Integrated Negative Pressure Wound Therapy Device

Abstract

Disclosed herein are systems and methods for safely operating a wound treatment device having electronic components integrated onto or within a wound dressing. In some embodiments, the electronic components include a power source, an isolation circuit, a controller, a capacitor, and a negative pressure source. The isolation circuit provides multiple activation states, with at least one state preventing application of power to other electronic components capable of storing electrical energy, thereby safely operating the device. For example, sterilization of the device can be safely performed. [Selected figure] Figure 8B

Description

[Technical field]

[0001] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments described herein relate to devices, systems, and methods for treating wounds using dressings in combination with negative pressure wound therapy, for example. [Background technology]

[0002] 2. Description of Related Art Treatment of open or chronic wounds that are too large to close naturally or otherwise heal by application of negative pressure to the wound site is well known in the art. Negative pressure wound therapy (NPWT) systems currently known in the art involve placing a fluid-impermeable or semi-permeable covering over the wound, using various means to seal the covering against the patient's tissue surrounding the wound, and connecting a negative pressure source (such as a vacuum pump) to the covering in such a manner that a negative pressure is created and maintained beneath the covering. Such negative pressure is believed to promote wound healing by promoting the formation of granulation tissue at the wound site and assisting the body's normal inflammatory processes while simultaneously removing excess fluids that may contain harmful cytokines and / or bacteria. However, further refinements of NPWT are needed to fully realize the therapeutic benefits.

[0003] Many different types of wound dressings are known that are useful in NPWT systems. The various types of wound dressings include various types of materials and layers, such as gauze, pads, foam pads, or multi-layer wound dressings. One example of a multi-layer wound dressing is the PICO dressing from Smith & Nephew, which includes a superabsorbent layer under a backing layer, resulting in a canister-less system for treating wounds by NPWT. The wound dressing may be sealed to a suction port that connects to a line of tubing, which can be used to draw fluid from the dressing and / or transfer negative pressure from a pump to the wound dressing.

[0004] Conventional dressings using negative pressure, such as those described above, have included a negative pressure source located remotely from the wound dressing. The negative pressure source located remotely from the wound dressing must be held by or attached to a user or other pump support mechanism. Additionally, tubing or connectors are required to connect the remote negative pressure source to the wound dressing. Remote pumps and tubing can be cumbersome and difficult to hide or attach in the patient's clothing. Depending on the location of the wound dressing, it can be difficult to comfortably and conveniently locate the remote pump and tubing. During operation, wound exudate can seep into the dressing, and moisture from the wound makes it difficult to get electronic components into the dressing. Summary of the Invention

[0005] In some embodiments, a negative pressure wound therapy system includes a wound dressing configured to be placed over a wound of a patient, a negative pressure source disposed on or within the dressing and configured to provide negative pressure to the wound, and an electronic circuit disposed on or within the dressing. The electronic circuit may include a controller configured to operate the negative pressure source, a power source configured to provide power to the electronic circuit, and an isolation circuit in electrical communication with the power source and the controller. The isolation circuit may be configured to operate in a first state that prevents the isolation circuit from applying power to the controller, and a second state that allows the isolation circuit to apply power to the controller. The isolation circuit may include an activation switch configured to be activated to cause the isolation circuit to operate in the second state.

[0006] The system described in the preceding paragraph may include one or more of the following features: The activation switch is activated by a tab configured to be removed by a user, activation of the activation switch may operate the isolation circuit in a second state. The activation switch may be configured to remain in an activated state after removal of the tab. The tab may include a conductive material configured to be applied to the activation switch to activate the activation switch. The conductive material may include silver ink deposited on a region of the tab, the region may be configured to contact the activation switch during activation. The region may be configured to make an electrical contact. The activation switch may be a button. The electronic circuit may include at least one capacitor configured to store energy provided by the power source and configured to provide the stored energy to the negative pressure source. The isolation circuit in the first state of operation may be further configured to prevent charging of the at least one capacitor. The electronic circuit may further include an operation switch configured to activate and pause provision of negative pressure by the negative pressure source. The isolation circuit may include a latch circuit. The power source may be non-removable. The negative pressure source may be a micropump.

[0007] The system of any of the preceding paragraphs may include one or more of the following features: The electronic circuit may be configured to inhibit activation of the negative pressure source to provide negative pressure when the isolation circuit is in a first state and the operating switch is activated. The latch circuit may be configured to maintain the isolation circuit in a second state in response to an initial activation of the activation switch. The latch circuit may be configured to maintain the isolation circuit in a second state in response to a deactivation of the track switch after the initial activation. The electronic circuit may be configured to inhibit activation of the negative pressure source to provide negative pressure when the isolation circuit is in the first state. The system may include an indicator configured to provide at least one of an indication that the activation switch has not been activated or an indication that the activation switch has been activated. The controller may include a boost converter configured to power the negative pressure source, and the system may include a primary controller configured to be powered by the power source when the isolation circuit is in the first or second state. The system may include at least one energy storage element and may be configured to store energy provided by the boost converter and power the negative pressure source with the stored energy.

[0008] In some embodiments, a method of operating a negative pressure wound therapy device including a wound dressing, a negative pressure source disposed on or within the dressing, and an electronic circuit disposed on or within the dressing and configured to operate the negative pressure source includes activating an activation switch configured to operate the electronic circuit in a first state in which power is applied to a controller of the electronic circuit, while the electronic circuit operated in a second state in which power was not applied to the controller and the device was sterilized with ethylene oxide (EtO), positioning the wound dressing over a wound of a patient, and activating the negative pressure source to provide negative pressure to the wound.

[0009] The method described in the above paragraph may include one or more of the following features: Activating the activation switch may be performed by removing a tab. The activation switch may be a button. Activating the negative pressure source may include activating an operating switch configured to activate and deactivate the source of negative pressure.

[0010] In some embodiments, a method of operating a negative pressure wound therapy device including a wound dressing, a negative pressure source disposed on or within the dressing, and an electronic circuit disposed on or within the dressing and configured to operate the negative pressure source includes activating an activation switch configured to operate the electronic circuit in a first state in which power is applied to a controller of the electronic circuit, while the electronic circuit operated in a second state in which power was not applied to the controller and the device was sterilized with ethylene oxide (EtO), and activating the negative pressure source to provide negative pressure to the wound dressing.

[0011] The method of any of the preceding paragraphs can include one or more of the following features: Activating the activation switch can be performed by removing a tab. The activation switch can be a button and activating the activation switch can be performed by pressing the button. Activating the source of negative pressure can include activating an operation switch configured to start and stop the source of negative pressure.

[0012] In some embodiments, a method of operating a negative pressure wound therapy device including a wound dressing, a negative pressure source disposed on or within the dressing, and an electronic circuit configured to operate the negative pressure source includes maintaining an isolation circuit of the electronic circuit in an inactive state while power is not provided to an energy storage component of the electronic circuit configured to provide power to the negative pressure source, where in response to activation of an activation switch of the electronic circuit, the device is sterile when the isolation circuit is in the inactive state, transitioning the isolation circuit to an active state while power is provided to the energy storage component, and activating the negative pressure source when the isolation circuit is in the second state. The device may be sterilized with ethylene oxide (Eto).

[0013] The method of any of the above paragraphs may include one or more of the following features: The method may include maintaining the isolation circuit in an activated state in response to an initial activation of the activation switch. Activating the activation switch may include at least one of pulling a tab, pressing a button, or connecting a secondary power source. Activating the negative pressure source may include activating the negative pressure source in response to activation of the operation switch. The method may include deactivating the negative pressure source in response to deactivation of the operation switch. The method may include not activating the negative pressure source in response to activation of the operation switch when the isolation circuit is in a deactivated state. The method may include indicating at least one of that the activation switch has not been activated or that the activation switch has been activated. The energy storage component may be a capacitor.

[0014] In some embodiments, the negative pressure wound therapy device includes a wound dressing, a negative pressure source disposed on or within the dressing, and an electronic circuit disposed on or within the wound dressing and configured to operate the negative pressure source. The activation circuit can include an isolation circuit configured to be maintained in an inactive state in which no power is provided to an energy storage component of the electronic circuit configured to provide power to the negative pressure source, and the device is sterilized when the isolation circuit is in the inactive state. The isolation circuit can be further configured to transition to an active state in which power is provided to the energy storage component in response to activation of an activation switch of the electronic circuit.

[0015] The device described in any of the above paragraphs may include one or more of the following features: The device may be sterilized with ethylene oxide (Eto). The isolation circuit may be configured to remain in an activated state in response to an initial activation of the activation switch. Activation of the activation switch may include at least one of pulling a tab, pressing a button, or connecting a secondary power source. Activation of the negative pressure source may be effected (e.g., by the electronic circuit) in response to activation of the operation switch. Deactivation of the negative pressure source may be effected (e.g., by the electronic circuit) in response to deactivation of the operation switch. The electronic circuit may be configured to not activate the negative pressure source in response to activation of the operation switch when the isolation circuit is in a deactivated state. The electronic circuit may be configured to provide an indication of at least one of that the activation switch has not been activated or that the activation switch has been activated. The energy storage component may include a capacitor.

[0016] Any of the features, components, or details of any of the arrangements or embodiments disclosed in this application, including but not limited to any of the pump embodiments disclosed below, and any of the negative pressure wound therapy embodiments, may be combined with any of the other features, components, or details of any of the arrangements or embodiments disclosed herein to form new arrangements and embodiments. [Brief description of the drawings]

[0017] The features and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0018] [Figure 1A] FIG. 1A illustrates a wound dressing in which a negative pressure source and / or other electronic components are integrated within the wound dressing. [Figure 1B] FIG. 1B illustrates a wound dressing in which a negative pressure source and / or other electronic components are integrated within the wound dressing. [Figure 1C] FIG. 1C illustrates a wound dressing in which a negative pressure source and / or other electronic components are incorporated within the wound dressing. [Figure 2A] FIG. 2A illustrates an embodiment of an electronic unit integrated into a wound dressing. [Figure 2B] FIG. 2B illustrates an embodiment of an electronic unit integrated into a wound dressing. [Figure 3A] FIG. 3A illustrates one embodiment of a wound dressing layer that incorporates electronic components within the wound dressing. [Figure 3B] FIG. 3B illustrates a cross-sectional layout of material layers of a wound dressing incorporating an electronic assembly within the dressing. [Figure 3C] FIG. 3C illustrates a top view of an embodiment of a wound dressing layer incorporating an electronic assembly within the dressing. [Figure 4] FIG. 4 illustrates a block diagram of various physical and electrical components of a negative pressure wound treatment system according to some embodiments. [Diagram 5] FIG. 5 illustrates a block diagram of a negative pressure wound therapy system configured to isolate electronics from the power source according to some embodiments. [Figure 6A] FIG. 6A illustrates a circuit diagram of the electronic circuitry of a negative pressure wound treatment system, according to some embodiments. [Figure 6B] FIG. 6B illustrates a circuit diagram of the electronic circuitry of a negative pressure wound treatment system, according to some embodiments. [Figure 7]FIG. 7 illustrates a back view of a printed circuit board (PCB) configured to implement a two-stage start-up according to some embodiments. [Figure 8A] 8A illustrates a front view of a two-stage activation PCB before and after the pull tab has been pulled, respectively, according to some embodiments. [Figure 8B] 8A and 8B illustrate front views of the two-stage activation PCB before and after the pull tab is pulled, respectively, according to some embodiments. [Figure 9A] FIG. 9A illustrates various designs for the pull tab according to some embodiments. [Figure 9B] FIG. 9B illustrates various designs for the pull tab according to some embodiments. [Figure 9C] FIG. 9C illustrates various designs for the pull tab according to some embodiments. [Figure 10] FIG. 10 illustrates a front view of a two-stage start-up PCB, according to some embodiments. [Figure 11] FIG. 11 illustrates a wound dressing layer of a wound dressing for use with an electronic assembly, according to some embodiments. [Figure 12A] FIG. 12A illustrates a wound dressing incorporating an electronic assembly within the wound dressing layer, according to some embodiments. [Figure 12B] FIG. 12B illustrates a cross-sectional layout of material layers of a wound dressing incorporating an electronic assembly within the dressing, according to some embodiments. [Figure 13] FIG. 13 illustrates a wound dressing incorporating an electronic assembly and a negative pressure indicator within the dressing layer, according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The embodiments disclosed herein relate to devices and methods for treating wounds with reduced pressure, including negative pressure sources and wound dressing components and devices, the devices and components including the material that overlays and packs the wound may be collectively referred to herein as a dressing.

[0020] It will be understood that throughout this specification, references will be made to wounds. It should be understood that the term wound is broadly interpreted to include open and closed wounds where the skin is torn, incised, or perforated, or where trauma causes bruising, or any other surface or other condition or defect in the skin of a patient, or others that would benefit from reduced pressure treatment. Thus, a wound is broadly defined as any damaged area of ​​tissue that may or may not generate fluid. Examples of such wounds include, but are not limited to, abdominal wounds, or other large or incisional wounds, as a result of either surgery, trauma, sternotomy, fasciotomy, or other conditions, dehiscence wounds, acute wounds, chronic wounds, subacute wounds and dehiscence wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, bruises, burns, diabetic ulcers, decubitus ulcers, stomas, surgical wounds, traumatic ulcers, and venous ulcers.

[0021] It will be appreciated that embodiments of the present disclosure are generally applicable for use with topical negative pressure ("TNP") treatment systems. In brief, negative pressure wound therapy may aid in the closure and healing of many forms of "hard to heal" wounds by reducing tissue edema, encouraging blood flow and granular tissue formation, and removing excessive exudate, reducing bacterial load (and therefore infection risk). In addition, treatment may reduce wound unrest, leading to faster healing. TNP treatment systems may also assist in the healing of surgically closed wounds by removing fluids and helping to stabilize tissues in an apposed position of closure. Further beneficial uses of TNP treatment may be found in grafts and flaps, where removal of excess fluid is important and grafts are required to be in close proximity to tissue to ensure tissue viability.

[0022] As used herein, a reduced pressure or negative pressure level, e.g., -XmmHg, represents a pressure level relative to normal ambient atmospheric pressure, which may correspond to 760mmHg (or 1 atm, 29.93 inHg, 101.325 kPa, 14.696 psi, etc.). Thus, a negative pressure value of -XmmHg reflects an absolute pressure of XmmHg less than 760mmHg, or in other words, an absolute pressure of (760-X)mmHg. Furthermore, a negative pressure "lower" or "smaller" than XmmHg corresponds to a pressure closer to atmospheric pressure (e.g., -40mmHg is lower than -60mmHg). A negative pressure "higher" or "larger" than -XmmHg corresponds to a pressure further from atmospheric pressure (e.g., -80mmHg is higher than -60mmHg). In some embodiments, the local ambient atmospheric pressure is used as a reference point, and such local pressure may not necessarily be, for example, 760mmHg.

[0023] The negative pressure range for some embodiments of the present disclosure may be about -80 mmHg, or about -20 mmHg to -200 mmHg. Note that these pressures are relative to normal ambient atmospheric pressure, which may be 760 mmHg. Therefore, -200 mmHg would be substantially about 560 mmHg. In some embodiments, the pressure range may be between about -40 mmHg and -150 mmHg. Alternatively, a pressure range of up to -75 mmHg, up to -80 mmHg, or greater than -80 mmHg may be used. Also, in other embodiments, a pressure range below -75 mmHg may be used. Alternatively, a pressure range of approximately -100 mmHg or even above -150 mmHg may be provided by the negative pressure device.

[0024] In some embodiments of the wound closure devices described herein, increased wound contraction can lead to increased tissue expansion in the surrounding wound tissue. This effect can be increased by varying the force applied to the tissue, for example, varying the negative pressure applied to the wound over time, possibly in conjunction with increasing the tensile force applied to the wound by the wound closure device embodiments. In some embodiments, the negative pressure can be varied over time, for example, using a sine wave, a square wave, and / or in synchronization with one or more patient physiological indicators (e.g., heart rate). Examples of such applications, further disclosure of which may be found in the foregoing, include U.S. Patent No. 8,235,955, entitled "Wound treatment apparatus and method," issued on August 7, 2012, and U.S. Patent No. 7,753,894, entitled "Wound cleansing apparatus with stress," issued on July 13, 2010. The disclosures of both of these patents are incorporated herein by reference in their entirety.

[0025] International Patent Application No. GB2012 / 000587, entitled "WOUND DRESSING AND METHOD OF TREATMENT," filed on July 12, 2012 and published on January 17, 2013 as International Patent Publication No. WO 2013 / 007973 A2, which is incorporated herein and is considered a part of this specification, relates to embodiments, methods of manufacture, and components of wound dressings and wound treatment devices that may be used in combination with or in addition to the embodiments described herein. Additionally, embodiments of the wound dressings, wound treatment devices, and methods described herein may be implemented in accordance with International Application No. PCT / IB2013 / 001469, entitled "APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY," filed May 22, 2013, and published on November 28, 2013 as WO 2013 / 175306; U.S. Patent Application No. 14 / 418,874, entitled "WOUND DRESSING AND METHOD OF TREATMENT," filed January 30, 2015, published as U.S. Publication No. 2015 / 0216733, and published on August 6, 2015; and U.S. Patent Application No. 14 / 418,874, entitled "WOUND DRESSING AND METHOD OF TREATMENT," filed January 30, 2015, published as U.S. Publication No. 2015 / 0190286, and published on July 9, 2015. No. 14 / 418,908, filed March 13, 2015, entitled "WOUND DRESSING AND METHOD OF TREATMENT," U.S. Patent Application No. 14 / 658,068, filed March 13, 2015, and U.S. Patent Application No. 2015 / 0182677, published July 2, 2015, entitled "WOUND DRESSING AND METHOD OF TREATMENT," which are hereby incorporated by reference in their entireties.Embodiments of the wound dressings, wound treatment devices, and methods described herein may be used in combination with or in addition to embodiments described in U.S. Application No. 13 / 092,042, entitled "WOUND DRESSING AND METHOD OF USE," filed on April 21, 2011 and published as U.S. Patent Publication No. 2011 / 0282309, which is incorporated herein by reference in its entirety, and which includes further details regarding wound dressing embodiments, wound dressing components and principles, and materials used in wound dressings.

[0026] In some embodiments, the negative pressure source (e.g., pump) and some or all other components of the TNP system, such as power sources, sensors, connectors, user interface components (buttons, switches, speakers, screens, etc.), may be integrated into the wound dressing. The wound dressing may include various layers of material as described herein and described in more detail in International Patent Application EP2017 / 055225, filed March 6, 2017, entitled "WOUND TREATMENT APPARATUSES AND METHODS WITH NEGATIVE PRESSURE SOURCE INTEGRATED INTO WOUND DRESSING." The layers of material may include a wound contact layer, one or more absorbent layers, one or more transmission or spacer layers, and a backing or cover layer that covers the one or more absorbent and transmission or spacer layers. The wound dressing is placed over the wound and sealed to the wound with the pump and / or other electronic components contained within the wound dressing under the cover layer. In some embodiments, the dressing may be provided as a single article with all wound dressing elements (including the pump) pre-attached and integrated into a single unit, hi some embodiments, the periphery of the wound contact layer may be attached to the periphery of a cover layer that surrounds all of the wound dressing elements, as illustrated in Figures 1A-1C.

[0027] In some embodiments, the pump and / or other electronic components may be configured to be disposed adjacent to or next to the absorbent and / or permeable layers such that the pump and / or other electronic components are still a single article applied to the patient. In some embodiments, the pump and / or other electronics are disposed away from the wound site. FIGS. 1A-1C illustrate wound dressings with a negative pressure source and / or other electronic components incorporated within the wound dressing. FIGS. 1A-1C illustrate wound dressings 100 with the pump and / or other electronics disposed away from the wound site. The wound dressing may include an electronics area 161 and an absorbent area 160. The dressing may include a wound contact layer 110 (not shown in FIGS. 1A-1B) and a moisture permeable film or cover layer 113 disposed over the contact layer and other dressing layers. The wound dressing layers and the components of the electronics area and absorbent area may be covered by one continuous cover layer 113 as shown in FIGS. 1A-1C.

[0028] The dressing may include a wound contact layer 110, a transmission layer 111, an absorbent layer 112, and a moisture permeable film 113 or cover layer 113 disposed over the wound contact layer, transmission layer, absorbent layer, or other layer of the dressing. The wound contact layer may be configured to contact the wound. The wound contact layer may include an adhesive on the side facing the patient to secure the dressing to the surrounding skin, or on the top side to secure the wound contact layer to a cover layer or other layer of the dressing. In operation, the wound contact layer may be configured to provide a unidirectional flow to facilitate removal of exudate from the wound while inhibiting or substantially preventing exudate from returning to the wound.

[0029] The wound contact layer 110 may be a polyurethane layer, a polyethylene layer, or other flexible layer that has been perforated or otherwise rendered liquid and gas permeable, for example, via a hot pin process, a laser ablation process, or an ultrasonic process, or in some other manner. The wound contact layer 110 has a lower surface and an upper surface. The perforations preferably include through holes in the wound contact layer 110, thereby allowing fluids to flow through the layer 110. The wound contact layer 110 helps to prevent tissue ingrowth into other materials of the wound dressing. The perforations are preferably small enough to meet this requirement while allowing fluids to flow therethrough. For example, perforations formed as slits or holes having dimensions in the range of 0.025 mm to 1.2 mm are believed to be small enough to help prevent tissue ingrowth into the wound dressing while allowing wound exudate to flow into the dressing. In some configurations, the wound contact layer 110 may help maintain the integrity of the entire dressing 100 while also creating an airtight seal around the absorbent pad to maintain negative pressure at the wound.

[0030] Some embodiments of the wound contact layer 110 may also serve as a carrier for optional upper and lower adhesive layers (not shown). For example, a low pressure sensitive adhesive may be provided on the lower surface of the wound dressing 100 and a high pressure sensitive adhesive may be provided on the upper surface of the wound contact layer. The pressure sensitive adhesive, which may be a silicone, hot melt, hydrocolloid or acrylic based adhesive, or other such adhesive, may be formed on both sides of the wound contact layer, or on any selected side, or on neither side of the wound contact layer. When a lower pressure sensitive adhesive layer is utilized, it may help adhere the wound dressing 100 to the skin around the wound site. In some embodiments, the wound contact layer may include a perforated polyurethane film. The lower surface of the film may be provided with a silicone pressure sensitive adhesive and the upper surface may be provided with an acrylic pressure sensitive adhesive, which may help the dressing maintain its integrity. In some embodiments, an adhesive layer may be provided on both the upper and lower surfaces of the polyurethane film layer, and all three layers may be perforated together.

[0031] A layer of porous material 111 may be disposed above the wound contact layer 110. As used herein, the terms porous material, spacer, and / or permeable layer may be used interchangeably to refer to a layer of material within the dressing configured to distribute negative pressure across the wound area. This porous or permeable layer 111 allows fluids, including liquids and gases, to permeate away from the wound site into the upper layers of the wound dressing. In particular, the permeable layer 111 may ensure that an open air channel is maintained to transmit negative pressure over the wound area even if the absorbent layer absorbs a significant amount of exudate. The layer 111 should preferably remain open under normal pressures that would be applied during negative pressure wound therapy, as described above, so that the entire wound site experiences equal negative pressure. The layer 111 may be formed from a material having a three-dimensional structure. For example, a knitted or woven spacer fabric (e.g., Baltex 7970 weft knit polyester), or a nonwoven fabric may be used.

[0032] The transmission layer assists in distributing negative pressure over the wound site and facilitating transport of wound exudate and fluids into the wound dressing, hi some embodiments, the transmission layer may be formed at least in part from three-dimensional (3D) fibers.

[0033] In some embodiments, the transmission layer 111 comprises a 3D polyester spacer fabric layer including a top layer (i.e., the layer distal from the wound bed during use) that is 84 / 144 woven polyester, a bottom layer (i.e., the layer that is placed proximal to the wound bed during use) that is 10 denier flat polyester, and a third layer sandwiched between these two layers that is an area defined by woven polyester viscose, cellulose or similar monofilament fibers. Other materials and fibers of other linear mass densities may of course be used.

[0034] Throughout this disclosure, reference will be made to monofilament fibers, although it will of course be understood that multiple yarn alternatives may be utilized, and thus the top spacer fabric will have more filaments in the single yarn used to form it than the number of filaments making up the yarn used to form the bottom spacer fabric layer.

[0035] This difference in filament counts of the spaced layers helps to control moisture flow across the transmission layer. Specifically, by having a higher filament count in the top layer, i.e., the top layer is made from yarns having more filaments than the yarns used in the bottom layer, liquids tend to wick more along the top layer than the bottom layer. In use, this difference causes liquids to be drawn away from the wound bed and into the central region of the dressing where the absorbent layer 112 can help contain the liquid or wick it forward toward the cover layer 113 where it can be released.

[0036] Preferably, to improve liquid flow across the permeable layer 111 (i.e. perpendicular to the channel area formed between the top and bottom spacer layers), the 3D fabric may be treated with a dry cleaning agent (such as, but not limited to, perchloroethylene) to help remove any conventionally used industrial products such as mineral oils, fats, or waxes that may interfere with the hydrophilic function of the permeable layer. In some embodiments, this may be followed by an additional manufacturing step in which the 3D spacer fabric is washed with a hydrophilic agent (such as, but not limited to, Feran Ice 30 g / l, available from Rudolph Group). This process step helps ensure that the surface tension of the material is low enough that liquids such as water can enter the fabric as soon as they come into contact with the 3D knit. This step also helps to control the flow of the liquid insult component of any exudate.

[0037] Additionally, an absorbent layer (such as layer 112) may be utilized to absorb and retain exudate drawn from the wound. In some embodiments, a superabsorbent material may be used in absorbent layer 112. In some embodiments, the absorbent body comprises a shaped superabsorbent layer configuration.

[0038] A layer of absorbent material 112 is provided over the transmission layer 111. The absorbent material, which may include foam or nonwoven natural or synthetic materials and may optionally include superabsorbent materials, forms a reservoir for fluids, particularly liquids, that are removed from the wound site. In some embodiments, layer 111 may also help draw fluids toward the cover layer 113.

[0039] The material of the absorbent layer 112 may also prevent liquid collected within the wound dressing from flowing freely within the dressing, and preferably acts to contain any collected liquid within the dressing. The absorbent layer 112 also helps distribute the fluid throughout the layer by wicking, drawing fluid away from the wound site and storing it throughout the absorbent layer. This helps prevent clumping in the area of ​​the absorbent layer. The capacity of the absorbent material must be sufficient to manage the rate at which the wound exudate flows when negative pressure is applied. During use, the absorbent layer experiences negative pressure, so the material of the absorbent layer is chosen to absorb liquid under such conditions. There are several materials, for example superabsorbent materials, that can absorb liquid when under negative pressure. The absorbent layer 112 may typically be made of ALLEVYN™ foam Freudenberg 114-224-4 or Chem-Posite™ 11C-450. In some embodiments, the absorbent layer 112 may comprise a composite including superabsorbent powder, a fibrous material such as cellulose, and a bonding fiber. In a preferred embodiment, the composite is an airlaid, thermally bonded composite.

[0040] In some embodiments, the absorbent layer 112 is a layer of non-woven cellulose fibers with superabsorbent material in the form of dry particles dispersed throughout the layer. The use of cellulose fibers introduces a fast wicking element that helps to quickly and evenly distribute liquid absorbed by the dressing. The juxtaposition of many twist-like fibers leads to strong capillary action of the fibrous pad that helps to distribute the liquid, thus efficiently delivering liquid to the superabsorbent material. The wicking action also helps to bring the liquid into contact with the top cover layer, which helps to increase the transpiration rate of the dressing.

[0041] The wound dressing layer and absorbent layer of the electronics area may be covered by one continuous cover or backing layer 113. As used herein, the terms cover layer and / or backing layer may be used interchangeably to refer to a layer of material within the dressing that covers the underlying dressing layer and is configured to seal to the wound contact layer and / or skin surrounding the wound. In some embodiments, the cover layer may comprise a moisture permeable material that prevents the passage of liquid exudate and other liquids removed from the wound while allowing the passage of gases.

[0042] The cover layer 113 is preferably gas impermeable but water vapor permeable and may extend across the width of the wound dressing 100. The cover layer 113, which may for example be a polyurethane film (e.g. Elastollan SP9109) with a pressure sensitive adhesive on one side, is impermeable to gas and therefore acts to cover the wound and seal the wound cavity over which the wound dressing is placed. In this way, an effective chamber is created between the cover layer 113 and the wound site, in which a negative pressure can be established. The cover layer 113 is preferably sealed, for example via adhesive or welding techniques, to the wound contact layer 110 in a border area around the dressing to prevent air from being drawn into the border area. The cover layer 113 protects the wound from external bacterial contamination (bacterial barrier) and allows liquid from the wound exudate to migrate through the layer and evaporate from the film outer surface. The cover layer 113 preferably includes two layers: a polyurethane film and an adhesive pattern spread over the film. The polyurethane film is preferably moisture permeable and may be made from a material that has a high water transmission rate when wet. In some embodiments, the moisture permeability of the cover layer increases when the cover layer becomes wet. The moisture permeability of the wet cover layer may be up to about ten times that of the dry cover layer.

[0043] The electronics area 161 may include a negative pressure source (e.g., a pump) and some or all other components of a TNP system that may be integrated with the wound dressing, such as power sources, sensors, connectors, user interface components (buttons, switches, speakers, screens, etc.), etc. For example, the electronics area 161 may include a button or switch 114, as shown in Figures 1A and 1B. The button or switch 114 may be used to operate the pump (e.g., turn the pump on / off).

[0044] The absorbent area 160 may comprise the absorbent material 112 and may be disposed over the wound site. The electronics area 161 may be disposed away from the wound site, such as by being offset laterally from the absorbent area 160. As shown in FIGS. 1A-1C, the electronics area 161 may be disposed adjacent to and in fluid communication with the absorbent area 160. In some embodiments, the electronics area 161 and the absorbent area 160 may each be rectangular and disposed adjacent to one another. In FIG. 1C, the electronics area 161 is described as area "A" and the absorbent area 160 is described as area "B". In some embodiments, as illustrated in FIG. 1C, the electronic component 150 may be positioned within a recess or cutout in the absorbent material 112, but may be disposed away from the sides of the absorbent area. As shown in the cross-sectional view of the wound dressing layer in FIG. 1C, the absorbent material 112 may be positioned on either side of the electronic component 150.

[0045] In some embodiments, additional layers of dressing material may be provided in the electronics area 161, the absorbent area 160, or both. In some embodiments, the dressing may include one or more transmission or spacer layers and / or one or more absorbent layers disposed above the wound contact layer 110 and below the cover layer 113 of the dressing.

[0046] In some embodiments, the electronics area 161 of the dressing may include electronic components 150. In some embodiments, the electronics area 161 of the dressing may include one or more layers of transparent or spacer and / or absorbent material, and the electronic components 150 may be embedded within the one or more layers of transparent or spacer and / or absorbent material. The layers of transparent or absorbent material may have recesses or cutouts for embedding the electronic components 150 therein while providing structure to prevent collapse. The electronic components 150 may include pumps, power sources, controllers, and / or electronics packages.

[0047] A pump exhaust may be provided to exhaust air from the pump to the outside of the dressing. The pump exhaust may be in communication with the electronics area 161 and the exterior of the dressing.

[0048] As used herein, the top layer, uppermost layer or upper layer refers to the layer furthest from the surface of the skin or wound while the dressing is in use and placed on the wound. Accordingly, the bottom layer, lowermost layer or lower layer refers to the layer closest to the surface of the skin or wound while the dressing is in use and placed on the wound. Additionally, a layer may have a proximal surface facing the wound, referred to as the side or surface of the layer closest to the skin or wound, and a distal surface, referred to as the side or surface of the layer furthest from the skin or wound.

[0049] 1A-1C illustrate wound dressing devices incorporating a pump and / or other electronic components within the wound dressing and offset from the absorbent layer. In some embodiments, as shown in FIG. 1C, the absorbent area 160 includes a transmission layer 111 disposed above the wound contact layer 110. The absorbent layer 112 may be provided above the transmission layer 111. In some embodiments, the electronics area 161 may include an electronic unit (as shown in FIGS. 2A-2B). In some embodiments, the electronic unit is provided directly above the wound contact layer. In other embodiments, the electronic unit may be disposed above a layer of wicking, absorbent, or permeable material located above the wound contact layer 110 of the dressing. For example, as shown in FIG. 1C, the electronic unit 150 may be disposed above the transmission layer 111. In some embodiments, the transmission layer 111 may be a single layer of material that extends below the electronic unit 150 and the absorbent material 112. Thus, in some embodiments, the transmission layer 111 extends continuously through the absorbent area 160 and the electronics area 161. In alternative embodiments, the transmission layer beneath the electronic unit may be a different transmission layer than the transmission layer beneath the absorbent material 112. As shown in Figures 1A-1C, the transmission layer 111, absorbent material 112, and electronic unit 150 may be covered with a cover layer 113 that seals around the wound contact layer 110.

[0050] The electronics area 161 may include an electronics unit 150 located beneath the cover layer 113 of the dressing. In some embodiments, the electronics unit may be surrounded by a material to enclose or encapsulate the negative pressure source and electronic components by enclosing the electronics. In some embodiments, this material may be a casing. In some embodiments, the electronics unit may be encapsulated or surrounded by a protective coating, such as, for example, a hydrophobic coating as described herein. The electronics unit may be in contact with the dressing layer of the absorbent area 160 and may be covered by the cover layer 113. As used herein, the electronics unit includes a lower or wound-facing surface closest to the wound and an opposing top surface furthest from the wound when the wound dressing is placed over the wound.

[0051] 1C illustrates one embodiment of a wound dressing that incorporates within the dressing an electronic unit 150. In some embodiments, the electronic subassembly or electronic unit 150 may be embedded in an opening or hole in the absorbent layer 112 toward one end of the dressing, as shown in FIG.

[0052] In some embodiments, the absorbent component and the electronics component may overlap but be offset. For example, a portion of the electronics area may overlap the absorbent area, e.g., the superabsorbent layer, but the electronics area is not completely above the absorbent area. Thus, a portion of the electronics area may be offset from the absorbent area. The dressing layer and electronic components may be surrounded by a cover layer 113 positioned above the absorbent layer 112 and the electronics 150, with the wound contact layer 110 positioned below the bottom layer. The wound contact layer 110 and the cover layer 113 may be sealed at the periphery surrounding the dressing components. In some embodiments, the cover layer may be in direct physical contact with the absorbent material and / or the electronic unit. In some embodiments, the cover layer may be sealed to a portion of the electronic unit and / or casing, for example, in areas where holes or openings are used to accommodate the electronic components (e.g., switches and / or vents).

[0053] 2A-2B illustrate an embodiment of an electronic unit 267 that may be incorporated into a wound dressing. FIG. 2A illustrates a top view of the electronic unit. FIG. 2B illustrates the bottom or wound-facing surface of the electronic unit. The electronic unit 267 may include a pump 272 and one or more batteries 268. The electronic unit 267 may include a flexible circuit board 276 configured to be in electrical communication with the pump 272 and / or the batteries 268.

[0054] As shown in FIG. 2A, the electronic unit 267 may include a single button or switch 265 on the top surface of the unit. The single button or switch 265 may be used as an on / off button or switch to stop and start operation of the pump and / or electronic components. The switch 265 may be a dome switch configured to be located on top of the pump. Since the switch is located within the dressing, the cover layer may simply be sealed around or over the switch. In some embodiments, the cover layer may have an opening or hole located over the switch. The cover layer may be sealed around the perimeter of the switch 265 to maintain negative pressure under the wound cover. The switch may be located on any surface of the electronic unit and may be in electrical communication with the pump.

[0055] The electronic unit 267 may also include one or more vents or exhaust openings 264 on the flexible circuit board to exhaust air exhausted from the pump. As shown in FIG. 2B, a pump outlet exhaust mechanism 274 may be attached to the outlet of the pump 272. The vent or exhaust opening 264 may be located at the outlet of the pump and in fluid communication with the pump exhaust mechanism 274 that extends to the underside of the flexible circuit board. In some embodiments, the exhaust vent 264 on the flexible circuit board communicates with the top side of the dressing, allowing the pump exhaust to be exhausted from the electronic unit. In some embodiments, the exhaust mechanism 274 may be attached to the outlet end of the pump and may extend from the pump at a 90 degree angle from the pump orientation to communicate with the bottom side of the flexible circuit board. In some embodiments, the exhaust mechanism 274 may include an antimicrobial membrane and a check valve. In some embodiments, the exhaust vent 264 may include an antimicrobial membrane and a check valve. Air exhausted from the pump may pass through the pump outlet and exhaust mechanism 274. In some embodiments, the cover layer 113 may include an opening or hole located above the exhaust vent 264 and / or the membrane. The cover layer 113 may be sealed around the periphery of the exhaust port 264 to maintain a negative pressure under the wound cover 113. In some embodiments, the exhausted air may be exhausted through a gas or moisture permeable material of the cover layer. In some embodiments, the cover layer need not include an opening or hole over the exhaust port, and the exhausted air is exhausted through the cover layer. In some embodiments, the pump outlet mechanism 274 may be a custom part formed to fit around the pump as shown in FIG. 2B. The electronic unit 267 may include a pump inlet protection mechanism 280 located on the portion of the electronic unit closest to the absorbent area and aligned with the inlet of the pump 272 as shown in FIG. 2C. The pump inlet protection mechanism 280 is positioned between the pump inlet and the absorbent area or layer of the dressing. The pump inlet protection mechanism 280 may be formed of a hydrophobic material to prevent fluid from entering the pump 272.

[0056] In some embodiments, the top surface of the electronics unit may include one or more indicators 266 to indicate the status of the pump and / or the pressure level within the dressing. The indicators may be small LED lights or other light sources visible through a dressing component on the indicator or through holes in the dressing component. The indicators may be green, yellow, red, orange, or any other color. For example, there may be two lights, one green light and one orange light. A green light may indicate that the device is working properly and an orange light may indicate that there is some problem with the pump (e.g., a dressing leak, a dressing saturation level, and / or a low battery condition).

[0057] 2A and 2B illustrate an embodiment of an electronics unit 267. The electronics unit 267 may include a pump 272 and one or more batteries 268 or other power sources for powering the pump 272 and other electronics. The pump may operate at about 27 volts, or about 30 volts. Two batteries may allow for a more efficient voltage increase (6V to 30V) than is possible with a single battery.

[0058] The battery 268 may be in electrical communication with the flexible circuit board 276. In some embodiments, one or more battery connections are connected to a surface of the flexible circuit board 276. In some embodiments, the flexible circuit board may have other electronics therein. The flexible circuit board may have various sensors including, for example, but not limited to, one or more pressure sensors, temperature sensors, optical sensors and / or cameras, and / or saturation indicators.

[0059] In such embodiments, the components of the electronics unit 267 may include a protective coating to protect the electronics from the fluid of the dressing. The coating may provide a means of fluidic isolation between the electronics unit 267 and the absorbent material of the dressing. The coating may be a hydrophobic coating, including but not limited to a silicone coating or a polyurethane coating. In some embodiments, the electronics unit 267 may be enclosed within a protective housing or enclosure, as described in more detail herein. The pump inlet component may be used to protect the pump from fluid on the inlet, and the pump outlet mechanism may include a check valve to protect fluid from entering the outlet, as described in more detail in connection with International Application No. PCT / EP2017 / 055225, filed March 6, 2017, entitled "WOUND TREATMENT APPARATUSES AND METHODS WITH NEGATIVE PRESSURE SOURCE INTEGRATED INTO WOUND DRESSING," and International Application No. PCT / EP2017 / 059883, filed April 26, 2017, entitled "WOUND DRESSINGS AND METHODS OF USE WITH INTEGRATED NEGATIVE PRESSURE SOURCE HAVING A FLUID INGRESS INHIBITION COMPONENT," which are incorporated herein by reference in their entireties.

[0060] The electronic unit 267 includes one or more slits, grooves or recesses 271 between the pump and the two batteries. The slits, grooves or recesses 271 may allow the electronic unit 267 to flex and conform to the shape of the wound. The unit 267 may have two parallel slits, grooves or recesses 271 that form three segments of the electronic unit 267. The slits, grooves or recesses 271 in the unit 267 create gaps that allow for flexibility of the electronic unit at or near the hinge points. The pump exhaust vent 264, switch 265, and indicator 266 are shown on the top surface of the electronic unit 267. As shown, one embodiment of the electronic unit 267 has two hinge points to separate the unit into three regions or panels, for example, one that includes a battery, one that houses a pump, and one that houses another battery. In some embodiments, the slits, grooves or depressions extend parallel to a longitudinal axis of the covering that extends along the length of the covering through the absorbent area of ​​the covering, through the electronics area of ​​the covering.

[0061] Figure 3A illustrates one embodiment of a wound dressing layer incorporating electronic components within the wound dressing. Figure 3A illustrates a wound dressing having a wound contact layer 310 configured to contact the wound. A transmission or spacer layer 311 is provided over the wound contact layer. The transmission layer 311 may assist in delivering and distributing negative pressure over the wound site.

[0062] A first layer of apertured absorbent material 351 may be provided over the transmissive layer 311. The first apertured absorbent layer 351 may include one or more apertures 329. In some embodiments, the apertures 329 may be sized and shaped to fit the electronics unit 350 therein. The first apertured absorbent layer 351 may be sized and shaped to fit the dimensions of the electronics area and does not extend into the absorbent area. In some embodiments, the apertures 329 may be sized and shaped to fit the individual components of the electronics unit 350 therein.

[0063] An absorbent layer 322 with a second opening may be provided over the first absorbent layer 351. In some embodiments, the second absorbent layer 322 includes one or more openings 328. The second absorbent layer 322 may be sized and shaped to accommodate the dimensions of the electronics area and the absorbent area. In some embodiments, the openings 328 may be sized and shaped to fit individual components of the electronics unit 350.

[0064] The electronic unit 350 may be positioned at the openings 328 and 329 of the first absorbent material 351 and the second absorbent material 322. The electronic unit 350 may include a pump 327, a power supply 326, and a printed circuit board 381. In some embodiments, the pump 327 may include a pump inlet mechanism 710 and an outlet mechanism 382. In some embodiments, the printed circuit board 381 may include electronics including, but not limited to, switches, sensors, and LEDs as described herein. In some embodiments, the circuit board 381 may include one or more holes positioned over one or more exhaust vents (not shown) in the outlet mechanism 382, ​​as described in more detail herein.

[0065] An overlay layer 317 may be provided over the electronic components 350 and the absorbent layer 322. In some embodiments, the overlay layer 317 may be one or more layers of absorbent and / or permeable materials as described herein. In some embodiments, the overlay layer 317 may include a conformable material that overlaps the periphery and borders the underlying layers of permeable and absorbent materials. In some embodiments, the overlay layer 317 may soften the edges of the wound dressing layer by reducing the contour around the edges of the dressing layer. The overlay layer 317 may protect the cover layer from being punctured by the underlying layer when the cover layer is sealed over the underlying dressing layer. The overlay layer 317 may include an opening 371 that allows access to at least a portion of the underlying electronic unit 350.

[0066] A cover layer or backing layer 313 may be disposed over the overlay layer 317. In some embodiments, when the overlay layer 317 is not used, the cover layer or backing layer 313 may be provided over the absorbent layer 322 and / or the electronic components 350. The cover layer 313 may form a seal with the wound contact layer 310 in a peripheral area surrounding the overlay layer 317, the absorbent layers 322 and 351, the electronic components 350, and the transmission layer 311. In some embodiments, the cover layer 313 may be a sheet of flexible material that forms and molds around the dressing component when the dressing component is applied to the wound. In other embodiments, as shown in FIG. 3A, the cover layer 313 may be a preformed or premolded material to fit around the dressing component. As used herein, the terms cover layer and backing layer may be used interchangeably to refer to a layer of material within the dressing that is configured to cover the dressing layer.

[0067] In some embodiments, the cover or backing layer 313 may include an opening 372. The opening 372 may be positioned over at least a portion of the opening 371 in the overlay layer 317 to allow access to at least a portion of the underlying electronics unit 350. In some embodiments, the openings 371 and 372 may allow access to a switch and / or a vent at the pump outlet.

[0068] A label 341 may be provided over the openings 371 and 372 and positioned over the exposed portions of the electronic components 350. The label may include a vent 342, an indicator portion 344, and / or a switch cover 343. The indicator portion 344 may include a hole or transparent area 344 for placement over one or more indicators or LEDs on the printed circuit board 381 below the label 341. The hole or transparent area 344 may allow the indicators or LEDs to be visible through the label 341. In some embodiments, the switch cover 342 may include a dome-shaped cover positioned over the switches on the printed circuit board 381. In some embodiments, the label 341 may include embossed features for the switch cover 342. In some embodiments, the embossed features of the switch cover 342 may prevent accidental activation or deactivation of the device. In some embodiments, the switch or switch cover 342 may include a tab on the switch to prevent accidental activation or deactivation. A vent 342 in the label may allow exhaust air from the pump outlet mechanism to pass through the label, exit the wound dressing and vent to the atmosphere.

[0069] In some embodiments, the label may be positioned over the cover or backing layer 313. The label may seal to the cover layer to form a seal over the wound. In other embodiments, the label 341 may be positioned over the overlay layer 371 and under the cover or backing layer 313. In such embodiments, the cover layer 313 may have one or more openings over one or more components of the label 341. For example, the cover layer 313 may have openings over the vent 342, the indicator portion 344, and / or the switch cover 343.

[0070] 3B illustrates a cross-sectional layout of material layers of a wound dressing incorporating an electronics assembly within the dressing. Dressing 300 includes multiple material layers and an electronics assembly 350. Wound dressing 300 may include an electronics area 361 including electronics and an absorbent area or dressing area 360 intended to be applied to a wound as described with reference to FIGS. 1A-1C.

[0071] As described herein, one or more layers of material may extend over both the electronics area 361 and the dressing area 360. The dressing 300 may include a wound contact layer 310, a transmission layer 311, absorbent layers 322 and 351, an overlay layer 317, and a cover or backing layer 313, as illustrated in FIG. 3B. The absorbent layers 322 and 351 may include recesses or cutouts for receiving components of the electronic assembly 350 described herein. In some embodiments, the absorbent layer 351 with the small openings may be positioned above the absorbent layer 322 with the large openings, as shown in FIG. 3B. In other embodiments, the absorbent layer 351 with the small openings may be positioned below the absorbent layer 322 with the large openings, as shown in FIG. 3A.

[0072] In some embodiments, overlay layer 317 and / or cover layer 313 may include cutouts or openings positioned over switches and / or indicators of electronic assembly 350. Label or cover 341 may be positioned to cover at least a portion of electronic assembly 350 and any cutouts in overlay layer 317 and / or cover layer 313. Label or cover 341 may be similar to label or cover 341 as described above with reference to FIG.

[0073] Prior to use, the dressing may include a delivery layer 345 adhered to the bottom surface of the wound contact layer. The delivery layer 345 may cover the adhesive or openings on the bottom surface of the wound contact layer 310. In some embodiments, the delivery layer 345 may provide support to the dressing and aid in sterilization and proper placement of the dressing on the patient's wound and skin. The delivery layer 345 may include a handle 346 that a user may use to separate the delivery layer 345 from the wound contact layer 310 before applying the dressing 300 to the patient's wound and skin.

[0074] FIG. 3C illustrates a top view of an embodiment of a wound dressing layer incorporating an electronic assembly within the dressing.

[0075] FIG. 3C shows a cover layer 313 and electronics cover 341 covering the overlay layer 317 and the underlying dressing and electronics components. The cover layer 313 may seal to the wound contact layer 310 at the peripheral area of ​​the wound contact layer 310. In some embodiments, a label or electronics cover 341 may be positioned over the cover layer 313. In other embodiments, the cover layer 313 may seal over the electronics cover 341. In some embodiments, the cover layer 313 may include one or more holes in the cover layer 313 positioned over the switch and / or pump outlet vent. In some embodiments, the cover layer 313 may include a single hole positioned over the switch cover 343, visual indicator 344, and / or pump outlet vent 342 of the cover or label 341, as shown in FIG. 3C. In some embodiments, the label may include an embossed feature for the switch cover 343. In some embodiments, the embossed feature of the switch cover 343 may prevent accidental activation or deactivation of the device. In some embodiments, the switch or switch cover 343 may include a tab on the switch to prevent accidental activation or deactivation.

[0076] The visual indicator 344 may provide an indication of the operation of the negative pressure source and / or the level of negative pressure being applied to the wound. In some embodiments, the visual indicator may include one or more light sources or LEDs. In some embodiments, the visual indicator light source illuminates to indicate a state or change in state. In some embodiments, the light source may illuminate a particular sequence and / or color to indicate a state. For example, in some embodiments, the light source may blink to notify the user that the device is operating properly. In some embodiments, the light source may automatically blink periodically and / or the light source may be activated by a switch or other button to illuminate to indicate a state.

[0077] In some embodiments, the switch is pressed and / or depressed to power the dressing and electronics on and off. In some embodiments, when the switch is activated, the pump and associated color LED, e.g., a green LED, may be used to confirm that the dressing and integrated negative pressure source are operational. In some embodiments, during operation of the pump and dressing, the pump and dressing may enter a fault state, indicated by a color LED, e.g., an amber LED.

[0078] Reduced Pressure Therapy Systems and Methods 4 illustrates a negative pressure therapy system 100 including a TNP device 11 applicable over a wound 14, according to some embodiments. The TNP device 11 may be used to treat the wound 14. The TNP device 11 may include a controller 12A, a memory 12B, a negative pressure source 12C, a user interface 12D, a power source 12E, a first pressure sensor 12F, and a second pressure sensor 12G configured to be in electrical communication with each other. Additionally, the TNP device 11 may include a wound dressing 13. The power source 12E may provide power to one or more components of the TNP device 11.

[0079] One or more of the controller 12A, memory device 12B, negative pressure source 12C, user interface 12D, power source 12E, first pressure sensor 12F, and second pressure sensor 12G may be integrated with, incorporated as part of, attached to, or located within the wound dressing 13. Thus, the TNP device 11, with its control electronics, may be considered to be mounted on and pumping the wound dressing 13, rather than being separate from the wound dressing 13.

[0080] The controller 12A may be a microcontroller or microprocessor. The controller 12A may control the operation of one or more other components of the TNP device 11 according to instructions stored at least in the memory device 12B. For example, the controller 12A may control the operation and delivery of negative pressure by the negative pressure source 12C. The controller 12A may be a primary controller, and the TNP device 11 may include one or more additional controllers as described herein.

[0081] The negative pressure source 12C may include pumps such as, but not limited to, rotary diaphragm pumps or other diaphragm pumps, piezoelectric pumps, peristaltic pumps, piston pumps, rotary vane pumps, liquid ring pumps, scroll pumps, pumps operated by piezoelectric transducers, or any other suitable pumps or micropumps, or any combination of the above. The pumps may include actuators powered by energy sources such as electrical energy and mechanical energy. For example, the actuators may be electric motors, piezoelectric transducers, voice coil actuators, electroactive polymers, shape memory alloys, comb drives, hydraulic motors, pneumatic actuators, jackscrews, servo mechanisms, solenoid actuators, stepper motors, plungers, combustion engines, and the like. In some embodiments, the negative pressure source 12C may provide negative pressure by converting electrical energy to mechanical energy without converting electrical energy to magnetic energy. In such embodiments, the negative pressure source 12C may have a different effect when electrically coupled to one or more other components of the controller 12A than if the negative pressure source 12C provided negative pressure by converting electrical energy to magnetic energy and then to mechanical energy.

[0082] The user interface 12D may include one or more elements that receive user input or provide user output to the patient or caregiver. The one or more elements that receive user input may include a button, a switch, a dial, or a touch screen, and the one or more elements that provide user output may include activation of a light emitting diode (LED) or activation of one or more pixels of a display, or activation of a speaker, and the like. In one example, the user interface 12D may include a switch for receiving user input (e.g., input for activation or deactivation of negative pressure) and two LEDs for indicating the operational state of the TNP device 11 (e.g., functioning normally, a fault, or waiting for user input). The user interface 12D may also include an input element that changes the state of the controller 12A by using a switching mechanism such as a pull tab (further described with respect to FIGS. 8A and 8B).

[0083] The first pressure sensor 12F may be used to monitor the pressure below the wound dressing 13, such as the pressure in a fluid flow path connecting the negative pressure source 12C and the wound 14, the pressure at the wound 14, or the pressure at the negative pressure source 12C. The second pressure sensor 12G may be used to monitor the pressure outside the wound dressing 13. The pressure outside the wound dressing may be atmospheric pressure, although atmospheric pressure may vary depending on, for example, the altitude used, or the pressure regulated environment in which the TNP device 11 may be used.

[0084] The controller 12A can control the supply of negative pressure by the negative pressure source 12C by at least comparing the pressure monitored by the first pressure sensor 12F to the pressure monitored by the second pressure sensor 12G.

[0085] The wound dressing 13 may comprise a wound contact layer, a spacer layer, and an absorbent layer. The wound contact layer may be in contact with the wound 14. The wound contact layer may comprise an adhesive on a side facing the patient to secure the dressing to the skin surrounding the wound 14, or may comprise an adhesive on an upper side to secure the wound contact layer to a cover layer or other layer of the wound dressing 13. In operation, the wound contact layer may provide unidirectional flow to facilitate removal of exudate from the wound while inhibiting or substantially preventing exudate from returning to the wound 14. The spacer layer may facilitate distribution of negative pressure over the wound site to facilitate transport of wound exudate and fluids into the wound dressing 13. Additionally, the absorbent layer may absorb and retain exudate drawn from the wound 14.

[0086] The controller 12A can monitor the operation of the negative pressure source 12C, which can include monitoring the duty cycle of the negative pressure source 12C (e.g., the duty cycle of the actuator of the negative pressure source). As used herein, "duty cycle" can represent the amount of time that the negative pressure source 12C is on or running over a period of time. In other words, the duty cycle can represent the time that the negative pressure source 12C is on as a percentage of the total time of interest. The duty cycle measurement can represent the level of operation of the negative pressure source 12C. For example, the duty cycle can indicate that the negative pressure source 12C is operating normally, working well, working extremely well, etc. Additionally, the duty cycle measurement, such as a periodic duty cycle measurement, can represent various operating conditions, such as the presence or degree of leakage, or the flow rate of fluid (e.g., air, liquid, or solid exudate, etc.) aspirated from the wound. Based on the duty cycle measurements, such as by comparing the measured duty cycle to a set of thresholds (e.g., calculated during calibration), the controller can implement or can be programmed to implement an algorithm or logic that controls operation of the system. For example, the duty cycle measurements can indicate that there is a large leak, and the controller 12A can be programmed to indicate this condition to a user (e.g., a patient, caregiver, or physician), or can be programmed to temporarily interrupt or pause operation of the negative pressure source to conserve power.

[0087] When the TNP device 11 may be used to treat a wound 14, the wound dressing 13 may create a substantially sealed or enclosed space around and under the wound 13, and the first pressure sensor 12F may periodically or continuously measure or monitor the pressure level of this space. The controller 12A may control the pressure level of this space between a first negative pressure setpoint limit and at least a second negative pressure setpoint limit. In some examples, the first setpoint limit may be about -70 mmHg, or may be about -60 mmHg or less to about -80 mmHg or more. In some examples, the second setpoint limit may be about -90 mmHg, or may be about -80 mmHg or less to about -100 mmHg or more. The controller 12A may operate the negative pressure source 12C to maintain a lower pressure at the first pressure sensor 12F than the ambient air at the second pressure sensor 12G.

[0088] Sterilization of TNP equipment As discussed, TNP systems vary in size from small to large. Also, as described in connection with Figures 1A-3C, some TNP systems have electronics and power sources integrated into the dressing. These integrated systems can advantageously provide faster and easier application of operation, improved portability, less maintenance hassle, and simpler appearance. However, while integrated TNP systems offer these and many other advantages, the safe production and operation of the system presents its own challenges with respect to sterilization of the system.

[0089] Since the TNP system is applied to the wound, it is important that the system and its components are free of bacteria. The risk of bacterial infection can undermine the wound healing purpose of the TNP system. For non-integrated TNP systems, with the boron pump and pump electronics located away from the dressing, the issue of sterilization is simpler, since the dressing can be sterilized separately from the pump and pump electronics. The dressing, pump, and pump electronics can be sterilized with low-temperature sterilization techniques, such as passing an antibacterial gas through the dressing. In some embodiments, ethylene oxide (Eto) can be used for sterilization, since it is a colorless gas that effectively attacks cellular proteins and microbial nucleic acids. The sterilized dressing can be applied on or near the wound, and the negative pressure pump can then be connected to the dressing and activated for operation.

[0090] However, in some cases, sterilization of integrated negative pressure wound therapy systems is not a simple matter. Because the power supply, electronics, and negative pressure source may be located within or on the dressing, using the same or similar sterilization techniques for a non-integrated TNP system may expose the other components to the sterilizing gas. This exposure can be problematic because Eto is flammable.

[0091] In some implementations, non-integrated devices can be powered using replaceable batteries, which may be disconnected from the electronics so that power to the electronics is removed during sterilization, thereby preventing the electronics from having stored energy that could pose a risk of igniting the EtO during sterilization.

[0092] In some embodiments, the integrated system includes a non-removable power source disposed within or on the wound dressing. This presents a risk of inadvertent activation of the TNP system during sterilization, which may be a portion of the electronic energy from the power source that is stored in one or more energy storage components of the TNP system electronics, such as a capacitor. Release of such stored energy may result in over-rating during sterilization, generation of sparks, and / or ignition of the sterilizing gas. Thus, the risk of sudden energy release during the sterilization process should be addressed.

[0093] In some embodiments, the power source can be isolated from the remaining electronics of the integrated TNP system so that unwanted release of energy is avoided. This can be accomplished by isolating the power source from the electronics during sterilization and including two (or more) circuits: a start-up circuit configured to connect the separate power source to the electrical equipment, and a start-up circuit configured to start operation of the TNP system. Certain implementations refer to such an arrangement as a two-stage start-up.

[0094] Two-step startup FIG. 5 illustrates a block diagram of a TNP system 500 configured to isolate the electronic circuitry from the power source according to some embodiments. The system 500 includes a power source 12E, an electronic circuitry 30, and a negative pressure source 12C. The electronic circuitry 30 includes a controller 12A, an isolation circuitry 32, an operating switch 33, and one or more capacitors 35. As described herein, activation of the operating switch 33 can activate the controller 12A and activate charging of one or more capacitors 35, which can store energy and provide energy (e.g., current) to the negative pressure source 12C. FIG. 5 illustrates how the isolation circuitry 32 can prevent the power source 12E from electrically coupling to the remainder of the electronic circuitry 30 according to some embodiments.

[0095] The power source 12E may include one or more power sources, such as batteries (which may be boosted, AC and / or DC), that provide power to one or more components of a TNP device, such as the TNP device 11, including the electronic circuitry 30 and the negative pressure source 12C. The power source 12E may provide current and voltage to, for example, the isolation circuitry 32. The voltage output by the power source 12E may include one or more of approximately 3V, 6V, 27V, or the like, in some implementations. The power source 12E and / or the electronic circuitry 30 may additionally include circuitry, such as a boost converter, to control the provided current and voltage. In some implementations, power conversion is performed between one or more capacitors 35 and the negative pressure source 12C. For example, the boost converter may increase the output of the power source 12E to charge one or more capacitors 35 and / or power the negative pressure source. In some cases, the boost converter may not boost the output of the power source, but instead control a therapy device and / or control one or more sensors of the system. In such a case, the boost converter can act as a secondary power controller (in addition to the primary controller) that can turn on / off a negative pressure source and / or another therapy device, such as an ultrasound generator, an oxygen concentrator, a cold plasma generator, etc.

[0096] The isolation circuit 32 allows the power source 12E to be isolated from electrical coupling with the rest of the electronic circuitry 30. In some embodiments, the isolation circuit 32 operates in two or more states. In a first "off" state, the isolation circuit 32 operates as an open circuit, which prevents the output of the power source 12E from being provided to other components of the electronic circuitry 30. In this state, the one or more capacitors 35 are unable to store electricity, thereby preventing accidental overheating, sparks, and / or fire during sterilization, even if the operating switch 33 is inadvertently activated. In a second "on" state, the isolation circuit 32 allows the output of the power source 12E to be provided to other components of the electronic circuitry 30, thereby allowing the one or more capacitors 35 to store electrical energy.

[0097] When the isolation circuit 32 is in a first "off" state, the isolation circuit 32 does not provide power from the power source 12E to the negative pressure source 12C, whereas when the isolation circuit 32 is in a second "on" state, depending on the state of the operation switch 33, operating power may be provided to the negative pressure source 12C to provide negative pressure wound therapy.

[0098] 5, the operation switch 33 is electrically connected to and located between the power source 12E and the negative pressure source 12C. The operation switch 33 may be operable in two or more states. In a first, "off" state, the operation switch 33 prevents operation of the negative pressure source 12C. In a second, "on" state, the operation switch 33 allows operation of the negative pressure source 12C. In some cases, the operation switch 33 may be located closer to the power source 12E than the isolation circuit 32, or further away.

[0099] In some embodiments, switching the state of the isolation circuit 32 to an "on" state (e.g., activating the isolation circuit 32) may indicate step 1 of activation. Switching the state of the operation switch 33 to an "on" state (e.g., activating the operation switch 33) may indicate step 2 of activation. Together, the steps may form a two-stage activation that provides safe sterilization of the integrated TNP system. With respect to step 1, when the isolation circuit 32 is in a first "off" state, activation of the operation switch 33 does not provide power to one or more of the other components because the remaining components of the electronic circuit 30 do not receive or see power. On the other hand, when the isolation circuit 32 is in a second "on" state, each state of the operation switch 33 activates (operation switch 33 "on") or deactivates (operation switch 33 "off") the operation of one or more of the controllers 12A, one or more capacitors, or the negative pressure source 12C. Those skilled in the art will recognize various alternative circuit configurations that may implement the two-stage activation as described in some implementations. For example, in some cases, the controller 12A can receive power from the power source 12E regardless of the state of the isolation circuit. The controller 12A can operate in a low power mode until the isolation circuit 32 transitions to an "on" state. When the isolation circuit 32 is in an "off" state, no power is provided to the boost converter described herein.

[0100] In some implementations, the controller 12A controls the operation of the negative pressure source 12C by outputting one or more control signals to one or more inputs of a drive circuit (not shown) that is electrically coupled to the negative pressure source 12C. In some embodiments, the controller 12A can vary the pulse width modulation (PWM) of the output control signal to adjust the current and voltage supplied by the drive circuit to the negative pressure source 12C.

[0101] Although one or more capacitors 35 are illustrated as exemplary components capable of storing electrical energy, it should be understood that capacitors are not the only type of components capable of storing electrical energy. Other energy storage components may alternatively or additionally be used, depending on possible circuit variations embodying the ideas of the present disclosure. In some cases, one or more capacitors 35 are arranged to hide fluctuations in current flow, correct power factors, provide AC coupling or isolation, suppress noise and spikes, condition the circuit, and / or other purpose capacitors are used in the circuit.

[0102] 6A and 6B illustrate circuit diagrams of electronic circuits of a negative pressure wound therapy system, according to some embodiments. Referring to FIG. 6A, as shown in FIG. 6B (which may be the same or similar to the isolation circuit 32 of FIG. 5), the circuit 600A includes a power source 610 and terminals or pins LAT_IN 612 (representing a "latch in circuit pin") and LAT_OUT 614 (representing a "latch out circuit pin") for connecting the isolation circuit 600B. The power source 610 (represented as two batteries cell 1 and cell 2) is connected to pin 612.

[0103] In some embodiments, when the isolation circuit 600B is in an on (or activated) state, current flows between pins 612 and 614. In turn, when an operating switch (not shown) is activated (or in an "on" state), switch 620 (shown as a transistor) turns on, allowing one or more capacitors (not shown) to be charged from the power source 610. When the isolation circuit 600B is in an "off" (or deactivated) state, no current flows between pins 612 and 614. Regardless of the state of the operating switch, when the isolation circuit 600B is deactivated, switch 620 does not turn on and the one or more capacitors do not charge. As described herein, this operation reduces the risk of, for example, energy stored by one or more capacitors, overheating, spark generation, and / or ignition of sterilizing gas during sterilization of the entire integrated TNP system.

[0104] FIG. 6B provides an isolation circuit 600B according to some embodiments. The circuit 600B may be connected between pins LAT_IN 612 and LAT_OUT 614 of FIG. 6A. The circuit 600B includes an activation switch or another mechanism 630, such as a pull tab, to activate the circuit. When the activation switch 630 is not activated (the pull tab is not pulled), the switches 640 and 650 are closed or off to prevent current from flowing between the pins 612 and 614. When the activation switch 630 is activated (e.g., pulled as described herein), an electrical path is provided (e.g., to ground) to allow current to flow. This activates the switch 650, allowing current to flow between the pins 612 and 614. As shown, the switch 650 may be a PFET transistor (e.g., a PMOS transistor) that is activated (e.g., becomes conductive) when current flows from the pin 612 (connected to the power source 610 shown in FIG. 6A) through the electrical path provided by the activated activation switch 630. The current can activate the switch 650 (e.g., a PFET transistor), which can provide an electrical path for the current between the pin 612 and the pin 614. The activation of the switch 650 can then activate (e.g., become conductive) the switch 640, which as illustrated can be an NFET transistor (e.g., an NMOS transistor). When the switch 650 is activated, current can flow between the pins 612 and 614, thereby allowing the switch 620 to turn on as described herein. In some cases, when the isolation circuit 600B transitions to an on state, power is provided to the boost converter. For example, this can charge an energy storage component, such as one or more capacitors, which can power a negative pressure source.

[0105] In some embodiments, the isolation circuit 600B is a self-latching circuit. The circuit 600B can operate such that once the activation switch 630 is activated, the circuit 600B remains activated and allows current to flow between the pins 612 and 614 even if the activation switch 630 is subsequently deactivated. In such a case, once the switches 650 and 640 are activated and power continues to be applied to the pin 612, the circuit 600B is not configured to be reset such that the circuit continues to operate in the "on" state. Power can be continuously applied to the pin 612 by a permanently connected battery or another power source. In some cases, the latching is provided by activating the switch 640 as described herein. When initially activated, the switch 640 (e.g., an NFET transistor) can remain activated regardless of the state of the activation switch 630. The switch 640 can provide an electrical path for the current (e.g., ground) required to maintain the switch 650 even if the activation switch 630 is deactivated and does not provide an electrical path for the current. For example, switch 640 may remain activated because the NFET transistor source is connected to ground, thereby keeping the transistor in an active state when a voltage is applied to its gate from pin 612 .

[0106] In a particular implementation, when the isolation circuit 600B provides an electrical connection between the pins 612 and 614, a user of the TNP system can activate an operating switch (such as switch 32 in FIG. 5 ) to wake up the controller 12A to turn on the switch 620, thereby charging one or more capacitors (such as one or more capacitors 35 in FIG. 5 ). Those skilled in the art will readily appreciate that the selection of PMOS and NMOS transistor switches and other circuit elements may have some variances. Also, as described herein, the pull tab 630 may be replaced with other activation mechanisms, such as one or more buttons. In some cases, the activation mechanism 630 may be a power source, such as a secondary power source that may be added to the power source described herein (which may function as a primary power source). In some cases, the secondary power source may have a larger capacity than the main power source. Connecting or plugging in a secondary power source may increase the risk of overheating, sparking, and / or ignition of the sterilizing gas during sterilization of the TNP device.

[0107] In some cases, the status of the isolation circuit 600B may be communicated to a user using one or more indicators (e.g., one or more indicators 266). For example, the deactivated status of the isolation circuit may be indicated to a user, which may prompt a user wishing to begin providing negative pressure to activate the isolation circuit, for example, by pulling a pull tab, pressing a button, activating a switch, connecting or plugging into a secondary power source. As another example, the activated status of the isolation circuit may be indicated to a user, which may indicate to the user that activation was successful.

[0108] FIG. 7 illustrates a back view of a printed circuit board (PCB) 700 configured to implement a two-stage activation, according to some embodiments. The PCB 700 includes an activation switch 715 that can be operated by a pull tab, and an operation switch 720. The switch 715 includes conductive "fingers" or paths that are not electrically connected when the isolation circuit is in the "off" state. A pull tab 810 (FIG. 8A) may be attached to the opposite side of the PCB 700, and when pulled, the two sets of fingers make electrical contact with each other, placing the isolation circuit in the "on" state. For example, the fingers may be pressed toward each other, electrically connected as described in the connection of FIG. 9C, etc. The multiple fingers of the switch 715 can ensure that an electrical connection is made when the pull tab 810 is pulled. This type of structure may be used in conjunction with step 1 activation (e.g., activation of the isolation circuit 32 of FIG. 5) after sterilization is completed. FIG. 7 illustrates a switch 715 that cannot be deactivated after activation because the conductive fingers remain electrically connected after the pull tab 810 is pulled by a user.

[0109] It should be noted that while the illustrated switch 715 is configured for irreversible actuation (e.g., the fingers cannot simply be depressurized so that they are not electrically connected), reversible actuation mechanisms may also be used, as described herein. Additionally, other types of actuation / switching mechanisms may be used based on various engineering or aesthetic considerations.

[0110] PCB 700 also illustrates the backside of an operating switch 720 (labeled as 33 in FIG. 33) configured for step 2 activation. Its front side may be a dome switch 820 as shown in FIG. 8B. Pressing the dome switch activates or deactivates step 2 of the two-stage activation.

[0111] 8A and 8B respectively illustrate front views of a two-stage activation PCB before and after the pull tab has been pulled, according to some embodiments. In the illustrated embodiment, the pull tab 810 is removed to expose the dome switch 820, thereby reducing the possibility that two-stage activation may be performed in reverse. As illustrated in FIG. 8B, removal of the pull tab 810 removes the insulating material 830 from the surface of the switch 715 (FIG. 7) so that an electrical connection is made between the fingers of the switch. Also illustrated are indicators 842 and 844 that can indicate the operational state of the TNP device. The pull tab 810 includes a pattern 850 that instructs the user to pull the tab in a particular direction (e.g., to the left in the illustrated embodiment).

[0112] 9A and 9B illustrate various designs of shapes and patterns of pull tabs, such as pull tab 810, according to some embodiments.

[0113] FIG. 9C illustrates a pull tab 910, according to some embodiments. The pull tab 910 can be used with any of the activation switch embodiments described herein, such as switch 715. The pull tab 910 includes a region 930 configured to contact an activation switch, such as switch 715, when the pull tab is positioned on a PCB (see, e.g., FIGS. 7 and 8A). The region 930 can include a conductive material applied to the conductive path of the activation switch that activates the switch when the pull tab 910 is pulled. For example, with reference to FIG. 7, the region 930 can be positioned in contact with the fingers of switch 715. When the pull tab 910 is removed, a conductive material is applied to the fingers, bringing the two sets of fingers into electrical contact with each other. In this case, the isolation circuit is in an "on" state.

[0114] 9C, the pull tab 910 also includes a pattern 950 that instructs the user to pull to the left. Additionally, the pull tab 910 includes an area 942 that may be coated with an adhesive material to prevent inadvertent activation by keeping the pull tab 910 attached to the PCB prior to being pulled by a user (see, e.g., FIGS. 8A-8B).

[0115] In some embodiments, the conductive material in region 930 includes silver, which may be applied to region 930 as a silver ink or deposited in region 930. When the pull tab is pulled by a user, the silver ink from region 930 may be applied across the activation switch to complete step 1 of activation. For example, for switch 715 illustrated in FIG. 7, applying silver ink from region 930 to the conductive fingers of the switch may create one or more short circuits across the fingers such that switch 715 is turned on. In some implementations, a single or multiple layers of silver ink may be printed in region 930.

[0116] In certain embodiments, in addition to or instead of silver, other conductive materials, formulations, or compounds may be deposited in region 930. These may include carbon, gold, palladium, etc. In some cases, it may be advantageous to use materials, formulations, or compounds that do not oxidize easily.

[0117] In certain embodiments, the pull tab 910 may be made of plastic. The conductive material in the region 930 may be applied to the plastic material by any suitable technique, such as screen printing, inject printing, sputtering, electrochemical deposition, plating, thin film bonding, or the like.

[0118] In some implementations, during step 1 of activation, the activation switch can be turned off (instead of on). In such a case, the activation switch can be aborted by pulling a pull tab. Although a pull tab is described above, additional or alternative forces can be applied to complete step 1 of activation. Such forces may include pushing, depression, etc.

[0119] FIG. 10 illustrates a front view of a two-stage activation PCB, according to some embodiments. Instead of a pull tab, a dome switch 1010 is used for step 1 activation and another dome switch 1020 is used for step 2 activation. In some embodiments, step 1 activation using switch 1010 is timed, so step 2 activation using switch 1020 must be pressed within a certain time period to activate switch 1010 for step 1. In some embodiments, either or both steps may require pressing and holding dome switch 1010 and / or 1020 for an extended period of time for activation. In some embodiments, the two steps may be merged into one switch that distinguishes the activation steps based on the duration of the press. For example, a long press of the switch may perform step 1 activation, followed by a short press to perform step 2 activation. One skilled in the art will appreciate that various types of switches with different operating mechanisms may be used for two-stage activation.

[0120] Electronic Assembly Incorporated Within Wound Dressing - Patent application FIG. 11 illustrates a wound dressing layer incorporating electronic components within the wound dressing, according to some embodiments. The dressing layers and components of FIG. 11 may be similar to the dressing layers and components in FIGS. 1A-1C or any other embodiment described herein. FIG. 11 illustrates a wound dressing having a wound contact layer 810 configured to contact a wound. The wound contact layer 810 may be of a similar material and have a similar function as the wound contact layer described with reference to FIGS. 1A-1C. A transmission or spacer layer 811 is provided on top of the wound contact layer. The transmission or spacer layer 811 may be of a similar material and have a similar function as the transmission or spacer layer described with reference to FIGS. 1A-1C. The transmission layer 811 may assist in delivering and distributing negative pressure over the wound site.

[0121] A first layer of apertured absorbent material 851 may be provided over the transmissive layer 811. The first apertured absorbent layer 851 may include one or more apertures 829. In some embodiments, the apertures 829 may be sized and shaped to fit an electronic assembly and / or electronic unit therein. The first apertured absorbent layer 851 may be sized and shaped to fit the dimensions of the electronics area 861 and does not extend into the absorbent area 860. In some embodiments, the apertures 829 may be sized and shaped to fit an electronic assembly as described herein.

[0122] An absorbent layer 822 with a second opening may be provided over the first absorbent layer 851. In some embodiments, the second absorbent layer 822 includes one or more openings 828. The second absorbent layer 822 may be sized and shaped to accommodate the dimensions of the electronics area 861 and the absorbent area 860. In some embodiments, the opening 828 may be sized and shaped to accommodate an electronic assembly described herein. The first absorbent layer 851 and the second absorbent layer 822 may be of similar materials and have similar functionality as the absorbent layers described with reference to Figures 1A-1C.

[0123] A cover or backing layer 813 may be disposed over the absorbent material 822. The cover or backing layer 813 may be of a similar material and may have a similar function as the cover or backing layers described with reference to Figures 1A-1C. The cover layer 813 may form a seal with the wound contact layer 810 in a peripheral area surrounding the absorbent layers 822 and 851 and the transmission layer 811. In some embodiments, the cover layer 813 may be a sheet of flexible material that forms and molds around the dressing components when the dressing components are applied to the wound. In other embodiments, as shown in Figure 11, the cover layer 813 may be a preformed or premolded material to fit around the dressing components. As used herein, the terms cover layer and backing layer may be used interchangeably to refer to layers of material within the dressing that are configured to cover the dressing layer.

[0124] In some embodiments, the covering or backing layer 813 may include an opening 872. The opening 372 may be positioned over at least a portion of the opening 828 in the absorbent layer 822 to allow access to and fluid communication with at least a portion of the underlying absorbent layers 822 and 851, the transmission layer 811, and the wound contact layer 810.

[0125] The electronic assembly may be positioned in the openings 828, 829, 872 of the first absorbent material 851 and the second absorbent material 822 and the cover layer 813. The electronic assembly may include a pump, a power source, and a printed circuit board as described herein.

[0126] Prior to use, the dressing may include one or more delivery layers 846 adhered to the bottom surface of the wound contact layer. The delivery layer 846 may cover the adhesive or openings on the bottom surface of the wound contact layer 810. In some embodiments, the delivery layer 846 may provide support to the dressing and aid in sterilization and proper placement of the dressing on the patient's wound and skin. The delivery layer 846 may include a handle that a user may use to separate the delivery layer 846 from the wound contact layer 810 before applying the dressing to the patient's wound and skin.

[0127] 12A illustrates a wound dressing incorporating an electronic assembly 900 within a wound dressing layer 990, according to some embodiments. The electronic assembly 900 may be provided within an opening 872 in the cover layer and openings 829 and 828 in the first and second absorbent layers. In some embodiments, the electronic assembly 900 may be sealed to the periphery of the opening 872 in the cover layer.

[0128] The electronic assembly 900 may include a pump inlet protection feature extending from and sealed to the film, as described herein. The electronic assembly 900 may be positioned within the openings 872, 829, 828 in the cover layer and absorbent layer, as shown in FIG. 12A. In some embodiments, the periphery of the electronic assembly 900 may be sealed to the top surface of the periphery of the opening 872 in the cover layer, as shown in FIG. 12A. In some embodiments, the electronic assembly 900 is sealed to the cover layer 813 using a sealant gasket, adhesive, heat welding, adhesive bonding, ultrasonic welding, RF welding, or any other attachment or bonding technique. In some embodiments, the electronic assembly 900 may be permanently sealed to the cover layer 813 and cannot be removed from the cover layer without destroying the covering material.

[0129] In some embodiments, the electronic assembly 900 is available in a single enclosure and may be disposed of together with the enclosure, hi other embodiments, the electronic assembly 900 is available in a series of enclosures.

[0130] 12B illustrates a cross-sectional layout of material layers of a wound dressing incorporating an electronic assembly within the dressing, according to some embodiments. The dressing includes multiple material layers and an electronic assembly 900. The wound dressing may include an electronics area 961 including electronics and an absorbent area or dressing area 960 intended to be applied to a wound, as described with reference to FIGS. 1A-1C.

[0131] As described herein, one or more layers of material may extend over both the electronics area 961 and the dressing area 960. The dressing may include a wound contact layer 810, a transmission layer 811, absorbent layers 822 and 851, and a cover or backing layer 813, as illustrated in FIG. 12B. The absorbent layers 822 and 851 and the cover layer 813 may include recesses or cutouts for receiving components of the electronic assembly 900 described with reference to FIG. 12A. In some embodiments, the absorbent layer 851 with the small opening may be positioned above the absorbent layer 822 with the large opening. In other embodiments, the absorbent layer 851 with the small opening may be positioned below the absorbent layer 922 with the large opening, as shown in FIGS. 9A and 9B.

[0132] In some embodiments, the electronic assembly 900 may be inserted and affixed to the dressing layer, and the wound-facing underside of the film surrounding the electronic assembly may be sealed directly to the top surface of the cover layer 813 of the dressing, as shown in FIG.

[0133] Prior to use, the dressing may include a delivery layer 846 adhered to a bottom surface of the wound contact layer 810. The delivery layer 846 may cover adhesive or openings on the bottom surface of the wound contact layer 810. In some embodiments, the delivery layer 846 may provide support to the dressing and aid in sterilization and proper placement of the dressing on the patient's wound and skin. The delivery layer 846 may include a handle that a user may use to separate the delivery layer 846 from the wound contact layer 810 before applying the dressing to the patient's wound and skin.

[0134] 13 illustrates a wound dressing incorporating an electronic assembly within the dressing layer, according to some embodiments. As shown in FIG. 13, the wound dressing comprises an absorbent area 1060 and an electronics area 1061. An electronics assembly 1050 can be incorporated into the electronics area 1061 of the dressing. As described in more detail with reference to FIG. 12A and FIG. 12B, the periphery of the electronics assembly 1050 can be sealed around an opening (not shown) in the cover layer 1013.

[0135] FIG. 13 illustrates a negative pressure indicator 1091 in the wound dressing that indicates when components in the wound dressing 1000 are under negative pressure. As shown in FIG. 13, the wound dressing can include an absorbent area 1060 adjacent to or offset from an electronics area 1061. In some embodiments, the absorbent area 1060 can include an absorbent material that absorbs and retains liquid and / or wound exudate from the wound. In some embodiments, the electronics area 1061 can include electronics assemblies and / or electronics components described herein. The negative pressure indicator can be a mechanical indicator. In some embodiments, the negative pressure indicator can be an indicator that does not require a direct line of sight from the patient. For example, the negative pressure indicator can be an indicator that can be touched or felt by the patient or user. The negative pressure indicator 1091 can be a gap or cutout in the absorbent material of the dressing. When negative pressure is applied underneath the cover layer, the dressing will tighten and the cover layer will compress as it is drawn into gaps or cutouts in the absorbent material, indicating that negative pressure is being applied.

[0136] FIG. 13 illustrates a top view of an embodiment of a wound dressing layer incorporating an electronics assembly within the dressing. In some embodiments, the plate of the electronics assembly 1050 can include electronics label features and text. In other embodiments, the electronics label can be fixed or adhered to the plate of the electronics assembly 1050. In some embodiments, the plate and / or label can include one or more holes or openings located over or in communication with the switches, visual indicators, and / or pump exhaust mechanism vents on the flexible circuit board. In some embodiments, the plate and / or label can include a transparent or semi-transparent visual indicator portion 1044, which allows light from the visual indicator on the flexible circuit board to be visible. Additionally, as shown in FIG. 13, the transparent or semi-transparent visual indicator portion 1044 of the plate and / or label can include visual symbols or text to communicate the status of the dressing or electronics. In some embodiments, the plate and / or label can include embossed features for the switch cover 1043. In some embodiments, the embossed features of the switch cover 1043 may prevent accidental activation or deactivation of the device, as described herein. In some embodiments, the switch or switch cover 1043 may include a tab on the switch, which may be a pull tab as described herein. In some embodiments, the plate and / or label may include an opening or hole 1042 in fluid communication with a vent in the exhaust mechanism of the pump to allow air to escape being exhausted from the pump.

[0137] In some embodiments, various shapes and sizes of wound dressings that may incorporate electronic assemblies are illustrated. Wound dressings with embedded electronic assemblies may be of any shape or size to accommodate various types of wounds and conform to the shape and contours of a patient's body. For example, wound dressings with embedded electronics may have a rectangular shape, a rounded rectangular shape, a square shape, a T-shape, or any other shape or design. The wound dressing may have a longitudinal length parallel to a longitudinal axis that extends the entire length of the dressing through the electronics area and the absorbent area. The absorbent area may have a longitudinal axis that extends parallel to the longitudinal axis of the dressing. In some embodiments, the dressing has a length parallel to the longitudinal axis that is greater than its width. The electronic assembly may have a longitudinal axis perpendicular to the longitudinal axis of the absorbent area. In some embodiments, the electronic assembly has a length parallel to the longitudinal axis that is greater than its width. In some embodiments, the absorbent area of ​​the wound dressing may have an elongated rectangular shape with the total length of the absorbent area being greater than the width of the absorbent area. In some embodiments, the absorbent area of ​​the wound dressing may have a square shape with the total length of the absorbent area being substantially equal to or equal to the width of the absorbent area. In some embodiments, the wound dressing with embedded electronics described herein may have a rectangular or rounded rectangular shape as illustrated with reference to Figures 1A-1C. In other embodiments, the wound dressing with embedded electronics described herein may have a T-shape as illustrated with reference to Figures 11-13.

[0138] Other Variations Any values ​​of thresholds, limits, periods, etc. provided herein are not intended to be absolute and may therefore be approximate. Furthermore, any thresholds, limits, periods, etc. provided herein may be fixed or varied, either automatically or by a user. Furthermore, as used herein, terms expressing a relative degree, such as exceeding, over, under, etc., in relation to a reference value are intended to encompass equality to the reference value. For example, exceeding a positive reference value may encompass being equal to or greater than the reference value. Moreover, as used herein, terms expressing a relative degree, such as exceeding, over, under, etc., in relation to a reference value are intended to encompass the inverse of the disclosed relationship, such as below, under, over, etc., in relation to the reference value. Also, although various process blocks may be described with respect to determining whether a value reaches or does not reach a particular threshold, the blocks may be similarly interpreted with respect to, for example, whether a value is (i) below or over a threshold, or (ii) meeting or not meeting a threshold.

[0139] It is to be understood that a property, material, feature, or group described in connection with a particular aspect, embodiment, or example may be applied to any other aspect, embodiment, or example described herein, unless incompatible therewith. All features disclosed in this specification (including any accompanying claims, abstract, and drawings), or all steps of any method or process similarly disclosed, may be combined in any combination, except combinations in which at least some of such features or steps are mutually exclusive. Protection of the invention is not limited to the details of any of the preceding embodiments. Protection extends to any novel, or any novel combination of features disclosed in this specification (including any accompanying claims, abstract, and drawings), and / or to any novel, or any novel combination of steps of any method or process similarly disclosed.

[0140] Although specific embodiments have been described, these embodiments are presented merely as examples and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in various other forms. Furthermore, various omissions, substitutions, and modifications may be made in the methods and systems described herein. Those skilled in the art will recognize that in some embodiments, the actual steps performed in the illustrated or disclosed processes may differ from those shown in the figures. In some embodiments, certain steps of the steps described above may be removed and others may be added. For example, the actual steps or order of steps performed in the disclosed processes may differ from those shown in the figures. In some embodiments, certain steps of the steps described above may be removed and others may be added. For example, the various components shown in the figures may be implemented as software or firmware on a processor, controller, ASIC, FPGA, or dedicated hardware. Hardware components such as processors, ASICs, FPGAs, etc. may include logic circuits. Furthermore, the features and characteristics of the specific embodiments disclosed above may be combined in various ways to form further embodiments, all of which will fall within the scope of the present disclosure.

[0141] The user interface screens shown and described herein may include additional or alternative components. These components may include menus, lists, buttons, text boxes, labels, radio buttons, scroll bars, sliders, check boxes, combo boxes, status bars, dialog boxes, windows, etc. The user interface screens may include additional or alternative information. The components may be arranged, grouped, and labeled in any suitable order.

[0142] Although the present disclosure includes specific embodiments, examples, and applications, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments or uses and obvious modifications and equivalents thereof, including embodiments that do not provide all of the features and advantages described herein. Thus, the scope of the present disclosure is not intended to be limited by the specific disclosure of preferred embodiments herein, but may be defined by the claims presented herein or hereafter.

[0143] Conditional language such as "can," "could," "might," or "may," unless specifically stated otherwise or interpreted otherwise within the context in which it is used, is typically intended to convey that certain embodiments include certain features, elements, or steps, while other embodiments do not. Thus, such conditional language is not necessarily intended to suggest that the features, elements, or steps are in any way required by one or more embodiments, or that one or more embodiments necessarily include logic for determining, with or without user input or instruction, whether those features, elements, or steps are included in or should be performed in any particular embodiment. Terms such as "comprising," "including," and "having" are synonymous and are used in an inclusive, non-limiting manner and do not exclude additional elements, features, acts, operations, and the like. The term "or" is also used in an inclusive sense (not an exclusive sense), e.g., when used to connect a list of elements, it means one, some, or all of the elements in the list. Further, the term "each" as used herein, in addition to having its ordinary meaning, can also refer to any subset of the series of elements to which the term "each" is applied.

[0144] Conjunctive phrases such as "at least one of X, Y, and Z," unless specifically stated otherwise, are to be construed in conjunction with the context in which they are generally used to convey that an item, term, etc. can be either X, Y, or Z. Thus, such conjunctive phrases are not generally intended to suggest that a particular embodiment requires that it includes at least one of X, at least one of Y, and at least one of Z.

[0145] As used herein, degree-expressing phrases such as "approximately," "about," "generally," and "substantially" refer to a value, amount, or characteristic that is close to a given value, amount, or characteristic that still performs a desired function or produces a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to an amount that is within 10%, 5%, 1%, 0.1%, and 0.01% of a given amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to a value, amount, or characteristic that deviates from exactly parallel by 15 degrees or less, 10 degrees or less, 5 degrees or less, 3 degrees or less, 1 degree or less, or 0.1 degrees or less.

[0146] The scope of the disclosure is not intended to be limited by the specific disclosure of preferred embodiments in this section or elsewhere herein, but may be defined by the claims presented in this section or elsewhere herein or presented hereafter. The claim language should be interpreted broadly based on the language used in the claims, and not limited to the examples described herein or during the prosecution of this application, which examples should be interpreted as non-exclusive. [Additional note 1] 1. A negative pressure wound therapy system comprising: a wound dressing configured to be placed over a wound of a patient; a negative pressure source disposed on or within the dressing and configured to provide negative pressure to the wound; an electronic circuit disposed on or within the covering, a controller configured to operate the negative pressure source; a power source configured to provide power to the electronic circuitry; and an isolation circuit in electrical communication with the power source and the controller, the isolation circuit configured to operate in a first state in which the isolation circuit prevents application of power to the controller and in a second state in which the isolation circuit allows application of power to the controller, the isolation circuit comprising an activation switch configured to be activated to cause the isolation circuit to operate in the second state. [Additional note 2] 2. The system of claim 1, wherein the activation switch is activated by a tab configured to be removed by a user, and activation of the activation switch causes the isolation circuit to operate in the second state. [Additional note 3] 3. The system of claim 2, wherein the activation switch is configured to remain activated even after removal of the tab. [Additional note 4] 4. The system of any of claims 2 or 3, wherein the tab comprises a conductive material configured to be applied to the activation switch to activate the activation switch. [Additional note 5] 5. The system of claim 4, wherein the conductive material includes silver ink deposited in an area of ​​the tab, the area configured to contact the activation switch during activation. [Additional note 6] The system according to any one of claims 1 to 5, wherein the activation switch includes a button. [Additional note 7] The system described in any one of appendix 1 to 6, wherein the electronic circuit further comprises at least one capacitor configured to store energy supplied by the power source and configured to provide the stored energy to the negative pressure source. [Additional note 8] 8. The system of claim 7, wherein the isolation circuit in the first state of operation is further configured to prevent charging of the at least one capacitor. [Additional note 9] The system described in any one of appendix 1 to 8, wherein the electronic circuit further comprises an operation switch configured to start and pause the provision of negative pressure by the negative pressure source. [Additional Note 10] The system of claim 9, wherein the electronic circuit is configured to not activate the negative pressure source to provide negative pressure when the isolation circuit is in the first state and the operation switch is activated. [Additional Note 11] 11. The system according to any one of claims 1 to 10, wherein the isolation circuit includes a latch circuit. [Additional Note 12] 12. The system of claim 11, wherein the latch circuit is configured to maintain the isolation circuit in the second state in response to an initial activation of the activation switch. [Additional Note 13] The latch circuit, in response to the deactivation of the activation switch after the initial activation, 13. The system of claim 12, configured to maintain the isolation circuit in the second state. [Additional Note 14] 14. The system according to any one of claims 1 to 13, wherein the power supply is non-removable. [Additional Note 15] 15. The method according to any one of claims 1 to 14, wherein the negative pressure source comprises a micropump. [Additional Note 16] The system described in any one of claims 1 to 15, wherein the electronic circuit is configured so that the isolation circuit is in the first state and the negative pressure source is not activated to provide negative pressure. [Additional Note 17] 17. The system of claim 1, further comprising an indicator configured to provide at least one of an indication that the activation switch is not activated or an indication that the activation switch is activated. [Additional Note 18] 18. The system of claim 1, wherein the controller comprises a boost converter configured to power the negative pressure source, and the system includes a primary controller configured to be powered by the power source when the isolation circuit is in the first or second state. [Additional Note 19] 20. The system of claim 18, further comprising at least one energy storage element configured to store energy provided by the boost converter and power the negative pressure source with the stored energy. [Additional Note 20] 1. A method of operating a negative pressure wound therapy device comprising: a wound dressing; a negative pressure source disposed on or within the dressing; and electronic circuitry disposed on or within the wound dressing and configured to operate the negative pressure source, comprising: activating an activation switch configured to operate the electronic circuit in a first state in which power is also applied to a controller of the electronic circuit, the electronic circuit having been sterilized with ethylene oxide (EtO) while operating in a second state in which power is not applied to the controller; activating a negative pressure source to provide negative pressure to the wound dressing. [Additional Note 21] 21. The method of claim 20, further comprising activating the activation switch by removing a tab. [Additional Note 22] 21. The method of claim 20, wherein the activation switch comprises a button, and activating the activation switch comprises pressing the button. [Additional Note 23] 23. The method of any one of claims 20 to 22, wherein activating the negative pressure source comprises activating an operating switch configured to activate and deactivate the negative pressure source. [Additional note 24] 1. A method of operating a negative pressure wound therapy device comprising: a wound dressing; a negative pressure source disposed on or within the dressing; and electronic circuitry disposed on or within the wound dressing and configured to operate the negative pressure source, comprising: maintaining an isolation circuit of the electronic circuit in an inoperative state in which power is not provided to an energy storage component of the electronic circuit configured to provide power to the negative pressure source, wherein the device is sterilized when the isolation circuit is in the inoperative state; transitioning the isolation circuit to an active state in which power is provided to the energy storage component in response to activation of an activation switch of the electronic circuit; activating the negative pressure source when the isolation circuit is in the second state. [Additional note 25] 25. The method of claim 24, wherein the device is sterilized with ethylene oxide (EtO). [Additional note 26] 26. The method according to any one of claims 24 to 25, further comprising maintaining the isolation circuit in the activated state in response to an initial activation of the activation switch. [Additional note 27] 27. The method according to any one of claims 24 to 26, wherein activating the activation switch comprises at least one of pulling a tab, pressing a button, or connecting a secondary power source. [Additional note 28] 28. The method according to any one of claims 24 to 27, wherein activating the negative pressure source comprises activating the negative pressure source in response to activation of the operation switch. [Additional note 29] 30. The method of claim 28, further comprising shutting down the negative pressure source in response to deactivation of the operating switch. [Additional note 30] 30. The method according to any one of claims 28 to 29, further comprising not activating the negative pressure source in response to the activation of the operation switch when the isolation circuit is in the inactive state. [Additional note 31] The method according to any one of claims 24 to 30, further comprising displaying at least one of the following: that the activation switch has not been activated; and that the activation switch has been activated. [Additional note 32] 32. The method of any one of clauses 24 to 31, wherein the energy storage component comprises a capacitor.

Claims

1. - a wound dressing configured to be placed over a wound on a patient; - a negative pressure source disposed on or within the dressing, the negative pressure source configured to provide negative pressure to the wound; an electronic circuit disposed on or within the covering, - a controller configured to operate said negative pressure source; a power source configured to supply power to said electronic circuit; an isolation circuit electrically coupled to the power source and the controller, the isolation circuit configured to operate in a first state in which the isolation circuit prevents application of power to the controller and a second state in which the isolation circuit allows application of power to the controller, the isolation circuit comprising an activation switch configured to be activated to cause the isolation circuit to operate in the second state; and an electronic circuit comprising: the electronic circuit further comprising an operation switch configured to activate and pause the provision of negative pressure by the negative pressure source; the activation switch is activated by pulling a tab configured to be removed by a user, activation of the activation switch causing the isolation circuit to operate in the second state; the tab includes a conductive material configured to be removed from the tab when the tab is removed by the user and applied to the activation switch to activate the activation switch, the conductive material including silver ink deposited in an area of ​​the tab, the area configured to contact the activation switch during activation. Negative pressure wound therapy system.

2. The system of claim 1 , wherein the activation switch is configured to remain activated after removal of the tab.

3. 3. The system of claim 1 or 2, wherein the operating switch is visually obscured by the tab when the tab is attached to the system.

4. The system of any one of claims 1 to 3, wherein the electronic circuit further comprises at least one capacitor configured to store energy supplied by the power source and configured to provide the stored energy to the negative pressure source.

5. 5. The system of claim 4, wherein the isolation circuit in the first state of operation is further configured to prevent charging of at least one of the capacitors.

6. 2. The system of claim 1, wherein the electronic circuit is configured to not activate the negative pressure source to provide negative pressure when the isolation circuit is in the first state and the operation switch is activated.

7. The system of any one of claims 1 to 6, wherein the isolation circuit comprises a latch circuit.

8. the latch circuit is configured to maintain the isolation circuit in the second state in response to an initial activation of the activation switch; 8. The system of claim 7, optionally wherein the latch circuit is configured to maintain the isolation circuit in the second state in response to deactivation of the activation switch after the initial activation.

9. The system of any one of claims 1 to 8, wherein the power source is non-removable.

10. The system of any one of claims 1 to 9, wherein the negative pressure source comprises a micropump.

11. The system of any one of claims 1 to 10, wherein the electronic circuit is configured not to activate the negative pressure source to provide negative pressure when the isolation circuit is in the first state.

12. 12. The system of claim 1, further comprising an indicator configured to provide at least one of an indication that the activation switch has not been activated and an indication that the activation switch has been activated.

13. 13. The system of claim 1, wherein the controller comprises a boost converter configured to power the negative pressure source, and the system includes a secondary power controller configured to be powered by the power source when the isolation circuit is in the first or second state.

14. 14. The system of claim 13, further comprising at least one energy storage element configured to store energy provided by the boost converter and to power the negative pressure source with the stored energy.

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