WO2020011690A1

WO2020011690A1 - Negative pressure wound therapy device with primary and auxiliary systems

Info

Publication number: WO2020011690A1
Application number: PCT/EP2019/068200
Authority: WO
Inventors: Nicola BRANDOLINI; Felix Clarence Quintanar
Original assignee: T.J.Smith And Nephew,Limited
Priority date: 2018-07-13
Filing date: 2019-07-08
Publication date: 2020-01-16
Also published as: GB201811498D0

Abstract

A negative pressure wound therapy apparatus can include a first source of negative pressure and a first power source, the first source of negative pressure configured to supply, via a fluid flow path, negative pressure to a wound covered by a wound dressing, and the first power source configured to provide electrical power to the first source of negative pressure. The negative pressure wound therapy apparatus can further include a second source of negative pressure and a second power source, the second source of negative pressure configured to supply, via the fluid flow path, negative pressure to the wound, when the first source is not supplying negative pressure to the wound, and the second power source configured to provide electrical power to the second source of negative pressure, the second source of negative pressure being different from the first source of negative pressure.

Description

NEGATIVE PRESSURE WOUND THERAPY DEVICE WITH PRIMARY AND

AUXIUIARY SYSTEMS

Field

Embodiments of the present disclosure relate to methods and apparatuses for dressing and treating a wound with reduced pressure therapy or topical negative pressure (TNP) therapy. In particular, but without limitation, embodiments disclosed herein relate to negative pressure therapy devices, methods for controlling the operation of TNP systems, and methods of using TNP systems. In addition, embodiments disclosed herein relate to primary and auxiliary systems for negative pressure therapy devices.

Description of the Related Art

Many different types of wound dressings are known for aiding in the healing process of a human or animal. These different types of wound dressings include many different types of materials and layers, for example, gauze, pads, foam pads or multi-layer wound dressings. Topical negative pressure (TNP) therapy, sometimes referred to as vacuum assisted closure, negative pressure wound therapy, or reduced pressure wound therapy, is widely recognized as a beneficial mechanism for improving the healing rate of a wound. Such therapy is applicable to a broad range of wounds such as incisional wounds, open wounds, and abdominal wounds or the like.

TNP therapy assists in the closure and healing of wounds by reducing tissue edema, encouraging blood flow, stimulating the formation of granulation tissue, removing excess exudates and may reduce bacterial load. Thus, TNP therapy helps with reducing infection to the wound. Furthermore, TNP therapy permits less outside disturbance of the wound and promotes more rapid healing.

For TNP therapy to be effective, it is undesirable to have unscheduled interruptions in the provision of therapy, particularly when such interruptions are prolonged. Interruptions in the delivery of therapy can lead many complications, including pooling of wound exudate, infection, skin maceration, or the like. There exists a need to eliminate or limit unscheduled interruptions in the provision of TNP therapy. SUMMARY

A negative pressure wound therapy apparatus includes a first housing at least partially enclosing a first source of negative pressure and a first power source. The first source of negative pressure can be configured to supply, via a fluid flow path, negative pressure to a wound covered by a wound dressing, and the first power source can be configured to provide electrical power to the first source of negative pressure.

The negative pressure wound therapy apparatus can also include a second source of negative pressure and a second power source. The second source of negative pressure can be configured to supply, via the fluid flow path, negative pressure to the wound, when the first source is not supplying negative pressure to the wound, and the second power source can be configured to provide electrical power to the second source of negative pressure. The second source of negative pressure can be different from the first source of negative pressure, and the second power source can be different from the first power source.

The negative pressure wound therapy apparatus of any of the preceding paragraphs can include one or more of the following features. The negative pressure wound therapy apparatus can further include a sensor configured to determine at least one condition associated with one or more of the first housing, the first source of negative pressure, the first power source, or fluid flow path. The negative pressure wound therapy apparatus can also include a control circuit configured to, based on determining that the at least one condition satisfies a threshold, determine that the first source of negative pressure is unable to supply negative pressure to the wound, and in response to the determination, deactivate the first source of negative pressure and activate the second source of negative pressure to supply negative pressure to the wound.

The negative pressure wound therapy apparatus of any of the preceding paragraphs can include one or more of the following features. The sensor can include a temperature sensor configured to sense temperature of the first power source, and the threshold can correspond to overheating of the first power source. The sensor can also include a pressure sensor configured to sense pressure in the fluid flow path, and the threshold can correspond to overpressure in the fluid flow path. The sensor can include a moisture sensor configured to sense ingress of liquid into an interior of the first housing, and the threshold can correspond to presence of liquid in the interior of the first housing. The control circuit comprises a comparator.

The negative pressure wound therapy apparatus of any of the preceding paragraphs can include one or more of the following features. The negative pressure wound therapy apparatus can further include a second housing at least partially enclosing the second source of negative pressure and the second power source. The first housing can at least partially enclose the second housing. The apparatus can include a valve positioned in the fluid flow path and fluidically connected to the first and second sources of negative pressure, wherein the control circuit can be further configured to operate the valve to switch supply of negative pressure from the first negative pressure source to the second negative pressure source in response to the determination. The second power source can be configured to provide electrical power to the control circuit. The second power source can be configured to provide electrical power to the control circuit in response to malfunction or failure of the first power source. The sensor can include a fuse. The at least one condition can be associated with malfunction or potential malfunction of the first source of negative pressure or the first power source.

A method of operating a negative pressure wound therapy apparatus that includes a first housing can include, via a fluid flow path, providing from a first source of negative pressure enclosed by the first housing negative pressure to a wound covered by a wound dressing, the first source of negative pressure receiving electrical power from a first power source enclosed by the first housing. The method can further include, by a sensor, detecting at least one condition associated with one or more of the first housing, the first source of negative pressure, the first power source, or fluid flow path. The method can further include, by a control circuit, based on determining that the at least one condition detected by the sensor satisfies a threshold, determining that the first source of negative pressure is unable to supply negative pressure to the wound. The method can further include, in response to the determination, deactivating the first source of negative pressure and activating a second source of negative pressure to supply negative pressure to the wound via the fluid flow path, the second source of negative pressure receiving power from a second power source different from the first power source.

The method of any of the preceding paragraphs can include one or more of the following features. The sensor can be configured to sense temperature of the first power source, and the threshold can correspond to overheating of the first power source. The sensor can be configured to sense pressure in the fluid flow path, and the threshold can correspond to overpressure in the fluid flow path.

The method of any of the preceding paragraphs can include one or more of the following features. The sensor can be configured to sense ingress of liquid into an interior of the first housing, and the threshold can correspond to a presence of liquid in the interior of the first housing. The control circuit can comprise a comparator. The apparatus can further include a second housing at least partially enclosing the second source of negative pressure and the second power source. The first housing can at least partially enclose the second housing. Activating the second source of negative pressure includes switching supply of negative pressure from the first negative pressure source to the second negative pressure source. Switching supply of negative pressure can include operating a valve. The control circuit can receive power from the second power source. The control circuit can receive power from the second power source in response to malfunction or failure of the first power source. The sensor can include a fuse. The at least one condition can be associated with malfunction or potential malfunction of the first source of negative pressure or the first power source.

BRIEF DESCRIPTION OF THE DRAWINGS

Disclosed embodiments will now be described hereinafter, by way of example only, with reference to the accompanying drawings in which:

Figure 1 illustrates a reduced pressure wound therapy system.

Figures 2A-2C illustrate a pump assembly and canister.

Figure 3 illustrates a pump assembly including an auxiliary system negative pressure wound therapy.

Figure 4 illustrates an auxiliary negative pressure wound therapy system. Figure 5 illustrates an auxiliary negative pressure wound therapy system.

DETAILED DESCRIPTION

Overview

Embodiments disclosed herein relate to systems and methods of treating a wound with reduced pressure. 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, etc.). Accordingly, a negative pressure value of -X mmHg reflects absolute pressure that is XmmHg 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 (e.g., -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 (e.g., -80 mmHg is more than -60 mmHg). In some embodiments, local ambient atmospheric pressure is used as a reference point, and such local atmospheric pressure may not necessarily be, for example, 760 mmHg.

Embodiments of the present invention are generally applicable to use in topical negative pressure ("TNP") or reduced pressure therapy systems. Briefly, negative pressure wound therapy assists in the closure and healing of many forms of '¾ard to heal" wounds by reducing tissue oedema, encouraging blood flow and granular tissue formation, or removing excess exudate and can 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 can also assist in the healing of surgically closed wounds by removing fluid. In some embodiments, TNP therapy helps 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.

A negative pressure wound therapy apparatus can include a dressing configured to be placed over a wound and a source of negative pressure configured to be in fluid communication with the dressing. The source of negative pressure is configured to provide negative pressure to the wound. The apparatus can also include a canister configured to collect exudate removed from the wound. The canister can be configured to be in fluid communication with the dressing and the negative pressure source. The apparatus can also include a pressure sensor configured to monitor pressure signals generated by the negative pressure source and a controller. The controller can be configured to determine a level of exudate in the canister (or in the dressing) based at least in part on one or more characteristics of the monitored pressure signals. The one or more characteristics of the pressure signals can change as a level of exudate in the canister increases.

A method of operating a negative pressure wound therapy apparatus can include monitoring pressure signals generated by a negative pressure source in fluid communication with a dressing and a canister. The method can also include determining a level of exudate in the canister (or in the dressing) based at least in part on one or more characteristics of the monitored pressure signals. The one or more characteristics of the pressure signals can change as a level of exudate in the canister increases.

Systems and methods for determining an amount of flow restriction or reduced volume in front of a negative pressure can utilize one or more characteristics of monitored pressure signals. For example, the magnitude of the pressure signals can increase as restriction to flow increase, which effectively reduces the volume in front of a negative pressure source. The volume in front of the negative pressure source may decrease due to filling of a canister or dressing with exudate removed from a wound.

Negative Pressure System

Figure 1 illustrates a negative or reduced pressure wound treatment (or TNP) system 100 comprising a wound filler 130 placed inside a wound cavity 110, the wound cavity sealed by a wound cover 120. The wound filler 130 in combination with the wound cover 120 can be referred to as wound dressing. A single or multi lumen tube or conduit 140 is connected the wound cover 120 with a pump assembly 150 configured to supply reduced pressure. The wound cover 120 can be in fluidic communication with the wound cavity 1 10. In any of the system embodiments disclosed herein, as in the embodiment illustrated in Figure 1, the pump assembly can be a canisterless pump assembly (meaning that exudate is collected in the wound dressing is transferred via tube 140 for collection to another location). However, any of the pump assembly embodiments disclosed herein can be configured to include or support a canister. Additionally, in any of the system embodiments disclosed herein, any of the pump assembly embodiments can be mounted to or supported by the dressing, or adjacent to the dressing. The wound filler 130 can be any suitable type, such as hydrophilic or hydrophobic foam, gauze, inflatable bag, and so on. The wound filler 130 can be conformable to the wound cavity 1 10 such that it substantially fills the cavity at atmospheric pressure, and also may have a substantially reduced compressed volume when under negative pressure. The wound cover 120 can provide a substantially fluid impermeable seal over the wound cavity 110. The wound cover 120 can have a top side and a bottom side, and the bottom side adhesively (or in any other suitable manner) seals with wound cavity 1 10. The conduit 140 or any other conduit disclosed herein can be formed from polyurethane, PVC, nylon, polyethylene, silicone, or any other suitable material.

In some cases, the wound cover 120 can have a port (not shown) configured to receive an end of the conduit 140. In some cases, the conduit 140 can otherwise pass through or under the wound cover 120 to supply reduced pressure to the wound cavity 1 10 so as to maintain a desired level of reduced pressure in the wound cavity. The conduit 140 can be any suitable article configured to provide at least a substantially sealed fluid flow pathway between the pump assembly 150 and the wound cover 120, so as to supply the reduced pressure provided by the pump assembly 150 to wound cavity 1 10.

The wound cover 120 and the wound filler 130 can be provided as a single article or an integrated single unit. In some cases, no wound filler is provided and the wound cover by itself may be considered the wound dressing. The wound dressing may then be connected, via the conduit 140, to a source of negative pressure, such as the pump assembly 150. In some cases, though not required, the pump assembly 150 can be miniaturized and portable, although larger conventional pumps such can also be used.

The wound cover 120 can be located over a wound site to be treated. The wound cover 120 can form a substantially sealed cavity or enclosure over the wound site. In some cases, the wound cover 120 can be configured to have a film having a high water vapour permeability to enable the evaporation of surplus fluid, and can have a superabsorbing material contained therein to safely absorb wound exudate. It will be appreciated that throughout this specification reference is made to a wound. In this sense it is to be understood that the term wound is to be broadly construed and encompasses open and closed wounds in which skin is tom, cut or punctured or where trauma causes a contusion, or any other surficial 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, acute wounds, chronic wounds, surgical incisions and other incisions, subacute and dehisced wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, bums, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers or the like. In some cases, the components of the TNP system described herein can be particularly suited for incisional wounds that exude a small amount of wound exudate.

In some cases, the system is designed to operate without the use of an exudate canister. Some embodiments can be configured to support an exudate canister. In some cases, configuring the pump assembly 150 and tubing 140 so that the tubing 140 can be quickly and easily removed from the pump assembly 150 can facilitate or improve the process of dressing or pump changes, if necessary. Any of the pump embodiments disclosed herein can be configured to have any suitable connection between the tubing and the pump.

In some cases, the pump assembly 150 can be configured to deliver negative pressure at a desired negative pressure setpoint, which can be selected or programmed to be approximately -80 mmHg, or between about -20 mmHg and -200 mmHg (e.g., as selected by a user). Note that these pressures are relative to normal ambient atmospheric pressure 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 -7 5 mmHg, up to -80 mmHg or over -80 mmHg can be used. Also in other cases a pressure range of below -7 5 mmHg can be used. Alternatively a pressure range of over approximately -100 mmHg, or even 150 mmHg, can be supplied by the pump assembly 150.

In some cases, the pump assembly 150 is configured to provide continuous or intermittent negative pressure therapy. Continuous therapy can be delivered at above -25 mmHg, -25 mmHg, -40 mmHg, -50 mmHg, -60 mmHg, -70 mmHg, -80 mmHg, - 90 mmHg, -100 mmHg, -120 mmHg, -140 mmHg, -160 mmHg, -180 mmHg, -200 mmHg, or below - 200 mmHg. Intermittent therapy can be delivered between low and high negative pressure set points. Low set point can be set at above 0 mmHg, 0 mmHg, -25 mmHg, -40 mmHg, -50 mmHg, -60 mmHg, -70 mmHg, -80 mmHg, -90 mmHg, -100 mmHg, -120 mmHg, -140 mmHg, -160 mmHg, -180 mmHg, or below -180 mmHg. High set point can be set at above - 25 mmHg, -40 mmHg, -50 mmHg, -60 mmHg, -70 mmHg, -80 mmHg, -90 mmHg, -100 mmHg, -120 mmHg, -140 mmHg, -160 mmHg, -180 mmHg, -200 mmHg, or below -200 mmHg. During intermittent therapy, negative pressure at low set point can be delivered for a first time duration, and upon expiration of the first time duration, negative pressure at high set point can be delivered for a second time duration. Upon expiration of the second time duration, negative pressure at low set point can be delivered. The first and second time durations can be same or different values. The first and second durations can be selected from the following range: less than 2 minutes, 2 minutes, 3 minutes, 4 minutes, 6 minutes, 8 minutes, 10 minutes, or greater than 10 minutes. In some cases, switching between low and high set points and vice versa can be performed according to a step waveform, square waveform, sinusoidal waveform, and the like.

In operation, the wound filler 130 is inserted into the wound cavity 110 and wound cover 120 is placed so as to seal the wound cavity 1 10. The pump assembly 150 provides a source of a negative pressure to the wound cover 120, which is transmitted to the wound cavity 110 via the wound filler 130. Fluid (e.g., wound exudate) is drawn through the conduit 140, and can be stored in a canister. In some cases, fluid is absorbed by the wound filler 130 or one or more absorbent layers (not shown).

Wound dressings that may be utilized with the pump assembly and other embodiments of the present application include Renasys-F, Renasys-G, Renasys AB, and Pico Dressings available from Smith & Nephew. Further description of such wound dressings and other components of a negative pressure wound therapy system that may be used with the pump assembly and other embodiments of the present application are found in U.S. Patent Publication Nos. 2012/01 16334, 201 1/0213287, 201 1/0282309, 2012/0136325,

2013/01 10058, which are incorporated by reference in their entireties. In other embodiments, other suitable wound dressings can be utilized. Pump Assembly and Canister

Figure 2A illustrates a front view 200A of a pump assembly 230 and canister 220. As is illustrated, the pump assembly 230 and the canister 220 are connected, thereby forming a device. The pump assembly 230 comprises one or more indicators, such as visual indicator 202 configured to indicate alarms and visual indicator 204 configured to indicate status of the TNP system. The indicators 202 and 204 can be configured to alert a user to a variety of operating or failure conditions of the system, including alerting the user to normal or proper operating conditions, pump failure, power supplied to the pump or power failure, detection of a leak within the wound cover or flow pathway, suction blockage, or any other similar or suitable conditions or combinations thereof. In some cases, the pump assembly 230 can comprise additional indicators. In some cases, a single indicator is used. In other cases, multiple indicators are used. Any suitable indicator can be used such as visual, audio, tactile indicator, and so on. The indicator 202 can be configured to signal alarm conditions, such as canister full (or dressing full in case of a canisterless system), power low, conduit 140 disconnected, seal broken in the wound seal 120, and so on. The indicator 202 can be configured to display red flashing light to draw user's attention. The indicator 204 can be configured to signal status of the TNP system, such as therapy delivery is ok, leak detected, and so on. The indicator 204 can be configured to display one or more different colors of light, such as green, yellow, etc. For example, green light can be emitted when the TNP system is operating properly and yellow light can be emitted to indicate a warning.

The pump assembly 230 comprises a display or screen 206 mounted in a recess 208 formed in a case of the pump assembly 230. In some cases, the display 206 can be a touch screen display. In some cases, the display 206 can support playback of audiovisual (AV) content, such as instructional videos. As explained below, the display 206 can be configured to render a number of screens or graphical user interfaces (GUis) for configuring, controlling, and monitoring the operation of the TNP system. The pump assembly 230 comprises a gripping portion 210 formed in the case of the pump assembly. The gripping portion 210 can be configured to assist the user to hold the pump assembly 230, such as during removal of the canister 220. In some cases, the canister 220 can be replaced with another canister, such as when the canister 220 has been filled with exudate. The canister 220 can include solidifier material.

The pump assembly 230 comprises one or more keys or buttons 212 configured to allow the user to operate and monitor the operation of the TNP system. As is illustrated, in some cases, there buttons 2l2a, 2l2b, and 2l2c are included. Button 2l2a can be configured as a power button to turn on/off the pump assembly 230. Button 2l2b can be configured as a play/pause button for the delivery of negative pressure therapy. For example, pressing the button 212b can cause therapy to start, and pressing the button 212b afterward can cause therapy to pause or end. Button 212c can be configured to lock the display 206 or the buttons 212. For instance, button 212c can be pressed so that the user does not unintentionally alter the delivery of the therapy. Button 2l2c can be depressed to unlock the controls. In other cases, additional buttons can be used or one or more of the illustrated buttons 212a, 212b, or 2l2c can be omitted. In some cases, multiple key presses or sequences of key presses can be used to operate the pump assembly 230.

The pump assembly 230 includes one or more latch recesses 222 formed in the cover. In the illustrated embodiment, two latch recesses 222 can be formed on the sides of the pump assembly 230. The latch recesses 222 can be configured to allow attachment and detachment of the canister 220 using one or more canister latches 221. The pump assembly 230 comprises an air outlet 224 for allowing air removed from the wound cavity 110 to escape. Air entering the pump assembly can be passed through one or more suitable filters, such as antibacterial filters. This can maintain reusability of the pump assembly. The pump assembly 230 includes one or more strap mounts 226 for connecting a carry strap to the pump assembly 230 or for attaching a cradle. In the illustrated embodiment, two strap mounts 226 can be formed on the sides of the pump assembly 230. In some cases, various of these features are omitted or various additional features are added to the pump assembly 230.

The canister 220 is configured to hold fluid (e.g., exudate) removed from the wound cavity 1 10. The canister 220 includes one or more latches 221 for attaching the canister to the pump assembly 230. In the illustrated embodiment, the canister 220 comprises two latches 221 on the sides of the canister. The exterior of the canister 220 can formed from frosted plastic so that the canister is substantially opaque and the contents of the canister and substantially hidden from plain view. The canister 220 comprises a gripping portion 214 formed in a case of the canister. The gripping portion 214 can be configured to allow the user to hold the pump assembly 220, such as during removal of the canister from the apparatus 230. The canister 220 includes a substantially transparent window 216, which can also include graduations of volume. For example, the illustrated 300 mL canister 220 includes graduations of 50 mL, 100 mL, 150 mL, 200 mL, 250 mL, and 300 mL. Other embodiments of the canister can hold different volume of fluid and can include different graduation scale. The canister 220 comprises a tubing channel 218 for connecting to the conduit 140. In some cases, various of these features, such as the gripping portion 214, are omitted or various additional features are added to the canister 220.

Figure 2B illustrates a rear view 200B of the pump assembly 230 and canister 220. The pump assembly 230 comprises a speaker port 232 for producing or radiating sound. The pump assembly 230 includes a filter access door 234 for accessing and replacing one or more filters, such as odor filter, antibacterial filters, etc. The access door 234 can be used to access a chamber (such as a plenum chamber) in which noise suppressing or sound absorbing material is placed. The chamber and sound absorbing material can be part of a silencing system that is used to suppress or absorb noise generated by the source of negative pressure. Sound absorbing material can serve to break up sound waves as travel (or reverberate) through the chamber. Sound absorbing material can further function as an odor suppressant. For example, sound absorbing material can be impregnated with activated charcoal for odor suppression. The access door 234 can further include a seal (such as a sealing gasket) for tight closure of the chamber. Additional details of the silencing system are described in U.S. Patent Publication No. 2010/0185165, which is incorporated by reference in its entirety.

The pump assembly 230 comprises a gripping portion 236 formed in the case of the pump assembly. As is illustrated, the gripping portion 236 is a recess formed in the outer casing ofthe pump assembly 230. In some cases, the gripping portion 236 may include rubber, silicone, etc. coating. The gripping portion 236 can be configured (e.g., positioned and dimensioned) to allow the user to firmly hold the pump assembly 230, such as during removal of the canister 220. The pump assembly 230 includes one or more covers 238 configured as screw covers or feet or protectors for placing the pump assembly 230 on a surface. The covers 230 can be formed out of rubber, silicone, or any other suitable material. The pump assembly 230 comprises a power jack 239 for charging and recharging an internal power source of the pump assembly. In some cases, the power jack 239 is a direct current (DC) jack. In some cases, the pump assembly can comprise a disposable power source, such as batteries, so that no power jack is needed.

The canister 220 includes one or more feet 244 for placing the canister on a surface. The feet 244 can be formed out of rubber, silicone, or any other suitable material and can be angled at a suitable angle so that the canister 220 remains stable when placed on the surface. The canister 220 comprises a tube mount relief 246 configured to allow one or more tubes to exit to the front of the device. The canister 220 includes a stand or kickstand 248 for supporting the canister when it is placed on a surface. As explained below, the kickstand 248 can pivot between an opened and closed position. In closed position, the kickstand 248 can be latched to the canister 220. In some cases, the kickstand 248 can be made out of opaque material, such as plastic. In other cases, the kickstand 248 can be made out of transparent material. The kickstand 248 includes a gripping portion 242 formed in the kickstand. The gripping portion 242 can be configured to allow the user to place the kickstand 248 in the closed position. The kickstand 248 comprises a hole 249 to allow the user to place the kickstand in the open position. The hole 249 can be sized to allow the user to extend the kickstand using a finger.

Figure 2C illustrates a view 200C of the pump assembly 230 separated from the canister 220. The pump assembly 230 includes a vacuum attachment or connector 252 through which a vacuum pump communicates negative pressure to the canister 220. The connector 252 can correspond to the inlet of the pump assembly. The pump assembly 230 comprises a USB access door 256 configured to allow access to one or more USB ports. In some cases, the USB access door is omitted and USB ports are accessed through the door 234. The pump assembly 230 can include additional access doors configured to allow access to additional serial, parallel, or hybrid data transfer interfaces, such as SD, Compact Disc (CD), DVD, FireWire, Thunderbolt, PCI Express, and the like. In other cases, one or more of these additional ports are accessed through the door 234. Figure 3 illustrates a view 300 of the interior components of the pump assembly 230. The pump assembly 230 can include various components, such as a canister connector 252 which includes a sealing ring 253, control printed circuit board (PCB) 260, peripherals PCB 262 (e.g., for USB connectivity), power supply PCB 264, primary vacuum pump 266, power source (e.g., rechargeable battery), auxiliary device 268 (e.g., one or more of an auxiliary pump and auxiliary power supply), speaker 270, and light guide or pipe 272 (e.g., for status indication using guided light emitted by one or more LEDs). In some cases, auxiliary device can be positioned on or supported by the exterior of the pump assembly housing or be separate from the pump assembly housing. Further details of status indication are provided in U.S. Patent No. 8,294,586, which is incorporated by reference in its entirety. Other components can be included, such as electrical cables, connectors, tubing, valves, filters, fasteners, screws, holders, and so on. In some cases, the pump assembly 230 can comprise alternative or additional components.

Auxiliary Therapy

Figure 4 schematically illustrates an auxiliary negative pressure wound therapy system.

Auxiliary system, such as the device 268, can include a primary negative pressure source or pump 330 (sometimes referred to as the primary pump or main pump) powered by a primary power source 310 and an auxiliary negative pressure source or pump 410 (sometimes referred to as the auxiliary pump) powered by an auxiliary power source 420, such as one or more batteries. Auxiliary power source 420 can be rechargeable. In some cases, the auxiliary pump 410 and the auxiliary power source 420 are housed within a common housing, which can be the same housing as that of the primary pump. Alternatively, the auxiliary pump 410 and auxiliary power source 420 can be disposed within their individual housing(s), which can be separate from that of the primary negative pressure pump. Primary pump 330 can be same as or similar to the pump 266.

The auxiliary pump 410 can operate in a substantially similar fashion to the primary pump 330, such as the pump 266 of the assembly 150 as described above. The auxiliary pump 410 can supply, via a fluid flow path, negative pressure to the wound when the primary pump 330 is not supplying negative pressure to the wound. The auxiliary power source 420 can provide electrical power to the auxiliary pump 410. The auxiliary device 268 can be configured to operate independently from the main pump 330 to provide negative pressure wound therapy to the wound in case of failure of one or more of the primary pump 330 or primary power source 310. For example, the failure can include one or more of primary pump malfunction (such as, excessive pressure at the wound), overheating of the primary power source or pump (which can lead to fire), fluid ingress into housing enclosing the primary pump and primary power source, cracking of the housing, contamination of the components, or the like.

Auxiliary device 268 can operate with a full or reduced set of features to continue providing negative pressure wound therapy to the wound thereby reducing or eliminating therapy interruptions due to malfunction of the primary pump or power source. For example, auxiliary device 268 may provide therapy at a particular negative pressure, such as -80 mmHg, that cannot be varied. Continuous or substantially continuous provision of negative pressure wound therapy following malfunction of the primary pump or power source can reduce or eliminate skin maceration, bacterial infection, exudate pooling, or the like, which can be essential for patient safety. Provision of therapy from the auxiliary device can provide time for repairing the primary pump or power source.

The system can include one or more sensors 430 that can determine at least one condition associated with malfunction or potential malfunction of the primary pump or power source. As described herein, such condition can include status of the housing, the source of negative pressure, the power source, or the fluid flow path. A control circuit 440 (for example, a comparator, a processor, or the like) can process the one or more signals from the one or more sensors 430 to determine that the primary pump 330 is unable to supply negative pressure wound therapy to the wound. Such a determination can be made based on determining that at least one condition, measured for instance by a sensor 430, satisfies a threshold. For example, the at least one sensor 430 can include one or more of a temperature sensor, a pressure sensor, and a moisture sensor, respectively capable of sensing the temperature, pressure, impact, or moisture of the primary pump 330 or power source 310. The at least one sensor can be a fuse, such as a fuse configured to detect or indicate fluid ingress, cracking of the housing, contamination, or the like. The control circuit 440 can compare the data recorded by the at least one sensor 430 against at least one threshold in order to determine if provision of negative pressure wound therapy should be switched to the auxiliary device 268. If the control circuit 440 determines that the primary pump 330 cannot provide therapy, the control circuit 440 can deactivate or disable the primary pump 330 device and activate or enable the auxiliary device 268 to provide negative pressure wound therapy to the wound. Disabling of the primary pump 330 can include disconnecting load, including the primary pump 330, from the primary battery. Enabling the auxiliary device 268 can include activating one or more of the auxiliary power source 420 or auxiliary pump 410. Switching provision of negative pressure wound therapy to the auxiliary device 268 can be performed using one or more valves, such as solenoid valves, to switch fluid flow to the auxiliary pump 410. In some cases, the control circuit 440 can (based on sensor input) determine that the primary pump 330 is able to provide therapy and in response switch provision of therapy from the auxiliary pump to the primary pump.

For example, the sensor 430 can be an electronic pressure sensor, which can be mounted on the control PCB 260. The sensor 430 can monitor the pressure being provided by the primary pump 330. The pressure measurement by the sensor 430 can then be compared against threshold pressure levels by the control circuit 440. In response to the pressure levels being below or above thresholds, the control circuit 440 can determine that the pressure being provided by the pump assembly 330 is insufficient (or is too high) and switch provision of therapy to the auxiliary device 268. As another example, the sensor 430 can be a temperature sensor that can cause the control circuit 440 to switch provision of therapy to the auxiliary device 268 when it is determined, for instance, that the primary power source is overheating. In some cases, the sensor 430 can monitor the primary power source and be able to detect if it is losing power.

The at least one sensor 430 or the control circuit 440 can receive power from the auxiliary power source 420. Thus, operation of the at least one sensor 430 and the control circuit 440 can continue even when the primary power source has malfunctioned or failed. As described herein in connection with the indicators 202 and 204, the auxiliary device 268 can include one or more auxiliary indicators configured to provide alarms or indicate a status of the TNP system. These auxiliary indicators can be powered by the auxiliary power source 420. Thus, in the event that a failure of the primary device impacts the indicators 202 or 204 or other components of the primary system that provide user indications, the user will still be notified of the status of the TNP system using the auxiliary indicators. Alarms or status indications can include providing indication(s) that negative pressure wound therapy is being delivered by the auxiliary device. Such indication can signal the need to address the failure of the primary device, such as repair or replace the primary device, particularly when the auxiliary device is configured to provide negative pressure wound therapy with reduced set of features as described herein.

The auxiliary device 268 can be designed to withstand more extreme conditions than the primary pump 330 or power source 300. For instance, the auxiliary device can be designed to operate for shorter periods in extreme temperatures. The ephemeral nature of the auxiliary device 268 may allow for operating conditions that would not be acceptable for a permanent, long-term device such as the primary pump 330. In some cases, auxiliary device 268 after operation can be replaced with another auxiliary device.

Figure 5 illustrates an auxiliary negative pressure wound therapy system 1000. Auxiliary pump (such as, the pump 410) or auxiliary power source (such as, the power source 420) can be housed within an auxiliary housing 1001. The auxiliary housing 1001 can be entirely or partially enclosed within the housing of the primary pump assembly 330. Alternatively, the auxiliary housing 1001 can be disposed outside of the primary housing (e.g., be adjacent to that housing, at least partially supported by that housing, or the like).

Any of the embodiments of the auxiliary negative pressure wound therapy system 1000 disclosed herein can have any one or more of the same or similar components, features, materials, sizes, configurations, and other details of any other system embodiments disclosed or incorporated by reference herein, including the embodiments of the pump assemblies in Figures 1 to 3. The auxiliary negative pressure wound therapy system 1000 can include a switch or a button 1002, illustrated as a play/pause button located, for instance, on the exterior of the housing 1001 of the system. The button 1002 can be configured to activate delivery of therapy by the auxiliary system, switch operation of negative pressure from the pump assembly 330 to the auxiliary pump, or the like. The button 1002 can further be configured to stop, pause, or restart negative pressure wound therapy. Although illustrated as a press button 1002, other types of switches or buttons can be included, such as a touchpad, touch screen, keyboard, and so on.

The auxiliary negative pressure wound therapy system 1000 can have one or more indicators, such as the three indicators 1062, 1064, 1066, for providing various indications as described herein, including indicating that negative pressure wound therapy is being provided by the auxiliary negative pressure wound therapy system. The one or more indicators can be visual indicators, such as one or more LEDs, audible, haptic, tactile, etc., or any combination of such indicators. The auxiliary negative pressure wound therapy system 1000 can have one indicator, two indicators, or four or more indicators. As disclosed herein, such indicators can receive power from the auxiliary power source 420 in order to ensure continued operation if the main power source fails. The auxiliary negative pressure wound therapy system 1000 can have a connector port or inlet 1 150. The auxiliary negative pressure wound therapy system 1000 can operate with or without a canister as described herein. In some cases, the illustrated auxiliary negative pressure wound therapy system 1000 can be a PICO™ system sold by Smith & Nephew. Additional details regarding the negative pressure wound therapy system 1000 are described in U.S. Patent Nos. 8,734,425, 8,905,985; and 9,901,664 each of which is incorporated by reference in its entirety.

Terminology

Many other variations than those described herein will be apparent from this disclosure. For example, depending on the embodiment, certain acts, events, or functions of any of the steps described herein can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, acts or events can be performed concurrently. In addition, different tasks or processes can be performed by different machines or computing systems that can function together. 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. Depending on the embodiment, certain of the steps described above maybe removed, others maybe added. For instance, the various components illustrated 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, 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 described embodiments, and may be defined by claims as presented herein or as presented in the future.

Conditional language used herein, such as, among others,“can,”“might,”“may,” “e.g.,” and the like, 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 states. Thus, such conditional language is not generally intended to imply that features, elements or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements or states 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. Additionally, the words“herein,”“above,” "below," and words of similar import, when used in this application, refer to this application as a whole and not to any particular portions of this application.

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

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. As another example, in certain embodiments, the terms“generally parallel” and “substantially parallel” refer to a value, amount, or characteristic that departs from exactly parallel by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree.

Unless otherwise explicitly stated, articles such as“a” or“an” should generally be interpreted to include one or more described items. Accordingly, phrases such as“a device configured to” are intended to include one or more recited devices. Such one or more recited devices can also be collectively configured to carry out the stated recitations.

The scope of the present disclosure is not intended to be limited by the description of certain embodiments and may be defined by the claims. 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 apparatus, comprising:

a first housing at least partially enclosing a first source of negative pressure and a first power source, the first source of negative pressure configured to supply, via a fluid flow path, negative pressure to a wound covered by a wound dressing, and the first power source configured to provide electrical power to the first source of negative pressure;

a second source of negative pressure and a second power source, the second source of negative pressure configured to supply, via the fluid flow path, negative pressure to the wound, when the first source is not supplying negative pressure to the wound, and the second power source configured to provide electrical power to the second source of negative pressure, the second source of negative pressure being different from the first source of negative pressure, and the second power source being different from the first power source;

a sensor configured to determine at least one condition associated with one or more of the first housing, the first source of negative pressure, the first power source, or fluid flow path; and

a control circuit configured to:

based on determining that the at least one condition satisfies a threshold, determine that the first source of negative pressure is unable to supply negative pressure to the wound; and

in response to the determination, deactivate the first source of negative pressure and activate the second source of negative pressure to supply negative pressure to the wound.

2. The apparatus of any of the preceding claims, wherein the at least one condition is associated with malfunction or potential malfunction ofthe first source of negative pressure or the first power source.

3. The apparatus of any of the preceding claims, wherein the sensor comprises a temperature sensor configured to sense temperature of the first power source, and wherein the threshold corresponds to overheating ofthe first power source.

4. The apparatus of any of the preceding claims, wherein the sensor comprises a pressure sensor configured to sense pressure in the fluid flow path, and wherein the threshold corresponds to overpressure in the fluid flow path.

5. The apparatus of any of the preceding claims, wherein the sensor comprises a moisture sensor configured to sense ingress of liquid into an interior of the first housing, and wherein the threshold corresponds to presence of liquid in the interior of the first housing.

6. The apparatus of any of the preceding claims, wherein the control circuit comprises a comparator.

7. The apparatus of any of the preceding claims, further comprising a second housing at least partially enclosing the second source of negative pressure and the second power source.

8. The apparatus of claim 7, wherein the first housing at least partially encloses the second housing.

9. The apparatus of any of the preceding claims, further comprising a valve positioned in the fluid flow path and fluidically connected to the first and second sources of negative pressure, wherein the control circuit is further configured to operate the valve to switch supply of negative pressure from the first negative pressure source to the second negative pressure source in response to the determination.

10. The apparatus of any of the preceding claims, wherein the second power source is configured to provide electrical power to the control circuit.

1 1. The apparatus of claim 10, wherein the second power source is configured to provide electrical power to the control circuit in response to malfunction or failure of the first power source.

12. The apparatus of any ofthe preceding claims, wherein the sensor comprises a fuse.

13. A method of operating a negative pressure wound therapy apparatus comprising a first housing, the method comprising:

via a fluid flow path, providing from a first source of negative pressure enclosed by the first housing negative pressure to a wound covered by a wound dressing, the first source of negative pressure receiving electrical power from a first power source enclosed by the first housing; by a sensor, detecting at least one condition associated with one or more of the first housing, the first source of negative pressure, the first power source, or fluid flow path; and

by a control circuit:

based on determining that the at least one condition detected by the sensor satisfies a threshold, determining that the first source of negative pressure is unable to supply negative pressure to the wound; and

in response to the determination, deactivating the first source of negative pressure and activating a second source of negative pressure to supply negative pressure to the wound via the fluid flow path, the second source of negative pressure receiving power from a second power source different from the first power source.

14. The method of any of the preceding claims, wherein the at least one condition is associated with malfunction or potential malfunction ofthe first source of negative pressure or the first power source.

15. The method of any of the preceding claims, wherein the sensor is configured to sense temperature of the first power source, and wherein the threshold corresponds to overheating ofthe first power source.

16. The method of any of the preceding claims, wherein the sensor is configured to sense pressure in the fluid flow path, and wherein the threshold corresponds to overpressure in the fluid flow path.

17. The method of any of the preceding claims, wherein the sensor is configured to sense ingress of liquid into an interior of the first housing, and wherein the threshold corresponds to presence of liquid in the interior of the first housing.

18. The method of any ofthe preceding claims, wherein the control circuit comprises a comparator.

19. The method of any of the preceding claims, wherein the apparatus further comprises a second housing at least partially enclosing the second source of negative pressure and the second power source.

20. The method of claim 19, wherein the first housing at least partially encloses the second housing.

21. The method of any of the preceding claims, wherein activating the second source of negative pressure comprises switching supply of negative pressure from the first negative pressure source to the second negative pressure source.

22. The method of claim 21 , wherein switching supply of negative pressure comprises operating a valve.

23. The method of any of the preceding claims, wherein the control circuit receives power from the second power source.

24. The method of claim 23, wherein the control circuit receives power from the second power source in response to malfunction or failure of the first power source.

25. The method of any of the preceding claims, wherein the sensor comprises a fuse.