WO2024208790A1

WO2024208790A1 - Printed circuit board configurations for negative pressure wound therapy devices

Info

Publication number: WO2024208790A1
Application number: PCT/EP2024/058855
Authority: WO
Inventors: Steven Gordon BENNETT; Adam John FISHER; Benjamin James GARDNER; Allan Kenneth Frazer Grugeon HUNT; Kieran MCBETH; Christopher James MILNER; Jamie OWST; Felix Clarence Quintanar; Neil Andrew RAMSBOTTOM; Daniel Lee STEWARD; Liam Bradley James THOMSON; Rhianna WARD
Original assignee: Smith and Nephew PLC; TJ Smith and Nephew Ltd
Current assignee: Smith and Nephew PLC; TJ Smith and Nephew Ltd
Priority date: 2023-04-03
Filing date: 2024-04-02
Publication date: 2024-10-10
Anticipated expiration: 2025-10-03
Also published as: CN120957767A; GB202304922D0; EP4688030A1

Abstract

A negative pressure wound therapy system may include a negative pressure source configured to provide via a fluid flow path negative pressure to a wound covered by a wound dressing and to aspirate fluid from the wound. The wound therapy system can include a multi- layer printed circuit board (PCB) supporting a plurality of electronic components including the negative pressure source, the plurality of electronic components including control circuitry configured to control operation of the negative pressure source, and the multi-layer PCB supporting a plurality of traces electrically connecting at least some of the plurality of electronic components. The multi-layer PCB can include a first layer joined with a second layer to reduce gas leaks in the fluid flow path.

Description

PRINTED CIRCUIT BOARD CONFIGURATIONS FOR NEGATIVE PRESSURE WOUND THERAPY DEVICES

Technical Field

Embodiments described herein relate to apparatuses, systems, and methods the treatment of wounds, for example using dressings in combination with negative pressure wound therapy.

Description of the Related Art

The treatment of open or chronic wounds that are too large to spontaneously close or otherwise fail to heal by means of applying negative pressure to the site of the wound is well known in the art. Negative pressure wound therapy (“NPWT”) systems currently known in the art commonly involve placing a cover that is impermeable or semi-permeable to fluids over the wound, using various means to seal the cover to the tissue of the patient surrounding the wound, and connecting a source of negative pressure (such as a vacuum pump) to the cover in a manner so that negative pressure is created and maintained under the cover. It is believed that such negative pressures promote wound healing by facilitating the formation of granulation tissue at the wound site and assisting the body’s normal inflammatory process while simultaneously removing excess fluid, which may contain adverse cytokines and/or bacteria. However, further improvements in NPWT are needed to fully realize the benefits of treatment.

SUMMARY

A negative pressure wound therapy system can include a negative pressure source configured to provide, via a fluid flow path, negative pressure to a wound and to aspirate fluid from the wound. The system can include an electronic control circuitry configured to control operation of the negative pressure source. The system can include a multi-layer printed circuit board (PCB) with at least a first layer joined with a second layer to reduce gas leaks in the fluid flow path. At least one of the first or second layers can support a plurality of electronic components including the negative pressure source and the electronic control circuitry and a plurality of traces electrically connecting at least some of the plurality of electronic components. The multi-layer PCB can include at least one electric connection between the first and second layers.

The negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. The system can include a gasket positioned between the negative pressure source and the multi-layer PCB and configured to provide a seal to prevent or reduce one or more leaks in the fluid flow path. A portion of the multi-layer PCB facing the gasket may not include any traces. The portion of the multi-layer PCB facing the gasket may not include any holes other than one or more holes configured to exhaust gas aspirated by the negative pressure source.

The negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. The multi-layer PCB can be a flexible printed circuit board. The first layer and the second layer can be at least partially adhered to one another with an adhesive. At least some regions of the first and second layers may not adhered with the adhesive.

The negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. At least one of the first layer or the second layer can include a portion that is transparent. The multi-layer PCB can support a light source positioned adjacent to the portion. The portion may not include adhesive to facilitate transmission of a light emitted by the light source through the multi-layer PCB. The portion can be configured as an optical filter for the light emitted by the light source. The portion can include a mask configured to filter the light emitted by the light source. The light source can include a light emitting diode mounted to the first layer of the multi-layer PCB.

The negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. The first layer can include one or more discontinuities. Conductive material of at least one of the first or second layers can be removed in one or more discontinuities. The second layer can be adhered to the first layer complementary to the one or more discontinuities of the first layer. The one or more discontinuities of the first layer can include a discontinuity that physically and electrically isolates an isolated portion of the first layer from adjacent portions of the first layer. The isolated portion of the first layer can support one or more traces of the plurality of traces. The isolated portion of the first layer can be configured to be folded away from the second layer to connect the one or more traces to one or more of the plurality of electronic components. The isolated portion of the first layer can be configured to connect the one or more traces to the negative pressure source. The isolated portion can include a flexible connector. One or more traces of the plurality of traces can be physically isolated from a discontinuity in the multi-layer PCB to prevent fluid from entering between the first layer and the second layer.

The negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. The system can include a wound dressing configured to be positioned over the wound. The wound dressing can support the negative pressure source and the multi-layer PCB.

Disclosed herein are methods of operating a negative pressure wound therapy system of any of the preceding paragraphs and/or any of the systems, devices, or apparatuses disclosed herein.

A medical treatment or monitoring system can include a treatment or monitoring device. The system can include an electronic control circuitry configured to control operation of the treatment or monitoring device. The system can include and a multi-layer printed circuit board (PCB) with at least a first layer joined with a second layer. At least one of the first or second layers can support a plurality of electronic components including the treatment or monitoring device and a plurality of traces electrically connecting at least some of the plurality of electronic components. The multi-layer PCB can include at least one electric connection between the first and second layers.

The medical treatment or monitoring system of any of the preceding paragraphs and/or any of the systems, apparatuses, or devices disclosed herein can include one or more of the following features. The multi-layer PCB can include one or more discontinuities in which conductive material of at least one of the first or second layers has been removed. The one or more discontinuities can facilitate flexibility of the multi-layer PCB. A region of the multilayer PCB supporting the treatment or monitoring device may not include any traces. The multi-layer PCB can support a light source positioned adjacent to a portion of the multi-layer PCB that is transparent. The portion that is transparent may not include adhesive to facilitate transmission of a light emitted by the light source through the multi-layer PCB. The portion that is transparent can include a mask configured to filter the light emitted by the light source.

Disclosed herein are methods of operating a medical treatment or monitoring system of any of the preceding paragraphs and/or any of the systems, devices, or apparatuses disclosed herein.

Any of the features, components, or details of any of the arrangements or embodiments disclosed in this application, including without limitation any of the apparatus embodiments and any of the negative pressure wound therapy embodiments disclosed herein, are interchangeably combinable with any 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

Figures 1A-1C illustrate a wound dressing incorporating a source of negative pressure and/or other electronic components within the wound dressing;

Figures 2A-2B illustrate an electronics unit that may be incorporated into a wound dressing;

Figure 3 is an exploded perspective view of an electronics assembly enclosing an electronics unit within a housing;

Figure 4A illustrates a bottom perspective view of the electronics assembly of Figure 3;

Figure 4B illustrates a top perspective view of the electronics assembly of Figure 3;

Figure 5 A is an exploded view of a wound dressing incorporating an electronics assembly within the wound dressing layers;

Figure 5B illustrates a cross sectional layout of the material layers of a wound dressing incorporating an electronics assembly within the dressing;

Figure 6 illustrates a multi-layer printed circuit board of the electronics unit;

Figure 7 illustrates the multi-layer printed circuit board of Figure 6 populated with electronic components;

Figures 8A-8D illustrate assembly of an electronics unit

Figure 9 illustrates an assembled electronics unit; and Figure 10 illustrates a folded printed circuit board.

DETAILED DESCRIPTION

Overview

Embodiments disclosed herein relate to apparatuses and methods of treating a wound with reduced pressure, including a source of negative pressure and wound dressing components and apparatuses. These apparatuses and components, including but not limited to wound overlays, backing layers, cover layers, drapes, sealing layers, spacer layers, absorbent layers, transmission layers, wound contact layers, packing materials, fillers and/or fluidic connectors are sometimes collectively referred to herein as dressings.

It will be appreciated that throughout this specification reference is made to a wound. It is to be understood that the term wound is to be broadly construed and encompasses open and closed wounds in which skin may be torn, cut or punctured or where trauma causes a contusion, or any other superficial or other conditions or imperfections on the skin of a patient or otherwise that benefit from reduced pressure treatment. A wound is thus broadly defined as any damaged region of tissue where fluid may or may not be produced. Examples of such wounds include, but are not limited to, abdominal wounds or other large or incisional wounds, either as a result of surgery, trauma, sterniotomies, fasciotomies, or other conditions, dehisced wounds, acute wounds, chronic wounds, subacute and dehisced wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers or the like.

It will be understood that embodiments of the present disclosure are generally applicable to use in NPWT or topical negative pressure ("TNP") therapy systems. Briefly, negative pressure wound therapy assists in the closure and healing of many forms of "hard to heal" wounds by reducing tissue oedema; encouraging blood flow and granular tissue formation; removing excess exudate and may reduce bacterial load (and thus infection risk). In addition, the therapy allows for less disturbance of a wound leading to more rapid healing. TNP therapy systems may also assist on the healing of surgically closed wounds by removing fluid and by helping to stabilize the tissue in the apposed position of closure. A further beneficial use of TNP therapy can be found in grafts and flaps where removal of excess fluid is important and close proximity of the graft to tissue is required in order to ensure tissue viability.

As is used herein, reduced or negative pressure levels, such as -X mmHg, represent pressure levels relative to normal ambient atmospheric pressure, which can correspond to 760 mmHg (or 1 atm, 29.93 inHg, 101.325 kPa, 14.696 psi, 1013.25 mbar, etc.). Accordingly, a negative pressure value of -X mmHg reflects absolute pressure that is X mmHg below 760 mmHg or, in other words, an absolute pressure of (760-X) mmHg. In addition, negative pressure that is "less" or "smaller" than X mmHg corresponds to pressure that is closer to atmospheric pressure (such as, -40 mmHg is less than -60 mmHg). Negative pressure that is "more" or "greater" than -X mmHg corresponds to pressure that is further from atmospheric pressure (such as, -80 mmHg is more than -60 mmHg). In some cases, local ambient atmospheric pressure is used as a reference point, and such local atmospheric pressure may not necessarily be, for example, 760 mmHg.

The negative pressure range can be approximately -80 mmHg, or between about -20 mmHg and -200 mmHg. Note that these pressures are relative to normal ambient atmospheric pressure, which can be 760 mmHg. Thus, -200 mmHg would be about 560 mmHg in practical terms. In some cases, the pressure range can be between about -40 mmHg and -150 mmHg. Alternatively, a pressure range of up to -75 mmHg, up to -80 mmHg or over -80 mmHg can be used. Also in some cases a pressure range of below -75 mmHg can be used. Alternatively, a pressure range of over approximately -100 mmHg, or even -150 mmHg, can be supplied by the negative pressure apparatus.

The systems and methods disclosed herein relate to the use of a wound dressing. The wound dressing may include one or more electrical components in order to provide a therapy function to a wound. In order to provide the therapy function, the wound dressing may be connected to control circuitry that causes the wound dressing to perform wound therapy (e.g., TNP therapy, ultrasound therapy, compression therapy, light therapy, etc.). The control circuitry can drive the wound dressing by providing a drive signal to the wound dressing that causes the wound dressing to perform wound therapy. Wound Dressing

A source of negative pressure (such as a pump) and some or all other components of the TNP system, such as power source(s), sensor(s), connector(s), user interface component(s) (such as button(s), switch(es), speaker(s), screen(s), etc.) and the like, can be integral with the wound dressing. The material layers can include a wound contact layer, one or more absorbent layers, one or more transmission or spacer layers, and a backing layer or cover layer covering the one or more absorbent and transmission or spacer layers. The wound dressing can be placed over a wound and sealed to the wound with the pump and/or other electronic components contained under the cover layer within the wound dressing. The dressing can be provided as a single article with all wound dressing elements (including the pump) pre-attached and integrated into a single unit. A periphery of the wound contact layer can be attached to the periphery of the cover layer enclosing all wound dressing elements as illustrated in Figure 1A-1C.

The pump and/or other electronic components can be configured to be positioned adjacent to or next to the absorbent and/or transmission layers so that the pump and/or other electronic components are still part of a single article to be applied to a patient. The pump and/or other electronics can be positioned away from the wound site. Although certain features disclosed herein may be described as relating to systems and method for controlling operation of a negative pressure wound therapy system in which the pump and/or other electronic components are positioned in or on the wound dressing, the systems and methods disclosed herein are applicable to any negative pressure wound therapy system or any medical device. Figures 1A-1C illustrate a wound dressing incorporating the source of negative pressure and/or other electronic components within the wound dressing. Figures 1A-1C illustrate a wound dressing 100 with the pump and/or other electronics positioned away from the wound site. The wound dressing can include an electronics area 161 and an absorbent area 160. The dressing can comprise a wound contact layer 110 (not shown in Figures 1A-1B) and a moisture vapor permeable film, cover layer or backing layer 113 positioned above the contact layer and other layers of the dressing. The wound dressing layers and components of the electronics area as well as the absorbent area can be covered by one continuous cover layer 113 as shown in Figures 1A-1C. A layer 111 of porous material can be located above the wound contact layer 110. As used herein, the terms porous material, spacer, and/or transmission layer can be used interchangeably to refer to the layer of material in the dressing configured to distribute negative pressure throughout the wound area. This porous layer, or transmission layer, 111 allows transmission of fluid including liquid and gas away from a wound site into upper layers of the wound dressing. In particular, the transmission layer 111 preferably ensures that an open air channel can be maintained to communicate negative pressure over the wound area even when the absorbent layer has absorbed substantial amounts of exudates. The layer 111 should preferably remain open under the typical pressures that will be applied during negative pressure wound therapy as described above, so that the whole wound site sees an equalized negative pressure. The layer 111 may be formed of a material having a three dimensional structure. For example, a knitted or woven spacer fabric (for example Baltex 7970 weft knitted polyester) or a non-woven fabric could be used.

Further, one or more absorbent layers (such as layers 122, 151) for absorbing and retaining exudate aspirated from the wound can be utilized. A superabsorbent material can be used in the absorbent layers 122, 151. The one or more layers 122, 151 of absorbent material may be provided above the transmission layer 111. Since in use each of the absorbent layers experiences negative pressures, the material of the absorbent layer can be chosen to absorb liquid under such circumstances. The absorbent layers 122. 151 may comprise a composite comprising superabsorbent powder, fibrous material such as cellulose, and bonding fibers. The composite can be an airlaid, thermally-bonded composite.

The electronics area 161 can include a source of negative pressure (such as a pump) and some or all other components of the TNP system, such as power source(s), sensor(s), connector(s), user interface component(s) (such as button(s), switch(es), speaker(s), screen(s), etc.) and the like, that can be integral with the wound dressing. For example, the electronics area 161 can include a button or switch (shown in Figures 1 A- IB as being covered by a pull tab). The button or switch can be used for operating the pump (such as, turning the pump on/off).

The electronics area 161 of the dressing can comprise one or more layers of transmission or spacer material and/or absorbent material and electronic components can be embedded within the one or more layers of transmission or spacer material and/or absorbent material. The layers of transmission or absorbent material can have recesses or cut outs to embed the electronic components within whilst providing structure to prevent collapse. As shown in Figure 1C, recesses 128 and 129 can be provided in absorbent layers 151 and 122, respectively.

As used herein the upper layer, top layer, or layer above refers to a layer furthest from the surface of the skin or wound while the dressing is in use and positioned over the wound. Accordingly, the lower surface, lower layer, bottom layer, or layer below refers to the layer that is closest to the surface of the skin or wound while the dressing is in use and positioned over the wound. Additionally, the layers can have a proximal wound-facing face referring to a side or face of the layer closest to the skin or wound and a distal face referring to a side or face of the layer furthest from the skin or wound.

The cover layer may include a cutout 172 positioned over at least a portion of the aperture 128 in the absorbent layer 122 to allow access and fluid communication to at least a portion of the absorbent layers 122 and 151, transmission layer 111, and would contact layer 110 positioned below. An electronics assembly such as described below can be positioned in the apertures 128, 129, and 172 of the first and second absorbent material 151 and 122 and the cover layer 113. The electronics assembly can include a pump, power source, and a printed circuit board as described with reference to Figures 3 and 6-7.

Before use, the dressing can include one or more delivery layers 146 adhered to the bottom surface of the wound contact layer. The delivery layer 146 can cover adhesive or apertures on the bottom surface of the wound contact layer 110. The delivery layer 146 can provided support for the dressing and can assist in sterile and appropriate placement of the dressing over the wound and skin of the patient. The delivery layer 146 can include handles that can be used by the user to separate the delivery layer 146 from the wound contact layer 110 before applying the dressing to a wound and skin of a patient.

Electronics Assembly Incorporated Within the Wound Dressing

Figures 2A-2B illustrate an electronics unit 267 that can be incorporated into a wound dressing. Figure 2A illustrates the top view of the electronics unit. Figure 2B illustrates a bottom or wound facing surface of the electronics unit. The electronics unit 267 can include a pump 272 and one or more power sources 268, such as batteries. The electronics unit 267 can include a circuit board 276 configured to be in electrical communication with the pump 272 and/or power source 268. The circuit board 276 can be flexible or substantially flexible.

As illustrated in Figure 2 A, the electronics unit 267 can include single button or switch 265 on the upper surface of the unit. The single button or switch 265 can be used as an on/off button or switch to stop and start operation of the pump and/or electronic components. The electronics unit 267 can also include one or more vents or exhaust apertures 264 on the circuit board 276 for expelling the air exhausted from the pump. As shown in Figure 2B, a pump outlet exhaust mechanism 274 (sometimes referred to as pump exhaust mechanism or pump outlet mechanism) can be attached to the outlet of the pump 272.

The electronics unit 267 can include a pump inlet protection mechanism 280 as shown in Figure 2B positioned on the portion of the electronics unit closest to the absorbent area and aligned with the inlet of the pump 272. The pump inlet protection mechanism 280 is positioned between the pump inlet and the absorbent area or absorbent layer of the dressing. The pump inlet protection mechanism 280 can include hydrophobic material to prevent fluid from entering the pump 272. The pump inlet protection mechanism 280 (or any of the inlet protection mechanisms disclosed herein) can include a filter.

The upper surface of the electronics unit 267 can include one or more indicators 266 for indicating a condition of the pump and/or level of pressure within the dressing. The indicators can be small LED lights or other light sources that are visible through the dressing components. As will be discussed herein, the dressing components can be at least partially transparent or semi-transparent such that the indicator(s) are visible without any holes in the dressing components. The indicators can be green, yellow, red, orange, or any other color. For example, there can be two lights, one green light and one orange light. The green light can indicate the device is working properly and the orange light can indicate that there is some issue with the pump (such as, leak, saturation level of the dressing, blockage downstream of the pump, exhaust blockage, low battery, or the like). In certain implementations, the indicators can be of a single color (such as, white LEDs), with each indicator being visible through a tinted mask acting as an optical filter to produce variously colored light emissions.

The power source 268 can be in electrical communication with the circuit board 276. One or more power source connections are connected to a surface of the circuit board 276. The circuit board 276 can have other electronics incorporated within. For example, the circuit board 276 may support various sensors including, but not limited to, one or more pressure sensors, temperature sensors, optic sensors and/or cameras, and/or saturation indicators.

Figure 3 illustrates an electronics assembly 300 enclosing an electronics unit within a housing. As illustrated in Figure 3, the housing of the electronics assembly 300 can include a plate 301 and flexible film 302 enclosing the electronics unit 303 within. The electronics unit 303 can include a pump 305, inlet protection mechanism 310, pump exhaust mechanism 306, power source 307, and circuit board 309. The circuit board 309 can be flexible or substantially flexible.

As is illustrated, the pump exhaust mechanism 306 can be an enclosure, such as a chamber. The electronics unit 303 and pump 305 can be used without the inlet protection mechanism 310. However, the pump exhaust mechanism 306 and the pump 305 can sit within an extended casing 316.

The flexible film 302 can be attached to the plate 301 to form a fluid tight seal and enclosure around the electronic components. The flexible film 302 can be attached to the plate at a perimeter of the plate by heat welding, adhesive bonding, ultrasonic welding, RF welding, or any other attachment or bonding technique.

The flexible film 302 can include an aperture 311. The aperture 311 can allow the inlet protection mechanism 310 to be in fluid communication with the absorbent and/or transmission layers of the wound dressing. The perimeter of the aperture 311 of the flexible film 302 can be sealed or attached to the inlet protection mechanism 310 to form a fluid tight seal and enclosure around the inlet protection mechanism 310 allowing the electronic components 303 to remain protected from fluid within the dressing. The flexible film 302 can be attached to the inlet protection mechanism 310 at a perimeter of the inlet protection mechanism 310 by heat welding, adhesive bonding, ultrasonic welding, RF welding, or any other attachment or bonding technique. The inlet protection mechanism 310 can prevent wound exudate or liquids from the wound and collected in the absorbent area 160 of the wound dressing from entering the pump and/or electronic components of the electronics assembly 300.

The electronics assembly 300 illustrated in Figure 3 can be incorporated within the wound dressing such that, once the dressing is applied to the body of the patient, air from within the dressing can pass through the inlet protection mechanism 310 to be pumped out toward the pump exhaust mechanism 306 in communication with an aperture in the casing 316 and the circuit board 309 as described herein.

Figures 4A-B illustrate an electronics assembly 400 including a pump inlet protection mechanism 410 sealed to the exterior of the flexible film 402, similar to the description with reference to Figure 3. Also shown is an exhaust mechanism 406, which can be similar to the exhaust mechanism 306.

Figure 4A illustrates lower, wound facing surface of the electronics assembly 400. Figure 4B shows an upper surface of the plate 401 (which can face the patient or user) of the electronics assembly 400. The upper surface of the plate 401 can include an on/off switch or button cover 443 (illustrated as a pull tab), indicators 444, and/or one or more vent holes 442. Removal of the pull tab 443 can cause activation of the electronics assembly 400, such as provision of power from the power source to the electronics assembly. Further details of operation of the pull tab 443 are described in PCT International Application No. PCT/EP2018/079745, filed October 30, 2018, titled “SAFE OPERATION OF INTEGRATED NEGATIVE PRESSURE WOUND TREATMENT APPARATUSES,” which is incorporated by reference in its entirety herein.

The electronics assembly 400 with the pump inlet protection mechanism 410 extending from and sealed to the film 402 can be positioned within the aperture 172 in the cover layer 113 and absorbent layer(s) (122, 151) as shown in Figure 1C. The perimeter of the electronics assembly 400 can be sealed to a top surface of the outer perimeter of the aperture 172 in the cover layer 113 as shown in Figures 1C and described in more detail with reference to Figure 5A-5B herein. The electronics assembly 400 can be sealed to the cover layer 113 with a sealant gasket, adhesive, heat welding, adhesive bonding, ultrasonic welding, RF welding, or any other attachment or bonding technique. The electronics assembly 400 can be permanently sealed to the cover layer 113 and could not be removed from the cover layer without destroying the dressing.

The electronics assembly 400 can be utilized in a single dressing and disposed of with the dressing. In some cases, the electronics assembly 400 can be utilized in a series of dressings.

Figure 5 A illustrates a wound dressing, such as the one in Figure 1C, incorporating an electronics assembly 500 within the wound dressing layers 590. Figure 5B illustrates a cross- sectional view of the wound dressing incorporating the electronics assembly of Figure 5A. The electronics assembly 500 can be provided within the aperture 172 in the cover layer and apertures 129 and 128 in the first and second absorbent layers 122, 151. The electronics assembly 500 can seal to the outer perimeter of the aperture 172 of the cover layer. The dressing can comprise a wound contact layer 110 and a moisture vapor permeable film, cover layer or backing layer 113 positioned above the contact layer 110 and other layers of the dressing. A layer 111 of porous material can be located above the wound contact layer 110. As used herein, the terms porous material, spacer, and/or transmission layer can be used interchangeably to refer to the layer of material in the dressing configured to distribute negative pressure throughout the wound area. This porous layer, or transmission layer, 111 allows transmission of fluid including liquid and gas away from a wound site into upper layers of the wound dressing. Further, one or more absorbent layers (such as layers 122, 151) for absorbing and retaining exudate aspirated from the wound can be utilized. The one or more layers 122, 151 of absorbent material may be provided above the transmission layer 111. There may be a small aperatured absorbent layer 151 and a large aperture absorbent layer 122. The small apertured absorbent layer 151 can be positioned on top of the large apertured absorbent layer 122. In some cases, the small apertured absorbent layer 151 can be positioned below of the large apertured absorbent layer 122. Before use, the dressing can include one or more delivery layers 146 adhered to the bottom surface of the wound contact layer. The delivery layer 146 can cover adhesive or apertures on the bottom surface of the wound contact layer 110.

Multi-layer Printed Circuit Board

Positioning any of the electronics assemblies or units disclosed herein on a wound dressing can be challenging at least due to the potential exposure of one or more electronic components to fluid (such as, wound exudate) aspirated from the wound and absorbed by the wound dressing. As a result, protection of electronic components against liquid ingress is important. Another challenge is eliminating or reducing any leaks in a fluid flow path used for aspirating fluid from the wound, where the fluid flow path includes an electronics assembly. Potential leak paths can be introduced via holes, programming headers, or PCB features such as fold lines or cutouts. Formation of leaks can adversely affect power source capacity and continuous provision of negative pressure wound therapy. Yet another challenge is reducing the size of an electronics assembly so that can fit of the wound dressing. These and other challenges can be addressed by one or more designs disclosed herein.

In some implementations, any of the electronics assemblies or units disclosed herein can include one or more multi-layer printed circuit boards (PCBs) supporting one or more electronic components. Figure 6 illustrates a multi-layer PCB 600 that can be utilized by any of the devices or systems described herein. For instance, the multi-layer PCB 600 can be part of the electronics unit 267. The multi-layer PCB 600 can be a two-layer PCB with an upper (or top) layer 605a and a lower (or bottom) layer (illustrated in Figures 8A-8B). Designation of the layers as upper and lower is relative and, in some cases, the layer 605a can be called the lower layer and the layer 605b can be called the upper layer. The upper and lower layers of the multi-layer PCB 600 can be joined together by an adhesive (such as, glue). In some cases, one or more intermediate PCB layers can be provided between the upper and lower layers 605a and 605b to increase the density of one or more electronic components.

The lower and upper layers 605a and 605b can include conductive material, such as copper. As described herein, the upper layer 605a of the PCB 600 can include one or more discontinuities 608 whereby at least one of the upper layer 605a or the lower layer 605b is removed. For instance, conductive material of at least one of the upper layer 605a or the lower layer 605b can be removed to form one or more discontinuities 608. Such one or more discontinuities 608 can provide flexibility and can protect electronic components positioned on the PCB 600 from shifting, bending, or breaking due to movement of the patient. For instance, the one or more discontinuities 608 can be formed around the pump 272 or the power source 268, as shown in Figure 7. This can facilitate maintaining provision of negative pressure wound therapy and prevent formation of a short circuit. The one or more discontinuities 608 can be covered with tape, such as Kapton tape.

Additional adhesive can be provided between the upper and lower layers 605a and 605b proximal to the one or more discontinuities 608 in the upper layer in order to maintain the airtight seal, as described herein. In some implementations, adhesive is not provided in the regions of the one or more discontinuities since at least one of the upper layer 605a or the lower layer 605b is removed in those regions.

The multi-layer PCB 600 can be flexible in order to promote patient comfort when the wound dressing supporting the multi-layer PCB 600 is applied at a wound site. Each of the layers 605a and 605b can be made from flexible material. The layers of the multi-layer PCB layers can be made of a dielectric polymer, such as polyimide. The multi-layer PCB 600 and individual layers 605a, 605b can be thin to provide a high degree of flexibility of the multilevel PCB.

The multi-layer PCB 600 can support a plurality of electronic components 610, including any of the electronic components discussed herein (such as, with reference to Figures 2A-2B). The electronic components can include one or more of capacitors, resistors, transistors, pressure sensors, temperature sensors, or the like. At least some of the electronic components can be low-profile components and may be secured to the PCB 600 by surface mount technology (SMT). As described with reference to Figure 7, additional hardware devices can be mounted to multi-layer PCB 600 (such as, to the upper PCB layer 605a) to complete the electronics unit 267.

With continuing reference to Figure 6, the multi-layer PCB 600 can include an integrated electrical connector 620 (sometime referred to as connector 620). The integrated electrical connector 620 can be configured to connect the pump 272 to the multi-layer PCB 600. The integrated electrical connector can include a PCB with one or more electronic components configured to provide an interface between the pump 272 and the one or more electronic components of the multi-layer PCB 600. For instance, a flap 625 can be a flexible PCB.

Instead of connecting the pump 272 to other components mounted on the multi-layer PCB 600 using one or more holes (for instance, to connect to one or more traces on the opposite side of the multi-layer PCB 600), which can disadvantageous^ introduce leaks in the fluid flow path that includes the pump 272, the integrated electrical connector 620 can be used. The integrated electrical connector 620 can include the flap 625, which can flexible. As shown, the flap 625 can be substantially rectangular. The flap 625 can be defined by one or more discontinuities in at least one of the upper layer 605a or the lower layer 605b to provide a portion of at least one of the upper layer 605a or the lower layer 605b that is physically and electrically isolated. The integrated electrical connector 620 can be electrically connected to a first trace 630a and a second trace 630b configured to provide electrical connections between the pump 272 and one or more components of the multi-layer PCB 600. As described with reference to Figures 8A-8B, the integrated electrical connector 620 can utilize the flexible nature of the upper PCB layer 605a to form a secure and durable connection to the pump 272. This may be accomplished without creating additional discontinuities in the multi-layer PCB 600. In certain implementations, additional electrical connectors may be similarly provided to connect other hardware devices.

A pair of openings 640a and 640b can be provided in the multi-layer PCB 600 through which fluid (such as, gas) can be vented outside the wound dressing during provision of negative pressure wound therapy. The openings 640a and 640b can be circular. The openings 640a, 640b can be similar to the vent holes 442. In some cases, one or more filters may be provided to cover the openings 640a and 640b to reduce odor, prevent bacterial contamination, or protect the pump 272. The pump exhaust 274 of the pump 272 can be positioned over the openings 640a and 640b, as shown in Figure 7.

In some cases, the openings 640a, 640b can be the only holes in a region 645 of the multi-layer PCB 600 where the pump exhaust 274 (or the pump 272) is mounted. This design can reduce or eliminate unwanted leaks in the fluid flow path. In some implementations, single opening 640a or 640b can be provided.

Similar to the one or more discontinuities 608, the openings 640a, 640b can have conductive material removed from at least one of the upper layer 605a or the lower layer 605b. This can provide flexibility for venting gas through the openings 640a, 640b and lessen the risk of forming a seal with a rigid surface of the PCB 600, which would prevent venting gas through the openings 640a, 640b.

Conductive material can be removed from at least one of the upper layer 605a or the lower layer 605b along the edges of the PCB 600. This can improve flexibility and provide protection against electrostatic discharge (ESD).

A plurality of traces 650 on the upper layer 605a can provide a plurality of electric connections. To avoid introduction of leaks into the fluid flow path, the traces 650 may not be present in the region 645. Traces 650 can have a raised profile with respect to the surface of the multi-layer PCB 600 and positioning any of the traces 650 in the region 645 may undesirably introduce leaks into the fluid flow path (such as, by providing a raised path for gas to travel along). A gasket (illustrated as 825 in Figures 8A-8B) can be positioned under the pump exhaust 274 to improve the seal and reduce or eliminate leaks. Adhesive can be applied between the upper and lower layers 605a, 605b in the region 645 to prevent or reduce formation of leaks due to gas from passing through the multi-layer PCB 600. The region 645 can have a smooth surface to prevent or reduce formation of leaks. In some cases, the gasket can be omitted.

Figure 7 illustrates the printed circuit board 600 populated with electronic components of an electronics unit 700. The electronics unit 700 can be the same or substantially similar to the electronics unit 267. The electronics unit 700 can include the pump 272 connected to the multi-layer PCB with the integrated electrical connector 620. Operation of the pump 272 can be controlled by the electronics unit 700 as described herein, such as with reference to Figure 3. The pump exhaust 274, pump inlet protection mechanism 280, and power source(s) 268 can be mounted to the multi-layer PCB 600 as shown. The pump exhaust 274 can be centrally located above the openings 640a and 640b, and connected to the pump 272, as described herein. One or more power sources 268 (such as a lithium-ion battery or other battery technology) can be provided at a periphery of the PCB 600 adjacent to the pump 272.

The electronics unit 700 can include one or more indicators for visually providing status of negative pressure wound therapy. Similar to the indicators 266, the one or more indicators can include a first indicator 760a and a second indicator 760b. The first and second indicators 760a, 760b can be light emitting diodes (LEDs) or another type of light source. The indicators 760a, 760b can be mounted on the upper layer 605a, and the multi-layer PCB 600 can be reverse mounted such that the upper layer 605a faces toward the wound. To provide visible status, light from the indicators 760a, 760b can shine through the multi-layer PCB 600. For example, the multi-layer PCB 600 (or one or more regions) can be made from transparent or semi-transparent material to allow the indicators 760a, 760b to be viewed when looking at the bottom layer 605b. The indicators 760a, 760b can be mounted in regions 660a, 660b (shown in Figure 6). Adhesive may not be provided in the regions 660a, 660b so as to not adversely affect the color of the light generated by the indicators 760a, 760b. PCB masking layers (or masks) may not be provided in the regions 660a, 660b so as to not adversely affect the color of the light generated by the indicators 760a, 760b. Advantageously, this design can avoid the use of holes for providing visual indication, as such holes can introduce one or more leaks into the fluid flow path.

The indicators 760a, 760b can be green, yellow, red, orange, or any other color. For example, the first indicator 760a can emit green light indicative of normal operation, and the second indicator 760b can emit orange or yellow light to indicate one or more problems. In certain implementations, any of the indicators 760a or 760b can be of a single color (such as, white LEDs). A mask can be provided on the multi-layer PCB 600 in one or more regions 660a or 660b to act as an optical filter for the light generated by any of the indicators 760a or 760b. The mask can act as a filter to change color of the emitted light to desired color, such as, green, yellow, or orange. For instance, green mask can be provided to change white color emitted by a white LED to green color.

Figures 8A-8B illustrate assembly of the electronics unit 700 of Figure 7. Figure 8A is an exploded view of the multi-layer PCB 600 of Figures 6-7, showing the upper PCB layer 605a separated from the lower PCB layer 605b. In assembly step 810, the upper and lower PCB layers 605a and 605b can be joined together, for instance, by adhesive. The adhesive may also applied proximal to any discontinuities to reduce or eliminate any potential leaks. As described herein, the adhesive may not be applied in any of the one or more discontinuities, particularly when conductive material of both the upper PCB layer 605a and the lower PCB layer 605b has been removed in the discontinuity. The adhesive may be applied throughout the PCB 600, such as by applying an adhesive layer over a first side of the upper layer 605a before joining the upper layer 605a to the lower layer 605b. Step 810 can include separating the flap 625 of the integrated electrical connector 620 from the multi-layer PCB 600. Adhesive may not be applied in the area 635 (shown in Figure 6) of the integrated electrical connector 620. Depending on the method of applying adhesive to form the multi-layer PCB 600, the flap 625 can be separated before the upper layer 605a is joined to the lower layer 605b to prevent the integrated electrical connector 620 from becoming adhered to the lower layer 605b.

In step 820, the flap 625 of the integrated electrical connector 620 can be connected to the pump 272. The electrical terminals of the pump 272 can be soldered to the integrated electrical connector 620 (such as by through-hold soldering or surface mount soldering) or otherwise connected to the integrated electrical connector 620. In certain implementations, the pump 272 and integrated electrical connector 620 can each include corresponding halves of a socket interface to allow the pump 272 to be connected to the multi-layer PCB 600 without soldering or use of holes.

Step 820 can further include providing a gasket 825 (such as a rubber gasket or PTFE gasket) on the multi-layer PCB 600 in preparation for mounting the pump 272. The gasket 825 is configured to form a fluid-tight seal between the multi-layer PCB 600 and the pump 272. The gasket 825 can have a footprint of similar size to that of the pump 272, or the gasket can be elongated to provide a mounting surface for one or more additional hardware devices (such as, power source 268, pump exhaust 274, or similar). In some cases, the gasket 825 can first be adhered to an underside of the pump.

In step 830, the pump 272 is affixed to the upper PCB layer 605a. As described herein, in the region 645 underneath the pump 272 may not have electronic components, traces, and/or vias to reduce or eliminate leaks. The pump 272 can be affixed to the multi-layer PCB 600 by an adhesive, which can be the same adhesive used to join the layers 605a and 605b of the multilayer PCB 600. The adhesive can be selected to prevent or reduce formation of fluid leaks and can be hydrophobic. The electronic components 610 can include a moisture sensor configured to facilitate shutting off the pump 272 responsive to the moisture content satisfying a moisture threshold.

In some cases, the adhesive can be applied to an underside of the pump 272 and adhered to the gasket in step 820, which is then joined to the rest of the electronics unit 700 in step 830. In some implementations, the pump 272 can be affixed to the multi-layer PCB 600 before the flap 625 of the integrated electrical connector 620 is connected to the pump 272. In some implementations, steps 810, 820, and 830 can be preformed in different order.

Figure 8B illustrates the assembled electronics unit 700, including power source(s) 268. The layers 605a and 605b can be flexible allowing the electronics unit 700 to be more comfortably worn by the patient. Because the pump 272 and power source(s) 268 may be rigid, a central region 840 of the electronics unit 700 containing the pump 272 may have little or no flexibility compared to peripheral regions 850 of the multi-layer PCB 600. To mitigate this reduced flexibility, one or more elongated flexible regions 860 can be provided in the multilayer PCB 600 where few or no additional components are mounted. For example, the elongated flexible region(s) 860 can be defined by one or more discontinuities 608 (as shown in Figures 6 and 7), leaving a flexible separation between the pump 272 and power source 268. The flexible separation provided by the elongated flexible regions 860 can allow the electronics unit 700 to have a greater degree of flexibility by dividing the multi-layer PCB 600 into two or more segments. As described herein, the layers of the multi-layer PCB 600 can be stacked on top of one another. Connections between components or traces on different layers can be made using one or more conductive vias or by forming pad-to-pad connections. Figure 8C illustrate connection between an electronic component 870 positioned on the upper PCB layer 605a and an electronic component 880 positioned on the lower PCB layer 605b. The electronic component 870 can have a contact pad 872, and the electronic component 880 can have a contact pad 882. In some cases, one or more of the pads 872 or 882 can be a pin, plate, or the like. Connection between the pads 872 and 882 of the electronic components 870 and 880 can be formed using conductive vias 886 in each of the upper and lower PCB layers 605a and 605b. Figure 8D illustrates connection between the electronic components 870 and 880 when the electronic component 880 is positioned on the top side of the lower PCB layer 605b. The connection can be formed between the pads 872 and 882 using the conductive via 886 in the upper PCB layer 605a. In case where the electronic component 870 is positioned on the bottom side of the upper PCB layer 605a and the electronic component 880 is poisoned on the top side of the lower PCB layer 605b, direct connection between the pads 872 and 882 can be formed without the use of any vias.

Figure 9 illustrates the assembled electronics unit 700. Connection between the pump 272 and the integrated electrical connector 620 is shown. For ease of illustration, the power source(s) 268 are not shown in Figure 9. The flap 625 of the integrated electrical connector 620 can be configured to bend up to 180 degrees to fold over backwards against the upper PCB layer 605a when connected to the pump 272. The folded flap 625 of the electrical connector 620 does not necessarily he flat against the upper PCB layer 605a.

In certain cases, the integrated electrical connector 620 can be elongated to allow multiple folds to be created in the flap 625. For example, the flap 625 can be folded over to create a twist that presents an opposite side of the connector 620 to the hardware device(s), or that causes the connector 620 to emerge from the multi-layer PCB 600 at an oblique angle.

In some cases, the multi-layer PCB 600 can be assembled by adhesion, fixation, welding, or joining of one or more layers together. For example, hot-bar soldering, handheld soldering iron, SMT soldering, or reflow can be utilized for assembling the multi-layer PCB 600. As described herein, the one or more layers can be flexible. The multi-layer PCB 600 can include more than two layers. In some implementations, a folded single-layer PCB can be used in place of a multilayer PCB. Such single- lay er PCB can be flexible. Figure 10 illustrates a folded single- lay er PCB 1000 supporting electronic components and connections (or tracks) 1010. The PCB 1000 when folder can effectively form a dual layer PCB. However, connection between the components can cross the fold (or multiple folds) in the PCB 1000, and it may not be necessary to route the connections from one PCB layer to another.

Conclusion

Disclosed approaches can be advantageous when compared to mitigation techniques for reducing leaks, such as the use of secondary adhesive films, tapes, or coatings to “plug” potential leak paths in a multi-layer PCB. As described herein, a multi-layer PCB can be designed to remove holes that pass through the entirety of the PCB while maintaining the function of electronic components, such as LEDs or pumps. In addition, using the approaches described herein, the multi-layer PCB can retain its flexibility after the electronic components have been mounted on the PCB. This can facilitate continuous provision of negative pressure wound therapy, improve patient safety, and improve patient comfort.

Other Variations

While certain embodiments described herein relate to integrated negative pressure wound therapy systems in which the negative pressure source is supported by the dressing, systems and methods described herein are applicable to any negative pressure wound therapy system or medical system, particularly to systems being positioned on (or worn by) the patient. For example, systems and methods for controlling operation described herein can be used in fluid-proof (such as, water-proof) negative pressure wound therapy systems or medical systems. Such systems can be configured with the negative pressure source and/or electronics being external to the wound dressing, such as with the negative pressure source and/or electronics being positioned in a fluid proof enclosure. Additionally, such systems can be configured to be used within ultrasound delivery devices, negative pressure devices powered by an external power supply, negative pressure devices with a separate pump, and medical devices generally. Any of the embodiments disclosed herein can be used with one or more features disclosed in U.S. Patent No. 7,779,625, titled “DEVICE AND METHOD FOR WOUND THERAPY,” issued August 24, 2010; U.S. Patent No. 7,964,766, titled “WOUND CLEANSING APPARATUS IN SITU,” issued on June 21, 2011 ; U.S. Patent No. 8,235,955, titled "WOUND TREATMENT APPARATUS AND METHOD," issued on August 7, 2012; U.S. Patent No. 7,753,894, titled "WOUND CLEANSING APPARATUS WITH STRESS," issued July 13, 2010; U.S. Patent No. 8,764,732, titled “WOUND DRESSING,” issued July 1, 2014; U.S. Patent No. 8,808,274, titled “WOUND DRESSING,” issued August 19, 2014; U.S. Patent No. 9,061,095, titled “WOUND DRESSING AND METHOD OF USE,” issued June 23, 2015; US Patent No. 10,076,449, issued September 18, 2018, titled "WOUND DRESSING AND METHOD OF TREATMENT"; U.S. Patent Application No. 14/418908, filed January 30, 2015, published as U.S. Publication No. 2015/0190286, published July 9, 2015, titled "WOUND DRESSING AND METHOD OF TREATMENT"; U.S. Patent No. 10,231,878, titled “TISSUE HEALING,” issued March 19, 2019; PCT International Application PCT/GB2012/000587, titled "WOUND DRESSING AND METHOD OF TREATMENT" and filed on July 12, 2012; International Application No. PCT/IB2013/001469, filed May 22, 2013, titled "APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY"; PCT International Application No. PCT/IB2013/002102, filed July 31, 2013, titled “WOUND DRESSING AND METHOD OF TREATMENT”; PCT International Application No. PCT/IB2013/002060, filed July 31, 2013, titled “WOUND DRESSING AND METHOD OF TREATMENT”; PCT International Application No. PCT/IB2013/00084, filed March 12, 2013, titled “REDUCED PRESSURE APPARATUS AND METHODS”; International Application No. PCT/EP2016/059329, filed April 26, 2016, titled “REDUCED PRESSURE APPARATUSES”; PCT International Application No. PCT/EP2017/059883, filed April 26, 2017, titled “WOUND DRESSINGS AND METHODS OF USE WITH INTEGRATED NEGATIVE PRESSURE SOURCE HAVING A FLUID INGRESS INHIBITION COMPONENT”; PCT International Application No. PCT/EP2017/055225, filed March 6, 2017, titled “WOUND TREATMENT APPARATUSES AND METHODS WITH NEGATIVE PRESSURE SOURCE INTEGRATED INTO WOUND DRESSING”; PCT International Application No. PCT/EP2018/074694, filed September 13, 2018, titled “NEGATIVE PRESSURE WOUND TREATMENT APPARATUSES AND METHODS WITH INTEGRATED ELECTRONICS”; PCT International Application No. PCT/EP2018/074701, filed September 13, 2018, titled “NEGATIVE PRESSURE WOUND TREATMENT APPARATUSES AND METHODS WITH INTEGRATED ELECTRONICS”; PCT International Application No. PCT/EP2018/079345, filed October 25, 2018, titled “NEGATIVE PRESSURE WOUND TREATMENT APPARATUSES AND METHODS WITH INTEGRATED ELECTRONICS”; PCT International Application No. PCT/EP2018/079745, filed October 30, 2018, titled “SAFE OPERATION OF INTEGRATED NEGATIVE PRESSURE WOUND TREATMENT APPARATUSES”; each of which is incorporated by reference herein in its entirety.

Although certain embodiments described herein relate to wound dressings, systems and methods disclosed herein are not limited to wound dressings or medical applications. Systems and methods disclosed herein are generally applicable to electronic devices in general, such as electronic devices that can be worn by or applied to a user.

Any value of a threshold, limit, duration, etc. provided herein is not intended to be absolute and, thereby, can be approximate. In addition, any threshold, limit, duration, etc. provided herein can be fixed or varied either automatically or by a user. Furthermore, as is used herein relative terminology such as exceeds, greater than, less than, etc. in relation to a reference value is intended to also encompass being equal to the reference value. For example, exceeding a reference value that is positive can encompass being equal to or greater than the reference value. In addition, as is used herein relative terminology such as exceeds, greater than, less than, etc. in relation to a reference value is intended to also encompass an inverse of the disclosed relationship, such as below, less than, greater than, etc. in relations to the reference value. Moreover, although blocks of the various processes may be described in terms of determining whether a value meets or does not meet a particular threshold, the blocks can be similarly understood, for example, in terms of a value (i) being below or above a threshold or (ii) satisfying or not satisfying a threshold.

Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made. Those skilled in the art will appreciate that in some embodiments, the actual steps taken in the processes illustrated or disclosed may differ from those shown in the figures. Depending on the embodiment, certain of the steps described above may be removed, others may be added. For example, the actual steps or order of steps taken in the disclosed processes may differ from those shown in the figure.

The various components illustrated in the figures or described herein may be implemented as software or firmware on a processor, controller, ASIC, FPGA, or dedicated hardware. The software or firmware can include instructions stored in a non-transitory computer-readable memory. The instructions can be executed by a processor, controller, ASIC, FPGA, or dedicated hardware. Hardware components, such as controllers, processors, ASICs, FPGAs, and the like, can include logic circuitry. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure.

Although the present disclosure includes certain 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 which do not provide all of the features and advantages set forth herein. Accordingly, the scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments herein, and may be defined by claims as presented herein or as presented in the future.

Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, or steps. Thus, such conditional language is not generally intended to imply that features, elements, or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, or steps are included or are to be performed in any particular embodiment. The terms “comprising,” “including,” “having,” and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” 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 mean any subset of a set of elements to which the term “each” is applied.

Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.

Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” “generally,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount.

The scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments in this section or elsewhere in this specification, and may be defined by claims as presented in this section or elsewhere in this specification or as presented in the future. The language of the claims is to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.

Claims

WHAT IS CLAIMED IS:

1. A negative pressure wound therapy system comprising: a negative pressure source configured to provide, via a fluid flow path, negative pressure to a wound and to aspirate fluid from the wound; an electronic control circuitry configured to control operation of the negative pressure source; a multi-layer printed circuit board (PCB) comprising at least a first layer joined with a second layer to reduce gas leaks in the fluid flow path, at least one of the first or second layers supporting a plurality of electronic components including the negative pressure source and the electronic control circuitry and a plurality of conductive traces electrically connecting at least some of the plurality of electronic components, and the multi-layer PCB including at least one electric connection between the first and second layers; and a gasket positioned under the negative pressure source on the multi-layer PCB and configured to provide a seal to prevent or reduce one or more leaks in the fluid flow path, wherein a region of the multi-layer PCB supporting the gasket does not include any conductive traces.

2. The system of claim 1, wherein the region of the multi-layer PCB supporting the gasket does not include any holes other than one or more holes configured to exhaust gas aspirated by the negative pressure source.

3. The system of any one of the preceding claims, wherein the multi-layer PCB includes one or more discontinuities in which conductive material of at least one of the first or second layers has been removed.

4. The system of claim 3, wherein the one or more discontinuities include a discontinuity that physically and electrically isolates an isolated portion of the first layer from adjacent portions of the first layer.

5. The system of claim 4, wherein the isolated portion of the first layer supports one or more conductive traces of the plurality of conductive traces.

6. The system of claim 5, wherein the isolated portion of the first layer is configured to be folded away from the second layer to connect the one or more conductive traces to one or more of the plurality of electronic components.

7. The system of claim 6, wherein the isolated portion of the first layer is configured to connect the one or more conductive traces to the negative pressure source.

8. The system of any one of claims 4 to 7, wherein the isolated portion comprises a flexible connector.

9. The system of any one of the preceding claims, further comprising a wound dressing configured to be positioned over the wound, the wound dressing supporting the negative pressure source and the multi-layer PCB.

10. The system of any one of the preceding claims, wherein the multi-layer PCB comprises a flexible printed circuit board.

11. The system of any one of the preceding claims, wherein the first layer and the second layer are at least partially adhered to one another with an adhesive.

12. The system of claim 11, wherein at least some regions of the first and second layers are not adhered with the adhesive.

13. The system of any one of the preceding claims, wherein at least one of the first layer or the second layer includes a portion that is transparent.

14. The system of claim 13, wherein the multi-layer PCB supports a light source positioned adjacent to the portion that is transparent, and wherein the portion that is transparent does not include adhesive to facilitate transmission of a light emitted by the light source through the multi-layer PCB.

15. The system of claim 14, wherein the portion that is transparent is configured as an optical filter for the light emitted by the light source.

16. The system of claim 15, wherein the portion that is transparent comprises a mask configured to filter the light emitted by the light source.

17. The system of any one of claims 14 to 16, wherein the light source comprises a light emitting diode mounted to the first layer of the multi-layer PCB.

18. A medical treatment or monitoring system comprising: a treatment or monitoring device; an electronic control circuitry configured to control operation of the treatment or monitoring device; and a multi-layer printed circuit board (PCB) comprising at least a first layer joined with a second layer, at least one of the first or second layers supporting a plurality of electronic components including the treatment or monitoring device and a plurality of conductive traces electrically connecting at least some of the plurality of electronic components, and the multi-layer PCB including at least one electric connection between the first and second layers, the multi-layer PCB including one or more discontinuities in which conductive material of at least one of the first or second layers has been removed.

19. The system of claim 18, wherein the one or more discontinuities facilitate flexibility of the multi-layer PCB.

20. The system of any one of claims 18 to 19, wherein a region of the multi-layer PCB supporting the treatment or monitoring device does not include any conductive traces.

21. The system of any one of claims 18 to 20, wherein the multi-layer PCB supports a light source positioned adjacent to a portion of the multi-layer PCB that is transparent, and wherein the portion that is transparent does not include adhesive to facilitate transmission of a light emitted by the light source through the multi-layer PCB.

22. The system of claim 21, wherein the portion that is transparent comprises a mask configured to filter the light emitted by the light source.

23. A method of operating the system of any one of the preceding claims.