain measurements from the sensor(s) 204 by controlling the negative pressure pump 112 to reduce the negative pressure at the dressing 104, thereby allowing increased mobility, flexion, articulation, etc. of the hand treated by the dressing 104.

Hand Dressing for NPWTi or NPWT

[0079] Referring now to FIGS. 3-5, various views of a first embodiment of the dressing 104 is shown. FIG. 3 shows a top view of the dressing 104 and FIGS. 4-6 show various cross-sectional views of the dressing 104.

[0080] In FIGS. 3-5, the dressing 104 is shown to include a first manifold layer 300, a second manifold layer 302, a first barrier layer 304 that is adjacent to (e.g., abuts) the first manifold layer 300, and a second barrier layer 306 abuts the second manifold layer 302. The first manifold layer 300 and the second manifold layer 302 are positioned between the first barrier layer 304 and the second barrier layer 306. In some embodiments, the first manifold layer 300 is coupled to the first barrier layer 304 by an adhesive and/or the second manifold layer 302 is coupled to the second barrier layer 306 by an adhesive.

[0081] The dressing 104 is also shown to includes a first fenestrated film layer 308 that abuts the first manifold layer 300 with and a second fenestrated film layer 310 that abuts the second manifold layer 302. The first manifold layer 300 is positioned between the first fenestrated film layer 308 and the first barrier layer 304, and the second manifold layer 302 is positioned between the second fenestrated film layer 310 and the second barrier layer 306. In some embodiments, the first fenestrated film layer 308 is coupled to the first manifold layer 300 by an adhesive and/or the second fenestrated film layer 310 is coupled to the second manifold layer 302 by an adhesive. In preferred embodiments. The first fenestrated film layer 308 is configured to be easily separated from the second fenestrated film layer 310. That is, the first fenestrated film layer 308 and the second fenestrated film layer 310 are configured to not adhere to one another.

[0082] As illustrated in FIG. 5, the first manifold layer 300, the second manifold layer 302, the first barrier layer 304, the second barrier layer 306, the first fenestrated film layer 308, and the second fenestrated film layer 310 are hand-shaped. That is, each of the layers 302-310 includes a central region 312 and five peninsular projections 314 that extend from the central region 312 in the shape of a hand. Each of the five peninsular projections 314 corresponds to one finger or thumb of a patient. The dressing 104 may be made available in various sizes corresponding to different hand sizes (i.e., different dimensions of the central region 312 and the peninsular projections 314 of the layers 300- 310). For example, the dressing 104 may be available in a small size, a medium size, a large size, etc. to allow fitting to various patients without requiring individual/patient-specific customization.

[0083] The first barrier layer 304 is coupled to the second barrier layer 306 along a hand portion of a perimeter of the dressing 104 and separated from the second barrier layer 306 along a wrist portion 320 of the perimeter of the dressing 104. The first barrier layer 304 is not coupled to the second barrier layer 306 along the wrist portion 320 of the perimeter of the dressing 104, which creates an opening that allows a patient’s hand to be inserted into the dressing 104. In other words, the dressing 104 is formed as a glove. The dressing 104 is thereby configured to receive a patient’s hand between the first fenestrated film layer 308 and the second fenestrated film layer 310.

[0084] In the example shown, the first barrier layer 304 is coupled to the second barrier layer 306 along edges of the peninsular regions 314 and the central region 312 by film welds 316, and along a portion of the perimeter of the central region by anchor welds 318. FIG. 4 shows a cross-section view of the dressing 104 including film welds 316. The film welds 316 couple the first barrier layer 304 to the second barrier layer 306 and substantially prevent air from passing between the first barrier layer 304 and the second barrier layer 306 at the film welds. For example, the first barrier layer 304 may be thermally bonded to the second barrier layer 306 at the film welds 316.

[0085] FIG. 5 shows a cross-section view of the dressing includes film welds 316 and anchor welds 318. The anchor welds 318 couple the first manifold layer, the second manifold layer 302, the first barrier layer 304, the second barrier layer 306, the first fenestrated film layer 308, and the second fenestrated film layer 310 together along portions of the perimeter of the dressing where the anchor welds 318 are present. In the example shown, the anchor welds 318 include structures (e.g., staples, pins, etc.) extending through the layers 300-310 to restrict (e.g., substantially prevent) movement of the layers 300-310 relative to one another at the anchor welds 318. In other examples, adhesive is used along the anchor welds 318 to restrict movement of the layers 300-310 relative to one another at the anchor welds 318.

[001486] The dressing 104 is also shown to include an adhesive cuff 322. Adhesive cuff 322 includes an adhesive (or multiple adhesives) configured to seal the adhesive cuff 322 to the first barrier layer 304 and the second barrier layer 306 along the wrist portion 320 of the perimeter of the dressing and to skin of a patient. The adhesive cuff 322 extends from the first barrier layer 304 and the second barrier layer 306 such that the adhesive cuff 322 is configured to be coupled to a wrist of a patient when the patient’s hand is inserted into the dressing 104. When the adhesive cuff 322 is sealed to a patient’s wrist, the first barrier layer 304, and the second barrier layer 306, the adhesive cuff 322 substantially prevents air from flowing between an ambient environment and the interior of dressing 104 (e.g., the manifold layers 300, 302) via the opening at the wrist portion 320 of the dressing 104. The adhesive cuff 322 may be produced as an integrated piece of the dressing 104 or may be distributed as a separate piece of a dressing kit (e.g., as an adhesive strip).

[0087] The barrier layers 304, 306 are configured to substantially prevent airflow therethrough. The barrier layers 304, 306 may include a polyurethane drape material, for example a drape material as used in a V.A.C.® Drape by Acelity. As mentioned above, the barrier layers 304, 306 are sealed with a substantially-airtight seal by film welds 316. Accordingly, when the adhesive cuff 322 is sealed around the wrist of a patient and the barrier layers 304, 306, a substantially airtight volume is created within the dressing 104, i.e., between the barrier layers 304, 306 and the patient’s hand. The barrier layers 304, 306 may each have a thickness in a range between approximately 80 and 120 microns. [0088] As shown in FIGS. 3, the first barrier layer 304 includes knuckle flexion points 324 arranged at positions that correspond to knuckles/joints within a typical hand that may be inserted into the dressing 104. In the example shown, each peninsular portion 314 corresponding to a finger includes three knuckle flexion points 324, while the peninsular portion 314 corresponding to a thumb includes two knuckle flexion points. FIG. 6 shows cross sectional views of a knuckle flexion point 324, includes a first view 600 of the knuckle flexion point 324 in an unflexed state and a second view 602 of the knuckle flexion point 324. As illustrated by FIG. 6, each knuckle flexion point 324 includes a series of folds (e.g., three folds) which, in the unflexed state, draw the barrier layer 304 away from the manifold layer 300. In the flexed state, the series of folds are extended (unfolded) to facilitate curvature (bending) of the dressing 104 at the knuckle flexion point 324 by increasing an effective length of the barrier layer 304. Accordingly, the knuckle flexion points 324 are configured to facilitate articulation, movement, etc. of a patient’s fingers confined in the dressing 104. The fenestrated film layers 308, 310 and the manifolding film layers 300, 302 may be configured to resiliently stretch and/or flex to accommodate articulation, movement, etc. of a hand in the dressing 104 as shown in FIG. 6.

[0089] The fenestrated film layers 308, 310 are made of a non-adherent film and are configured to provide a non-adherent interface between the dressing 104 and a hand of a patient, including a wound bed located on the hand. The fenestrated film layers 308, 310 are also configured to prevent ingrowth of skin to the dressing (e.g., healing into the manifold layers 300, 302). The fenestrated film layer 308, 310 thereby facilitate easy insertion of a hand into the dressing 104 and removal of the hand from the dressing 104. Additionally, the fenestrated film layers 308, 310 have fenestrations (perforations, holes, airways, windows, etc.) extending therethrough that allow air and fluid to pass between the hand (e.g., a wound bed) and the manifold layers 300, 302. The fenestrated film layers 308 may each have a thickness of approximately 30 microns.

[0090] The manifold layers 300, 302 are configured to allow air and fluid to flow therethrough. The manifold layers are made of an open-cell foam, for example a reticulated polyurethane open cell foam. In some embodiments, the manifold layers 300, 302 are made of an open-cell foam marketed as GRANUFOAM™ by ACELITY™ The manifold layers 300, 302 may each have a thickness in a range between approximately 6mm and 10mm. Accordingly, the manifold layers 300, 302 may be thinner than in conventional bulky dressings. The reduced thickness of the manifold layers 300, 302 facilitates flexion of the dressing 104 to allow for physiotherapy for the hand in the dressing 104 in a way not previously achieved.

[0091] The manifold layers 300, 302 allow for the communication of air pressure, for example negative pressure (relative to ambient air pressure), through the manifold layers 300, 302 and to the hand and the wound bed (via the fenestrated film layers 308, 310. The dressing 104 is configured such that air and fluid can flow between the first manifold layer 300 and the second manifold layer 302 proximate the film welds 316 and anchor welds 318, i.e., through the fenestrated film layers 308, 310 and around a hand positioned in the dressing 104. Negative pressure can thereby be communicated across both manifold layers 300, 302 (i.e., such that both manifold layers 300, 302 are maintained at approximately equal pressures).

[0092] The dressing 104 is configured to be coupled to a vacuum (negative pressure) tube 106 and, in some embodiments, an instillation tube 108. For example, a hole may be cut in the first barrier layer 304 (e.g., with a diameter in a range between approximately 3-20mm) and a connection pad may be coupled to the barrier layer 304 over the hole. The connection pad is coupled to the vacuum tube 106 and/or instillation tube 108. In some embodiments, multiple holes and/or connection pads are used. For example, the connection pad may be a SENSAT.R.A.C.™ connection pad marketed by ACELITY™

[0093] The manifold layers 300, 302 can thereby be put in fluid communication with the vacuum tube 106 and/or instillation tube 108. As described above with reference to FIGS. 1-2, the negative pressure pump 112 can be controlled to remove air from the manifold layers 300, 302 to establish a negative pressure at the manifold layers 300, 302. The negative pressure at the manifold layers 300, 302 is communicated to the hand/wound via the fenestrations in the fenestrated film layers 308, 310. Instillation fluid may also be provided to the wound via the manifold layers 300, 302 and the fenestrated film layers 308. Wound exudate, instillation fluid, other debris, etc. may also be removed from the wound and manifold layers via the vacuum tube 106 as described above with reference to FIGS. 1-2. The dressing 104 thereby facilitates treatment of a hand wound using NPWTi.

[0094] Still referring to FIGS. 3-6, the dressing 104 is also shown to include one or more sensor(s) 204. positioned on the first barrier layer 304. In the embodiment shown, the one or more sensor(s) include a humidity sensor and a moisture sensor, which may be positioned extending through the first barrier layer 304 to measure humidity and moisture in the first manifold layer 300. In some embodiments, the one or more sensor(s) include one or more pH sensor(s) configured to measure tissue pH and/or fluid pH. In the embodiment shown, the one or more sensor(s) also include a strain sensor 326. The strain sensor 326 is positioned on or in the first barrier layer 304 and extends along a length of the dressing from proximate the wrist portion 320 to a tip of one of the peninsular regions 314 (e.g., corresponding to a middle finger). The strain sensor 326 is configured to measure (e.g., generate an electrical signal indicative of) a strain on the dressing 104 (i.e., on the strain sensor 326), which may correspond to a curvature of the dressing 104 and/or a force applied by the hand inside the dressing 104. For example, a strain measured by the strain sensor 326 may increase when a patient attempts to clench the hand (e.g., in a fist) or otherwise bend one or more fingers in the dressing 104. The strain may decrease when the patient moves the hand in the dressing 104 to an open or neutral pose. The one or more sensors 204 include a wireless communications circuit (e.g., WiFi transceiver, Bluetooth transceiver, etc.) configured to facilitate wireless transmission of measurements from the one or more sensors to the control circuit 202 of the therapy unit 102. [0095] Referring now to FIGS. 7-9, a second embodiment of the dressing 104 is shown, according to an exemplary embodiment. In FIGS. 7-9, the non-adhesive fenestrated fdm layers 308, 310 are omitted from the dressing 104, such that the dressing 104 is formed as a glove including the barrier layers 304, 306 and the manifold layers 300, 302 arranged as described above. A wound-dressing interface 700 is also included as a separate piece (i.e., distributed to caregivers/patients as a separate piece in a dressing kit that also includes the glove-shaped dressing 104 formed from the barrier layers 304, 306 and the manifold layers 300, 302). The wound-dressing interface 700 is formed as a single piece (sheet) as shown in FIG. 4, for example shaped within peninsular extensions and or bridge/isthmus-shaped portions configured to be aligned with fingers of a patient when the wound dressing interface 700 is folded over a patient’s hand.

[0096] The wound-dressing interface 700 includes a patient interface layer 702 and a foam interface layer 704. The foam interface layer 704 includes a fenestrated film, for example a polyurethane or polyethylene film with fenestrations extending therethrough. The foam interface layer 704 allows air and fluid to flow therethrough and limits adherence of the wound-dressing interface 700 to the manifold layers 300, 302. The patient interface layer 702 includes a perforated silicone and a hydrogel or polyurethane gel. The patient interface layer 702 is configured to adhere to itself. In some embodiments, the patient interface layer 702 is configured to adhere to skin.

[0097] The wound-dressing interface 700 is thereby configured to be folded over a hand and adhered to itself (mated to itself) to substantially enclose the hand in the wound dressing interface 700 such that the patient interface layer 702 faces inwards (i.e., towards the hand) and the foam interface layer 704 faces outwards (i.e., away from the hand). The hand and the wound-dressing interface 700 can then be inserted into the glove portion of the dressing 104, i.e., the barrier layers 304, 306 and the manifold layers 300, 302 arranged as described above (and as shown in FIGS. 9 and 3). With the hand enclosed in the wound-dressing interface 700, the wound-dressing interface 700 prevents direct contact between the hand and the manifold layers 300, 302 while allowing air and fluid to pass through fenestrations in the wound-dressing interface 700. The adhesive cuff 322 can then be applied around the patient’s wrist to seal the dressing 104 around the hand as described above. To further prepare the dressing 104 for NPWTi, a hole can be cut in a barrier layer 304, 306 and a connection pad coupled to the barrier layer 304, 306 over the hole to place a vacuum tube 106 and/or an instillation tube 108 in fluid communication with the manifold layers 300, 302. The therapy unit 102 can then be operated as described above to establish negative pressure at the hand and/or provide instillation fluid to the hand.

[0015] The embodiments of FIGS. 3-9 show glove-shaped dressings, i.e., with individually- differentiated fingers (e.g., as formed by peninsular projections 314). Other embodiments of the dressing 104 may be mitten-shaped, i.e., with a unified area for four fingers and a separate projection for a thumb. Such mitten-shaped dressings may otherwise be configured as described herein for the glove-shaped dressings of FIGS. 3-9. Other variations are also contemplated by the presented disclosure, for example a three -compartment glove where the two pairs of fingers each share a compartment and the thumb has a compartment, etc. All such variations are within the scope of the present disclosure.

[0016] Referring now to FIG. 10, a process 1000 of providing a physiotherapy mode with the NPWTi system 100 of FIG. 1-2 and the hand dressing 104 of FIGS. 3-9 is shown, according to an exemplary embodiment. Process 1000 provides a physiotherapy mode that allows movement, articulation, bending, etc. of a hand in the dressing 104 during NPWTi treatment. Accordingly, execution of process 1000 facilitates a patient in redeveloping strength, neuromuscular activity, coordination, etc. in the hand while the dressing 104 is applied to the hand. Additionally, movement of the hand as provided for by process 1000 reduces the risk of contracture, i.e., the risk that the skin may heal too tight such that the patient’s skin restricts the range of motion of the joints in the hand. Movement, articulation, etc. of the fingers and hand during wound healing may facilitate proper healing that allows for a full range of motion of the hand after wound healing. Process 1000 can be executed by the control circuit 202 of the therapy unit 102.

[0100] At step 1002, the negative pressure pump 112 is operated to establish a first level of negative pressure at the glove-shaped dressing 104. The first level of negative pressure may correspond to a preferred level for negative pressure wound therapy, for example in the range of approximately 100 mmHg to 175 mmHg of negative pressure. When the first level of negative pressure is applied, the pressure differential between the ambient air and the interior of the dressing 104 increases the rigidity of the dressing 104 such that dressing 104 substantially restricts (limits, prevents, etc.) articulation of the hand.

[0017] At step 1004, a measurement is received from the strain sensor 326 on the glove-shaped dressing 104. The measurement includes a current value of a strain on the dressing 104. The strain on the dressing 104 may correspond to an amount of force exerted on the dressing 104 by the hand in the dressing 104 in an attempt to curl, bend, articulate, etc. the fingers in the dressing 104. The measurement may be received by the control circuit 202 via a wireless network (e.g., Bluetooth communications, WiFi communications, etc.).

[0018] At step 1006, the measurement is compared to a threshold strain value. The threshold strain value may be predetermined, for example by bench testing. The threshold strain value corresponds to a significant probability that the patient is deliberately attempting to articulate the hand in the dressing 104. In the measurement does not exceed the threshold measurement, pump 112 continues to be controlled to provide the first level of negative pressure at the dressing 104 while more measurements of the strain are received at the control circuit 202 over time.

[0019] If a determination is made that the measurement of the strain exceeds the threshold strain value, a physiotherapy mode is initiated at step 1008. At step 1008, the pump 112 is controlled (e.g., by the control circuit 202) to reduce the negative pressure from the first level of negative pressure to a second level of negative pressure. The second level of negative pressure is “lower” than the first level of negative pressure, i.e., closer to atmospheric pressure (e.g., in a range of approximately 25mmHg to 75 mmHg). At the second level of negative pressure, the rigidity of the dressing 104 is lower than at the first level of negative pressure. Accordingly, at the second level of negative pressure, the dressing 104 and the NPWIT system 100 allows the patient to at least partially bend, articulate, move, etc. the fingers and hand in the dressing 104. For example, the patient may follow guided instructions from a therapist. In some embodiments, the therapy unit is configured to provide instructions for a physiotherapy routine to a user via the input/output device 118.

[0020] At step 1010, additional measurements of the strain are received from the strain sensor 234. As the patient continues to articulate the hand in the dressing 104, the strain will stay above the threshold strain value and/or repeatedly exceed the threshold strain value. At step 1012, a determination is made of whether the measurement has fallen below the threshold strain value for at least a threshold duration of time. The threshold duration of time may be selected as indicative that the patient has ended a physiotherapy routine or other attempt to articulate the hand in the dressing 104. If the strain has not fallen below the threshold strain value for at least the threshold duration of time, the pump 112 continues to be controlled to maintain the second level of negative pressure at the dressing.

[0021] If the strain has fallen below the threshold strain value for at least the threshold duration of time, the pump 112 is controlled to reestablish the first level of negative pressure at the dressing at step 1014, i.e., to reestablish an optimal NPWTi regime and exit the physiotherapy mode. The process may then return to step 1004 where the strain measurements are monitored. Repeated iterations of the physiotherapy mode may thereby be initiated and exited to facilitate both physiotherapy and NPWTi for the hand in the dressing 104 overtime. With the advantages described above, the dressing 104 may be well-suited for long-term application to the hand (e.g., seven days or longer).

[0022] Several variations on the process 1000 are also contemplated by the present disclosure. For example, in some embodiments, the physiotherapy mode can be initiated or ended in response to user input to the input/output device 118 commanding a start or end to the physiotherapy mode. As another example, the control circuit 202 may prevent execution of the process 1000 (e.g., prevent initiation of physiotherapy mode) during an instillation cycle (e.g., while instillation fluid is being supplied to the dressing 104). As another example, in some embodiments, a dynamic pressure control mode (e.g., cyclic variations in negative pressure) is applied outside of the physiotherapy mode (e.g., in place of the first level of negative pressure). Various such variations are possible.

[0023] Additionally, although the embodiments described herein are designed for use on hands, variations suitable for use on feet or amputation stumps are also within the scope of the present disclosure. For example, a variation suitable for use on a foot may be formed as a sock, with or without a separate pocket/projection for each toe, rather than as a glove as shown for the hand dressings described above. Variations of the dressing 104 can therefore be tailored for use in treating wounds in many anatomical locations. [0024] The dressing 104 and NPWTi system 100 described above provide various advantages over existing dressings and wound therapy systems. The dressing 104 is easy to apply (thereby reducing application time) and remove without damaging the healed/healing wound (e.g., by avoiding a risk of in-growth into the dressing structure). The dressing 104 and NPWTi system 100 also allow for effective positioning of the dressing 104 while also allowing early movement in the full range of motion (or at least a significant portion of the range of motion) of the wounded/treated hand. The dressing 104 and NPWTi system 100, in the embodiments shown, are suitable for providing negative pressure and instillation therapy for up to at least seven days. The dressing 104 may reduce the use of foam relative to existing dressings, thereby making the dressing 104 smaller and less cumbersome for the patient. The dressing 104 and the NPWTi system 100, in the embodiments shown, also provide for an automatic physiotherapy mode that facilitates rehabilitation and reduces the risk of contractures. Additionally, the dressing 104 includes sensors that wirelessly (e.g., without the annoyance/complication of additional cables/wires/etc.) communicate useful measurements/diagnostics to a caregiver that allow early detection of infection or other developments in wound treatment. Therefore, the dressing 104 and NPWTi system 100 disclosed herein provide many advantages over existing systems that can improve outcomes for patients while also improving the overall treatment experience.

[0025] Referring now to FIGS. 11-16, another embodiment of the dressing 104 is shown, according to exemplary embodiments. FIGS. 11-14 show various perspective views of the dressing 104. FIG.

15 shows a cross-sectional view of the dressing 104. FIG. 16 illustrates an advantageous behavior of the dressing 104 when air is removed from the dressing 104. The dressing 104 as in FIGS. 11-16 may include some or all of the various features and advantages of the dressing 104 in the embodiments described above, with some differences as described in detail below. Advantageously, as shown in FIGS. 11-16, the dressing 104 includes transparent or translucent portions such that a patient or caregiver can visually assess a wound without removing the dressing 104 from the patient’s hand. [0026] As shown in FIGS. 11-16, the manifold layers 300, 302 are formed as multiple felted foam strips 1100 which extend from a felted foam pad 1102. Each felted foam strip extends from the central region 312 of the dressing to one of the multiple peninsular projections 314. In other words, each “finger” (including the “thumb”) of the dressing 104 has a corresponding felted foam strip 1100 aligned therewith. In the example shown, both a first side 1110 of the dressing 104 (corresponding to a back of the hand) and a first side 1112 of the dressing 104 (corresponding to the palm of the hand) include felted foam strips 1100. Accordingly, in this example, two felted foam strips 1100 are aligned with each of the peninsular projections 314 (i.e., one felted foam strip 100 on the first side 1110 and one felted foam strip 1100 on the first side 1112). It should be understood that various arrangements, numbers, patterns, webs, lattices, etc. of felted foam strips 1100 are possible in various embodiments. [0027] In the example of FIGS . 11 - 14, the felted foam pad 1102 includes a wrist strap 1104 and a connection surface 1106. The wrist strap 1104 (e.g., felted foam cuff) is located at a wrist region of the dressing 104 and connects the felted foam strips 1100 of the first side 1110 with the felted foam strips 1100 of the first side 1112, thereby allowing air and fluid to flow between the felted foam strips 1100 of the first side 1110 and the felted foam strips 1100 of the second side (e.g., to facilitate communication of negative pressure between the first side 1110 and the second side 1112).

[0028] The connection surface 1106 provides an area of felted foam having a sufficient surface area to allow connection of the dressing 104 to the tube 106 in fluid communication with the manifolding layer 300 (i.e., with the wrist strap 1104 and the felted foam strips 1100). In the example shown, the felted foam strips 1100 and the wrist strap 1104 may be narrow (e.g., having a width less than a diameter of a connection pad 1108 which couples the dressing 104 to the vacuum tube 106 and, in some embodiments, to the instillation tube 108. The connection surface 1106 provides a larger surface area (e.g., having a diameter equal to or larger than the diameter of the connection pad 1108; having a diameter in a range between approximately ten millimeters and approximate twenty-five millimeters, for example approximately twenty millimeters; etc.) which allows the tube 106 to be placed in fluid communication with the manifolding layer 300. In the example shown in FIG. 11, the connection surface 1106 of the felted foam pad 1102 is located along a forearm region of the dressing 104, such that the connection pad 1108 is positioned at a non-articulating anatomical feature when applied to a patient. The connection surface 1106 thereby provides a convenient, comfortable, and effective position at which the connection pad 1108 can be coupled to the dressing 104.

[0029] As shown in FIG. 15 and consistent with the embodiment of FIGS. 4-5 described above, the dressing 104 includes as a first manifold layer 300 (shown as a felted foam strip 1100), a second manifold layer 302 (also shown as a felted foam strip 1100), a first barrier film layer 304, a second barrier film layer 306, a first fenestrated film layer (wound contact layer) 308, and a second fenestrated film layer (wound contact layer) 308. The first manifold layer 300 is positioned between the first fenestrated film layer 308 and the first barrier layer 304, and the second manifold layer 302 is positioned between the second fenestrated film layer 310 and the second barrier layer 306. The first manifold layer 300, the first fenestrated film layer 308, and the first barrier film layer 304 form a first side 1110 of the dressing 104. The second manifold layer 302, the second fenestrated film layer 310, and the second barrier layer 306 form a second side of the dressing 104. In some embodiments, the first side 1110 and/or the first side 1112 are thermoformed to have a domed cross section to match the anatomical curvature of a hand, thereby improving fit, aesthetics, and comfort of the dressing 104. [0030] In the example of FIGS. 11-16, the first manifold layer 300 and second manifold layer 302 are formed as felted foam strips 1100 that occupy only a portion (i.e., less than an entirety) of the surface area of the barrier film layers 304, 306 and only a portion (i.e., less than an entirety) of the surface area of the fenestrated film layers 308, 310. The felted foam strips 1100 may have a width in a range of approximately two millimeters to ten millimeters, and may have a thickness in a range of approximately one millimeter to two millimeters. In regions of the dressing 104 unoccupied by the felted foam strips 1100, the first barrier film layer 304 is adjacent to (e.g., abutting) the first fenestrated film layer 308 and the second barrier film layer 306 is adjacent to the second fenestrated film layer 310.

[0031] In some embodiments, the barrier film layers 304, 306 and the fenestrated film layers 308 are transparent or translucent. In such embodiments and in regions unoccupied by the felted foam strips 1100, the dressing 104 can be transparent or translucent. Accordingly, in the embodiments of FIGS.

11-16, the dressing 104 is configured to allow a patient or caregiver to visually assess (see, optically inspect, etc.) a wound through the dressing 104 without removal or modification of the dressing 104. The dressing 104 thereby facilitates a caregiver or patient in monitoring wound healing and, in some cases, making adjustments to wound therapy based on such monitoring.

[0032] The first side 1110 and the first side 1112 may be coupled together by welds 316 and/or 318 around a perimeter of the dressing 104 with the exception of an opening at a wrist portion 320 of the perimeter of the dressing 104 (e.g., as described above with reference to FIGS. 3-5). In the examples of FIGS. 11-16, spot welds 1600 may also be included and distributed between and around the felted foam strips 1100. At the first side 1110, the first barrier film layer 304 is coupled (e.g., welded, adhered) to the first fenestrated film layer 308. At the first side 1112, the second barrier film layer 306 is coupled to the second fenestrated film layer 310. The spot welds 1600 may be placed to partially constrain movement of the of the felted foam strips 1100. For example, spot welds 1600 may be placed slightly apart from the felted foam strips 1100 such that the felted foam strips 1100 are allowed to move, bend, translate, slide, etc. within a limited range of positions relative to the barrier film layer 304/306 and the fenestrated film layer 308/310. In some cases, the spot welds 1600 ensure that the felted foam strips 1100 remain substantially aligned with the peninsular (finger, thumb) regions 314 while allowing for some movement and repositioning which facilitates the dressing 104 in conforming to a particular patient’s hand, provides flexibility to the dressing 104, and facilitates articulation of the patient’s hand while the dressing 104 is applied to the hand. In other embodiments, an adhesive can be included to couplet the felted foam strips 1100 to the barrier film layer 304/306 and/or the fenestrated film layer 308/310.

[0033] FIG. 16 illustrates application and use of the dressing 104 of FIGS. 11-15 in a two-frame storyboard depiction. As illustrated in the first frame 1601, the dressing 104 is placed onto a patient’s hand and the adhesive cuff 322 is applied to seal the dressing 104 around the patient’s wrist or forearm. In various embodiments, the dressing 104 may include a wrist/forearm region of various lengths (i.e., to extend along a forearm of a patient), such that the opening may align with various locations on the forearm of the patent in various embodiments. The dressing 104 may be sized slightly larger than the hand to facilitate insertion of the hand into the dressing 104. When the adhesive cuff 322 is sealed around the opening in the dressing 104 and the patient’s wrist or forearm, a substantially-airtight internal volume is created between the dressing 104 and the hand.

[0034] To transition from the first frame 1601 to the second frame 1602, the negative pressure pump 112 is operated to remove air and/or other fluids or debris from the dressing 104 via the tube 106, the connection pad 1108, the felted foam pad 1102, and the felted foam strips 1100 to establish a negative pressure within the dressing 104 and at the hand (e.g., at a wound). Operating the negative pressure pump 112 results in a reduction in volume of the dressing 104 as the dressing 104 is pulled inwards towards the hand by the pressure differential across the barrier fdm layers 304, 306.

[0035] As illustrated in the second frame 1602, the reduction in volume of the dressing 104 in response to operation of the negative pressure pump 112 results in the formation of wrinkles (creases, folds, etc.) in the barrier fdm layers 304, 306 and the fenestrated fdm layers 308, 310. The wrinkles may form with openings, gaps, channels, airways, etc. in and across the wrinkles, such that at least a portion of the wrinkles provide manifolding pathways for air and fluid flow. For example, gaps, channels, etc. may be formed between the barrier fdm layers 304, 306 and the fenestrated fdm layers 308, 310. Furthermore, at least a portion of the wrinkles are in fluid and/or pneumatic communication with the felted fdm strips 1100. Accordingly, air and fluid can flow between the felted fdm strips 1100 and regions of the hand not directly aligned with the felted foam strips 1100. [0036] Therefore, although the felted foam strips 1100 cover only a portion of the surface area of the dressing 104 and the hand treated thereby, the wrinkles formed by operation negative pressure pump 112 can provide air and fluid manifolding to a much larger portion of the surface area of the dressing 104 and the hand (e.g., to the substantially the entire hand). The dressing 104 thereby facilitates the establishment and maintenance of a negative pressure at the hand, removal of wound exudate and other fluid/debris from the hand, and, in some embodiments, instillation of an instillation fluid to the hand. Furthermore, as the (substantially opaque) felted foam material covers only a portion of the surface area of the dressing 104, a patient or caregiver can visually inspect a wound without removing the dressing 104, including while negative pressure is established at the hand.

[0037] In some embodiments, one or more thermo-chromic indicators are positioned on the fenestrated film layers 308, 310, for example on the inner (i.e., hand-facing) surface or outer (i.e., non-hand-facing) surface of the fenestrated film layers 308, 310. The thermo-chromic indicators are configured to change color with changes in temperature, such that the color of a thermo-chromic indictor is indicative of the temperature of the skin or wound bed proximate the thermo-chromic indicator. Because the dressing 104 of FIGS. 11-16 is translucent or transparent in various regions, such indicators may be visible through the dressing 104, thereby allowing a patient or caregiver to assess wound healing on the basis of temperature indications. Such temperature indicators may be particularly useful in assessment and treatment of bums. Multiple indicators can be used to provide temperature information at multiple locations of the dressing 104. In some embodiments, pH-chromic indicators configured to change color with changes in pH may be included with the dressing 104 and opinionated like the thermo-chromic indicators to provide information relating to the pH of the hand at various areas of the hand.

[0038] Various other embodiments of the dressing 104 are also possible. For example, in some embodiments the felted foam strips 1100 are non-felted. That is, the foam strips 1100 may be made of an open-celled polyurethane foam which may or may not be felted (e.g., heated and compressed) in various embodiments. In other embodiments, the felted foam strips 1100 are replaced by non-foam thermoformed pathways, for example tubes or other pathways formed on or coupled to the barrier fdm layer (e.g., formed of a polyurethane drape material). In other embodiments, various spacer materials are positioned to cause the wrinkles to form in a desired pattern, in some cases such that some or all of the felted foam strips 1100 can be omitted.

[0039] Although the embodiments herein are described with reference to a dressing shaped for a hand, the dressings, systems, and methods disclosed herein may be adapted for use with feet, amputation stumps, and other extremities. Furthermore, various combinations of the features and embodiments described herein are possible. For example, in some embodiments, the first side 1110 of the dressing 104 includes the felted foam strips as in FIGS. 11-16, while the second side 1112 includes a sold/continuous manifold layer 302 as in FIGS. 3-5 (or vice versa). Various combinations of felted foam materials, strips, pads, zones, etc. may be used to customize wound therapy. All such variations are within the scope of the present disclosure.

Transparent Hand Dressing for NPWTi or NPWT

[0040] Referring now to FIGS. 17-18, a dressing 1700 is shown, according to an exemplary embodiment. FIG. 17 shows atop view of the dressing 1700, while FIG. 18 shows a cross-sectional end view of the dressing 1700. The dressing 1700 may be used with the NPWTi system 100 described above, and may facilitate the communication of negative pressure to a wound treated using the dressing 1700. As described in detail below, the dressing 1700 also allows fluid to flow from such a wound to a therapy unit 102 as described above with reference to FIG. 1. Furthermore, the dressing 1700 may be transparent to allow a caregiver to visually assess the wound without removing the dressing 1700.

[0041] As shown in FIGS. 17-18, the dressing 1700 includes first side 1708 that includes a first barrier layer or film 1702, a first thermoformed layer 1704 (e.g., manifold layer or film), and a first wound contact layer or film (patient interface layer) 1706. The first thermoformed layer 1704 is positioned between the first wound contact layer 1706 and the first barrier film 1702. As shown in FIG. 18, the dressing 1700 also includes a second side 1710 coupled to the first side 1708. The second side includes a second barrier layer or film 1712, a second thermoformed layer 1714 (e.g., manifold layer or film), and a second wound contact layer or film 1716. The first side 1708 and the second side 1710 are coupled together such that the first wound contact layer 1706 is adjacent the second wound contact layer 1716, with an opening therebetween as shown in FIG. 18. Accordingly, the first thermoformed layer 1704 is separated from the second thermoformed layer 1714 by the first wound contact layer 1706 and the second wound contact layer 1716, while the first barrier film 1702 is separated from the second barrier film 1712 by the first thermoformed layer 1704, the second thermoformed layer 1714, the first wound contact layer 1706, and the second wound contact layer 1716. [0042] In the example of FIG. 17, the dressing 1700 is shaped as a glove and is configured to be applied to a hand of a patient. As shown, the dressing 1700 (e.g., the first side 1708 and the second side 1710 and the layers thereof) include a palm region (e.g., central section) 1720 and a plurality of digit regions (e.g., peninsular projections) 1722. For example, five digit regions 1722 are included in the example of FIG. 17. The first side 1708 is welded to the second side 1710 along the perimeter of the digit regions 1722 and the palm region 1720 except at an opening at a cuff (wrist region) 1724 of the dressing 1700. The dressing 1700 is thereby configured to receive a patient’s hand between the first wound contact layer 1706 and the second wound contact layer 1716, for example by film parameter welds 1800 as shown in FIG. 18. The dressing 1700 includes knuckle flexion points 1740 (shown in detail in FIG. 19 and described with reference thereto below) positioned at the digit regions 1722 to facilitate bending of the digit regions 1722. In alternative embodiments, the dressing 1700 is configured to receive a foot or other extremity (e.g., arm, leg, amputation stump, etc.) of a patient. [0043] The first barrier film 1702 and the second barrier film 1712 may be a substantially air- impermeable film. The first barrier film 1702 and the second barrier film 1712 are configured to define a substantially-airtight volume between the dressing 1700 and the extremity received by the dressing 1700 when the dressing is sealed over the extremity.

[0044] The first barrier film 1702 and the second barrier film 1712 may be made of a polyurethane film having a thickness in a range between approximately 80 microns and approximately 120 microns. The first barrier film 1702 and the second barrier film 1712 may be configured in the same or similar manner as the first barrier layer 304 and second barrier layer 306 described above. In some embodiments, the first barrier film 1702 and the second barrier film 1712 are transparent, i.e., configured to transmit a sufficient amount of visible light therethrough to allow visual inspection of a wound seen by a caregiver through the first barrier film 1702 or the second barrier film 1712.

[0045] The first wound contact layer 1706 and the second wound contact layer 1716 are configured to contact a wound and other tissue of a patient while preventing ingrowth of tissue to the dressing 1700, allowing a negative pressure to be communicated to the wound, and allowing wound exudate to be drawn away from the wound. The first wound contact layer 1706 and the second wound contact layer 1716 are transparent (e.g., sufficiently transparent to permit inspection of a wound without dressing removal). The first wound contact layer 1706 and the second wound contact layer 1716 may be made of a fenestrated polyurethane film, for example with a thickness in a range between approximately twenty (20) microns and approximately eighty (80) microns, for example approximately thirty (30) microns. The polyurethane film may be adhesive-coated, for example as marketed as Inspire 2237 by Transcontinental Inc., or non-adhesive-coated, for example as marketed as Inspire 2034 by Transcontinental Inc. The first wound contact layer 1706 and the second wound contact layer 1716 may be configured same as or substantially similar to the first fenestrated film layer 308 and the second fenestrated film layer 310 described above. The first wound contact layer 1706 may be coupled to the first thermoformed layer 1704 by spot welds, adhesive coating, and/or parameter welds. The second wound contact layer 1716 may be coupled to the second thermoformed layer 1714 by spot welds, adhesive coating, and/or parameter welds. The first wound contact layer 1706 and the second would contact layer 1716 may be configured such that the dressing 1700 can be classified as a 7-day-wear dressing.

[0046] The first thermoformed layer 1704 and the second thermoformed layer 1714 are configured to provide open volumes and pathways within the first side 1702 and second side 1710. Each thermoformed layer 1704, 1714 includes a substantially flat film with three-dimensional structures formed (e.g., thermoformed, embossed) on a surface thereof and extending from the surface. The structures may be shaped as pillars, bumps, walls, ridges, etc., and may be arranged in various patterns in various embodiments. In the example shown in FIG. 17, the structures are formed as round bumps (e.g., hemispheres) or pillars (e.g., cylinders) spaced approximately evenly and distributed across each thermoformed layer 1704, 1714. Each bump or pillar may have a diameter in a range between approximately two (2) millimeters and approximately four (4) millimeters, and a height in a range between approximately two (2) millimeters and approximately five (5) millimeters. In other embodiments, the structures may have a shape that is oval, triangular, square, pentagonal, hexagonal, etc.

[0047] In some embodiments, the thermoformed layers 1704, 1714 (including the structures) are transparent (e.g., sufficiently transparent to allow inspection of a wound without dressing removal). The thermoformed layers 1704, 1714 may also be flexible. The structures and the film may be made of a polyurethane, with the structures embossed or otherwise thermoformed on a surface of the thermoformed polyurethane. For example, the thermoformed layers 1704, 1714 may be have a thickness between approximately 200 microns and approximately 500 microns. The thermoformed layers 1704, 1714 include fenestrations that allow air and fluid to move through the thermoformed layers 1704, 1714 via the fenestrations. The fenestrations in the first thermoformed layer 1704 may be aligned with the perforations in the first wound contact layer 1706, and the fenestrations in the second thermoformed layer 1714 may be aligned with the perforations in the second wound contact layer 1716, thereby allowing fluid and air to pass through the perforations and fenestrations to cross the thermoformed layers 1704, 1714 and the wound contact layers 1706, 1716.

[0048] In the embodiment shown in FIGS. 17-18, the first thermoformed layer 1704 is positioned in the dressing 104 with the structures on a surface of the first thermoformed layer 1704 facing the first barrier film layer 1702 and an opposing surface of the first thermoformed layer 1704 (without structures protruding therefrom) facing the first wound contact layer 1706. The structures of the first thermoformed layer 1704 separate the barrier film layer 1702 from the base surface of the first thermoformed layer 1704, thereby providing an open volume between the first thermoformed layer 1704 and the barrier film layer 1702. The open volume may form fluid pathways, airways, channels, etc., such that the first thermoformed layer 1704 and the structures protruding therefrom provide a manifold in the dressing 104 between the first thermoformed layer 1704 and the first barrier film layer 1702 that allows for the movement of air and fluid within the dressing 1700 and the communication of negative pressure throughout the dressing 1700 to a wound site.

[0049] The second thermoformed layer 1714 is positioned in the dressing 104 with the structures on a surface of the second thermoformed layer 1714 facing the second barrier fdm layer 1712 and an opposing surface of the second thermoformed layer 1714 (without structures protruding therefrom) facing the second wound contact layer 1716. The structures of the second thermoformed layer 1714 separate the second barrier fdm layer 1712 from the base surface of the second thermoformed layer 1714, thereby providing open volume between the second thermoformed layer 1714 and the barrier fdm layer 1712. The open volume may form fluid pathways, airways, channels, etc., such that the second thermoformed layer 1714 and the structures protruding therefrom provide a manifold in the dressing 1700 between the second thermoformed layer 1714 and the second barrier fdm layer 1712 that allows for the movement of air and fluid within the dressing 1700 and the communication of negative pressure throughout the dressing 1700 to a wound site.

[0050] In other embodiments, the thermoformed layers 1704, 1714 are oriented with the structures facing the wound contact layers 1706, 1716. In such embodiments, an open volume is provided between the thermoformed layers 1704, 1714 and the wound contact layer 1706, 1716 by the structures, such that a manifold is formed between the first thermoformed layer 1704 and the first wound contact layer 1706 and between the second thermoformed layer 1714 and the second wound contact layer 1716. Fluid (wound exudate, instillation fluid, etc.) and air can thereby be communicated throughout the dressing 1700.

[0051] The dressing 1700 includes a sealing cuff 1726 positioned at the wrist region 1724 of the dressing 1700. The sealing cuff 1726 is configured to apply a substantially air-tight seal around the extremity of a patient received by the dressing 1700 to establish a substantially air-tight volume defined by the barrier film layers 1702, 1712. The sealing cuff 1726 may include one or more adhesives (e.g., acrylic adhesive, silicone adhesive, etc.) to provide the seal. In some embodiments, the sealing cuff 1726 includes a collapsible structure configured to provide the seal when a negative pressure is applied to the sealing cuff 1726 by a pump (e.g., negative pressure pump 112 of therapy unit 102).

[0052] The dressing 1700 can be coupled to the therapy unit 102 of FIG. 1, for example by coupling a connection pad to the first barrier film layer 1702 and/or the second barrier film layer 1704, with the connection pad coupled to the vacuum tube 106 and, in some embodiments, the instillation tube 108. For example, a connection pad may be positioned over a hole in the first barrier film layer 1702 or the second barrier film layer 1704, with the hole having a diameter in a range between approximately 3 millimeters and approximately 20 millimeters. The hole may be formed by a caregiver during application of the dressing 1700, such that the position of the connection pad on the dressing 1700 is customizable. For example, a caregiver may place the connection pad at a position displaced from the wound to facilitate clear viewing of the wound through the transparent dressing 1700 and to provide comfort for the patient.

[0053] The negative pressure pump 112 can then be operated to draw air and/or fluid out of the dressing 1700 to establish a negative pressure at the dressing 1700. When a negative pressure is established at the dressing 1700, the barrier film layers 1702, 1712 are pulled inwards towards the patient and toward the thermoformed layers 1704, 1714. The structures on the surface of the thermoformed layers 1714, 1704 prevent the barrier film layers 1702, 1712 from sealing fully against the base surfaces of the thermoformed layers 1704, 1714 when pulled inwards by the negative pressure, instead ensuring that an open volume (channels, pathways, etc.) is provided between the thermoformed layers 1714, 1704 and the barrier film layers 1702, 1712. Negative pressure can thereby be provided substantially uniformly across the extent of the dressing 1700. Fenestrations through the thermoformed layers 1704, 1714 allow the negative pressure to be communicated to the wound contact layers 1706, 1716 and to the patient’s anatomy (e.g., to a wound) via the aligned fenestrations (of the thermoformed layers 1704, 1715) and perforations (of the wound contact layers 1706, 1716). The dressing 1700 is thereby also configured such that wound exudate, instillation fluid, or other fluid or debris can to flow between a wound and the therapy unit 102.

[0054] Referring now to FIG. 19, illustrations of a knuckle flexion point 1740 of the dressing 1700 are shown, according to an exemplary embodiments. The illustration includes a first frame showing the knuckle flexion points 1740 in an unbent state and a second frame showing the knuckle flexion points 1740 when bent. The knuckle flexion point 1740 include multiple thermoformed folds 1900.

In the example shown, the knuckle flexion point 1740 includes three thermoformed folds 1900. At each thermoformed fold 1900, the barrier film layer 1702, the thermoformed layer 1704, and the wound contact layer 1706 are bent (folded) to provide extra material at the thermoformed fold 1900 when the dressing is ‘straight’ (e.g., fingers unbent) as shown in the first frame of FIG. 19. When the dressing is ‘bent’ (e.g., fingers bent or clenched), for example under the force of a patient moving the patient’s finger within the dressing 1700 (e.g., with a knuckle pushing into the knuckle flexion point 1740 as shown in the second frame of FIG. 19), the extra material at the thermoformed fold 1900 is unfolded and allows the layers 1702, 1704, 1706 to expand to allow bending of the dressing 1700.

For example, the thermoformed folds 1900 may be configured to allow the dressing 1700 to bend by up to ninety degrees at the knuckle flexion point 1740. Knuckle flexion points 1740 may be places in positions on the dressing 1700 corresponding to joints (e.g., knuckles)

[0055] Referring now to FIG. 20, a hand dressing 2000 is shown, according to an exemplary embodiment. The hand dressing 2000 can be used with the NPWT system 100 of FIG. 1. The hand dressing 2000 includes the first barrier layer 1702, the first thermoformed layer 1704, the first wound contact layer 1706, the second barrier layer 1712, the second thermoformed layer 174, and the second wound contact layer 1716, configured similar to or the same as described above for FIG. 20, with variations described in the following. The hand dressing 2000 is also formed having a palm region 1720 and five digit regions 1722 as described above.

[0056] As shown in FIG. 20, each digit region 1722 of the dressing includes a series of thermoformed folds 1900 positioned along the entire length thereof. For example, the thermoformed folds 1900 may be spaced approximately equidistantly along the length of the digit regions 1722 and may be oriented substantially perpendicular to the length of the digit regions 1722. For example, in some embodiments, each digit region 1722 includes a number of thermoformed folds 1900 in a range between ten and forty. In other embodiments, equal to or less than ten folds are used (e.g., 10, 9, 8, 7, etc.). The digit regions 1722 may thereby configured to allow substantially free movement of digits positioned in the dressing 2000.

[0057] In the embodiment of FIG. 20, to facilitate communication of negative pressure to the distal tips of the digit regions 1722, and to facilitate movement of wound exudate and/or other fluid away from the distal tips of the digit regions 1722, the digit regions 1722 include zig-zag pathways 2002 formed by the structures on the surface of the first thermoformed layer 1704 (and, in some embodiments, on the second thermoformed layer 1714). Each zig-zag pathway 2002 include a pair of walls (ridges) formed on the first thermoformed layer 1704 and spaced apart by a width that defines an open space through which air and fluid can flow. The walls of the zig-zag pathways 2002 may be broken or perforated in multiple places to allow for movement of air and fluid into and out of the zig zag pathways 2002. Each zig-zag pathway includes substantially-straight walls separated by comers, such that the zig-zag pathway 2002 changes direction several times along a length of a digit region 1722. The zig-zag pathways may change directions at positions that correspond to knuckles of the patient’s fingers receivable by the digit region 1722. Each zig-zag pathway 2002 transverses multiple thermoformed folds 1900. The zig-zag design of the zig-zag pathways 2002 facilitates the pathways 2002 in maintaining an open volume within the dressing as the folds 1900 are repeatedly extended and re-fold and in various bent, unbent, or partially bent states of the dressing 2000. In some embodiments, the folds 1900 are broken/omitted along the zig-zag pathways 2002.

[0058] In the example of Fig. 20, the palm region 1720 includes structures on the thermoformed layers 1704, 1714 which are arranged in a similar manner as in FIG. 17, i.e., spaced approximately equidistantly and formed as bumps or pillars as described above. Manifolding may thereby be provided across the palm region 1720 to allow fluid communication to, from, and between the digit regions 1722. A connection pad may be placed in the palm region 1720 to couple the dressing 2000 to the therapy unit 102.

[0059] Although the examples shown in the FIGURES are configured for use in treating hands (e.g., glove-shaped dressings), variations and adaptations for use with other extremities are within the scope of the present disclosure. For example, the dressings 104, 1700, 2000 may be adapted to have a sock shape or other form suitable for treating a food of a patient. As another example, the dressings 104, 1700, 2000 may be adapted to have a form configured to fit over an amputation stump (i.e., a distal end of a partial limb of a patient). As another embodiment, the dressings 104, 1700, 2000 may be formed as sleeves having sealing rings/cuffs on two ends, for example for use to cover a middle area along a limb of a patient (e.g., forearm, upper arm, lower leg, upper leg, knee, elbow, etc.). All such variations are within the scope of the present disclosure.

Collapsible Cuff for Sealing Extremity Dressings

[0060] One challenge associated with extremity dressings (i.e., dressings configured to treat hands, feet, amputation stumps, other extremities) for negative pressure wound therapy is achieving a sufficiently air-tight seal around the extremity at one or more ends of the dressing. Referring generally to FIGS. 21-27, described in detail below, improved systems and methods are shown for establishing a seal around an extremity to facilitate negative pressure wound therapy.

[0061] Referring now to FIGS. 21-22, a collapsible cuff for sealing extremity dressings is shown, according to exemplary embodiments. A dressing 2100 is shown that includes a treatment portion (extremity section) 2102 coupled to a collapsible cuff 2104. The treatment portion 2102 is configured to allow a negative pressure to be established at a wound on an extremity of a patient when the collapsible cuff 2104 is sealed around the extremity. The treatment portion 2102 may correspond to the central region 312 and peninsular projections 314 of the dressing 104 described above, or palm region 1720 and digit regions 1722 of dressing 1700 described above. For the sake of example, FIGS. 21-22 show, the treatment portion 2102 as including a first manifold layer 300, second manifold layer 302, first barrier layer 304, second barrier layer 306, first fenestrated film layer 308, and second fenestrated film layer 310 as shown in FIGS. 4-6 and described in detail below. The collapsible cuff 2104 may also be used with other embodiments of the treatment portion 2102.

[0062] The collapsible cuff 2104 is positioned at an open end of the treatment portion 2102, for example at the wrist region 1724 of the dressing 1700 or the wrist portion 320 of the dressing 104.

The cuff 2104 defines an opening 2110 through which the extremity can be inserted to reach the treatment portion 2102. As described in detail below, the collapsible cuff 2104 is configured to collapse circumferentially when air is removed from the collapsible cuff 2104, thereby pulling inwards to seal against an extremity that extends through the collapsible cuff 2104 and into the treatment portion 2102. The collapsible cuff 2104 may thereby provide a reliable seal that is easy for a single caregiver to establish in an efficient manner.

[0063] As shown in FIGS. 21-22, the collapsible cuff 2104 includes an inner film layer 2200 formed in a loop and an outer film layer 2202 concentric with the inner film layer 2200. The inner film layer 2200 and the outer film layer 2202 are coupled together to define an interior volume 2204 of the collapsible cuff 2104 therebetween. The interior volume 2204 is substantially ring-shaped. A collapsible manifold structure 2206 is positioned in the interior volume 2204 between the inner film layer 2200 and the outer film layer 2202.

[0064] The inner film layer 2200 may be composed of a polyurethane film, for example having a thickness of approximately 80 micrometers. The outer film layer 2202 may also be composed of a polyurethane film, for example having a thickness of approximately 80 micrometers. In other embodiments the inner film layer 2200 and the outer film layer 2202 have different thickness (e.g., such that the outer film layer 2202 is thicker than the inner film layer 2200).

[0065] The inner film layer 2200 and the outer film layer 2202 may be bonded together by radio frequency or high frequency welding or by ultrasonic welding. The inner film layer 2200 and the outer film layer 2202 are welded together along edges of the inner film layer 2200 and the outer film layer 2202, such that an interior volume 2204 is left open between the inner film layer 2200 and the outer film layer 2202. The manifold structure 2206 may be positioned between the inner film layer 2200 and the outer film layer 2202 before the inner film layer 2200 is welded to the outer film layer 2202, such that the welding process results in the manifold structure 2206 being confined between the inner film layer 2200 and the outer film layer 2202. In other embodiments, the inner film layer 2200 and the outer film layer 2202 are coupled together by heat bonding or using an adhesive.

[0066] The collapsible manifold structure 2206 is configured to facilitate the distribution of pressure throughout the cuff 2104 by allowing air and fluid flow therethrough. The collapsible manifold structure 2206 may include an open-celled foam, for example a polyurethane foam. In some embodiments, the foam of the manifold structure2206 has approximately 45 pores per inch. In some embodiments, a felted foam may be used. The felted foam may be felted (i.e., heated and compressed) by a factor of three, five, seven, etc., for example such that the foam of the manifold structure has approximately 135 pores per inch, approximately 225 pores per inch, approximately 315 pores per inch, etc. in various embodiments. In other embodiments, a closed cell foam is used.

[0067] The collapsible manifold structure 2206 is also configured to collapse (compress, contract, reduce in dimension, etc.) when a negative pressure is established in the cuff 2104, i.e., when air is removed from the cuff 2104. A length of the collapsible manifold structure 2206 may be defined as extending around the circumference of the cuff 2104, with a thickness of the manifold structure 2206 oriented along a radial direction of the cuff 2104. The collapsible manifold structure 2206 may be shaped to facilitate the manifold structure 2206 in reducing in length under negative pressure by a factor multiple times greater than a reduction in the thickness of the manifold structure 2206 under negative pressure. For example, the collapsible manifold layer may have cut-outs (holes, channels, openings, etc.) extending through the manifold structure 2206 that contract to allow for length-wise collapse of the manifold structure 2206. An example of the collapsible manifold structure is shown in FIG. 25 and described in detail with reference thereto.

[0068] The collapsible cuff 2104 is also shown to include a connection pad 1108 configured to couple the collapsible cuff 2104 to a vacuum tube 106 such that the interior volume 2204 of the cuff 2104 is in fluid communication with the vacuum tube 106. The interior volume 2204 may be placed in fluid communication with the therapy unit 102 via the tube 106. For example, a negative pressure pump 112 as described above may be in fluid communication with the interior volume 2204 of the cuff 2104 via the tube 106 and the connection pad 1108. The negative pressure pump 112 can then operate to remove air from the interior volume 2204 of the cuff 2104, thereby establishing a negative pressure in the cuff 2104. In some embodiments, the connection pad 1108 is also coupled to an instillation tube 108 to facilitate instillation therapy as described with reference to FIGS. 1-2.

[0069] Furthermore, as shown in FIG. 21-22, the dressing 2100 includes a regulator valve 2106 configured to control fluid flow between the interior volume 2204 of the cuff 2104 and the treatment portion 2102 of the dressing 2100. For example, the regulator valve 2106 may define a channel between the interior volume 2204 of the cuff 2104 and a manifold layer of the treatment portion 2102 of the dressing 2100. In some embodiments, the regulator valve 2106 is configured to remain closed (i.e., such that fluid cannot flow between the interior volume 2204 and the treatment portion 2102) when the pressure in the cuff 2104 is less than a threshold negative pressure in absolute value. In such embodiments, the regulator valve 2106 may be configured to open (i.e., such that fluid can flow between the interior volume 2204 and the treatment portion 2102) when the pressure in the cuff 2104 is greater than the threshold negative pressure in absolute value. In some examples, the threshold negative pressure is approximately 100 mmHg. In such a case, for example, if the therapy unit 102 controls the pump 112 to maintain a negative pressure of approximately 125 mmHg at the dressing 104, the regulator valve 2106 remains open. In such case, fluid can flow from the treatment portion 2102 of the dressing 2100 to the therapy unit 102 along a path through the regulator valve 2106, along the cuff 2104 to the connection pad 1108, and from the connection pad 1108 to the therapy unit 102 via the tube 106. Negative pressure therapy is thereby supplied at the treatment portion 2102 via the cuff 2104.

[0070] In other embodiments, a second connection pad is provided at the treatment portion 2102 and is coupled to another section of tubing in fluid communication with the therapy unit 102. In such a case, the regulator valve may be omitted or may be external to the dressing 2100. An example of such an embodiment is shown in FIGS. 26-27 and described in detail with reference thereto below.

[0071] FIGS. 21-22 also show that a patient interface layer 2208 may be included on a patient facing surface of the inner film layer 2200. The patient interface layer 2208 is configured to contact a patient’s skin when the dressing 2100 is applied to the patient’s extremity and achieve a seal between the inner film layer 2200 and the patient’s skin. In some embodiments, the patient interface layer 2208 includes a perforated silicone material (e.g., silicone trilaminate). In some embodiments, the patient interface layer 2208 includes a polyurethane hydrogel. The patient interface layer 2208 may be perforated to allow for moisture transmission therethrough, for example such that the moisture vapor transmission rate of the dressing 2100 is greater than approximately 250 g/m²/day. In some embodiments, the patient interface layer 2208 includes a heavy coat weight acrylic adhesive, for example as provided in the V.A.C.® Gel kit by ACELITY™ In some embodiments, the patient interface layer 2208 includes a multi-layered structure that combines an acrylic adhesive and a silicone layer such that the acrylic adhesive can interface with the patient through perforations in the silicone layer. [0072] In some embodiments, a redundant (e.g., extra, additional) adhesive strip may also be provided in some embodiments to support, augment, back-up, etc. the seal between the cuff 2104 and the extremity. For example, a strip of polyurethane drape material may be provided with an adhesive (for example, a silicone adhesive, an acrylic adhesive, or a combination thereof) and positioned around the extremity and the cuff 2104 to adhere to both the extremity and the cuff 2104.

[0073] Referring now to FIG. 23, another cross-sectional view of the cuff 2104 is shown, according to an exemplary embodiments. As in FIGS. 21-22, the cuff 2104 is shown to include an inner fdm layer 2200 coupled to an outer fdm layer 2202 to define an interior volume 2204 which contains a collapsible manifold structure 2206.

[0074] However, in the example ofFIG. 23, the cuff2104 is formed as a first half 2300 and a second half 2302 rather than as a single continuous loop as in other embodiments. To facilitate manufacturing of the cuff 2104 (e.g., to simplify welding of the outer film layer 2202 to the inner film layer 2200), the cuff 2104 may be manufactured as a first half 2300 and a second half 2302 and then welded together at two ends in to form a loop (ring) that defines the cuff 2104. The first half 2300 and the second half 2302 may each have a substantially rectangular shape. Each of the first half 2300 and the second half 2302 includes a portion of the inner film layer 2200 and a portion of the outer film layer 2202 welded together to define a portion of the interior volume 2204 which contains a portion of the collapsible manifold structure 2206. For example, FIG. 23 shows the first half 2300 coupled (e.g., radio-frequency welded, high-frequency welded, ultrasonically welded, heat bonded) to the second half 2302 at two welds 2304. The patient interface layer 2208 may be applied before or after the first half 2300 and the second half 2302 are coupled together in various embodiments. While two halves 2300, 2302 are shown in FIG. 23, in other embodiments the cuff 2104 is formed in thirds, quarters, etc. coupled to form a ring as described for the halves 2300, 2302 of FIG. 23.

[0075] To allow fluid communication between the first half 2300 and the second half 2302 of the cuff 2104, the cuff 2104 ofFIG. 23 includes a connection conduit 2306 that connects the interior volumes 2204 of the first half 2300 and the second half 2302. The connection conduit 2306 may be formed as a polyurethane tube or extruded polymer that extends from the first half 2300 to the second half 2302 and provides an interior bore (channel, pathway, etc.) that allows fluid to flow between the interior volumes 2204 of the first half 2300 and the second half 2302. That is, the connection conduit 2306 bypasses a weld 2304 to unify the interior volumes 2204 of the first half 2300 and the second half 2302. In some embodiments, two or more connection conduits 2306 are included.

[0076] In some embodiments, the connection conduit 2306 is coupled to (e.g., integrally formed with) the regulator valve 2106. In such embodiments, the connection conduit 2306 joins the treatment portion 2102 and both the first half 2300 and the second half 2302 are fluidly communicable with one another via the connection conduit 2306. Combination of the connection conduit 2306 and the regulator valve 2106 may reduce the number of discrete parts to be manufactured and coupled to the dressing 2100 during in manufacturing and may improve fluid flow dynamics of the dressing 2100. In the embodiment shown, the connection pad 1108 couples the vacuum tube 106 to the cuff 2104 at a point displaced from the connection conduit 2306. In other embodiments, the vacuum tube is coupled to the cuff 2104 via the connection conduit 2306 (i.e., such that the connect pad 1108 is replaced by or is integrated with the connection conduit 2306).

[0077] Referring now to FIG. 24, a storyboard-style illustration of operation of the collapsible cuff 2104 is shown, according to an exemplary embodiment. The first frame 2400 illustrates the collapsible cuff 2104 as configured for initial application to a patient. Accordingly, the first frame 2400 shows the collapsible cuff 2104 with the interior volume 2204 of the cuff 2104 at approximately atmospheric pressure. The collapsible cuff 2104 may be distributed, stored, etc. in the state shown in the first frame 2400. With the interior volume 2204 of the cuff 2104 at approximately atmospheric pressure, a length of the collapsible manifold structure 2206 is substantially maximized and the circumference of the cuff 2104 is substantially maximized. In the state shown in the first frame 2400, the cuff 2104 is configured to allow an extremity of a patient to be inserted through an opening 2110 defined by the cuff 2104 to reach the treatment portion 2102 of the dressing 2100. In the state shown in the first frame 2400, the opening 2110 may be sufficiently large to allow the extremity to freely pass through the cuff 2104.

[0078] Removal of air from the cuff 2104 is initiated between the first frame 2400 and the second frame 2402. For example, a negative pressure pump 112 may operate to remove air from the cuff 2104 via a tube 106. In the embodiments shown herein, air is removed from the cuff 2104 by an electrically-powered device. In other embodiments, a manual pump may be included to allow a user to manually pump air out of the cuff 2104.

[0079] The second frame 2402 shows the cuff 2104 during removal of air from the cuff 2104. As compared to first frame 2400, the second frame 2402 shows that the collapsible manifold structure 2206 is partially contracted in length, thereby reducing a circumference of the cuff 2104. It follows that a size of the opening 2110 defined by the cuff 2104 is reduced, as is a radius of the cuff 2104. [0080] As more air is removed from the cuff 2104 (i.e., as the pressure in the interior volume 2204 of the cuff 2104 reaches lower and lower values), the collapsible manifold structure 2206 continues to contract (collapse) in length. Eventually, for example when a target pressure is reached at the cuff 2104, the cuff 2104 reaches atarget circumference as shown in the third frame 2406. In some cases, the target pressure is a negative pressure associated with effective negative pressure wound therapy, for example approximately 125 mmHg. In some cases, the target pressure is variable based on the target circumference, which may vary with the size of the extremity inserted through the cuff 2104. For example, a lower pressure may be required to seal the cuff 2104 against larger extremities as compared to smaller extremities. In some embodiments, the target pressure may be adjusted based on patient comfort preferences. In some embodiments, the therapy unit 102 may be configured to perform a test to check whether a sufficient seal has been established between the cuff 2104 and the extremity to confirm whether a sufficient amount of pressure has been provided at the cuff 2104. [0081] Accordingly, the third frame 2406 illustrates the cuff 2104 in a contracted (collapsed) state suitable for providing a seal between the extremity and the dressing 2100 that allows negative pressure wound therapy for the extremity. In some embodiments, a pump runs periodically to maintain the pressure in the cuff 2104 within an acceptable error of the target pressure for the cuff 2104, thereby maintaining the seal between the extremity and the dressing 2100.

[0082] In some embodiments, a circumference of the cuff 2104 can be reduced by up to approximately 40% between the state shown in the first frame 2400 of FIG. 24 and the fully- contracted state of the third frame 2406 of FIG. 24. Accordingly, the radius of the opening 2110 defined by the cuff 2104 may be reduced by up to approximately 40% and the area of the opening may be reduced by up to approximately 65%. In other words, an area of the opening 2110 as shown in the third frame 2406 may be approximately 35% the size shown in the first frame 2400. As one example, the cuff 2104 may thereby be configured to allow a patient’s hand (or foot) to pass freely through the cuff 2104 before the cuff 2104 is collapsed to seal against the patient’ s wrist (or ankle), including where the hand (or foot) has significantly larger dimensions than the wrist (or ankle). This can help reduce pain and other challenges associated with squeezing, pushing, forcing, etc. an injured hand through a relative small opening.

[0083] Referring now to FIG. 25, a profile view of the collapsible manifold structure 2206 is shown, according to an exemplary embodiment. In the orientation shown in FIG. 25, a length dimension of the collapsible manifold structure 2206 is oriented horizontally in the drawing, a width dimension is oriented vertically in the drawing, and a thickness of the collapsible manifold structure 2206 is normal to the plane of the drawing. When included in the dressing 2100 as shown in FIGS. 21-22, the collapsible manifold structure 2206 may be curved into a loop such that a first end 2502 of the manifold structure 2206 is proximate an opposing second end 2504 of the manifold structure 2206.

The manifold structure 2206 is flexible. The manifold structure 2206 may have a length of approximately 290 millimeters, a width of approximately 25 millimeters, and a thickness of approximately 10 millimeters.

[0084] The collapsible manifold structure 2206 is formed with a pattern configured to facilitate the manifold structure 2206 in collapsing (contract, compress, etc.) in the length dimension. In particular, the manifold structure 2206 includes a pattern of “cut-outs” 2506, i.e., holes, channels, spaces, openings, etc. that extend through the collapsible manifold structure 2206. The cut-outs extend through the collapsible manifold structure 2206 in the thickness-direction, i.e., perpendicular to both the length and width of the manifold structure 2206.

[0085] In the example shown, the cut-outs 2056 are diamond-shaped and arranged along a center line of the manifold structure 2206 and may be spaced approximately equidistantly. Each cut-out may extend for approximately half of a width of the manifold structure 2206 and approximately 1% of the length of the manifolding layer. In the example of FIG. 25, the manifold structure 2206 includes 37 cut-outs, although different numbers may be used in various embodiments (e.g., between approximately 30 and approximately 50).

[0086] The manifold structure 2206 also includes a pattern of notches 2508 arranged along the two opposing sides of the manifold structure 2206 which define the length and thickness dimensions of the manifold structure 2206. Each notch 2508 defines open space that extends entirely across the thickness dimension of the manifold structure 2206 and extends partially into the width dimension of the manifold structure 2206 (e.g., across approximately 25% of the width of the manifold structure). Each notch 2508 also has a length dimension of approximate 2% of the length of the manifold structure 2206, with the example of FIG. 25 showing 38 notches on each of the relevant sides of the manifold structure 2206. Each notch 2508 is shown to be approximately triangular, with a narrower end of the notch pointing into the manifold structure.

[0087] In the example shown, each notch 2508 is aligned with another notch 2508 positioned on the opposing side of the manifold structure 2206. Additionally, the notches 2508 are positioned between the cut-outs 2506 in the length-wise direction (i.e., aligned with portions of manifolding material between the cut-outs 2506). Accordingly, any point along substantially the full length of the manifold structure 2206 corresponds to either a cut-out 2506 or a pair of notches 2508. In other words, the manifold structure 2206 may thereby be characterized as a series of open parallelograms joined in series at vertices thereof.

[00882] The open volume created by the cut-outs 2506 and the notches 2508 provide space for collapse of the manifold structure 2206. Under atmospheric pressure, the cut-outs 2506 and the notches 2508 are filled with air. When air is removed from the cuff 2104 as described above, at least some of the air in the cut-outs 2506 and the notches 2508 is evacuated, leaving a partial vacuum. The manifold structure 2206 is pulled into this vacuum to fill the space previously occupied by the removed air. Accordingly, when a target negative pressure is established (e.g., as shown in the third frame 2406 of FIG. 24), the manifold structure 2206 is compressed to substantially fill the cut-outs 2506 and notches 2508. In particular, the lengthwise dimensions of the cut-outs 2506 and notches 2508 may be significantly reduced under negative pressure.

[0089] In the example shown, the pattern of FIG. 25 allows the manifold structure 2206 to reduce in length under negative pressure by an amount in a range between approximately 35% and approximately 45%, for example by approximately 38.5%. The width dimension of the manifold structure 2206 may be reduced by an amount in a range between approximately 5% and 10%, for example 6.7 %. Accordingly, for example, the manifold structure 2206 may be configured to reduce in length by a first percentage and reduce in width by a second percentage, where the first percentage is greater than the second percentage (e.g., at least four times greater).

[0090] Referring now to FIGS. 26-27, views of an alternative embodiment of the dressing 2100 are shown, according to an exemplary embodiment. As for FIGS. 21-25, the dressing 2100 of FIGS. 26- 27 includes a treatment portion 2102 and a collapsible cuff 2104, which may be configured as above with the exception of the differences noted below with reference to FIGS. 26-27. In particular, FIGS. 26-27 show an embodiment where multiple connection pads are used to allow tubes to be connected to the dressing 2100 at multiple locations.

[0091] FIG. 26 shows a view of a first side of the dressing 2100. FIG. 26 shows a first connection pad 2602 is positioned on the collapsible cuff 2104 on the first side of the dressing 2100, while FIG.

27 shows that a second connection pad 2604 on the second side of the dressing 2100. FIG. 26 also shows a third connection pad 2606 positioned on the treatment portion 2102 of the dressing 2100. [0092] A vacuum tube 106 is provided that can provide for the flow of fluid between the dressing 2100 and a therapy unit 102. In the example of FIG. 26, the vacuum tube 106 extends from a first joint 2610 to the therapy unit 102. The first joint 2610 is a three-way joint that places the vacuum tube 106 in fluid communication with tubing that runs to the first connection pad 2602 and the second connection pad 2604 and to tubing that runs to the third connection pad 2606. Tubing extends from the first joint 2610 to a second joint 2608. The second joint 2608 is connected in fluid communication with a first tube 2612 that runs to the first connection pad 2602 and a second tube 2614 that runs to the second connection pad 2604. The combination of the first joint 2610, the second joint 2608, the first tube 2612, the second tube 2614, the first connection pad 2602 and the second connection pad 2604 thereby serve to communicate negative pressure from a therapy unit 102 to both sides of the cuff 2104. The embodiment of FIG. 26 may thereby be suitable for use in place of the connection conduit 2306 of FIG. 23.

[0093] FIGS. 26-27 also show that the first joint 2610 places the first tube 2612 and the second tube 2614 (and, accordingly, the vacuum tube 106) in fluid communication with a third tube 2616 that runs to the third connection pad 2606 at the treatment portion 2102 of the dressing 2100. The third tube 2616 includes a regulator valve 2106 configured as described above. That is, the regulator valve 2106 may allow for fluid communication from the third connection pad 2606 to the first tube 2612 and the second tube 2614 when negative pressure is above a threshold value, while preventing fluid communication from the third connection pad 2606 to the first tube 2612 and the second tube 2614 when negative pressure is below the threshold value. The example of FIGS. 26-27 may thereby achieve similar fluid and pressure behavior as in the examples of FIGS . 21-25 with the regulator valve 2106 and conduits between portions of the dressing 2100 provided externally to the dressing 2100. [0094] Various embodiments of the dressing 2100 are possible. For example, in some embodiments a valve or other mechanism to seal the cuff 2104 when the cuff 2104 reaches sufficient pressure to seal against the patient’s extremity. The tube(s) connected to the cuff 2104 can then be disconnected, and the cuff 2104 may remain at negative pressure without further operation of a pump. In such an embodiment, a therapy unit 102 can then be placed in fluid communication with the treatment portion 2102 without fluid passing through the cuff 2104 or tubing associated with the cuff 2104. For example, the cuff 2104 can be compressed and sealed, and the tubing can be connected to the treatment portion 2102 as shown in FIGS. 11 and 16. [0095] As another example, in some embodiments, the dressing 2100 provides an indication to a user regarding whether the cuff 2104 is sealed and/or whether therapy is being delivered to the treatment portion. For example, the regulator valve 2106 may include a bellows-type valve that protrudes from the dressing when the threshold pressure has not been reached (e.g., when the regulator valve 2106 is closed) and is noticeably retracted when the threshold pressure has been reached (e.g., when the regulator valve 2106 is open).

[0096] In other embodiments, a sensor may be included and data from the sensor may be used to provide visual or audio notifications regarding pressure levels at the dressing (e.g., via an input/output device 118 of the therapy device 102). For example, the regulator valve 2106 may include sensors to monitor pressure, humidity, and/or pH at the valve. The regulator valve 2106 may also include wireless communications circuitry configured to wirelessly transmit the sensed data out of the dressing 2100 (e.g., to the therapy unit 102), for example via WiFi, Bluetooth, Near Field Communication, etc..

[0097] As another example, in some embodiments, the collapsible cuff 2104 is manually by operation of a manual pump. In such an embodiment, the regulator valve 2106 may be omitted. The collapsible cuff 2104 may be brought to negative pressure using the manual pump to seal the cuff 2104 around an extremity. In some such embodiments, a check valve is included underneath a secondary sealed chamber which is connected to the ambient air via a vent hole. The secondary sealed chamber may house a material with a certain amount of rebound/resiliency, for example a reticulated polyurethane foam. In such embodiments, when the chamber is compressed, air is evacuated through the vent hole. The secondary sealed chamber naturally rebounds to draw air through the check valve and out from the sealing ring below. This allows for evacuation of the collapsible cuff 2104 to allow the collapsible cuff 2104 to be sealed around a patient’s extremity without requiring the collapsible cuff 2104 to be part of the fluid pathway between the treatment portion 2102 and the therapy unit 102.

[0098] As another example, in some embodiments the cuff 2104 may include a superabsorbent polymer. For example, the manifold structure 2206 may include or be replaced by a superabsorbent in a manifolding “tea-bag” structure (e.g., where superabsorbent particles are contained within a pouch of non-woven materials, in some cases along with manifolding foam material). This may allow the cuff 2104 to absorb and store a large amount of fluid. The material of the outer film layer 2202 may be configured to allow evaporation of fluid therethrough to the ambient environment. In some embodiments, windows of a material having a high moisture vapor transmission rate may be provided at the outer film layer 2202. In some such embodiments, a hydrophobic filter is positioned at the connection pad 1108 to prevent fluid from being drawn into the tube 106. This is particularly useful in embodiments where the therapy unit 102 is not configured to receive fluid from the dressing 100, and instead wound fluid is evaporated from the dressing 2100, for example via the cuff 2104. [0099] As yet another example, in some embodiments the cuff 2104 is inflated rather than deflated. In such embodiments, the cuff 2104 is not fluidly communicable with the treatment portion 2102. An electrical or manual pump may be used to inflate the cuff 2104. In some embodiments, the exhaust from the negative pressure pump 112 of the therapy unit 102 can be used to inflate the cuff 2104. In such embodiments, the cuff 2104 is configured to expand when inflated to reduce an area of the opening 2110 defined by the cuff 2104, thereby allowing the cuff 2104 to be sealed against an extremity.

[0100] In some embodiments, an additional adhesive strip may be applied after the cuff 2104 has been sealed against the extremity. Multiple methods and systems for sealing the dressing 2100 to the extremity may be used together. In fact, it should be understood that all combinations of the various embodiments described herein, including various materials, dressings, manifolds, shapes, dimensions, patterns, etc., are within the scope of the present disclosure.

Configuration of Exemplary Embodiments

[0101] Although the figures show a specific order of method steps, the order of the steps may differ from what is depicted. Also two or more steps can be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various connection steps, calculation steps, processing steps, comparison steps, and decision steps.

[0186] The construction and arrangement of the systems and methods as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements can be reversed or otherwise varied and the nature or number of discrete elements or positions can be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps can be varied or re sequenced according to alternative embodiments. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

[0187] As utilized herein, the terms “approximately,” “about,” “substantially”, and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A negative pressure wound therapy system, comprising: a pump; a dressing fluidly communicable with the pump, the dressing comprising: a treatment portion configured to receive an extremity of a patient; and a cuff positioned at a first end of the treatment portion and configured to extend around the extremity of the patient; wherein the pump is operable to remove air from an interior of the cuff; wherein the cuff is configured to contract circumferentially when the air is removed from the cuff.

2. The negative pressure wound therapy system of Claim 1, wherein the cuff is configured to provide a seal between the cuff and the extremity when the cuff extends at least partially around the extremity and the air is removed from the cuff.

3. The negative pressure wound therapy system of Claim 1, wherein the cuff comprises: an external film layer; an internal film layer sealed to the external film layer along a periphery of the cuff to define the cuff, an interior volume of the cuff defined by the external film layer and the internal film layer; a manifold layer positioned in the interior volume of the cuff and sealed between the external film layer and the internal film layer; and an adhesive layer coupled to the internal film layer, the internal film layer positioned between the manifold layer and the adhesive layer.

4. The negative pressure wound therapy system of Claim 3, wherein the adhesive layer is perforated and comprises silicone.

5. The negative pressure wound therapy system of Claim 1, wherein the cuff comprises a manifold layer extending along a circumference of the cuff, the manifold layer comprising a foam material having a plurality of diamond-shaped cut-outs.

6. The negative pressure wound therapy system of Claim 1, wherein the interior of the cuff comprises a manifold layer having a length defining a circumference of the cuff and a width defining a thickness of the cuff; wherein, when the air is removed from the cuff by the pump, the length of the manifold layer is reduced by a first percentage and the width is reduced by a second percentage, the first percentage greater than the second percentage.

7. The negative pressure wound therapy system of Claim 5, wherein the first percentage is at least four times greater than the second percentage.

8. The negative pressure wound therapy system of Claim 1, wherein the treatment portion is glove -shaped.

9. The negative pressure wound therapy system of Claim 1, comprising a tube extending from the pump and fluidly communicable with the interior of the cuff via a connection pad positioned on an external surface of the cuff.

10. The negative pressure wound therapy system of Claim 1, wherein the pump is operable to remove air from a volume defined by the treatment portion when the seal is established between the cuff and the extremity.

11. The negative pressure wound therapy system of Claim 1, comprising a valve positioned between the cuff and the treatment portion, the valve configured to: prevent airflow between the interior of the cuff and the treatment portion when a negative pressure in the cuff is at less than a threshold absolute value; and allow airflow between the interior of the cuff and the treatment portion when the negative pressure in the cuff is at greater than the threshold absolute value.

12. The negative pressure wound therapy system of Claim 1, wherein the treatment portion comprises an external film layer, a manifold layer, and a wound contact layer.

13. A method of treating a wound at an extremity of a patient, comprising: providing a dressing comprising a treatment portion and a cuff positioned at a first end of the treatment portion; inserting the extremity of the patient through the cuff and into the treatment portion; establishing a seal between the cuff and the extremity by: providing a pump in pneumatic communication with the cuff; and operating the pump to remove air from the cuff to cause the cuff to contract circumferentially.

14. The method of Claim 13, further comprising operating the pump to remove air from a space between the treatment portion and the extremity to provide a negative pressure to the extremity at the treatment portion.

15. The method of Claim 14, comprising adhering the cuff to the patient using an adhesive coupled to the cuff.

16. The method of Claim 14, wherein operating the pump to remove air from the cuff to cause the cuff to contract circumferentially comprises causing a manifold layer of the cuff to contract, the manifold layer provided with a plurality of cut-outs configured to facilitate contraction of the manifold layer.

17. The method of Claim 16, wherein the cut-outs are diamond-shaped.

18. A cuff for a wound therapy system, the cuff comprising: a first film formed as a loop; a second film concentric with the first film and sealed to the first film to define a volume between the first film and the second film; and a foam structure positioned in the volume between the first film and the second film, wherein the foam structure is configured to reduce in length when a negative pressure is established in the volume; wherein a reduction in length of the foam structure causes a reduction in circumference of the loop.

19. The cuff of Claim 18, wherein the foam structure comprises a plurality of holes therethrough configured to facilitate the reduction in length of the foam structure.

20. The cuff of Claim 19, wherein the plurality of holes are diamond-shaped.

21. The cuff of Claim 18, comprising an adhesive positioned on a surface first film outside of the volume.

22. The cuff of Claim 18, comprising a port positioned at the second film and configured to be coupled to a tube.

23. The cuff of Claim 18, wherein the cuff is configured to be coupled to a treatment portion of a dressing.

24. The cuff of Claim 23, further comprising a valve configured to regulate fluid communication between the treatment portion and the volume.

25. The cuff of Claim 18, wherein, when the negative pressure is applied, the reduction in length of the foam structure is greater than a reduction in width of the foam structure.

26. The cuff of Claim 18, wherein, when the negative pressure is applied, the reduction in length of the foam structure is greater than a reduction in thickness of the foam structure.