Patent Description:
One common location for a wound (e.g., a burn) 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.

One implementation of the present invention is a dressing for negative pressure wound therapy. 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. The plurality of felted foam strips occupy only a portion of the surface area of the barrier film layer and only a portion of the surface area of the wound contact layer.

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.

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.

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.

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.

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.

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.

Another implementation of the present invention is a wound therapy system. The wound therapy system includes a pump, a tube coupled to the pump, and dressing according to the invention coupled to the tube.

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.

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.

Another implementation of the present disclosure not in accordance with the claimed invention 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.

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.

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.

Referring to <FIG> and <FIG>, a negative pressure and instillation wound therapy (NPWTi) system <NUM> is shown, according to exemplary embodiments. <FIG> shows a perspective view of the NPWTi system <NUM>, according to an exemplary embodiment. <FIG> shows a block diagram of the NPWTi system <NUM>, according to an exemplary embodiment. The NPWTi system <NUM> is shown to include a therapy unit <NUM> fluidly coupled to a dressing <NUM> via a vacuum tube <NUM> and an instillation tube <NUM>. In the embodiments described herein, the dressing <NUM> is configured for use in treating one or more wounds on a patient's hand. The NPWTi system <NUM> is also shown to include an instillation fluid source <NUM> fluidly coupled to the instillation tube <NUM>. The NPWTi system <NUM> is configured to provide negative pressure wound therapy at a wound bed by reducing the pressure at the dressing <NUM> relative to atmospheric pressure. The NPWTi system <NUM> is also configured to provide instillation therapy by providing instillation fluid to the dressing <NUM>. By providing both negative pressure wound therapy and instillation therapy, the NPWTi system <NUM> is configured to facilitate wound healing. As described in detail below, the NPWTi system <NUM> is also configured to provide a physiotherapy mode that facilitates mobility, articulation, etc. of a patient's hand during treatment by the NPWTi system <NUM>. The NPWTi system <NUM> thereby facilitates wound healing while also allowing for functional rehabilitation of the hand and reducing the risk of contractures.

Although the examples described herein show a NPWTi system <NUM> configured to provide both negative pressure wound therapy and instillation therapy, in other embodiments the system <NUM> is configured to provide negative pressure wound therapy (NPWT) without instillation therapy.

The dressing <NUM> is coupleable to a wound bed, i.e., a location of a wound (e.g., sore, laceration, burn, etc.) on a patient. In the examples herein, the dressing <NUM> is configured to be placed on a hand of a patient to cover a wound bed located on the hand. The dressing <NUM> 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 <NUM>). The dressing <NUM> may be coupled to the vacuum tube <NUM> and the instillation tube <NUM>, for example to place the vacuum tube <NUM> and/or the instillation tube <NUM> in fluid communication with the wound bed. Embodiments of the dressing <NUM> are shown in <FIG> and described in detail with reference thereto.

The dressing <NUM> includes one or more sensors <NUM>. The one or more sensor(s) <NUM> are configured to measure one or more physical parameters at the dressing and provide the measurements to the control circuit <NUM>, 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) <NUM> include a humidity sensor configured to measure humidity at the dressing <NUM>, a moisture sensor configured to measure moisture at the dressing <NUM>, and a strain sensor configured to measure a strain on the dressing <NUM>. In some embodiments, the one or more sensor(s) <NUM> include one or more pH sensors to measure tissue pH or fluid pH.

The therapy unit <NUM> includes a negative pressure pump <NUM> (shown in <FIG> and obscured within the therapy unit <NUM> in the perspective view of <FIG>) 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 <NUM> via the vacuum tube <NUM>, thereby creating a negative pressure at the dressing <NUM>. The negative pressure pump <NUM> is fluidly communicable with the vacuum tube <NUM> and the dressing <NUM>. Wound exudate and/or other debris and/or fluids removed from the wound bed by the negative pressure pump <NUM> may be collected in a canister <NUM> located on the therapy unit <NUM>. The canister <NUM> may be removable from the therapy unit <NUM> to allow canister <NUM> to be emptied or replaced when the canister <NUM> fills with fluid and debris.

Operating the negative pressure pump <NUM> 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 <NUM> 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 <NUM> may be operated to provide various levels (amounts, values, etc.) of negative pressure at the wound bed (e.g., <NUM> mmHg, <NUM> mmHg, <NUM> mmHg, <NUM> mmHg, <NUM> mmHg, etc.) for example varying over time as part of a dynamic pressure control approach. In the embodiments described below, the negative pressure pump <NUM> is configured to operate, as controlled by the control circuit <NUM>, to provide a first level of negative pressure at the wound bed corresponding to a wound therapy mode (e.g., <NUM> mmHg) and a second level of negative pressure at the wound bed corresponding to a physiotherapy mode (e.g., <NUM> mmHg), where the second level is closer to ambient air pressure than the first level.

The therapy unit <NUM> also includes an instillation pump <NUM>. The instillation pump <NUM> is configured to selectively provide instillation fluid from the instillation fluid source <NUM> to the dressing <NUM>. The instillation pump <NUM> is operable to control the timing and amount (volume) of instillation fluid provided to the dressing <NUM>. The instillation pump <NUM> may be controlled in coordination with the negative pressure pump <NUM> 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 <NUM>.

The therapy unit <NUM> is also shown to include an input/output device <NUM>. The input/output device <NUM> is configured to provide information relating to the operation of the NPWTi system <NUM> to a user and to receive user input from the user. The input/output device <NUM> may display status information relating to the NPWTi system <NUM>, for example including measurements obtained from the sensor(s) <NUM> of the dressing <NUM> or the sensor(s) <NUM> of the therapy unit <NUM>. The input/output device <NUM> may allow a user to input various preferences, settings, commands, etc. that may be used in controlling the negative pressure pump <NUM> and the instillation pump <NUM> as described in detail below. The input/output device <NUM> 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.

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

The control circuit <NUM> is configured to control the operation of the therapy unit <NUM>, including by controlling the negative pressure pump <NUM>, the instillation pump <NUM>, and the input/output device <NUM>. The control circuit <NUM> may receive measurements from the sensor(s) <NUM> and the sensor(s) <NUM> and/or user input from the input/output device <NUM> and use the measurements and/or the user input to generate control signals for the instillation pump <NUM> and/or the negative pressure pump <NUM>. For example, the control circuit <NUM> may control the negative pressure pump <NUM> and the instillation pump <NUM> 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>, the control circuit <NUM> is configured to automatically initiate a wound therapy mode in response to strain measurements from the sensor(s) <NUM> by controlling the negative pressure pump <NUM> to reduce the negative pressure at the dressing <NUM>, thereby allowing increased mobility, flexion, articulation, etc. of the hand treated by the dressing <NUM>.

Referring now to <FIG>, various views of a first embodiment not in accordance with the claimed invention of the dressing <NUM> is shown. <FIG> shows a top view of the dressing <NUM> and <FIG> show various cross-sectional views of the dressing <NUM>.

In <FIG>, the dressing <NUM> is shown to include a first manifold layer <NUM>, a second manifold layer <NUM>, a first barrier layer <NUM> that is adjacent to (e.g., abuts) the first manifold layer <NUM>, and a second barrier layer <NUM> abuts the second manifold layer <NUM>. The first manifold layer <NUM> and the second manifold layer <NUM> are positioned between the first barrier layer <NUM> and the second barrier layer <NUM>. In some embodiments, the first manifold layer <NUM> is coupled to the first barrier layer <NUM> by an adhesive and/or the second manifold layer <NUM> is coupled to the second barrier layer <NUM> by an adhesive.

The dressing <NUM> is also shown to includes a first fenestrated film layer <NUM> that abuts the first manifold layer <NUM> with and a second fenestrated film layer <NUM> that abuts the second manifold layer <NUM>. The first manifold layer <NUM> is positioned between the first fenestrated film layer <NUM> and the first barrier layer <NUM>, and the second manifold layer <NUM> is positioned between the second fenestrated film layer <NUM> and the second barrier layer <NUM>. In some embodiments, the first fenestrated film layer <NUM> is coupled to the first manifold layer <NUM> by an adhesive and/or the second fenestrated film layer <NUM> is coupled to the second manifold layer <NUM> by an adhesive. In preferred embodiments. The first fenestrated film layer <NUM> is configured to be easily separated from the second fenestrated film layer <NUM>. That is, the first fenestrated film layer <NUM> and the second fenestrated film layer <NUM> are configured to not adhere to one another.

As illustrated in <FIG>, the first manifold layer <NUM>, the second manifold layer <NUM>, the first barrier layer <NUM>, the second barrier layer <NUM>, the first fenestrated film layer <NUM>, and the second fenestrated film layer <NUM> are hand-shaped. That is, each of the layers <NUM>-<NUM> includes a central region <NUM> and five peninsular projections <NUM> that extend from the central region <NUM> in the shape of a hand. Each of the five peninsular projections <NUM> corresponds to one finger or thumb of a patient. The dressing <NUM> may be made available in various sizes corresponding to different hand sizes (i.e., different dimensions of the central region <NUM> and the peninsular projections <NUM> of the layers <NUM>-<NUM>). For example, the dressing <NUM> 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.

The first barrier layer <NUM> is coupled to the second barrier layer <NUM> along a hand portion of a perimeter of the dressing <NUM> and separated from the second barrier layer <NUM> along a wrist portion <NUM> of the perimeter of the dressing <NUM>. The first barrier layer <NUM> is not coupled to the second barrier layer <NUM> along the wrist portion <NUM> of the perimeter of the dressing <NUM>, which creates an opening that allows a patient's hand to be inserted into the dressing <NUM>. In other words, the dressing <NUM> is formed as a glove. The dressing <NUM> is thereby configured to receive a patient's hand between the first fenestrated film layer <NUM> and the second fenestrated film layer <NUM>.

In the example shown, the first barrier layer <NUM> is coupled to the second barrier layer <NUM> along edges of the peninsular regions <NUM> and the central region <NUM> by film welds <NUM>, and along a portion of the perimeter of the central region by anchor welds <NUM>. <FIG> shows a cross-section view of the dressing <NUM> including film welds <NUM>. The film welds <NUM> couple the first barrier layer <NUM> to the second barrier layer <NUM> and substantially prevent air from passing between the first barrier layer <NUM> and the second barrier layer <NUM> at the film welds. For example, the first barrier layer <NUM> may be thermally bonded to the second barrier layer <NUM> at the film welds <NUM>.

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

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

The barrier layers <NUM>, <NUM> are configured to substantially prevent airflow therethrough. The barrier layers <NUM>, <NUM> may include a polyurethane drape material, for example a drape material as used in a V. ® Drape by Acelity. As mentioned above, the barrier layers <NUM>, <NUM> are sealed with a substantially-airtight seal by film welds <NUM>. Accordingly, when the adhesive cuff <NUM> is sealed around the wrist of a patient and the barrier layers <NUM>, <NUM>, a substantially airtight volume is created within the dressing <NUM>, i.e., between the barrier layers <NUM>, <NUM> and the patient's hand. The barrier layers <NUM>, <NUM> may each have a thickness in a range between approximately <NUM> and <NUM> microns.

As shown in <FIG>, the first barrier layer <NUM> includes knuckle flexion points <NUM> arranged at positions that correspond to knuckles/joints within a typical hand that may be inserted into the dressing <NUM>. In the example shown, each peninsular portion <NUM> corresponding to a finger includes three knuckle flexion points <NUM>, while the peninsular portion <NUM> corresponding to a thumb includes two knuckle flexion points. <FIG> shows cross sectional views of a knuckle flexion point <NUM>, includes a first view <NUM> of the knuckle flexion point <NUM> in an unflexed state and a second view <NUM> of the knuckle flexion point <NUM>. As illustrated by <FIG>, each knuckle flexion point <NUM> includes a series of folds (e.g., three folds) which, in the unflexed state, draw the barrier layer <NUM> away from the manifold layer <NUM>. In the flexed state, the series of folds are extended (unfolded) to facilitate curvature (bending) of the dressing <NUM> at the knuckle flexion point <NUM> by increasing an effective length of the barrier layer <NUM>. Accordingly, the knuckle flexion points <NUM> are configured to facilitate articulation, movement, etc. of a patient's fingers confined in the dressing <NUM>. The fenestrated film layers <NUM>, <NUM> and the manifolding film layers <NUM>, <NUM> may be configured to resiliently stretch and/or flex to accommodate articulation, movement, etc. of a hand in the dressing <NUM> as shown in <FIG>.

The fenestrated film layers <NUM>, <NUM> are made of a non-adherent film and are configured to provide a non-adherent interface between the dressing <NUM> and a hand of a patient, including a wound bed located on the hand. The fenestrated film layers <NUM>, <NUM> are also configured to prevent ingrowth of skin to the dressing (e.g., healing into the manifold layers <NUM>, <NUM>). The fenestrated film layer <NUM>, <NUM> thereby facilitate easy insertion of a hand into the dressing <NUM> and removal of the hand from the dressing <NUM>. Additionally, the fenestrated film layers <NUM>, <NUM> 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 <NUM>, <NUM>. The fenestrated film layers <NUM> may each have a thickness of approximately <NUM> microns.

The manifold layers <NUM>, <NUM> 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 <NUM>, <NUM> are made of an open-cell foam marketed as GRANUFOAM™ by ACELITY™. The manifold layers <NUM>, <NUM> may each have a thickness in a range between approximately <NUM> and <NUM>. Accordingly, the manifold layers <NUM>, <NUM> may be thinner than in conventional bulky dressings. The reduced thickness of the manifold layers <NUM>, <NUM> facilitates flexion of the dressing <NUM> to allow for physiotherapy for the hand in the dressing <NUM> in a way not previously achieved.

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

The dressing <NUM> is configured to be coupled to a vacuum (negative pressure) tube <NUM> and, in some embodiments, an instillation tube <NUM>. For example, a hole may be cut in the first barrier layer <NUM> (e.g., with a diameter in a range between approximately <NUM>-<NUM>) and a connection pad may be coupled to the barrier layer <NUM> over the hole. The connection pad is coupled to the vacuum tube <NUM> and/or instillation tube <NUM>. In some embodiments, multiple holes and/or connection pads are used. For example, the connection pad may be a SENSAT. ™ connection pad marketed by ACELITY™.

The manifold layers <NUM>, <NUM> can thereby be put in fluid communication with the vacuum tube <NUM> and/or instillation tube <NUM>. As described above with reference to <FIG>, the negative pressure pump <NUM> can be controlled to remove air from the manifold layers <NUM>, <NUM> to establish a negative pressure at the manifold layers <NUM>, <NUM>. The negative pressure at the manifold layers <NUM>, <NUM> is communicated to the hand/wound via the fenestrations in the fenestrated film layers <NUM>, <NUM>. Instillation fluid may also be provided to the wound via the manifold layers <NUM>, <NUM> and the fenestrated film layers <NUM>. Wound exudate, instillation fluid, other debris, etc. may also be removed from the wound and manifold layers via the vacuum tube <NUM> as described above with reference to <FIG>. The dressing <NUM> thereby facilitates treatment of a hand wound using NPWTi.

Still referring to <FIG>, the dressing <NUM> is also shown to include one or more sensor(s) <NUM>. positioned on the first barrier layer <NUM>. 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 <NUM> to measure humidity and moisture in the first manifold layer <NUM>. 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 <NUM>. The strain sensor <NUM> is positioned on or in the first barrier layer <NUM> and extends along a length of the dressing from proximate the wrist portion <NUM> to a tip of one of the peninsular regions <NUM> (e.g., corresponding to a middle finger). The strain sensor <NUM> is configured to measure (e.g., generate an electrical signal indicative of) a strain on the dressing <NUM> (i.e., on the strain sensor <NUM>), which may correspond to a curvature of the dressing <NUM> and/or a force applied by the hand inside the dressing <NUM>. For example, a strain measured by the strain sensor <NUM> 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 <NUM>. The strain may decrease when the patient moves the hand in the dressing <NUM> to an open or neutral pose. The one or more sensors <NUM> 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 <NUM> of the therapy unit <NUM>.

Referring now to <FIG>, a second embodiment also not in accordance with the claimed invention of the dressing <NUM> is shown, according to an exemplary embodiment. In <FIG>, the non-adhesive fenestrated film layers <NUM>, <NUM> are omitted from the dressing <NUM>, such that the dressing <NUM> is formed as a glove including the barrier layers <NUM>, <NUM> and the manifold layers <NUM>, <NUM> arranged as described above. A wound-dressing interface <NUM> 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 <NUM> formed from the barrier layers <NUM>, <NUM> and the manifold layers <NUM>, <NUM>). The wound-dressing interface <NUM> is formed as a single piece (sheet) as shown in <FIG>, 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 <NUM> is folded over a patient's hand.

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

The wound-dressing interface <NUM> 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 <NUM> such that the patient interface layer <NUM> faces inwards (i.e., towards the hand) and the foam interface layer <NUM> faces outwards (i.e., away from the hand). The hand and the wound-dressing interface <NUM> can then be inserted into the glove portion of the dressing <NUM>, i.e., the barrier layers <NUM>, <NUM> and the manifold layers <NUM>, <NUM> arranged as described above (and as shown in <FIG> and <FIG>). With the hand enclosed in the wound-dressing interface <NUM>, the wound-dressing interface <NUM> prevents direct contact between the hand and the manifold layers <NUM>, <NUM> while allowing air and fluid to pass through fenestrations in the wound-dressing interface <NUM>. The adhesive cuff <NUM> can then be applied around the patient's wrist to seal the dressing <NUM> around the hand as described above. To further prepare the dressing <NUM> for NPWTi, a hole can be cut in a barrier layer <NUM>, <NUM> and a connection pad coupled to the barrier layer <NUM>, <NUM> over the hole to place a vacuum tube <NUM> and/or an instillation tube <NUM> in fluid communication with the manifold layers <NUM>, <NUM>. The therapy unit <NUM> can then be operated as described above to establish negative pressure at the hand and/or provide instillation fluid to the hand.

The embodiments of <FIG> show glove-shaped dressings, i.e., with individually-differentiated fingers (e.g., as formed by peninsular projections <NUM>). Other embodiments of the dressing <NUM> 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 <FIG>. 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.

Referring now to <FIG>, a process <NUM> of providing a physiotherapy mode with the NPWTi system <NUM> of <FIG> and the hand dressing <NUM> of <FIG> is shown, according to an exemplary embodiment not in accordance with the invention. Process <NUM> provides a physiotherapy mode that allows movement, articulation, bending, etc. of a hand in the dressing <NUM> during NPWTi treatment. Accordingly, execution of process <NUM> facilitates a patient in redeveloping strength, neuromuscular activity, coordination, etc. in the hand while the dressing <NUM> is applied to the hand. Additionally, movement of the hand as provided for by process <NUM> 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 <NUM> can be executed by the control circuit <NUM> of the therapy unit <NUM>.

At step <NUM>, the negative pressure pump <NUM> is operated to establish a first level of negative pressure at the glove-shaped dressing <NUM>. The first level of negative pressure may correspond to a preferred level for negative pressure wound therapy, for example in the range of approximately <NUM> mmHg to <NUM> 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 <NUM> increases the rigidity of the dressing <NUM> such that dressing <NUM> substantially restricts (limits, prevents, etc.) articulation of the hand.

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

At step <NUM>, 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 <NUM>. In the measurement does not exceed the threshold measurement, pump <NUM> continues to be controlled to provide the first level of negative pressure at the dressing <NUM> while more measurements of the strain are received at the control circuit <NUM> over time.

If a determination is made that the measurement of the strain exceeds the threshold strain value, a physiotherapy mode is initiated at step <NUM>. At step <NUM>, the pump <NUM> is controlled (e.g., by the control circuit <NUM>) 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 <NUM> mmHg). At the second level of negative pressure, the rigidity of the dressing <NUM> is lower than at the first level of negative pressure. Accordingly, at the second level of negative pressure, the dressing <NUM> and the NPWIT system <NUM> allows the patient to at least partially bend, articulate, move, etc. the fingers and hand in the dressing <NUM>. 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 <NUM>.

At step <NUM>, additional measurements of the strain are received from the strain sensor <NUM>. As the patient continues to articulate the hand in the dressing <NUM>, the strain will stay above the threshold strain value and/or repeatedly exceed the threshold strain value. At step <NUM>, 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 <NUM>. If the strain has not fallen below the threshold strain value for at least the threshold duration of time, the pump <NUM> continues to be controlled to maintain the second level of negative pressure at the dressing.

If the strain has fallen below the threshold strain value for at least the threshold duration of time, the pump <NUM> is controlled to reestablish the first level of negative pressure at the dressing at step <NUM>, i.e., to reestablish an optimal NPWTi regime and exit the physiotherapy mode. The process may then return to step <NUM> 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 <NUM> over time. With the advantages described above, the dressing <NUM> may be well-suited for long-term application to the hand (e.g., seven days or longer).

Several variations on the process <NUM> 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 <NUM> commanding a start or end to the physiotherapy mode. As another example, the control circuit <NUM> may prevent execution of the process <NUM> (e.g., prevent initiation of physiotherapy mode) during an instillation cycle (e.g., while instillation fluid is being supplied to the dressing <NUM>). 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.

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 <NUM> can therefore be tailored for use in treating wounds in many anatomical locations.

The dressing <NUM> and NPWTi system <NUM> described above provide various advantages over existing dressings and wound therapy systems. The dressing <NUM> 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 <NUM> and NPWTi system <NUM> also allow for effective positioning of the dressing <NUM> 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 <NUM> and NPWTi system <NUM>, in the embodiments shown, are suitable for providing negative pressure and instillation therapy for up to at least seven days. The dressing <NUM> may reduce the use of foam relative to existing dressings, thereby making the dressing <NUM> smaller and less cumbersome for the patient. The dressing <NUM> and the NPWTi system <NUM>, in the embodiments shown, also provide for an automatic physiotherapy mode that facilitates rehabilitation and reduces the risk of contractures. Additionally, the dressing <NUM> 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 <NUM> and NPWTi system <NUM> disclosed herein provide many advantages over existing systems that can improve outcomes for patients while also improving the overall treatment experience.

Referring now to <FIG>, another embodiment of the dressing <NUM> is shown, according to exemplary embodiments. <FIG> show various perspective views of the dressing <NUM>. <FIG> shows a cross-sectional view of the dressing <NUM>. <FIG> illustrates an advantageous behavior of the dressing <NUM> when air is removed from the dressing <NUM>. The dressing <NUM> as in <FIG> may include some or all of the various features and advantages of the dressing <NUM> in the embodiments described above, with some differences as described in detail below. Advantageously, as shown in <FIG>, the dressing <NUM> includes transparent or translucent portions such that a patient or caregiver can visually assess a wound without removing the dressing <NUM> from the patient's hand.

As shown in <FIG>, the manifold layers <NUM>, <NUM> are formed as multiple felted foam strips <NUM> which extend from a felted foam pad <NUM>. Each felted foam strip extends from the central region <NUM> of the dressing to one of the multiple peninsular projections <NUM>. In other words, each "finger" (including the "thumb") of the dressing <NUM> has a corresponding felted foam strip <NUM> aligned therewith. In the example shown, both a first side <NUM> of the dressing <NUM> (corresponding to a back of the hand) and a second side <NUM> of the dressing <NUM> (corresponding to the palm of the hand) include felted foam strips <NUM>. Accordingly, in this example, two felted foam strips <NUM> are aligned with each of the peninsular projections <NUM> (i.e., one felted foam strip <NUM> on the first side <NUM> and one felted foam strip <NUM> on the second side <NUM>). It should be understood that various arrangements, numbers, patterns, webs, lattices, etc. of felted foam strips <NUM> are possible in various embodiments.

In the example of <FIG>, the felted foam pad <NUM> includes a wrist strap <NUM> and a connection surface <NUM>. The wrist strap <NUM> (e.g., felted foam cuff) is located at a wrist region of the dressing <NUM> and connects the felted foam strips <NUM> of the first side <NUM> with the felted foam strips <NUM> of the second side <NUM>, thereby allowing air and fluid to flow between the felted foam strips <NUM> of the first side <NUM> and the felted foam strips <NUM> of the second side (e.g., to facilitate communication of negative pressure between the first side <NUM> and the second side <NUM>).

The connection surface <NUM> provides an area of felted foam having a sufficient surface area to allow connection of the dressing <NUM> to the tube <NUM> in fluid communication with the manifolding layer <NUM> (i.e., with the wrist strap <NUM> and the felted foam strips <NUM>). In the example shown, the felted foam strips <NUM> and the wrist strap <NUM> may be narrow (e.g., having a width less than a diameter of a connection pad <NUM> which couples the dressing <NUM> to the vacuum tube <NUM> and, in some embodiments, to the instillation tube <NUM>. The connection surface <NUM> provides a larger surface area (e.g., having a diameter equal to or larger than the diameter of the connection pad <NUM>; 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 <NUM> to be placed in fluid communication with the manifolding layer <NUM>. In the example shown in <FIG>, the connection surface <NUM> of the felted foam pad <NUM> is located along a forearm region of the dressing <NUM>, such that the connection pad <NUM> is positioned at a non-articulating anatomical feature when applied to a patient. The connection surface <NUM> thereby provides a convenient, comfortable, and effective position at which the connection pad <NUM> can be coupled to the dressing <NUM>.

As shown in <FIG> and consistent with the embodiment of <FIG> described above, the dressing <NUM> includes as a first manifold layer <NUM> (shown as a felted foam strip <NUM>), a second manifold layer <NUM> (also shown as a felted foam strip <NUM>), a first barrier film layer <NUM>, a second barrier film layer <NUM>, a first fenestrated film layer (wound contact layer) <NUM>, and a second fenestrated film layer (wound contact layer) <NUM>. The first manifold layer <NUM> is positioned between the first fenestrated film layer <NUM> and the first barrier layer <NUM>, and the second manifold layer <NUM> is positioned between the second fenestrated film layer <NUM> and the second barrier layer <NUM>. The first manifold layer <NUM>, the first fenestrated film layer <NUM>, and the first barrier film layer <NUM> form a first side <NUM> of the dressing <NUM>. The second manifold layer <NUM>, the second fenestrated film layer <NUM>, and the second barrier layer <NUM> form a second side of the dressing <NUM>. In some embodiments, the first side <NUM> and/or the second side <NUM> 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 <NUM>.

In the example of <FIG>, the first manifold layer <NUM> and second manifold layer <NUM> are formed as felted foam strips <NUM> that occupy only a portion (i.e., less than an entirety) of the surface area of the barrier film layers <NUM>, <NUM> and only a portion (i.e., less than an entirety) of the surface area of the fenestrated film layers <NUM>, <NUM>. The felted foam strips <NUM> 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 <NUM> unoccupied by the felted foam strips <NUM>, the first barrier film layer <NUM> is adjacent to (e.g., abutting) the first fenestrated film layer <NUM> and the second barrier film layer <NUM> is adjacent to the second fenestrated film layer <NUM>.

In some embodiments, the barrier film layers <NUM>, <NUM> and the fenestrated film layers <NUM> are transparent or translucent. In such embodiments and in regions unoccupied by the felted foam strips <NUM>, the dressing <NUM> can be transparent or translucent. Accordingly, in the embodiments of <FIG>, the dressing <NUM> is configured to allow a patient or caregiver to visually assess (see, optically inspect, etc.) a wound through the dressing <NUM> without removal or modification of the dressing <NUM>. The dressing <NUM> thereby facilitates a caregiver or patient in monitoring wound healing and, in some cases, making adjustments to wound therapy based on such monitoring.

The first side <NUM> and the second side <NUM> may be coupled together by welds <NUM> and/or <NUM> around a perimeter of the dressing <NUM> with the exception of an opening at a wrist portion <NUM> of the perimeter of the dressing <NUM> (e.g., as described above with reference to <FIG>). In the examples of <FIG>, spot welds <NUM> may also be included and distributed between and around the felted foam strips <NUM>. At the first side <NUM>, the first barrier film layer <NUM> is coupled (e.g., welded, adhered) to the first fenestrated film layer <NUM>. At the second side <NUM>, the second barrier film layer <NUM> is coupled to the second fenestrated film layer <NUM>. The spot welds <NUM> may be placed to partially constrain movement of the of the felted foam strips <NUM>. For example, spot welds <NUM> may be placed slightly apart from the felted foam strips <NUM> such that the felted foam strips <NUM> are allowed to move, bend, translate, slide, etc. within a limited range of positions relative to the barrier film layer <NUM>/<NUM> and the fenestrated film layer <NUM>/<NUM>. In some cases, the spot welds <NUM> ensure that the felted foam strips <NUM> remain substantially aligned with the peninsular (finger, thumb) regions <NUM> while allowing for some movement and repositioning which facilitates the dressing <NUM> in conforming to a particular patient's hand, provides flexibility to the dressing <NUM>, and facilitates articulation of the patient's hand while the dressing <NUM> is applied to the hand. In other embodiments, an adhesive can be included to couplet the felted foam strips <NUM> to the barrier film layer <NUM>/<NUM> and/or the fenestrated film layer <NUM>/<NUM>.

<FIG> illustrates application and use of the dressing <NUM> of <FIG> in a two-frame storyboard depiction. As illustrated in the first frame <NUM>, the dressing <NUM> is placed onto a patient's hand and the adhesive cuff <NUM> is applied to seal the dressing <NUM> around the patient's wrist or forearm. In various embodiments, the dressing <NUM> 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 <NUM> may be sized slightly larger than the hand to facilitate insertion of the hand into the dressing <NUM>. When the adhesive cuff <NUM> is sealed around the opening in the dressing <NUM> and the patient's wrist or forearm, a substantially-airtight internal volume is created between the dressing <NUM> and the hand.

To transition from the first frame <NUM> to the second frame <NUM>, the negative pressure pump <NUM> is operated to remove air and/or other fluids or debris from the dressing <NUM> via the tube <NUM>, the connection pad <NUM>, the felted foam pad <NUM>, and the felted foam strips <NUM> to establish a negative pressure within the dressing <NUM> and at the hand (e.g., at a wound). Operating the negative pressure pump <NUM> results in a reduction in volume of the dressing <NUM> as the dressing <NUM> is pulled inwards towards the hand by the pressure differential across the barrier film layers <NUM>, <NUM>.

As illustrated in the second frame <NUM>, the reduction in volume of the dressing <NUM> in response to operation of the negative pressure pump <NUM> results in the formation of wrinkles (creases, folds, etc.) in the barrier film layers <NUM>, <NUM> and the fenestrated film layers <NUM>, <NUM>. 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 film layers <NUM>, <NUM> and the fenestrated film layers <NUM>, <NUM>. Furthermore, at least a portion of the wrinkles are in fluid and/or pneumatic communication with the felted film strips <NUM>. Accordingly, air and fluid can flow between the felted film strips <NUM> and regions of the hand not directly aligned with the felted foam strips <NUM>.

Therefore, although the felted foam strips <NUM> cover only a portion of the surface area of the dressing <NUM> and the hand treated thereby, the wrinkles formed by operation negative pressure pump <NUM> can provide air and fluid manifolding to a much larger portion of the surface area of the dressing <NUM> and the hand (e.g., to the substantially the entire hand). The dressing <NUM> 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 <NUM>, a patient or caregiver can visually inspect a wound without removing the dressing <NUM>, including while negative pressure is established at the hand.

In some embodiments, one or more thermo-chromic indicators are positioned on the fenestrated film layers <NUM>, <NUM>, for example on the inner (i.e., hand-facing) surface or outer (i.e., non-hand-facing) surface of the fenestrated film layers <NUM>, <NUM>. 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 <NUM> of <FIG> is translucent or transparent in various regions, such indicators may be visible through the dressing <NUM>, 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 burns. Multiple indicators can be used to provide temperature information at multiple locations of the dressing <NUM>. In some embodiments, pH-chromic indicators configured to change color with changes in pH may be included with the dressing <NUM> and opinionated like the thermo-chromic indicators to provide information relating to the pH of the hand at various areas of the hand.

Various other embodiments of the dressing <NUM> are also possible. For example, in some embodiments the felted foam strips <NUM> are non-felted. That is, the foam strips <NUM> 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 <NUM> are replaced by non-foam thermoformed pathways, for example tubes or other pathways formed on or coupled to the barrier film 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 <NUM> can be omitted.

Claim 1:
A dressing (<NUM>) for negative pressure wound therapy, comprising:
a barrier film layer (<NUM>);
a wound contact layer (<NUM>) coupled to the barrier film layer (<NUM>); and
a plurality of felted foam strips (<NUM>) positioned between the barrier film layer (<NUM>) and the wound contact layer (<NUM>), each strip providing a manifolding pathway;
wherein the barrier film layer (<NUM>) and the wound contact layer (<NUM>) comprise a central region (<NUM>) and a plurality of peninsular projections (<NUM>) extending therefrom in the shape of a hand; and
wherein the plurality of felted foam strips (<NUM>) occupy only portion of the surface area of the barrier film layer (<NUM>) and only a portion of the surface area of the wound contact layer (<NUM>).