Apparatus and method for negative pressure wound therapy

Abstract

The invention relates to an apparatus and a method for negative pressure wound therapy. Disclosed herein are several embodiments of negative pressure appliances and methods of treating wounds using the negative pressure appliances. Some embodiments relate to an improved fluid connector or suction adapter for connection to a wound site having a blow-by channel separate from a suction channel.

Description

[0001] This invention is a divisional application, the application number of the parent application is 201980040084.2, the application date is July 8, 2019, and the name of the invention is “Device and method for negative pressure wound therapy”. Technical Field

[0002] Embodiments of the present disclosure relate to methods and apparatus for dressing and treating wounds with reduced pressure therapy or topical negative pressure (TNP) therapy. In particular, but not limited to, embodiments disclosed herein relate to negative pressure therapy devices, methods for controlling the operation of TNP systems, and methods of using TNP systems. Background Art

[0003] Many different types of wound dressings are known for aiding the healing process of humans or animals. 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 also referred to as vacuum-assisted closure, negative pressure wound therapy (NPWT) or reduced pressure wound therapy, is widely recognized as a beneficial mechanism for improving wound healing rates. This therapy is suitable for a wide range of wounds, such as incisions, open wounds, abdominal wounds, etc.

[0004] TNP therapy helps to close and heal wounds by reducing tissue edema, promoting blood flow, stimulating granulation tissue formation, removing excess exudate, and can reduce bacterial load and, therefore, reduce wound infection. Furthermore, TNP therapy allows the wound to be less disturbed by external factors, promoting faster healing. Summary of the invention

[0005] Embodiments of the invention disclosed herein relate to devices, systems, apparatuses, and methods for negative pressure wound therapy.

[0006] According to some embodiments, there is provided an apparatus for providing negative pressure to a wound site, the apparatus comprising:

[0007] a top layer, a bottom layer, and a middle layer, wherein each layer is constructed of a flexible, liquid-impermeable material and adhered to one another, wherein each of the layers has a proximal end and a distal end and an elongated portion extending between the proximal end and the distal end;

[0008] an upper fluid pathway, the upper fluid pathway at least partially defined between the top layer and the middle layer, the upper fluid pathway having a proximal end and a distal end, wherein the upper fluid pathway includes an upper channel spacer layer positioned between the upper layer and the middle layer, and wherein the upper fluid pathway is configured to provide air from an air leak toward the distal end of the upper fluid pathway;

[0009] a lower fluid passageway, the lower fluid passageway being at least partially defined between the middle layer and the bottom layer, the lower fluid passageway being configured to be in fluid communication with a negative pressure source, the lower fluid passageway comprising a lower channel spacer layer located between the middle membrane layer and the lower membrane layer; and

[0010] A first opening and a second opening in a distal end of the bottom layer, wherein the first opening is spaced apart from the second opening, wherein the first opening is fluidly connected to the upper fluid passageway and the second opening is fluidly connected to the lower fluid passageway.

[0011] The device in the previous paragraph or other embodiments may include one or more of the following features. In some embodiments, the upper channel spacer layer may include foam and / or the lower channel spacer layer may include a 3D knitted or 3D fabric material. In some embodiments, each of the top layer and the bottom layer may have an enlarged distal end. The enlarged ends of the top layer and the bottom layer may be rectangular and / or form a teardrop shape. In some embodiments, the bottom layer may be attached to an applicator and / or configured to be attached to a cover cloth. The applicator may include two orifices placed directly below the first opening and the second opening. In some embodiments, the air leak may be disposed near the proximal end of the upper fluid passage, and / or the air leak may include a filter. In some embodiments, the upper fluid passage and the lower fluid passage may be fluidically separated from each other. The first opening may be closer to the distal end of the bottom layer than the second opening. The distal end of the intermediate layer may be adjacent to the distal ends of the top layer and the bottom layer. In some embodiments, the device may further include a connector connected to the proximal fluid of the lower channel spacer layer.

[0012] According to some embodiments, there is provided an apparatus for providing negative pressure to a wound site, the apparatus comprising:

[0013] an elongated bridge having a proximal end and a distal end, the elongated body comprising a first fluid passage configured to provide negative pressure to the wound site and a second fluid passage configured to provide an air leak toward the wound site; and

[0014] an applicator at a distal end of the elongated bridge, the applicator comprising a first opening and a second opening spaced apart from the first opening;

[0015] Wherein the first fluid passage is fluidly connected to the first opening, and the second fluid passage is fluidly connected to the second opening.

[0016] The device in the previous paragraph or other embodiments may include one or more of the following features. In some embodiments, each of the first fluid pathway and the second fluid pathway may include a deformable spacer. The deformable spacer of the first fluid pathway may include a 3D knitted or 3D fabric material, and / or the deformable spacer layer of the second fluid pathway includes foam. In some embodiments, the second fluid pathway may be placed above the first fluid pathway. Alternatively, the first fluid pathway and the second fluid pathway may be placed side by side. In some embodiments, the first fluid pathway and the second fluid pathway may be fluidly separated from each other within an elongated bridge. The first fluid pathway and the second fluid pathway may be separated by a fluid-impermeable layer. In some embodiments, the applicator may be configured to attach to a drape. The first opening may be closer to the distal end of the applicator than the second opening. The device may further include an adhesive disposed on the wound-facing side of the applicator. In some embodiments, an air leak may be provided via an opening disposed near the proximal end of the elongated bridge. The air leak may include a filter.

[0017] According to some embodiments, there is provided a method of operating a negative pressure wound therapy device, the method comprising:

[0018] determining a total flow rate in a fluid flow path fluidly coupling a source of negative pressure to a wound dressing placed over a wound, wherein the wound dressing is fluidly connected to a leak path configured to provide gas from a controlled leak port to the wound dressing, wherein the leak path extends along the fluid flow path but is fluidly separated from the fluid flow path;

[0019] In response to monitoring the total flow rate, providing an indication of at least one operating status by:

[0020] providing an indication that an obstruction condition exists in the fluid flow path in response to determining that the total flow rate does not satisfy a flow threshold;

[0021] providing an indication that a normal operating condition exists in response to determining that the total flow rate satisfies the flow threshold,

[0022] The method is performed by a controller of the negative pressure wound therapy device.

[0023] The method in the previous paragraph or other embodiments may include one or more of the following features. In some embodiments, the flow threshold may correspond to an expected flow rate in the fluid flow path. The expected flow rate may correspond to the flow rate in the fluid path under normal operating conditions. In some embodiments, determining the total flow rate may include measuring the speed of a motor operating the negative pressure source. In some embodiments, the method may further include measuring a first plurality of motor speeds during a first time period and averaging the first plurality of motor speeds, the average indicating the flow rate.

[0024] According to some embodiments, there is provided a method of treating a wound, the method comprising:

[0025] A suction adapter is provided, the suction adapter comprising:

[0026] an elongated bridge portion having a proximal end and a distal end, the elongated bridge portion including a first fluid passage configured to provide negative pressure to a wound site and a second fluid passage configured to provide an air leakage port toward the wound site;

[0027] an applicator at a distal end of the elongated bridge, the applicator comprising a first opening and a second opening spaced apart from the first opening;

[0028] wherein the first fluid passage is fluidly connected to the first opening, and the second fluid passage is fluidly connected to the second opening;

[0029] positioning the first and second openings of the applicator over one or more apertures in a drape covering the wound;

[0030] sealing the suction adapter to the drape; and

[0031] Negative pressure is applied to the wound through the suction adapter, wherein air is drawn through the leak toward the wound site, under the drape through the second opening, and through the first opening to the first fluid pathway.

[0032] The method in the previous paragraph or other embodiments may include one or more of the following features. In some embodiments, the one or more orifices in the cover cloth may include a first orifice and a second orifice, and the positioning may include aligning the first opening of the applicator with the first orifice of the cover cloth, and aligning the second opening of the applicator with the second orifice of the cover cloth.

[0033] Other embodiments of devices, apparatuses, kits, and related methods for providing negative pressure to a wound site are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A reduced pressure wound treatment system is shown according to some embodiments.

[0035] Figure 2 A pump assembly and canister are shown according to some embodiments.

[0036] Figure 3 A schematic diagram of the electrical components of a pump assembly according to some embodiments is shown.

[0037] Figure 4AAn embodiment of a negative pressure wound therapy system including a pump is shown, and a flexible suction adapter is shown applied to a wound.

[0038] Figure 4B Shows Figure 4A An embodiment wherein a flexible suction adapter has been placed over the wound.

[0039] Figure 5A An isometric view of a flexible suction adapter that can be used with a negative pressure wound therapy system is shown.

[0040] Figure 5B Shows Figure 5A Exploded view of the flexible suction adapter.

[0041] Figure 5C Shows Figure 5B Close up view of the proximal end of the flexible suction adapter.

[0042] Figure 5D Shows Figure 5A Close-up cross-sectional view of the proximal end of the flexible suction adapter.

[0043] Figure 5E Shows Figure 5A Top view of the flexible suction adapter.

[0044] Fig. 5F Shows Figure 5A Side view of the flexible suction adapter.

[0045] Figure 5G Shows Figure 5A Bottom view of the flexible suction adapter.

[0046] Figure 6 An exploded view of an alternative flexible suction adapter is shown.

[0047] Fig. 7A Shown is a top view of a 3D fabric that may be used in a negative pressure wound therapy device.

[0048] Figure 7B Shows Fig. 7A Bottom view of the 3D fabric.

[0049] Figure 7C Shows Fig. 7A Side cross-sectional view of the 3D fabric.

[0050] Fig. 8A -B shows a device having two or more protrusions and can be connected to Figure 5A An embodiment of a connector for a suction adapter.

[0051] Fig.9AShown is an exploded view of a flexible suction adapter that can be used with a negative pressure wound therapy system.

[0052] Fig. 9B Shows Fig.9A Top view of the flexible suction adapter.

[0053] Fig. 9C Shows Fig.9A Cross-sectional view of a flexible suction adapter.

[0054] Fig.10 A diagram of a system for applying negative pressure is shown in accordance with some embodiments.

[0055] Fig.11A A negative pressure wound therapy system including a negative pressure device is shown according to some embodiments, and a pair of flexible suction adapters applied to a wound is shown.

[0056] Fig. 11B Shows Fig.11A An embodiment wherein a flexible suction adapter has been placed over the wound.

[0057] Fig.12 A diagram of a system for applying negative pressure is shown in accordance with some embodiments.

[0058] Fig.13 A flow chart of a process for determining and indicating one or more operating states is shown in accordance with some embodiments.

[0059] Fig.14 A flow chart of a process for determining and indicating one or more operating states is shown in accordance with some embodiments. DETAILED DESCRIPTION

[0060] Overview

[0061] Embodiments disclosed herein relate to equipment, systems, devices and methods for treating wounds with reduced pressure. As used herein, a reduced pressure level or negative pressure level (e.g., -XmmHg) represents a pressure level relative to normal ambient atmospheric pressure, which may correspond to 760mmHg (or 1atm, 29.93inHg, 101.325kPa, 14.696psi, etc.). Therefore, a negative pressure value of -XmmHg reflects an absolute pressure of X mmHg lower than 760mmHg, or in other words, an absolute pressure of (760-X)mmHg. In addition, a negative pressure that is "less" or "smaller" than X mmHg corresponds to a pressure closer to atmospheric pressure (e.g., -40mmHg is smaller than -60mmHg). A negative pressure that is "more" or "larger" than -XmmHg corresponds to a pressure further away from atmospheric pressure (e.g., -80mmHg is larger than -60mmHg). In some embodiments, the local ambient atmospheric pressure is used as a reference point, which local atmospheric pressure may not necessarily be, for example, 760 mmHg.

[0062] Embodiments of the present disclosure are generally applicable to topical negative pressure (TNP) or reduced pressure therapy systems. In short, negative pressure wound therapy helps to close and heal many forms of "difficult to heal" wounds by reducing tissue edema, promoting blood flow and granulation tissue formation, or removing excess exudate, and can reduce bacterial load (and therefore reduce infection risk). In addition, the therapy allows the wound to be less disturbed, thereby healing faster. TNP therapy systems can also assist in the healing of surgically closed wounds by removing fluids. In some embodiments, TNP therapy helps stabilize tissue at the apposed closed position. Additional beneficial uses of TNP therapy can be found in grafts and flaps, where removal of excess fluid is important and close proximity of the graft to the tissue is required to ensure tissue viability.

[0063] Negative pressure system

[0064] Figure 1 One embodiment of a negative pressure or reduced pressure wound therapy (or TNP) system 100 is shown, which includes a wound filler 130 placed in a wound cavity 110, which is sealed by a wound cover 120. The wound filler 130 and the wound cover 120 in combination can be referred to as a wound dressing. A flow path 140, such as a single-lumen or multi-lumen tube or conduit, is connected to the wound cover 120 having a negative pressure wound therapy device, which is configured to provide reduced pressure (e.g., a pump assembly 150). The wound cover 120 can be in fluid communication with the wound cavity 110. In any system embodiments disclosed herein, such as Figure 1In the illustrated embodiment, the pump assembly may be a canisterless pump assembly (meaning that the exudate is collected in the wound dressing or is transferred via the tube 140 to be collected at another location). However, any pump assembly embodiment disclosed herein may be configured to include or support a canister. In addition, in any system embodiment disclosed herein, any pump assembly embodiment may be mounted to or supported by the dressing, or adjacent to the dressing. The wound filler 130 may be of any suitable type, such as a hydrophilic or hydrophobic foam, gauze, an inflatable bag, and the like. The wound filler 130 may fit the wound cavity 110 so that it substantially fills the cavity. The wound cover 120 may provide a substantially fluid-impermeable seal over the wound cavity 110. The wound cover 120 may have a top side and a bottom side, and the bottom side is adhesively (or in any other suitable manner) sealed to the wound cavity 110. The conduit 140 or lumen or any other conduit or lumen disclosed herein may be formed of polyurethane, PVC, nylon, polyethylene, silicone, or any other suitable material.

[0065] Some embodiments of the wound cover 120 may have a port (not shown) configured to receive an end of a conduit 140. In other embodiments, the conduit 140 may otherwise pass through or under the wound cover 120 to supply reduced pressure to the wound cavity 110 so as to maintain a desired reduced pressure level in the wound cavity. The conduit 140 may be any suitable article configured to provide an at least substantially sealed fluid flow path between the pump assembly 150 and the wound cover 120 so as to supply the reduced pressure provided by the pump assembly 150 to the wound cavity 110. The wound cover 120 and the wound filler 130 may be provided as a single article or in the form of an integral single unit. In some embodiments, a wound filler is not provided, and the wound cover itself may be considered a wound dressing. The wound dressing may then be connected to a negative pressure source, such as a pump assembly 150, via the conduit 140. The pump assembly 150 may be miniaturized or portable, but a larger conventional pump may also be used.

[0066] The wound cover 120 may be located above a wound site to be treated. The wound cover 120 may form a substantially sealed cavity or enclosure above the wound site. In some embodiments, the wound cover 120 may be configured to have a membrane having a high water vapor permeability to enable excess fluid to evaporate, and may have a superabsorbent material contained therein to safely absorb wound exudate. It should be appreciated that reference is made to wounds throughout the specification. In this sense, it should be understood that the term wound should be broadly interpreted as, and encompasses, open wounds and closed wounds, where the skin is torn, cut or punctured, or where trauma has caused a contusion, or any other surface or other condition or defect on the patient's skin, or those wounds that would benefit from reduced pressure treatment. Thus, a wound is broadly defined as any damaged tissue area that may or may not produce fluid. Examples of such wounds include, but are not limited to, acute wounds, chronic wounds, surgical and other incisions, subacute and dehiscent wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure sores, ostomies, surgical wounds, traumatic and venous ulcers, etc. The components of the TNP system described herein may be particularly suitable for incisional wounds that shed small amounts of wound exudate.

[0067] Some embodiments of the system are designed to operate without the use of an exudate tank. Some embodiments can be configured to support an exudate tank. In some embodiments, the pump assembly 150 and tubing 140 are configured so that the tubing 140 can be quickly and easily removed from the pump assembly 150, which can facilitate or improve the process of dressing or pump replacement (if necessary). Any of the pump embodiments disclosed herein can be configured to have any suitable connection between the tubing and the pump.

[0068] In some embodiments, pump assembly 150 may be configured to deliver a negative pressure of about -80 mmHg, or about -20 mmHg to -200 mmHg. It should be noted that these pressures are relative to normal ambient atmospheric pressure, therefore, -200 mmHg will actually be about 560 mmHg. The pressure range may be between about -40 mmHg and -150 mmHg. Alternatively, a pressure range of up to -75 mmHg, up to -80 mmHg, or exceeding -80 mmHg may be used. In addition, a pressure range of less than -75 mmHg may be suitable. Alternatively, pump assembly 150 may supply a pressure range exceeding about -100 mmHg or even 150 mmHg. In some embodiments, pump assembly 150 is configured to provide continuous or intermittent negative pressure therapy. Continuous therapy can be delivered 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. The low set point can be set 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. The high set point can be set 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, a negative pressure at a low set point can be delivered for a first duration, and after the first duration expires, a negative pressure at a high set point can be delivered for a second duration. After the second duration expires, a negative pressure at a low set point can be delivered. The first and second time durations can be the same or different values. The first and second durations can be selected from the following ranges: less than 2 minutes, 2 minutes, 3 minutes, 4 minutes, 6 minutes, 8 minutes, 10 minutes or more than 10 minutes. In some embodiments, switching between a low set point and a high set point and switching between a high set point and a low set point can be performed according to a stepped waveform, a square waveform, a sine waveform, etc.

[0069] In some embodiments, the TNP system 100 may include multiple wound dressings connected to the pump assembly 150. The performance and wound healing capabilities (e.g., fluid management) of a TNP system having multiple wound dressings with a pump assembly 150 may equal or exceed the performance and wound healing capabilities of a standard single wound dressing having a single pump setup.

[0070] In operation, the wound filler 130 is inserted into the wound cavity 110, and the wound cover 120 is placed to seal the wound cavity 110. The pump assembly 150 provides a source of 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 sucked through the conduit 140 and can be stored in a tank. In some embodiments, the fluid is absorbed by the wound filler 130 or one or more absorbent layers (not shown).

[0071] Wound dressings that can be used 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. Any dressing described herein can be used with a Renasys soft port connector from Smith and Nephew or an interface between the dressing and the pump assembly. For example, a Renasys soft port connector can be positioned in the flow path 140 and used as a port for the wound dressing. In other embodiments, other suitable wound dressings can be used.

[0072] Pump Assemblies and Tanks

[0073] Figure 2A front view 200 of a pump assembly 230 and a canister 220 according to some embodiments is shown. As shown, the pump assembly 230 and the canister are connected to form a TNP device or system. The pump assembly 230 includes one or more indicators, such as a visual indicator 202 configured to indicate an alarm, and a visual indicator 204 configured to indicate the state of the TNP system. The indicators 202 and 204 can be configured to prompt a user (such as a patient or a medical care provider) a variety of operating or fault states of the system, including prompting the user normal or correct operating state, pump failure, power supply to the pump or power failure, detection of a leak in the wound cover or flow path, suction blockage, no flow state, canister full state, or any other similar or suitable state or combination thereof. The pump assembly 230 may include additional indicators. The pump assembly may use a single indicator or multiple indicators. Any suitable indicator may be used, such as a visual, audio, tactile indicator, etc. The indicator 202 may be configured to signal an alarm condition, such as a canister full, low power, catheter 140 disconnected, a seal in wound seal 120 broken, etc. The indicator 202 may be configured to display a flashing red light to attract the user's attention. The indicator 204 may be configured to signal the status of the TNP system, such as treatment delivery is normal, a leak is detected, etc. The indicator 204 may be configured to display one or more different colors of light, such as green, yellow, etc. For example, a green light may be emitted when the TNP system is operating properly, and a yellow light may be emitted to indicate a warning.

[0074] The pump assembly 230 includes a display or screen 206 mounted in a recess 208 formed in the housing of the pump assembly. The display 206 may be a touch screen display. The display 206 may support playback of audio-visual (AV) content, such as an instructional video. As described below, the display 206 may be configured to present multiple screens or graphical user interfaces (GUIs) for configuring, controlling, and monitoring the operation of the TNP system. The pump assembly 230 includes a gripping portion 210 formed in the housing of the pump assembly. The gripping portion 210 may be configured to assist a user in holding the pump assembly 230, for example, during removal of the tank 220. The tank 220 may be replaced by another tank, for example, when the tank 220 is filled with fluid.

[0075] The pump assembly 230 includes one or more keys or buttons 212 configured to allow a user to operate and monitor the operation of the TNP system. As shown, buttons 212a, 212b, and 212c are included. Button 212a can be configured as a power button to turn on / off the pump assembly 230. Button 212b can be configured as a play / pause button for delivering negative pressure therapy. For example, pressing button 212b can cause the therapy to start, and then pressing button 212b can cause the therapy to pause or end. Button 212c can be configured to lock the display 206 or button 212. For example, button 212c can be pressed so that the user does not inadvertently change the delivery of the therapy. Button 212c can be pressed to unlock the control. In other embodiments, additional buttons can be used, or one or more of the buttons 212a, 212b, or 212c shown can be omitted. Multiple key presses or key sequence can be used to operate the pump assembly 230.

[0076] The pump assembly 230 includes one or more locking notches 222 formed in the cover. In the illustrated embodiment, two locking notches 222 may be formed on the side of the pump assembly 230. The locking notches 222 may be configured to allow the canister 220 to be attached and detached using one or more canister locks 221. The pump assembly 230 includes an air outlet 224 for allowing air removed from the wound cavity 110 to escape. The air entering the pump assembly may pass through one or more suitable filters, such as an antibacterial filter. This may maintain the reusability of the pump assembly. The pump assembly 230 includes one or more belt mounts 226 for connecting a carrying belt to the pump assembly 230 or for attaching a bracket. In the illustrated embodiment, two belt mounts 226 may be formed on the side of the pump assembly 230. In some embodiments, various features are omitted, or various additional features are added to the pump assembly 230.

[0077] The tank 220 is configured to hold fluid (e.g., exudate) removed from the wound cavity 110. The tank 220 includes one or more latches 221 for attaching the tank to the pump assembly 230. In the illustrated embodiment, the tank 220 includes two latches 221 on the side of the tank. The exterior of the tank 220 may be formed of frosted plastic so that the tank is substantially opaque and the tank and the contents are substantially hidden from the plan view. The tank 220 includes a gripping portion 214 formed in the shell of the tank. The gripping portion 214 may be configured to allow the user to hold the pump assembly 220, for example, during the removal of the tank from the device 230. The tank 220 includes a substantially transparent window 216, which may also include a volume scale. For example, the 300 mL tank 220 shown includes scales of 50 mL, 100 mL, 150 mL, 200 mL, 250 mL, and 300 mL. Other embodiments of the tank may hold different volumes of fluid and may include different scales. For example, the tank may be a 800 mL tank. The canister 220 includes a tubing passage 218 for connection to the catheter 140. In some embodiments, one or more of these features are omitted, such as the gripping portion 214, or various additional features are added to the canister 220. Any of the disclosed canisters may include or omit a curing agent.

[0078] Electronics and Software

[0079] Figure 3 A schematic diagram 300 of electrical components of a pump assembly (such as pump assembly 230) according to some embodiments is shown. The electrical components are operable to accept user input, provide output to the user, operate the pump system and the TNP system, provide network connections, and the like. The electrical components may be mounted on one or more printed circuit boards (PCBs). As shown, the pump assembly may include multiple processors. It may be advantageous to utilize multiple processors so that various tasks are allocated or assigned to different processors. The first processor may be responsible for user activities, and the second processor may be responsible for controlling the pump. In this way, the activities of controlling the pump that may require a higher level of response (corresponding to a higher level of risk) can be offloaded to a dedicated processor, and thus will not be interrupted by the user interface task, which may take longer to complete because of interacting with the user.

[0080] The pump assembly may include a user interface processor or controller 310 configured to operate one or more components for accepting user input and providing output to the user, such as display 206, button 212, etc. The pump assembly input and output from the pump assembly may be controlled by an input / output (I / O) module 320. For example, the I / O module may receive data from one or more ports, such as serial, parallel, hybrid ports, etc. The processor 310 also receives data from one or more expansion modules 360 and provides data to one or more expansion modules, such as one or more USB ports, SD ports, compact disk (CD) drives, DVD drives, FireWire ports, Thunderbolt ports, PCI Express ports, etc. The processor 310, along with other controllers or processors, stores data in one or more memory modules 350, which may be internal and / or external to the processor 310. Any suitable type of memory may be used, including volatile or non-volatile memory, such as RAM, ROM, magnetic memory, solid-state memory, magnetoresistive random access memory (MRAM), etc.

[0081] In some embodiments, the processor 310 can be a general purpose processor, such as a low power processor. In other embodiments, the processor 310 can be a dedicated processor. The processor 310 can be configured as a "central" processor in the electronic architecture of the pump assembly, and the processor 310 can coordinate the activities of other processors, such as the pump control processor 370, the communication processor 330, and one or more additional processors 380 (e.g., a processor for controlling the display 206, a processor for controlling the button 212, etc.). The processor 310 can run a suitable operating system, such as Linux, Windows CE, VxWorks, etc.

[0082] The pump control processor 370 can be configured to control the operation of the negative pressure source or pump 390. The pump 390 can be a suitable pump, such as a diaphragm pump, a peristaltic pump, a rotary pump, a rotary vane pump, a vortex pump, a screw pump, a liquid ring pump, a pump operated by a piezoelectric transducer (e.g., a diaphragm pump), a voice coil pump, etc. The pump control processor 370 can measure the pressure in the fluid flow path using data received from one or more pressure sensors, calculate the fluid flow rate and control the pump. The pump control processor 370 can control an actuator such as a pump motor so that a required negative pressure level is achieved in the wound cavity 110. The required negative pressure level can be a pressure set or selected by a user. In various embodiments, the pump control processor 370 controls the pump actuator (e.g., a pump motor) using pulse width modulation (PWM). The control signal for driving the pump actuator can be a PWM signal with a duty cycle of 0-100%. The pump control processor 370 can perform flow rate calculations and detect various conditions in the flow path. The pump control processor 370 can transmit information to the processor 310. The pump control processor 370 may include internal memory or may utilize the memory 350. The pump control processor 370 may be a low power processor.

[0083] The communication processor 330 can be configured to provide a wired or wireless connection. The communication processor 330 can use one or more antennas 340 to send and receive data. The communication processor 330 can provide one or more of the following types of connections: global positioning system (GPS) technology, cellular connection (e.g., 2G, 3G, LTE, 4G), WiFi connection, Internet connection, etc. The connection can be used for various activities, such as pump component location tracking, asset tracking, compliance monitoring, remote selection, log upload, alarm and other operating data, and adjustment of treatment settings, software or firmware upgrades, etc. The communication processor 330 can provide dual GPS / cellular functions. The cellular function can be, for example, a 3G function. In this case, if the GPS module cannot establish a satellite connection due to various factors including atmospheric conditions, building or terrain interference, satellite geometry, etc., the 3G network connection can be used to determine the device location, such as by using unit identification, triangulation, forward link timing, etc. The pump component can include a SIM card, and SIM-based location information can be obtained.

[0084] The communication processor 330 may communicate information to the processor 310. The communication processor 330 may include internal memory, or may utilize the memory 350. The communication processor 330 may be a low power processor.

[0085] In some embodiments, the pump assembly can track and store various data, such as one or more of positioning data, treatment parameters, logs, device data, etc. The pump assembly can track and record treatment and other operational data. The data can be stored, for example, in memory 350.

[0086] In some embodiments, using the connection provided by the communication processor 330, the device can upload any data stored, maintained and / or tracked by the pump assembly. For example, the following information can be uploaded to a remote computer or server: an activity log, including treatment delivery information such as treatment time; an alarm log, including the type of alarm and the time it occurred; an error log, including internal error information, transmission errors, etc.; treatment duration information, which can be calculated once an hour, once a day, etc.; total treatment time, including the duration of treatment since the first application of a particular treatment program or multiple programs; lifetime treatment information; device information, such as serial number, software version, battery level, etc.; device location information; patient information; etc. The device can also download various operational data, such as treatment selections and parameters, firmware and software patches and upgrades, etc. The pump assembly can provide Internet browsing capabilities using one or more browser programs, email programs, application software (e.g., applications), etc.

[0087] In some embodiments, the communication processor 330 can use the antenna 340 to transmit the location of the pump assembly, such as the location of the housing of the pump assembly, to other devices near the pump assembly (e.g., within 10, 20, or 50 meters, etc.). The communication processor 330 can perform unidirectional or bidirectional communication with other devices depending on the implementation. The communication transmitted by the communication processor 330 may include identification information to uniquely identify the pump assembly relative to one or more other pump assemblies that are also near the pump assembly. For example, the identification information may include a serial number or a value derived from the serial number. The signal strength of the communication transmitted by the communication processor 330 can be controlled (e.g., maintained at a constant or substantially constant level) to enable another device to determine the distance to the pump assembly, such as the distance between the device and the pump assembly.

[0088] In some embodiments, the communication processor 330 can communicate with other devices in the vicinity of the pump assembly so that the communication processor 330 itself can determine the distance from the pump assembly to the other devices. In such embodiments, the communication processor 330 can track and store an indication of the distance from the pump assembly to the other devices or changes in the distance over time, and the communication processor 330 can later provide this information to the other devices. For example, the communication processor 330 can determine the duration that the pump assembly has been removed from the coverage area of ​​the device, and then report this time to the device when it returns to the coverage area.

[0089] Flexible suction adapter

[0090] Figure 4A-6 Shows something like Figure 1An embodiment of a negative pressure wound therapy system 5501 of the embodiment shown in . Here, the system 5501 may include a flexible suction adapter 5500 having a bridge portion 5502 with a proximal end 5503 and a distal end 5505, and an applicator 5520 at the distal end 5505 of the bridge portion 5502 forming the flexible suction adapter 5500. Figure 4B As shown, the connector 5504 is preferably disposed at the proximal end 5503 of the bridging portion 5502 so as to connect to at least one of the channels 5512 and / or 5516. A cap 5536 may be provided with the system 5501 (and in some cases may be attached to the connector 5504 as shown). The cap 5536 may be used to prevent fluid from leaking out of the proximal end 5503. The system 5501 may include a negative pressure source, such as a pump or negative pressure unit 5534 capable of supplying negative pressure. The pump also preferably includes a tank or other container for storing wound exudate and other fluids that can be removed from the wound. In some embodiments, the pump 5534 may be about Figure 2 The pump 200 described above. In some embodiments, this pump 5534 can be a RENASYS GO pump such as sold by Smith & Nephew. The pump 5534 can be connected to the connector 5504 via a tube 5540. In use, the applicator 5520 is placed above the orifice 5535 formed in the cover cloth 5531, and the cover cloth is placed above the appropriately prepared wound 5530, which in some cases can be filled with a wound packing material such as foam or gauze. Subsequently, with the pump 5534 connected to the connector 5504 via a tube 5540, the pump is activated, thereby supplying negative pressure to the wound. Negative pressure can be applied until the desired level of healing of the wound 5530 is reached.

[0091] In some embodiments, the bridging portion 5502 may include an upper channel layer 5512 positioned between the upper layer 5510 and the middle layer 5514, wherein the lower channel layer 5516 is positioned between the middle layer 5514 and the bottom layer 5518. Preferably, the layers 5510, 5514, and 5518 have elongated portions extending between proximal and distal ends and may be comprised of a fluid-impermeable material, such as a polymer, such as polyurethane. Of course, it should be appreciated that the layers 5510, 5514, and 5518 may each be comprised of a different material, including a semi-permeable material. In some embodiments, one or more of the layers 5510, 5514, and 5518 may be at least partially transparent. As shown in FIG. Figure 5B, the upper layer 5510 and the lower layer 5518 can be curved, rounded, or convex outwardly over a majority of their lengths. During assembly, for example, the layers 5510, 5514, and 5518 can be clamped together to weld or adhere the layers together. In doing so, the proximal ends of the channels 5512 and 5516 can be sandwiched between these layers, thereby partially compressing the proximal ends of the channels 5512, 5516 and stretching the layers 5510, 5514, 5518 over these aforementioned proximal ends. Of course, the proximal ends of the material used in the bridge portion 5502 may not necessarily be rounded or curved; as Figure 6 As shown, they can remain substantially square and straight.

[0092] The upper channel layer 5512 and the lower channel layer 5516 are preferably elongated layers extending from the proximal end 5503 to the distal end 5505, and each may preferably include a porous material, including, for example, an open-cell foam, such as polyethylene or polyurethane. In some embodiments, one or more of the upper channel layer 5512 and the lower channel layer 5516 may be made of a fabric (e.g., a knitted or woven spacer fabric (e.g., a knitted polyester 3D fabric, Baltex 7970.RTM. or Gehring 879.RTM.)) or a nonwoven material. Suitable materials may also include terry knit or terry woven materials. The fibers may not necessarily be woven, and may include felting and flocking (including materials such as Flotex.RTM) fiber materials. The selected material is preferably suitable for guiding wound exudate away from the wound through the channel, and for transmitting negative pressure and / or exhaust air to the wound site, and as described below, may also impart a degree of anti-kink or occlusion to the channel layers 5512 and 5516. In one embodiment, the upper channel layer 5512 may include an open cell foam, such as polyurethane, and the lower channel layer may include a fabric as described herein. In another embodiment, the upper channel layer is optional and the system may instead have an open upper channel. Figure 5B In the illustrated embodiment, the upper channel layer 5512 may have a curved, rounded, or upwardly convex upper surface and a substantially flat lower surface, and the lower channel layer 5516 may have a curved, rounded, or downwardly convex lower surface and a substantially flat upper surface.

[0093] In some embodiments, the fabric may have a three-dimensional (3D) structure, wherein one or more types of fibers form a structure in which the fibers extend in all three dimensions. In some cases, such fabrics can help wicking, transmission fluid and / or transmission negative pressure. In order to prevent the channel 5512 and / or 5516 from shifting or twisting when encapsulated in the system 5501 (which may damage the performance of the corresponding channel under negative pressure), in some embodiments, the channel 5512 and / or 5516 may be preferably adhered or otherwise fixed to one or more of the layers 5510, 5514 and 5518. In certain embodiments, these materials remain open and can transmit negative pressure to the wound area at a typical pressure used in negative pressure therapy (e.g., between 40 and 150 mmHg, but higher and lower values ​​are also possible). In some embodiments, the fabric may include several material layers stacked or laminated on each other, which may be used to prevent the channel 5516 from collapsing under the application of negative pressure in some cases. In other embodiments, the fabric used in channel 5516 may be between 1.5 mm and 6 mm; more preferably, the fabric may be between 3 mm and 6 mm thick, and may include one or several separate layers of fabric. In other embodiments, channel 5512 may be 1.2-3 mm thick, and preferably thicker than 1.5 mm. In addition, and as previously described, the materials used in system 5501 are preferably conformable and soft, which may help avoid pressure sores and other complications that may result from the wound treatment system pressing against the patient's skin. Other examples of 3D fabrics are described in Fig. 7A -C is described below.

[0094] Preferably, the distal ends of layers 5510, 5514, and 5518, and channel layers 5512 and 5516, are enlarged at their distal ends (placed over the wound site), and may form a "teardrop" or other enlarged shape. The distal ends of at least layers 5512, 5514, 5516, and 5518 may also be provided with at least one through-going orifice. This orifice may be used not only to drain wound exudate and apply negative pressure to the wound, but may also be used during manufacture of the device, as the orifices may be used to properly align the respective layers.

[0095] Additional references Figure 5B -C and 6, the channel connector 5506 is provided at the proximal end 5503 of the bridging portion 5502, and the channel connector 5506 is preferably configured to be embedded in the lower channel layer 5516 to create a secure fluid connection. In some embodiments, the channel connector 5506 can be inserted into a prefabricated cavity formed in the channel 5516; Figure 6 As shown in , this cavity can be cut or can be in the form of a groove and tongue joint. In some embodiments, the channel connector 5506 can be the following Fig. 8A-One of the connectors described in B. In the case where one end of the channel connector 5506 is embedded in the lower channel layer 5516, the other end of the channel connector 5506 may be connected to or communicate with the connector tube 5507 in one embodiment, but in some embodiments, the channel connector 5506 may be directly connected to the connector 5504, or additionally directly connected to the tube 5540 connected to the negative pressure source. When the connector tube 5507 is used, the resulting assembly allows the connector 5504 to be attached to the connector tube. Cap 5536, which can be fixed to the suction adapter, for example, via a cap rope 5527, which is fixed with a ring provided on the outer surface of the connector tube 5507. Cap 5536 can be used to cover the end of the suction adapter, for example at the connector 5504, so as to prevent leakage of exudate and other wound fluids. The connector 5504 is preferably configured to be connected to the tube 5540 connected to the negative pressure source. The connector 5504 may, for example, include a lip or other such structure to help secure the connector 5504 to the tube 5540 and / or the cap 5536, but it should be understood that other connector types are possible, including quick disconnect connectors, Luer locks, Christmas trees, and other such connectors.

[0096] The upper layer 5510 may include additional material extending downward, preferably at least the thickness of the bridging portion 5502; this material can then be used to join or weld the other layers to form a fluid-tight seal. More specifically, during assembly, the upper layer 5510 can be attached to the lower layer 5518, such as by melting, welding, or with an adhesive, so as to form a fluid-tight seal (except for the orifices at the distal and proximal ends). Preferably, the middle layer 5514 is attached to the top layer 5510 and the bottom layer 5518. In some embodiments, it may be preferred to attach or join the connector 5504 and / or 5506 and the tube 5507 to at least one of the layers 5510, 5514, 5518 to create a fluid-tight connection. In order to provide a more secure connection, some embodiments may also be provided with a weld 5532 created on the lower layer 5518. The lower channel 5516 may have a hole or orifice created therethrough, which can be used to weld it to the lower layer 5518 via the weld 5532. The welding of the lower channel 5516 to the lower layer 5518 via the weld 5532 produced through the hole 5533 can thus help prevent the various layers and channels from shifting or dislodging. Obviously, it will be understood that other fixing means, such as adhesives, etc., can be used, and such arrangements can also be used in the upper channel 5512.

[0097] In certain embodiments, for example, Figure 5A-6, a controlled air leak 5524 can be provided on the bridging portion 5502, for example at its proximal end. This air leak 5524 may include an opening or channel extending through the upper layer 5510, so that the air leak 5524 is in fluid communication with the upper channel 5512. When suction is applied to the suction adapter 5500, air will enter through the air leak 5524 and move from the proximal end 5503 to the distal end 5505 along the upper channel 5512. Then, through the orifice at the distal end of the through-layers 5512, 5514, 5516 and 5518, the air will be sucked into the lower channel 5516. The air leak 5524 preferably includes a filter 5525. Preferably, the air leak 5524 is located at the proximal end of the bridging portion 5502 to minimize the possibility that wound exudate or other fluids contact and may block or interfere with the air leak 5524 or its filter 5525. In some embodiments, the filter 5525 is a microporous membrane capable of excluding microorganisms and bacteria, and can filter out particles greater than 45 microns. Preferably, the filter 5525 can exclude particles greater than 1.0 microns, and more preferably exclude particles greater than 0.2 microns. Advantageously, some embodiments can provide a filter 5525 that is at least partially chemically resistant to, for example, water, common household liquids such as shampoo, and other surfactants. In some embodiments, applying vacuum to the suction adapter 5500 and / or wiping the exposed outer portion of the filter 5525 again can be sufficient to remove any foreign matter that blocks the filter 5525. The filter 5525 can be composed of a polymer of appropriate resistance such as acrylic acid, polyethersulfone or polytetrafluoroethylene, and can be oleophobic and / or hydrophobic. In some embodiments, the filter 5525 may also include a supporting backing layer, such as a non-woven polyester support. Preferably, the air leak 5524 will supply a relatively constant air flow that will not increase significantly as additional negative pressure is applied to the system 5501. In an embodiment of the suction adapter 5500, as additional negative pressure is applied, the air flow through the leak port 5524 increases, preferably, this increased air flow will be minimized and will not increase proportionally with the negative pressure applied thereto.

[0098] In certain embodiments, a filter 5525 disposed in a controlled leak port 5524 may be used in the system 5501 for use with more dynamic and active patients. For example, when reconnecting to a negative pressure source, a chemically resistant filter may allow the patient to bathe or shower without damaging the function of the filter. Any occlusion or fluid blocking the leak port 5524 may then be cleared by, for example, wiping the filter 5525 or reapplying negative pressure to the suction adapter 5500. Such a system would also have the advantage that if the patient needs to be disconnected from the negative pressure source (e.g., accompanying a bath), the system 5501 and any combined wound dressing material (if present) does not need to be removed and reapplied. This would have significant advantages in terms of improving the cost-effectiveness and ease of use of the present treatment system.

[0099] The suction adapter 5500 is preferably configured to provide a consistent fluid flow even if the suction adapter 5500 is kinked or depressed. For example, when used on a patient, the bridging portion 5502 may become folded onto itself, or the patient may flip, thereby placing his or her weight over at least a portion of the suction adapter 5500. Typically, dressings and fluid connectors of the prior art become obstructed or inefficient in such situations, and may cause complications such as pressure sores in some cases. However, here, certain embodiments provide improved resistance to obstruction when kinked or depressed. Preferably, by employing channel layers 5512 and 5516 as described above, and more preferably by employing a foam channel layer 5512 and a fabric channel layer 5516, the suction adapter 5500 is able to maintain a flow rate of at least 0.08 L / min, and preferably 0.12 L / min, through the leak port 5524 when negative pressure is applied by a negative pressure source. Other embodiments also provide suction adapter 5500 and can handle at least 10L / day or 6.9ml / minute of fluid exudate flowing out from wound site through lower channel 5516. Certain embodiments provide suction adapter 5500, to maintain these flow rates with the weight of for example 1 inch diameter rod pressing down on bridging portion, for example 12kg weight. In certain embodiments, when bridging portion 5502 is twisted to itself with the same weight or for example 4.75kg weight directly placed on folding area, these flow rates are also maintained. Preferably, suction adapter 5500 can withstand folding or kinking in extended time period (for example more than 40 hours), and will not show any degradation of performance (for example, flow rate) compared with its performance before folding or kinking. Preferably, the embodiment of suction adapter 5500 can also transmit and maintain negative pressure at the level of negative pressure near negative pressure source at wound. For example, an acceptable pressure level maintained at the wound may be within +-0.25 mmHg of the negative pressure set at the negative pressure source, wherein the pressure preferably remains at this level for 95% of the time that the suction adapter 5500 applies negative pressure thereto. Acceptable pressure levels may include a range of pressures between 40-120 mmHg, but levels of 200 mmHg have been used successfully.

[0100] Additional references Figures 4A-5B6, the suction adapter 5500 also includes an applicator 5520, which is designed to be placed above the wound site. Preferably, the applicator 5520 includes a flexible layer 5550, such as polyethylene or polyurethane, which has an adhesive layer on the lower (wound-facing) side. Optionally, a protective release layer 5529 can be placed on the adhesive layer, which is removable before use. In some embodiments, due to the flexibility of the layer 5550, a more rigid removable backing layer 5552 can be provided on the upper side of the applicator 5520 to facilitate the handling of the applicator 5520. The applicator 5520 preferably includes an attachment point for the bridge 5502 at the distal end 5505, such as using a section of double-sided adhesive tape 5528. The double-sided adhesive tape 5528 can be protected by an additional protective peeling layer, which is removed before the bridge 5502 is adhered to the applicator 5520. It should be understood that different attachment methods can also be conceived, such as heat sealing, welding or suitable adhesives. Some embodiments may also allow the bridge 5502 and applicator 5520 to be manufactured as a single unit without the need for a separate attachment device. The applicator 5520 preferably includes at least one orifice 5526 through it and is designed to be placed on the wound site, and which can be used to fluidly connect the wound site to a negative pressure source and an air leak, while also serving as a conduit for withdrawing wound exudate from the wound site.

[0101] In use and reference Figure 4A -B, the system 5501 can be used in a manner similar to other embodiments previously disclosed herein, such as with respect to Figure 1 The system 100 described. The wound site 5530 is preferably cleaned and prepared in a suitable manner, and the wound packing material (if necessary) is placed in the wound site, followed by the drape 5531. An orifice 5535 is then created through the drape to the wound site, but some embodiments may have a pre-made orifice 5535. Subsequently, the operator can position the applicator portion 5520 above the orifice 5535. After removing the backing layer 5529 (if present) from the adhesive layer on the underside of the applicator portion 5520, the applicator is sealed to the drape 5531, and the backing layer 5552 (if present) is also removed from the applicator portion 5520. A fluid conduit such as a tube 5540 can then be connected to the connector 5504. The tube 5540 can also be connected to the connector 5504 before the applicator is applied to the wound site. The fluid conduit is connected to a negative pressure source 5534, and a container preferably suitable for containing wound exudate is inserted between the fluid conduit and the negative pressure source. Negative pressure may then be applied to the wound site 5530 until the wound site progresses to the desired level of healing.

[0102] During use of the system 5501, wound exudate from the wound site 5530 is extracted by negative pressure through the lower channel layer 5516. The leak port 5524 allows air to pass through the upper channel layer 5512 into the orifice at the distal end of the penetration layer 5512, 5514, 5516 and 5518. The negative pressure draws the air passing through the upper channel layer back into the lower channel layer 5516 toward the negative pressure source or pump. In some embodiments, the controlled leak port 5524 provides a constant air flow through the suction adapter 5500, which can then be used to determine whether there is a blockage or leak. The cause of the blockage may include, for example, a situation where the lower channel 5516 becomes blocked by wound debris. The cause of the leak may include, for example, an improper seal of the cover cloth on the wound site, or physical damage to the suction adapter 5500, resulting in excessive air leaking into the system. In some embodiments, the blockage or leak can be determined by measuring the speed of the pump when the pump is working to maintain a constant negative pressure. The pump speed can also be measured indirectly by measuring the amount of voltage or signal sent to the pump.

[0103] Fig. 7A -C shows a view of a 3D fabric that can be used in various embodiments described herein, such as Figure 4A-6 5502 of the suction adapter shown in FIG. Although other porous materials (such as foam) can be used in the embodiments described herein, for example in Figure 5B -C, but in some cases, the use of 3D fabrics may be advantageous. It has been found that certain 3D fabrics perform well in delivering negative pressure to the fluid suction adapter and delivering wound exudate from the fluid suction adapter even when compressed (for example, when the weight of the patient is placed directly on the suction adapter, or when negative pressure is applied and / or when the fluid suction adapter is kinked or folded). Some 3D fabrics that have been found to have acceptable performance include knitted polyester 3D fabrics, Baltex7970.RTM., Gehring879.RTM., or Coolmax.RTM. Of course, other fiber and fabric types can be used in part or in whole to make 3D fabrics, and include but are not limited to polyamides such as nylon, viscose, cotton, and other synthetic microfibers. 3D fabrics can also be at least partially constructed of fibers such as Nomex.RTM. and Kevlar.RTM. Other types of fabrics and materials disclosed herein can also be used.

[0104] In one embodiment, Fig. 7A -C, the 3D fabric may include a bottom side 5603, a top side 5605 and an open middle area 5607. Fig. 7AThe bottom (wound-facing) side 5603 of a 3D fabric is shown, which may be woven so as to produce oblong or oval openings 5611 extending longitudinally across the fabric. In one embodiment, the oblong or oval openings 5611 represent or provide an open area between 10% and 45% (or about 10% to about 45%) of the surface area of ​​the underlying layer, more preferably 10% to 30% (or about 10% to about 30%). Here, the fibers are knitted (e.g., by warp knitting) so as to also include these larger openings or pores, which allow for bulk transport of wound fluids in addition to wound fluids transported along the fibers by capillary action of the fibers. An orifice (e.g., 3D fabric) may optionally be formed in the distal end of the 3D fabric. Figure 5B and 6 ) can also assist in the extensive drainage of wound debris and fluid.

[0105] Figure 7B A top side 5605 of a 3D fabric that can be used as described herein is shown. In one embodiment, this top side 5605 does not have the larger oval aperture 5611 of the bottom side 5603, but can have openings 5613 defined by fibers that extend across the width of the fabric longitudinally and generally laterally or at an angle. As shown, these openings are generally diamond-shaped. In one embodiment, these openings 5613 can represent or provide an open area that is larger than the bottom layer, for example, between 30% and 50% (or about 30% and about 50%). Of course, it should be understood that the fabrics shown here are non-limiting examples, and different fabric configurations and orientations are possible, for example, where the top side 5605 is placed downwardly so as to face the wound, and the bottom side 5603 faces upward.

[0106] Figure 7C A cross section of a 3D fabric is shown (the bulbous protrusions on the vertical fibers in the fabric are an artifact of the cutting process). The vertically extending fibers 5609 can be woven so as to extend through the middle open area 5607 while also being connected to the bottom layer 5603 and the top layer 5605. Preferably, the fibers 5609 present in the middle layer 5607 of the opening will have sufficient rigidity to help prevent compression of the fabric. As shown, and without wishing to be bound by theory, it has been found that a well-performing 3D fabric will generally include a larger open area 5607 in the middle portion, which can allow exudate and other fluids to be effectively transported away from the wound site when negative pressure is applied, while the more densely woven outer layers 5603, 5605 can help provide additional tensile strength and capillary wicking. For example, the middle layer may include an open volume greater than 50% (or greater than about 50%). Obviously, the resulting fabric cannot be too thick or composed of too hard fibers, because the resulting suction adapter and system may remain flexible enough to be comfortably used for patients.

[0107] It is generally advantageous to customize the performance characteristics of 3D fabrics in use to consider the various requirements of suction adapters. Specifically, for example, when in compression, the flow rate of exudate through the fabric can be simplified by considering the porosity of the fabric. In such cases, and again without wishing to be bound by theory, the porosity of the fabric and therefore the space available for fluid travel can be determined in part by the knitting pattern of the fibers used to make the 3D fabric, the thickness of the fibers used therein, and their respective rigidity and hardness (especially when under compression). The fibers can also be modified by the number of fibers or filaments used in the surface properties (the fibers can be flat or textured) and the resulting fabric. The compression resistance may be affected by the selection of the fibers or monofilaments used in the vertical axis of the fabric, and generally harder materials will improve the compression resistance on the axis. Other material properties such as hydrophobicity may work. In some cases, it may be beneficial to treat the fabric to be hydrophilic with a hydrophilic polymer so as to improve the wicking of the fluid. It has been found that the preferred embodiment of the 3D fabric used with certain suction adapters works well when the Baltex.RTM. fabric is treated in this way. Other possible treatments may include lipophilic coatings to prevent protein adhesion and accumulation during use, which could lead to clogging and loss of pressure at the wound site.

[0108] The flow rate through the 3D fabric when negative pressure is applied can be estimated by treating each opening as a separate orifice plate constrained by the Bernoulli principle under laminar flow conditions. To simplify the calculation, the opening area can be used for a given area of ​​the 3D fabric. Therefore, the 3D fabric can be optimized to achieve a good balance between factors such as the required compression resistance and the resulting flow rate under the application of negative pressure. In the case of the stiffness and flow rate of the 3D fabric customized according to the application in the embodiments described herein, further optimization will also occur. The optimization of the properties and dimensions of the 3D fabric will also preferably consider the balance between the required flow rate and stiffness and the conformability of the fabric, because a too stiff fabric may not be able to bend properly and may also be uncomfortable for the patient. The 3D fabric should preferably be designed to bend when pressed against the tissue, thereby preventing tissue compression (e.g., for bone protrusions in patients) and possible subsequent discomfort and injury, such as pressure sores. For example, the size of the fabric can be customized for the final use of the suction adapter, which is smaller in the case of distal limbs such as fingers and larger for the abdomen and burn wounds. Too stiff a fabric may also cause pressure sores and other such complications, even though it may function acceptably in larger sizes.

[0109] In practice, and as also described previously herein, the flow rate of an embodiment of a suction adapter using a 3D fabric is at least 0.08 L / min, preferably up to 10 L / min, during application of negative pressure, and should be able to handle at least 10 L / day of fluid exudate discharge. Some embodiments of the suction adapter may be configured to handle much larger wounds, including abdominal wounds, and in some cases, may exude at least 0.5 L / hour or 12 L / day. In more extreme cases, the pump used (e.g., RENASYS EZ) may be able to evacuate up to 16 L / min, thereby evacuating a large wound to a negative pressure level of 120 mmHg in less than a minute. The calculated pressure drop due to the 3D fabric should be minimal, and the negative pressure level measured at the wound site is preferably within 25 mmHg of the pressure level measured at the negative pressure source. Although the pressure drop increases with increasing applied negative pressure (thereby making the 25 mmHg target more difficult to achieve), embodiments of the wound treatment system are preferably able to maintain this target pressure to a negative pressure of at least 200 mmHg. The suction adapter and system are preferably capable of functioning within the pressure range required for negative pressure, which is estimated to be approximately 40 mmHg to 200 mmHg. A pressure range greater than 200 mmHg is possible, but may cause patient discomfort in some cases. The device can also function at a lower pressure range (such as 20 mmHg), but at such low pressure levels, the therapeutic effect produced by the negative pressure may be reduced, with the device acting more as a discharge device. Preferably, an embodiment of the negative pressure therapy system is capable of maintaining these target pressures at the wound site within 95% of the time when negative pressure is applied to the wound. In some embodiments, the fabric may include several layers of material stacked or laminated on each other, which may be used in some cases to prevent the channel 5516 from collapsing under the application of negative pressure. In other embodiments, the fabric used in the channel 5516 may be between 1.5 mm and 6 mm; more preferably, the fabric may be between 3 mm and 6 mm thick, and may include one or several independent layers of fabric. In other embodiments, the channel 5512 may be 1.2-3 mm thick, and preferably thicker than 1.5 mm. Preferably, the 3D fabric can withstand a load of at least 5.3 psi without compressing more than 10% of the original thickness of the fabric. In addition, the 3D fabric can also resist compression to less than half of its original thickness when subjected to a load of 15 psi.

[0110] In a preferred embodiment, the 3D fabric can be woven from 100% polyester using yarns of 150 and 225 denier to produce a fabric weighing approximately 23 to 25 ounces per square yard. In these cases, the fabric may be approximately 5.8-6.8 mm thick. The bottom portion of the fabric may also have Fig. 7AThe plurality of openings or apertures 5611 similar to those shown in FIG. 5 and 6 may be elongated, rectangular or oval and oriented with their long axes longitudinally along the fabric. The openings 5611 may be arranged in a plurality of rows extending longitudinally across the fabric, such as 2 to 5 rows, or more preferably 3 rows, such as Fig. 7A As shown in . Openings 5611 can be spaced equidistantly from each other in each row, and a staggered pattern from one row to another can be formed. In one embodiment, each row can have about 6-10 openings per 2 inches (or about 50mm), more preferably 8 openings. Along a given width or lateral dimension of the fabric, the lateral row formed by the openings can have about 6-10 openings per 21 / 8 inches (or about 54mm), more preferably 8 openings. In one embodiment, the openings can have a length between about 1 / 16" and about 1", and a width between about 1 / 32" and 1 / 2". In one example, the measured longitudinal length of the opening is about 1 / 8" (or about 3.2mm), and the horizontal width is 1 / 32" (or about 0.79mm). In one embodiment, the 3D fabric can have a total length between about 50mm and 100mm, more preferably about 60mm, a width between about 5mm and 15mm, more preferably about 9mm, and a thickness of about 6mm.

[0111] Embodiments of the systems described herein have been tested and found to perform satisfactorily. Such tests are performed by constructing a suction adapter from the embodiments described herein. The distal end of the suction adapter is then placed above an orifice made into a drape, which is placed above a simulated wound cavity provided with a simulated wound fluid source, which is controllable and can change the flow rate of the wound fluid. In some cases, the simulated wound cavity is also filled with foam or some other wound filling material. In some tests, the simulated wound fluid was a 5:1 water to glycerol mixture, while in others, filtered horse serum (available from Oxoid in the UK) was used. The proximal end of the suction adapter is then connected to a negative pressure source, in this case a pump. Flow rate tests and other measurements are then performed under various negative pressure ranges and simulated exudate flow rates and air leakage rates.

[0112] Fig. 8A An embodiment of a connector 5704 is shown that is similar to the previously described connector 5506 and can be used to securely connect a negative pressure source to a channel 5716 of a suction adapter, such as the suction adapter described herein. For example, the channel 5716 can be the upper channel 5512, or more preferably, Figure 5A-Figure 65516 in the lower channel 5516. In general, such connectors 5704 can be used to provide a more secure connection from a negative pressure source to a negative pressure therapy system. The use of these connectors 5704 is optional and may not be necessary in all embodiments described herein. In use, the tube 5740 connected to the connector 5704 may be pulled out, or other external forces may somehow cause the connector 5704 to be detached from the channel 5716 to which it is attached. In such cases, negative pressure can be reduced or stopped from being applied to the wound. As described above, other means of fixing the connector 5704 to the rest of the system may include bonding or attaching other layers of the treatment system (if present) to the connector 5704. The connector 5704 may be designed to form a secure connection with the fabric or material used in the channel; when a 3D fabric or 3D knitted material is used, some embodiments of the connector 5704 are configured to engage or attach a portion of the material or material fiber to produce a more secure connection. Preferably, the embodiment of the connector 5704 is able to withstand a tensile force of up to 20 kg before the connector is disconnected and / or fails, preferably causing the connector to be detached from the channel to which it is connected. It should be understood that other embodiments may be configured to withstand lower tensile forces and may be customized to release to prevent injury to the patient (e.g., constriction of the suction adapter and / or exhaust tube around a limb).

[0113] Figure 8B An embodiment of a connector 5704a is shown that includes two or more protrusions 5752 extending longitudinally distally from a preferably cylindrical body of the connector 5704a. The body also includes a central channel 5755 extending longitudinally through the body of the connector 5704a. The protrusion 5752 may further include one or more barbs 5754 attached thereto. Preferably, these barbs 5754 are angled proximally so as to act as anchors when pushed or inserted into the channel 5716. When the channel 5716 is a 3D fabric or knitted material, the barbs 5754 are configured to engage the fibers therein, thereby creating a more secure connection. At the proximal end of the connector 5704a, a lip 5756 may also be provided for connection to the tube 5740, and the lip may be provided in the form of a truncated cone. The tube 5740 may be connected to the connector 5704a (and other connectors described herein), for example, by a press fit, but other connection arrangements are possible. The tube 5740 may be connected to the connector 5704a (and other connectors described herein), for example, by a press fit, but other connection arrangements are possible. The tube 5740 may be connected to the connector 5704a (and other connectors described herein). Figure 65507 in, or it may be any other tube for providing fluid communication with a negative pressure source. It will also be appreciated that the features of these connectors, particularly at the distal end, may be incorporated into the ends of tubes for delivering negative pressure so that these tubes may be directly connected to a suction adapter system. Examples of such applications in which additional disclosures related to the foregoing description of connectors may be found include U.S. Patent No. 9,050,398, entitled “APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY,” issued June 9, 2015, the entire contents of which are incorporated herein by reference.

[0114] Flexible suction adapter with separate leak port

[0115] Fig.9A -C shows an embodiment of a flexible suction adapter 900, which is similar to Figures 4A-8B An embodiment of a flexible suction adapter 5500 is shown in and described with respect to the figures. Fig.9A An exploded view of the suction adapter 900 is shown, and Fig. 9B A top view of the suction adapter 900 is shown. Fig. 9C A cross-sectional view of a suction adapter 900 is shown. The suction adapter 900 may include a bridging portion 902 having a proximal end 903 and a distal end 905, and an applicator 920 at the distal end 905 of the bridging portion 902 to form a flexible suction adapter 900. Preferably, the flexible suction adapter is constructed in a similar manner to the flexible suction adapter 5500, and the bridging portion 902 may be constructed of a similar double-layer arrangement as previously described. For example, in some embodiments, the bridging portion 902 may include an upper channel layer 912 positioned between an upper layer 910 and a middle layer 914, wherein a lower channel layer 916 is positioned between the middle layer 914 and the bottom layer 918.

[0116] In certain embodiments, for example, Fig.9A -C, a controlled leak 924 may be provided on the bridge portion 902, for example near its proximal end. This leak 924 may include an opening or channel extending through the upper layer 910, so that the leak 924 is in fluid communication with the upper channel 912. The leak 924 may include a filter 925.

[0117] The applicator 920 preferably includes an attachment point for the bridge portion 902 at the distal end 905, such as using a length of double-sided adhesive tape 928. It should be understood that different attachment methods are also contemplated, such as heat sealing, welding, or a suitable adhesive.

[0118] A connector 904 may be provided at the proximal end 903 of the bridging portion 902 for connection to at least one of the channels 912 and / or 916. The cap 936 may be provided with a suction adapter 900 (and in some cases may be attached to the connector 904 as shown). Fig.9A As shown, the channel connector 906 can be provided at the proximal end 903 of the bridge portion 902, and the channel connector 906 is preferably configured to be embedded in the lower channel layer 916 to create a secure fluid connection. In the case where one end of the channel connector 906 is embedded in the lower channel layer 916, the other end of the channel connector 906 can be connected to the connector tube 907 or communicate with it, but in some embodiments, the channel connector 906 can be directly connected to the connector 904, or directly connected to a tube connected to a negative pressure source.

[0119] Each component of suction adapter 900 may be similar to each corresponding component of suction adapter 5500 , and thus the description previously provided herein of each corresponding component of suction adapter 5500 also applies to each component of suction adapter 900 , except as described below.

[0120] In a similar manner to the suction adapter 5500, the upper fluid passage can be defined by and between the upper layer 910 and the middle layer 914. In some embodiments, as Fig. 9C As shown, the upper layer 910 and the lower layer 918 extend further at the distal end 905 than the middle layer 914, so that the upper fluid passage may also be partially defined between the upper layer 910 and the lower layer 918. The upper fluid passage may include an upper channel spacer layer 912. The lower fluid passage may include a lower channel spacer layer 916. In some embodiments where the upper layer 910 extends further than the middle layer 914 at the distal end 905, the upper channel spacer layer 912 may also extend further than the middle layer 914 and the lower channel spacer layer 916 at the distal end 912 to support the upper layer 910. Fig.9A -C. In some embodiments, the distal ends of layers 910, 914 and 918 and channel layers 912 and 916 are enlarged at their distal ends (placed above the wound site) and may form a "teardrop" or other enlarged shape. The distal ends of at least layers 912 and 916 may also be provided with at least one through-hole. This hole can not only be used to drain wound exudate and apply negative pressure to the wound, but can also be used during the manufacture of the device because these holes can be used to properly align these corresponding layers. In other embodiments, the upper fluid channel may further include an auxiliary spacer layer 970 placed below the distal end of the upper channel spacer layer 912 and distal to the distal end of the lower channel spacer layer 916, so that the auxiliary spacer layer 970 supports the distal end of the upper channel spacer layer 912. As shown Fig.9A and 9C , the auxiliary spacer layer 970 may include one or more apertures that may be aligned with one or more apertures at the distal end of the spacer layer 912 .

[0121] In some embodiments, Fig.9A and 9C As shown, the suction adapter 900 includes two orifices at the lower layer 918: a leakage channel orifice 952 and a suction orifice 954, both of which are formed at the lower layer 918, for example, at the enlarged distal end of the lower layer 918. In some embodiments, the leakage orifice 952 and / or the suction orifice 954 can be formed as a plurality of smaller orifices. As shown, the orifices 952 and 954 can be spaced apart, wherein the orifice 954 is located on the proximal side of the orifice 952. These orifices can all be located on the central longitudinal axis of the lower layer 918, or one or both orifices can not be located on the central longitudinal axis. The applicator 920 may have two openings 962 and 926, which are configured to align with the leakage channel orifice 952 and the suction orifice 954.

[0122] like Fig. 9C , the leakage channel orifice 952 can be fluidly connected to the upper fluid channel having the upper channel spacer layer 912, thereby forming a leakage flow extending from the leakage port 924 to the leakage channel orifice 952 distally. Fig. 9C As shown, this leakage flow extends through the auxiliary spacer layer 970. Moreover, the suction orifice 954 can be fluidly connected to the lower fluid channel having the lower channel spacer layer 916, thereby forming a suction flow extending distally from the connector 904 and / or the negative pressure source.

[0123] In some embodiments, the upper layer 910 can form a fluid tight seal with the middle layer 914 and / or the lower layer 918, and the middle layer 914 can form a fluid tight seal with the lower layer 918, so that the upper fluid channel extending distally from the leak port 924 to the leak channel orifice 952 can be fluidly separated from the lower fluid channel extending distally from the connector 904 to the suction orifice 954. Fig. 9C As shown, in some embodiments, the distal end of the middle layer 914 can extend between the auxiliary spacer layer 970 and the lower channel spacer layer 916 and seal with the lower layer 918, thereby separating the upper fluid channel and the lower fluid channel. The upper layer 910, the middle layer 914, and the lower layer 918 can be sealed to each other using any means previously described herein, such as by melting, welding, or with an adhesive.

[0124] The leakage orifice 952 and the suction orifice 954 can be sufficiently spaced apart from each other so that wound exudate drawn to the suction orifice 954 does not enter the leakage orifice 952. In some embodiments, the upper fluid channel may include a filter (not shown) near the leakage orifice 952 to prevent wound exudate from entering the upper fluid channel and blocking the upper fluid channel. The filter may be permeable to air to allow air from the leakage port to be provided to the wound dressing, but may be impermeable to liquids or bacteria. The filter disposed at the leakage orifice 952 may be similar to the filter 5525 previously described herein.

[0125] In some embodiments, the lower fluid passage may include a filter (not shown) near the suction orifice 954. The filter is configured to substantially prevent wound exudate from entering the lower fluid passage. Preferably, the filter may be impermeable to liquids but permeable to gases, and is provided to act as a liquid barrier and ensure that no liquid can escape from the wound dressing, so that a tank for collecting wound fluids may not be required between the suction adapter and the negative pressure source. The filter may be hydrophobic. The filter may be attached or sealed to the suction adapter and / or cover film above the wound dressing. For example, the filter may be molded into the suction adapter 900, or may be adhered to the lower layer 918 of the suction adapter 900 using an adhesive (such as, but not limited to, a UV-cured adhesive).

[0126] The auxiliary spacer 970 can be constructed of any flexible material suitable for conveying air from the controlled leak port. The auxiliary spacer 970 can be constructed of any material suitable for the upper channel spacer layer 912, 5512 and the lower channel spacer layer 916, 5516 as described above, for example, an open-cell foam such as polyethylene or polyurethane, or a fabric such as a knitted or woven spacer fabric (such as a knitted polyester 3D fabric, Baltex 7970.RTM. or Gehring 879.RTM.) or a non-woven material.

[0127] exist Fig.9A and 9C In the illustrated embodiment 900 of the present invention, the double-sided adhesive tape 928 is adhered around the suction orifices 926 and 954, thereby fixing the applicator 920 to the lower layer 918. However, in some embodiments, the size and shape of the double-sided adhesive tape 928 can be set to adhere around the leakage orifices 952 and 962 or both the orifices 962 / 952 and 926 / 954. In some embodiments, the suction adapter 900 may include an additional double-sided adhesive tape (not shown) similar to the adhesive tape 928 to adhere around the leakage orifices 952 and 962. In some embodiments, in addition or alternatively to the double-sided adhesive tape, the applicator can be attached to the lower layer 918 with glue and / or welding.

[0128] During operation, Fig.9A-C provides a leakage path extending into the wound dressing that is fluidly separated from a suction flow path extending from the wound dressing to the negative pressure source. Figure 5A-6 In contrast, the leakage path in the wound dressing is fluidly connected to the suction flow path above the wound dressing. Figure 5A-6 In an embodiment, if the orifice 5526 is blocked, for example, the suction adapter is not properly positioned above an opening formed in a wound cover placed above the wound, or if the orifice 5526 is blocked by wound exudate, the negative pressure source can continue to operate by drawing air from the leak port and draw air from the suction adapter. This can make it difficult to detect blockage of the suction adapter or misalignment of the suction adapter over the opening in the wound cover. By having a leak path that is fluidly separated from the suction flow path as described herein, if the suction orifice 926 is blocked, the negative pressure source can stop drawing air from the suction adapter because the leak will only flow through the wound. Therefore, this can detect blockage of the suction adapter. In addition, by having a separate controlled leak path, it will be easier to measure the flow or pressure through the suction flow path without being disturbed by the leak.

[0129] although Fig.9A -C shows an example of a flexible suction adapter 900 with a fluidly separated or isolated leakage channel (upper fluid channel) and a suction channel (lower fluid channel), but other arrangements of the flexible suction adapter 900 that separate the fluids of the isolated leakage channel and the suction channel are possible. For example, the leakage channel and the suction channel can be arranged side by side, rather than placing one channel on top of the other. In some embodiments, two physically separated hoses can be connected to the wound bed, where one tube will only serve as a means to allow transmission from a negative pressure source, and the other tube only serves as a leakage channel to allow air from a controlled leakage port to flow into the wound.

[0130] Fig.10 A diagram of a system 1000 for applying negative pressure, for example using a suction adapter 900 or any suction adapter with a separate leak path, is shown according to some embodiments. As shown, the system 1000 includes a negative pressure source 1022 fluidly connected to a wound dressing 1006 via a fluid flow path 1040 to supply negative pressure to one or more wound sites. The fluid flow path 1040 includes a suction adapter 1020 and a tube 1042 connected by a connector 1052. The suction adapter 1020 also includes a leak port 1012 configured to introduce air into the suction adapter 1020.

[0131] like Fig.10As shown, the suction adapter 1020 includes a calibrated leakage path 1026 and a suction path 1024. The suction path 1024 is fluidly connected to the fluid flow path 1040 through the connector 1052 so as to supply negative pressure to the wound site through the wound dressing 1006. The calibrated leakage path 1026 is fluidly connected to the air leakage port 1012 so as to supply air from the air leakage port through the wound dressing 1006 into the wound. Fig.10 As shown, the calibrated leak path 1026 and the suction path 1024 can be as previously described herein. Fig.9A -C as described above, only connected to each other through the wound fluid. In some embodiments, the leak port 1012 can be set at any suitable position in the fluid flow path. For example, the leak port 1012 can be incorporated into the connector 1052. In some embodiments, the leak port can be electronically or electromechanically adjusted by the controller of the system to close or expand the leak. For example, the controller can communicate with the leak port to open or close each leak port individually or as a unit. For example, the leak port can be a solenoid valve. The communication between the leak port and the controller can be wired or wireless.

[0132] In some embodiments, the suction adapter 1020 can maintain a constant leakage rate through the leak port 1012 while applying negative pressure through a negative pressure source. Some embodiments can support leaks of 1, 2, 3, 4, 5, 6, 7, 8, 9 mL / min or more (+ / - 0.5 mL / min or another suitable deviation). Some embodiments can support leaks of 10, 20, 30, 40, 50, 60, 70, 80, 90 mL / min or more (+ / - several mL / min or another suitable deviation). Some embodiments can support leaks of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 L / min or more (+ / - several centiliters / min or another suitable deviation). In some cases, the leak rate can be discussed in terms of a controlled leak path (CLP), where CLP is a suitable constant. For example, the leak port may have a leak rate of 0.25, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more. For example, assuming a leak rate of 0.1 L / min, 1 CLP may correspond to 0.1 L / min, 5 CLPs may correspond to 0.5 L / min, and so on. The negative pressure source must work harder with a higher intensity leak, which can drain the power supply faster. Therefore, in some embodiments, a relatively low leak rate is selected.

[0133] Multi-dressing negative pressure wound therapy

[0134] Figures 11A-11BA negative pressure wound therapy system 400 is shown according to some embodiments. Systems 400a, 400b (collectively 400) may include a pump assembly or negative pressure unit 434 capable of supplying negative pressure. In some embodiments, negative pressure unit 434 is coupled to Figure 2 The negative pressure unit 434 can be fluidly connected to one or more wound dressings 406a, 406b (collectively referred to as 406) to supply negative pressure to one or more wounds. In some embodiments, the fluid connection between the wound dressing 406 and the negative pressure unit 434 is referred to as a fluid flow path (e.g., a path through which fluid is drawn from the wound via negative pressure flow). For example, a first fluid flow path may include a component that provides a fluid connection from the negative pressure unit 434 to the first wound dressing 406a. As a non-limiting example, the first fluid flow path may include a path from the wound dressing 406a to the negative pressure unit 434 or a path from the first wound dressing 406a to an inlet of a branch attachment 444 that is fluidly connected to the negative pressure unit 434. As shown, the system 400 may include a plurality of suction adapters (such as those described with respect to Fig.9A -C Suction adapter 900 and / or regarding Fig.10 The suction adapter 1020 described herein is a plurality of wound dressings (and corresponding fluid flow paths) that are fluidically connected to the negative pressure unit 434. Therefore, the description of the suction adapters 900 and 1020 and their components herein can also be applied to the suction adapters and their components in systems 400a and 400b. For example, the suction adapters for systems 400a and 400b may include a controlled leakage channel that is fluidly separated from the suction channel. Each wound dressing and fluid flow path may include various features or elements that match or are similar to the features or elements of another wound dressing or fluid flow path within the system. For ease of reference, one or more corresponding features or elements may be collectively referenced using figure numbers without corresponding letters. For example, bridge 402a and bridge 402b may be collectively referred to as bridge 402. However, it should be noted that in some embodiments, the elements that have been mentioned together are not the same and may have different features or attributes.

[0135] refer to Fig.11A , system 400a may include a suction adapter, such as suction adapter 900 or 1020, including a bridge 402 having a proximal end 403 and a distal end 405, and an applicator 420 forming a flexible suction interface or adapter at the distal end 405 of the bridge 402. Negative pressure unit 434 may include a tank or other container for storing wound exudate and other fluids that can be removed from the wound. Negative pressure unit 434 may be about Figure 2The negative pressure unit 5534 described above may include a negative pressure unit 5534. Alternatively or additionally, the wound dressing 406 may collect wound exudate and other fluids, and the canister may not be present. In some embodiments, multiple canisters are provided, such as one canister per wound dressing. In some embodiments, the negative pressure unit 434 may be a Renasys Touch device manufactured by Smith & Nephew. In some embodiments, connectors other than the Renasys SoftPort or devices other than the Renasys Touch may be used.

[0136] Fig. 11B Shows Fig.11A An embodiment in which a flexible suction adapter has been placed over a wound. In some embodiments, the applicator 420 is placed over an orifice 435 formed in a drape 431, which is placed over a suitably prepared wound 430, which in some cases may be filled with a wound packing material, such as foam or gauze. Subsequently, with the negative pressure unit 434 connected to the connector 404 via tube 440 or an inlet manifold branch attachment or connector 444, the negative pressure unit 434 is activated, thereby supplying negative pressure to the wound via a fluid flow path. Negative pressure may be applied until a desired level of healing of the wound 430 is achieved. Although in Figures 11A-11B Two wounds and wound dressings are shown, in some embodiments, negative pressure unit 434 can provide treatment to more than two wounds. In some embodiments, negative pressure wound therapy can be provided to a single wound.

[0137] appendix

[0138] The negative pressure unit 434 can be fluidly connected to the wound dressing 406 via one or more tubes 440, 442, one or more bridges 402, or via an inlet manifold branch attachment 444. For example, the negative pressure unit 434 can be fluidly connected to multiple wound dressings 406 via tubes 440, inlet manifold branch attachments 444, tubes 442, and bridges 402. As another example, the manifold branch attachment 444 can be directly connected to the negative pressure unit 434 without using tubes 440. Figures 11A-11B As shown, the inlet manifold branch attachment 444 can be configured to connect the negative pressure unit 434 to multiple fluid flow paths via multiple dressing conduit attachment portions 445a, 445b. The inlet manifold branch attachment 444 can include any number of dressing conduit attachment portions 445 configured to be fluidly connected to the negative pressure attachment portion 446 via a connector. For example, the inlet manifold branch attachment can include two dressing conduit attachment portions 445a, 445b, three dressing conduit attachment portions, or more than three dressing conduit attachment portions.

[0139] The plurality of dressing conduit attachment portions 445 may include a first dressing conduit attachment portion 445a and a second dressing conduit attachment portion 445b. However, it will be appreciated that more or fewer dressing conduit attachment portions may be included in the inlet manifold branch attachment 444. Each of the dressing conduit attachment portions 445 includes a shaft extending away from the connector and including an inlet distal to the connector. The inlet is configured to fluidly connect at least a portion of the fluid flow path to the negative pressure unit 434.

[0140] The inlet manifold branch attachment 444 may also include one or more negative pressure attachment portions 446. Each of the negative pressure attachment portions 446 may include an axis extending away from the connector and an inlet at the distal end of the connector. The inlet may be configured to be fluidically connected to the negative pressure unit 434. For example, the inlet may include a male non-Luer connector or a female non-Luer connector to attach to a corresponding male connector or female connector of a catheter or pump. In some embodiments, the negative pressure attachment portion 446 is attached to the negative pressure unit 434 via a conduit 440 or other conduit. The negative pressure attachment portion 446 may also be directly attached to the housing of the negative pressure unit 434 (or may be integrated with it).

[0141] The inlet manifold branch attachment 444 or conduit may include one or more valves, clamps, covers, leaks or other flow regulator mechanisms that are incorporated, which may be configured to introduce fluid into the fluid flow path, or alternatively block or restrict the flow or passage of fluid through the fluid flow path. In some embodiments, the valves, leaks or other flow regulating mechanisms in the inlet manifold branch attachment 444 can be opened or closed electronically. For example, the controller of the negative pressure unit 434 can communicate with the valves, leaks, etc. to open or close each individually or as a unit. This communication can be wired or wireless.

[0142] The dressing catheter attachment portion 445 may include a shaft forming a top portion of a Y-shape (two wounds), a W-shape (three wounds), or other shapes of an inlet manifold branch attachment. The proximal end of the dressing catheter shaft and the distal end of the pump catheter shaft may meet at a joint. In some embodiments, the joint may include a hinge that allows the shaft to rotate about the joint. In some embodiments, the inlet manifold branch attachment may be a W-shaped connector (e.g., Figure 6 ). In embodiments such as these, the inlet manifold branch attachment may include three or more dressing conduit attachment portions and one negative pressure attachment portion.

[0143] The inlet manifold branch attachments may include rigid plastic or flexible plastic tubing and may also or alternatively be wrapped in a soft silicone sleeve to increase patient comfort and prevent the inlet manifold branch attachments 444 from becoming a pressure point.

[0144] In some embodiments, by attaching the negative pressure unit to multiple wound dressings 406 using an inlet manifold branch attachment, the negative pressure unit can simultaneously draw fluid from multiple wounds 430. The performance and wound healing capabilities (e.g., fluid management) of the system can equal or exceed the performance and wound healing capabilities of a standard single wound dressing with a single pump setup.

[0145] In some embodiments, an integrated inlet manifold (not shown) may be used in place of inlet manifold branch attachment 444. In examples such as these, the inlet manifold may be incorporated (e.g., directly attached) into the negative pressure unit 434 or pump housing such that one or more fluid flow paths may be fluidly connected to the pump via one or more inlets of the integrated inlet manifold. The integrated inlet manifold may include a flow splitting attachment (similar to the Y-shaped or W-shaped branch attachments described herein), or may include one or more separate integrated inlets that are fluidly connected to the pump.

[0146] Determine the operation status

[0147] In some embodiments, the system 400 may apply negative pressure to one or more wounds. The negative pressure level at one or more wounds (e.g., under one or more wound dressings) may be sufficiently close to the negative pressure level at the negative pressure source. For example, the acceptable pressure level maintained at the wound may be within ±1 mmHg, ±5 mmHg, ±10 mmHg, ±25 mmHg, etc. of the negative pressure set point. In some embodiments, this pressure may be maintained at this level for 95% (or another suitable percentage) of the time that the system 400 applies negative pressure to it. In some embodiments, the acceptable pressure level may include a pressure range between -40 and -120 mmHg. However, other pressure levels may be used as described herein.

[0148] As described in more detail herein, one or more leaks in one or more fluid flow paths, such as leaks 424, 5524, 924 or 1012, can be used to determine one or more operating states within the system. For example, the leak can be a controlled leak that allows a relatively constant flow of air, gas or other fluid to enter the fluid flow path. In some embodiments, as additional negative pressure is applied to the system, the flow rate entering the fluid flow path from the leak will not increase significantly. However, when a steady state has been reached (e.g., when a negative pressure set point has been reached), the leak present in the system can maintain a substantially constant baseline flow through the system. In turn, the presence of a leak may require the negative pressure source to work harder to maintain the desired negative pressure level at the wound. Therefore, the system can determine the presence of one or more operating states (such as blockage, leakage, tank filling, misalignment of the suction adapter, etc.) by monitoring the flow through the fluid flow path, and the flow can be measured directly or indirectly based on, for example, monitoring the activity of the negative pressure source.

[0149] In some embodiments, each fluid flow path may include a leak port (e.g. Figures 11A-11B ), and each leak in the corresponding fluid flow path may allow a different flow rate of air, gas or other fluid to enter the system. In other words, each leak in the system may have a different leakage rate. For example, the leakage rate of the leak may be based at least in part on the size or shape of the leak, whether the leak includes a filter, the size or porosity level of the filter, the occlusion level of the leak or filter, etc. Fluid entering a fluid flow path increases the flow rate of the fluid flow path.

[0150] Thus, each fluid flow path of the system 400 may have a different flow rate. The total flow rate (TFR) of the system 400 (e.g., the aggregate of the flow to each wound dressing) may be monitored, calculated, or determined, and then used to determine an operational state of the system 400. The operational state may include, for example, a "no flow" state (e.g., all flow paths are blocked), an obstruction state of one or more flow paths (e.g., an obstruction state exists in a first fluid flow path, an obstruction state exists in a second fluid flow path, etc.), a tank full state, normal operation (e.g., no obstruction exists in any fluid flow path), and the like.

[0151] In some embodiments, the system 400 can provide an indication, such as an alarm, to inform the patient or caregiver of the operating state of the system 400 based on a comparison of the determined total flow rate to one or more flow thresholds. In some embodiments, the flow thresholds corresponding to the operating state of the system 400 are predetermined. In some embodiments, the flow thresholds are based at least in part on dynamic measurements or calculations, such as flow rate or pressure, made by the system 400 during a particular mode of the system (e.g., a calibration mode).

[0152] Fig.12A diagram of a system for applying negative pressure according to some embodiments is shown. As shown, the system 500 includes a negative pressure source 522 connected to the wound dressing 506a, 506b fluid via a fluid flow path 540d, an inlet manifold branch attachment 544, and fluid flow paths 540a, 540b, so as to supply negative pressure to one or more wound sites through suction paths 528a and 528b connected to the fluid flow paths 540a and 540b, respectively. The suction path 528a can be connected to the flow channel 540a using a connector 530, and the suction path 528b can be connected to the flow channel 540b using a connector 530. Each of the first fluid flow path 540a and the second fluid flow path 540b includes a leak port 512, 514, which is configured to introduce fluid into the controlled leak paths 526a and 526b, respectively. The controlled leak pathways 526a and 526b may be fluidly separated from the suction channels 528a and 528b such that the controlled leak pathways and the suction pathways are fluidly connected only through the wound bed.

[0153] In some embodiments, the leak port can be electronically or electromechanically adjusted by the controller of the system to close or expand the leak. For example, the controller can communicate with the leak port to open or close each leak port individually or as a unit. For example, the leak port can be a solenoid valve. The communication between the leak port and the controller can be wired or wireless.

[0154] In some embodiments, the system 500 or 1000 can maintain a constant leakage rate through the leak port while applying negative pressure through a negative pressure source. Some embodiments can support leaks of 1, 2, 3, 4, 5, 6, 7, 8, 9 mL / min or more (+ / - 0.5 mL / min or another suitable deviation). Some embodiments can support leaks of 10, 20, 30, 40, 50, 60, 70, 80, 90 mL / min or more (+ / - several mL / min or another suitable deviation). Some embodiments can support leaks of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 L / min or more (+ / - several centiliters / min or another suitable deviation). In some cases, the leak rate can be discussed in terms of a controlled leak path (CLP), where CLP is a suitable constant. For example, the leak port may have a leak rate of 0.25, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more. For example, assuming a leak rate of 0.1 L / min, 1 CLP may correspond to 0.1 L / min, 5 CLPs may correspond to 0.5 L / min, and so on. The negative pressure source must work harder with a higher intensity leak, which can drain the power supply faster. Therefore, in some embodiments, a relatively low leak rate is selected.

[0155] In some embodiments, the first leak port 512 has a different leak rate than the second leak port 514. For example, the first leak port may have a leak rate of 1 CLP, and the second leak port may have a leak rate of 2 CLP. Alternatively, the first leak port may have a leak rate of 0.5 CLP, and the second leak port may have a leak rate of 1 CLP. However, it should be noted that the leak rate of the system can be any suitable flow rate. Due to the different leak rates, the first fluid flow path 520a and the second fluid flow path 520b may have different flow rates. Alternatively, the first leak port 512 and the second leak port 514 may be equal or approximately equal (e.g., + / - 0.1 L / min or another suitable deviation). For example, the first leak port 512 and the second leak port 514 may each have a leak rate of 1 CLP. However, it should be noted that the leak rate of the system can be any suitable flow rate. Due to the equal leak rates, the first fluid flow path 520a and the second fluid flow path 520b may have similar flow rates. In some embodiments, the total flow rate (TFR) of the system is the aggregate of the flows from one or more wound dressings of the system. Thus, in some cases, the TFR may be equal to the flow rate of fluid flow path 520d.

[0156] Flow rate monitoring

[0157] The system 500 or 1000 can monitor or determine the TFR in the system based on, for example, monitoring the activity of the negative pressure source 522 or 1022. In some embodiments, the flow rate monitoring can be performed by a pump control processor (e.g., Figure 3 The pump control processor 370) alone or in combination with a processor (such as Figure 3 Monitoring flow rate may also be used to ensure that therapy is properly delivered to one or more wounds, detect blockages, tank full conditions, no flow conditions, or leaks in one or more fluid flow paths, high pressure, ensure that flow rates are not unsafe (e.g., dangerously high), etc.

[0158] In some embodiments, the system performs flow monitoring directly by using, for example, one or more flow meters positioned in the fluid flow path. In some embodiments, the system performs flow rate monitoring indirectly by measuring or monitoring the activity of the negative pressure source, such as by monitoring the activity of the actuator. For example, the system may monitor the activity of the vacuum pump motor, including monitoring the speed of the vacuum pump motor using a tachometer, monitoring the current or voltage supplied to the pump (e.g., the current or voltage of a PWM signal), etc. The system may continuously monitor one or more of these characteristics to determine the activity of the negative pressure source.

[0159] In some embodiments, a tachometer (e.g., a Hall Effect sensor) can be used to measure the activity level of the pump motor. The tachometer can be read periodically, such as every 100 msec or another suitable time period, and the periodic readings taken over a duration (e.g., 32 seconds or another suitable duration) can be combined (e.g., averaged). The combined tachometer readings can be used to determine the flow rate, which in turn can be used for leak detection, blockage detection, limiting maximum flow rate, etc. The combined tachometer readings (e.g., in units of times or pulses) can be converted to a flow rate (e.g., in units of mL / minute) using one or more conversion equations or tables, so that the TFR of the system (e.g., the aggregate of the flows in each fluid flow path associated with the wound dressing) is determined. In some embodiments, the TFR is determined according to the following equation:

[0160] TFR=C1*F*P+C2

[0161] Where TFR is the total flow rate, F is the frequency of the pump tachometer signal, P is the pressure generated by the pump (e.g., the negative pressure set point), and C1 and C2 are suitable constants (determined for a given negative pressure source). The determined flow rate can be compared to various flow rate thresholds (e.g., one or more occlusion thresholds) to determine the presence of a particular condition (e.g., an occlusion, a leak, a full tank, etc.).

[0162] In some embodiments, the total flow rate of the system can be determined. TFR may correspond to the sum of the leakage rates seen by the negative pressure source. For example, one or more conversion equations or conversion tables, etc., may be used, such as to determine the expected TFR in a calibration mode. If there is no leak, etc., the expected TFR may correspond to the system TFR in steady-state operation (e.g., when the negative pressure set point has been reached). The system may then monitor the TFR and compare it to one or more leak or flow rate thresholds to determine the presence of a particular condition, such as blockage, no flow, normal operation, tank fullness, etc. In some embodiments, the expected TFR may be determined in a non-steady state. In some cases, more than one expected TFR may be utilized.

[0163] In some embodiments, an occlusion condition is detected when the determined flow rate fails to meet one or more flow thresholds. For example, if an occlusion condition exists for a period of time, such as 30 seconds or another suitable period of time, an occlusion alarm can be enabled. This approach can implement hysteresis so that transient events do not cause the system to erroneously report the existence of one or more operating conditions. In embodiments where the system includes more than one wound dressing, a different occlusion alarm can be enabled for each wound dressing. When the determined flow rate exceeds one or more flow thresholds, the occlusion alarm can be disabled. In some embodiments, the system can distinguish between an occlusion in one or more fluid flow paths and a tank full state.

[0164] In some embodiments, blockage and presence of fluid in one or more fluid flow paths are detected by processing data from one or more pressure sensors (not shown), which may be positioned at any suitable location in the flow path. In some embodiments, the pressure sensor is positioned at or near the inlet of the negative pressure source. This detection may be enhanced by changing one or more settings of the pump, such as increasing the pressure level delivered by the pump, reducing the pressure level, stopping the pump, changing the pump speed, changing the rhythm of the pump, etc.

[0165] In some embodiments, the flow rate can be estimated as the volume of air, gas, or other fluid moved in the fluid flow path per unit time normalized to standard temperature and standard pressure (e.g., 1 atm). The flow rate can be calculated periodically, such as every 250 milliseconds or any other suitable time value, according to the following formula:

[0166] TFR = slope * tachometer + intercept

[0167] The tachometer is a short tachometer average (e.g., an average of recent tachometer readings (e.g., over 2.5 seconds or another suitable time period) which may be measured in Hz), and the slope and intercept are constants based on the negative pressure set point. For a given negative pressure source, values ​​for the slope and intercept may be determined for possible pressure set points (e.g., -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). The flow rate as a function of pump speed may not be a best fit as a single line because pumps may be designed to be more efficient at lower flow rates. Therefore, slope and intercept values ​​may be pre-calculated for various set points and various pumps. As described herein, the determined flow rate may be compared to various flow thresholds to determine the presence of a particular operating state (eg, an obstructed state, a no flow state, a tank full state, an abnormal state, a normal state, etc.).

[0168] In addition, the system can use one or more sensors to determine and monitor the pressure in the fluid flow path. For example, the fluid flow path may include a pressure sensor at or near the wound dressing 406, at or near the inlet manifold branch attachment 444, or anywhere else on the fluid flow path. In some embodiments, the pump assembly includes a pressure sensor in or near the inlet (or tank connection) of the pump assembly. The pressure sensor can measure the pressure in the tank (or in or near the dressing in a tankless system). The pump assembly can continuously measure the pressure in the tank, such as every millisecond or any other suitable duration. A suitable number of the most recent pressure sensor readings can be averaged to mitigate the effects of one or more erroneous readings.

[0169] Based on the determined total flow rate, the pump assembly can monitor and detect various operating conditions as described herein. One or more of these conditions can be detected by, for example, Fig.13 and 14 , or 800 as shown in the flowchart 700 or 800. Blockage in one or more fluid flow paths can be determined by comparing the total flow rate with one or more flow thresholds. The comparison can be implemented with a hysteresis, such as being performed continuously or substantially continuously within or during a period of time (such as 2 minutes or any other suitable duration). One or more flow thresholds can be selected or determined based on a specific pressure set point, because the expected TFR can also depend on the set point. That is, in order to detect blockage, the pump assembly can utilize multiple flow thresholds corresponding to a specific pressure set point. Alternatively or additionally, the flow threshold can be selected or determined based on the leakage rate of one or more leak ports. As explained herein, the flow rate can be indirectly determined by detecting and monitoring the pump speed.

[0170] If one or more flow thresholds are met or not met (e.g., within a period of time), the system determines that there is an obstruction in at least one of the fluid flow paths and provides an indication, which may include activating an alarm (e.g., visual, audio, or tactile), pausing the operation of the negative pressure, etc. For example, to determine the presence of an obstruction, the pump assembly may determine whether the total flow rate meets, exceeds, or drops below the flow threshold during a 2-minute period or during any other suitable period of time. Since the total flow rate can be updated at periodic time intervals due to the regular sampling of the tachometer, the pump assembly can compare the total flow rate when it updates to the flow threshold within a 2-minute period of time. As long as each total flow rate determined during the 2-minute interval meets, exceeds, or drops below the flow threshold, an obstruction can be detected. Alternatively or additionally, an obstruction can be detected if a majority of the calculated total flow rates (e.g., 9 out of 10 or any other suitable number) meet, exceed, or drop below the flow threshold. The detected obstruction can be cleared when the total flow rate drops below (or exceeds) one or more flow thresholds within a period of time (e.g., 5 seconds or any other suitable duration).

[0171] The threshold value may be any suitable flow threshold value, such as a value selected or determined based on a negative pressure set point and an expected flow rate in the fluid flow path, which may be determined as described herein.

[0172] In some embodiments, one or more flow sensors or flow meters can be used to directly measure fluid flow. In some embodiments, the pump assembly can utilize one or more of the techniques described herein in parallel to control the pump and detect various conditions. The pump assembly can be configured to appropriately arbitrate between parameters determined using different techniques. For example, the pump assembly can arbitrate between determining the flow rate indirectly (such as based on the pump speed measured by a tachometer) and determining the flow rate directly (such as by using a flow meter). In certain embodiments, the pump assembly can determine the flow rate indirectly and directly determine the flow rate when necessary, such as when the indirectly determined flow rate is considered inaccurate or unreliable.

[0173] In some embodiments, selecting or activating a Y-connection or W-connection feature for treating multiple wounds may change or modify the detection of one or more operating conditions, such as an obstruction, a leak, a tank full state, etc. Activating the Y-connection or W-connection feature may adjust one or more of the various thresholds described herein. In some embodiments, the system automatically detects the presence of a Y- or W-connector. For example, if a single wound dressing having a leak rate of 1 CLP is connected, the system may automatically detect the presence of a Y-connector by detecting a leak higher than the expected 1 CLP leak. For example, the system may prompt the user to confirm that another flow path, such as one having a leak rate of 2 CLPs, exists. Once the user confirms, the system will know to detect an obstruction and may determine a flow threshold based at least in part on the determination of the leak rate. Similar determinations may be used for a W-connector having three flow paths. For example, continuing the aforementioned example, if the system detects a leak higher than the expected 3 CLP leak, the system may detect the presence of a W-connector and may prompt the user to confirm that another flow path, such as one having a leak rate of 4 CLPs, exists. In some embodiments, a similar approach may be used when more than 3 wounds are being treated.

[0174] Fig.13 A flow chart is shown of a process 700 for determining and indicating one or more operating states, according to some embodiments. In some embodiments, the process 700 is implemented by the reduced pressure wound treatment system 500, such as by one or more controllers of the system.

[0175] At block 702, the process 700 determines one or more operating parameters. For example, the process 700 may determine the number of wound dressings attached, whether the fluid flow path corresponding to the attached wound dressing includes a leak, the leak rate of one or more leaks, the expected total flow rate (TFR) of the system, the expected flow rate of each fluid flow path, one or more flow thresholds, the activity level of the negative pressure source, etc. In some embodiments, the process 600 may perform one or more of such determinations in a calibration mode. Alternatively, some or all of these determinations may be automatically detected or received by the process as each wound dressing is attached. In some embodiments, a user may input some or all of the operating parameters, or the process may perform internal calculations, or may utilize conversion equations or conversion tables.

[0176] As described herein, in some embodiments, the process 700 can detect the presence of one or more attached wound dressings by detecting a higher than expected leak rate. For example, the process can automatically detect the presence of a Y-connector by detecting a leak higher than an expected leak rate and prompt the user to confirm that another flow path exists. Once the user confirms, the process will determine how to detect an obstruction. In other embodiments, the process can detect when a wound dressing is attached and will know the size of the leak based on the attached wound dressing.

[0177] Process 700 can also determine an expected flow rate for each of the fluid flow paths corresponding to each of the attached wound dressings. As described herein, each of the fluid flow paths can include one or more leak ports that can be configured to introduce fluid into the fluid flow path where the leak ports are located. Additionally, each of the leak ports can have a different leakage rate (e.g., the rate at which fluid is introduced into the fluid flow path). Thus, each of the fluid flow paths can have a different expected flow rate.

[0178] The process 700 may determine a plurality of flow thresholds based at least in part on the number of wound dressings or the leakage rate of one or more leaks. For example, the process may have two wound dressings, each with a different flow rate. The process may determine that a first flow threshold corresponds to a flow rate equal to the aggregate of an expected flow rate for the first fluid flow path and an expected flow rate for the second fluid flow path. The second flow threshold corresponds to the expected flow rate for the second fluid flow path. The third flow threshold corresponds to the expected flow rate for the first fluid flow path. Thus, if the monitored TFR meets the first flow threshold, the system operates normally. If the monitored TFR meets the second flow threshold, but does not meet the third flow threshold, the process may determine that the first fluid flow path is blocked. The process may make this determination because the process only detects flow in the second fluid flow path when the flow rate is equal to the expected flow rate for the second fluid flow path. Thus, the process does not detect any flow from the first fluid flow path, and therefore the process may determine that the first fluid flow path is blocked. In some embodiments, one or more of the thresholds may be higher or lower than the expected flow rate, for example to allow for variations during operation.

[0179] In some embodiments, the flow threshold may correspond to a leak rate of the system. For example, the system may have two wound dressings. Each wound dressing may have an associated fluid flow path. The first fluid flow path associated with the first wound dressing includes a leak port of 1 CLP. The second fluid flow path associated with the second wound dressing includes a leak port of 2 CLP. The process 700 may determine that the first flow threshold corresponds to a leak rate of 3 CLPs, the second flow threshold corresponds to a leak rate of 2 CLPs, and the third flow threshold corresponds to 1 CLP. Therefore, if the process detects a TFR of 1 CLP (e.g., the third threshold is met but the second threshold or the third threshold is not met), the process may determine that the second fluid flow path is blocked. The process may make this determination because the system only detects flow in the first fluid flow path when the TFR is equal to 1 CLP. Thus, the process does not detect flow from the second fluid flow path, and therefore the process may determine that the second fluid flow path is blocked. Similarly, if the process detects a TFR of 2 CLPs (e.g., the TFR meets the second threshold and does not meet the third threshold), the process can determine that the first fluid flow path is blocked. Likewise, if the process detects a TFR of 3 CLPs (e.g., the TFR meets the third threshold), the process can determine that neither the first fluid flow path or the second fluid flow path is blocked and the system is operating normally. Additionally, if the process detects no flow, the process can determine that the system is blocked due to, for example, all fluid flow paths being blocked or the tank being full. This is summarized in the following table:

[0180] Flow rate Sure 3 CLPs Normal Operation 2 CLPs The first fluid flow path is blocked 1 CLP The second fluid flow path is blocked 0 CLP The system is blocked

[0181] Table 1: CLP 1 and 2

[0182] In some embodiments, one or more of the thresholds may be higher or lower to account for inaccuracies. For example, although the first leak is equal to 1 CLP, the first flow threshold provides a small buffer (e.g., 0.03, 0.05, 0.1, 0.15, 0.2, or 0.25 CLP) such that the threshold is slightly below or slightly above 1 CLP. Similar buffers may be used for other flow thresholds. For example, the first threshold and the second threshold may be 0.5 and 1 CLP, respectively, and the process may make the following determinations:

[0183] Flow rate Sure 1.5 CLP Normal Operation 1 CLP The first fluid flow path is blocked 0.5 CLP The second fluid flow path is blocked 0 CLP The system is blocked

[0184] Table 2: CLP of 0.5 and 1

[0185] At box 704, process 700 uses one or more flow rate monitoring techniques described herein to monitor total flow rate (TFR). If one or more such techniques are performed in parallel, the process can be appropriately arbitrated between the flow rates determined using a variety of flow rate monitoring techniques. In certain embodiments, the process can perform one of the techniques, such as flow rate determination based on pump speed, and utilize one or more other techniques as needed. In various embodiments, in the case where the determination of flow rate is considered inaccurate or unreliable, the process can utilize one or more other techniques. In some embodiments, the total flow rate corresponds to the aggregate of the flow of each flow path in the process. For example, the total flow rate may correspond to the aggregate of the flow of the first fluid flow path and the flow of the second fluid flow path.

[0186] In some embodiments, the monitored TFR can be compared to the expected TFR to determine whether the system is operating normally. Thus, by comparing the monitored TFR to the expected TFR (e.g., by subtracting the expected TFR from the monitored TFR), process 700 can determine the deviation of the current flow rate from the expected flow rate. This deviation may be due to the presence of one or more operating conditions.

[0187] At block 706, process 700 determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a first flow threshold value, which may correspond to an expected TFR. If the first flow threshold value is met, then at block 708, the system may indicate that the system is operating normally. The indication in block 708 or any other block of process 700 may be performed using any of the approaches described herein.

[0188] If the monitored TFR does not meet the first threshold, the process 700 transitions to block 710, where the process determines whether the monitored TFR meets a second flow threshold. If the second flow threshold is met (e.g., the TFR is substantially equal to or above the second flow threshold), then at block 712, the process 700 may indicate that an obstruction condition exists in the first fluid flow path. The process may make this determination because, based on determining that the TFR meets the second threshold (and does not meet the first flow threshold), the process may determine that it is only detecting flow from the second fluid flow path.

[0189] If the monitored TFR does not meet the second threshold, the process 700 transitions to block 714, where it determines whether the monitored TFR meets a third flow threshold. If the third flow threshold is met (e.g., the TFR is substantially equal to or above the third threshold), then at block 716, the process may indicate that an obstruction condition exists in the second fluid flow path. The process may make this determination because, based on determining that the TFR meets the third threshold (and does not meet the first and second thresholds), the process may determine that it is only detecting flow from the first fluid flow path.

[0190] If the monitored TFR does not meet the third threshold, process 700 transitions to block 718 where it is determined and indicated that the system is blocked.

[0191] Although the examples provided in conjunction with process 700 generally relate to a system having a first wound dressing and a second wound dressing, it should be noted that similar techniques may be performed for a system having any number of wound dressings.

[0192] Furthermore, it should be understood that fewer, more, or different blocks may be used as part of process 700. For example, if, for example, one or more leak rates are equal or approximately equal (e.g., + / - 0.1 L / min or another suitable deviation), process 700 may include fewer blocks. As described above, a system may have two wound dressings, and each wound dressing may have an associated fluid flow path. For example, a first fluid flow path associated with a first wound dressing may include a leak of 1 CLP, and a second fluid flow path associated with a second wound dressing may also include a leak of 1 CLP. Thus, process 700 may utilize two flow thresholds: a first flow threshold corresponding to a leak rate of 2 CLP, and a second flow threshold corresponding to a leak rate of 1 CLP. If process 700 detects a TFR of 1 CLP (e.g., the first threshold is met but the second threshold is not met), the process may determine that the first fluid flow path or the second fluid flow path is blocked. Process 700 may make this determination because the process only detects flow from one of the fluid flow paths when the TFR is equal to 1 CLP. In some cases, the process may determine or indicate which fluid flow path is blocked, while in other cases, the process may determine or indicate that a blockage has occurred in one of the fluid flow paths. If the process 700 detects a TFR for both CLPs (e.g., the TFR meets a second threshold), the process may determine that neither the first fluid flow path nor the second fluid flow path is blocked and the system is operating normally. Additionally, if the process detects no flow, the process may determine that the system is blocked due to, for example, all fluid flow paths being blocked or the tank being full. This is summarized in the following table:

[0193] Flow rate Sure 2 CLPs Normal Operation 1 CLP A blockage occurs somewhere in the fluid flow path 0 CLP The system is blocked

[0194] Table 3: CLP is 1 and 1

[0195] Fig.14 A flow chart is shown of a process 800 for determining and indicating one or more operating states, according to some embodiments. In some embodiments, the process 800 is implemented by the reduced pressure wound treatment system 600, such as by one or more controllers of the system.

[0196] At block 802, process 800 determines one or more operating parameters, similar to reference Fig.13702 of . For example, the process may determine the number of wound dressings attached, whether the fluid flow path corresponding to the attached wound dressing includes a leak, the leak rate of one or more leaks, the total leak rate, the expected total flow rate (TFR) of the system, the expected flow rate of each of the fluid flow paths, one or more flow thresholds, the activity level of the pump, etc. In some embodiments, the process may perform some or all of these determinations in a calibration mode. Alternatively, some or all of these operating parameters may be automatically detected or received by the process as each wound dressing is attached. In some embodiments, a user may input some or all of the operating parameters, or the process may perform internal calculations, or may utilize conversion equations or conversion tables.

[0197] As described herein, process 800 can detect the presence of one or more attached wound dressings by detecting a higher than expected leak rate. For example, the process can automatically detect the presence of a W-shaped connector by detecting a leak higher than an expected leak rate and prompt the user to confirm that another flow path exists. Once the user confirms, the process will know how to detect a blockage. In other embodiments, the process can detect when a wound dressing is attached and will know the size of the leak based on the attached wound dressing.

[0198] Process 800 may determine a plurality of flow thresholds. In this example, the process may determine at least seven flow thresholds. However, it should be noted that more or fewer flow thresholds may be determined. Fig.13 As depicted in block 702 of FIG. 1 , the flow threshold may correspond to a TFR of the system in the presence of one or more operating conditions.

[0199] In some embodiments, the first flow threshold corresponds to a flow rate equal to the aggregate of the expected flow rate of the first fluid flow path (expected first flow rate), the expected flow rate of the second fluid flow path (expected second flow rate), and the expected flow rate of the third fluid flow path (expected third flow rate). The second flow threshold corresponds to a flow rate equal to the aggregate of the expected second flow rate and the expected third flow rate. The third flow threshold corresponds to a flow rate equal to the aggregate of the expected first flow rate and the expected third flow rate. The fourth flow threshold corresponds to a flow rate equal to the aggregate of the expected first flow rate and the expected second flow rate. The fifth flow threshold corresponds to a flow rate equal to the expected third flow rate. The sixth flow threshold corresponds to a flow rate equal to the expected second flow rate. The seventh flow threshold corresponds to a flow rate equal to the expected first flow rate.

[0200] For example, a first fluid flow path may have a leakage rate of 1 CLP, a second fluid flow path may have a leakage rate of 3 CLP, and a third fluid flow path may have a leakage rate of 5 CLP. A first flow threshold corresponds to a leakage rate equal to 9 CLP (e.g., the aggregate of all leakage rates). A second flow threshold corresponds to a leakage rate equal to 8 CLP. A third flow threshold corresponds to a leakage rate equal to 6 CLP. A fourth flow threshold corresponds to a leakage rate equal to 5 CLP. A fifth flow threshold corresponds to a leakage rate equal to 4 CLP. A sixth flow threshold corresponds to a leakage rate equal to 3 CLP. A seventh flow threshold corresponds to a leakage rate equal to 1 CLP. To summarize:

[0201]

[0202] Table 4: CLP of 1, 3 and 5

[0203] In some embodiments, the order of the flow thresholds may be changed based on the leak rate of the leak.

[0204] At block 804, similar to reference Fig.13 As depicted in block 704 of FIG. 8 , process 800 monitors TFR using one or more of the flow rate monitoring techniques described herein.

[0205] At block 806, process 800 determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a first flow threshold. If the first flow threshold is met, then at block 808, the process may indicate that the system is operating normally. The indication in block 808 or any other block of process 800 may be performed using any of the approaches described herein.

[0206] If the monitored TFR does not meet the first flow threshold, the process transitions to block 810, which determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a second flow threshold. If the second flow threshold is met (and the first flow threshold is not met), then at block 812, the process may indicate that an obstruction condition exists in the first fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the second fluid flow path and the third fluid flow path.

[0207] If the monitored TFR does not meet the second flow threshold, the process transitions to block 814 where it determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a third flow threshold. If the third flow threshold is met (and the first flow threshold and the second flow threshold are not met), then at block 816, the process may indicate that an obstruction condition exists in the second fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the first fluid flow path and the third fluid flow path.

[0208] If the monitored TFR does not meet the third flow threshold, the process transitions to block 818, which determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a fourth flow threshold. If the fourth flow threshold is met (and the first flow threshold, the second flow threshold, and the third flow threshold are not met), then at block 820, the process may indicate an obstruction condition exists in the first fluid flow path and the second fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the third fluid flow path.

[0209] If the monitored TFR does not meet the fourth flow threshold, the process transitions to block 822 where it determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a fifth flow threshold. If the fifth flow threshold is met (and the first through fourth flow thresholds are not met), then at block 824, the process may indicate that a blockage condition exists in the third fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the first fluid flow path and the second fluid flow path.

[0210] If the monitored TFR does not meet the fifth flow threshold, the process transitions to block 826 where it determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a sixth flow threshold. If the sixth flow threshold is met (and the first through fifth flow thresholds are not met), then at block 828, the process may indicate that a blockage condition exists in the first fluid flow path and the third fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the second fluid flow path.

[0211] If the monitored TFR does not meet the sixth flow threshold, the process transitions to block 830 where it determines whether the monitored TFR meets (e.g., substantially equals or exceeds) a seventh flow threshold. If the seventh flow threshold is met (and the first through sixth flow thresholds are not met), then at block 832, the process may indicate that an obstruction condition exists in the second fluid flow path and the third fluid flow path. The process may make this determination because, based on the thresholds being met, the process may determine that it is only detecting flow from the first fluid flow path.

[0212] At block 834, process 800 determines that any flow thresholds are not met and indicates a system occlusion state.

[0213] Although the example provided in conjunction with process 800 involves a system having a first wound dressing, a second wound dressing, and a third wound dressing, it should be noted that similar techniques may be performed for a system having any number of wound dressings.

[0214] Examples, embodiments, methods, processes, or devices of negative pressure wound therapy systems with calibrated leak paths are further provided in International Application No. PCT / EP2018 / 056494, entitled “MULTIPLE DRESSING NEGATIVE PRESSURE WOUND THERAPY SYSTEM WITH CALIBRATED LEAK PATHS” and filed on March 15, 2018, which is incorporated herein by reference in its entirety.

[0215] the term

[0216] Depending on the embodiment, certain operations, actions, events, or functions of any process described herein may be performed in a different order, may be added, combined, or omitted (e.g., not all practices of the process are necessary). In addition, in some embodiments, operations, actions, functions, or events may be performed simultaneously, for example, through multithreading, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially.

[0217] The processing of the various components of the system shown can be distributed on multiple machines, networks and other computing resources. In addition, two or more components of the system can be combined into fewer components. The various components of the system shown can be implemented in one or more virtual machines, rather than in a dedicated computer hardware system and / or computing device. Similarly, the data repository shown can represent physical and / or logical data storage, including, for example, a storage area network or other distributed storage systems. In addition, in some embodiments, the connection between the components shown represents the possible path of the data flow, rather than the actual connection between the hardware. Although some examples of possible connections are shown, any subset of the components shown can communicate with any other subset of the components in various embodiments.

[0218] Any patents, applications and other references mentioned above (including any documents that may be listed in the accompanying application documents) are incorporated herein by reference. If necessary, various aspects of the present disclosure can be modified to adopt the systems, functions and concepts of the various references described herein to provide further embodiments.

[0219] 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 features disclosed in this specification (including any accompanying claims, abstract and drawings), or all steps of any method or process so disclosed, may be combined in any combination, except for combinations where at least some of such features or steps are mutually exclusive. Protection is not limited to the details of any foregoing embodiments. Protection extends to any one novel feature or any novel combination of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or any one novel feature or any novel combination of the steps of any method or process so disclosed.

[0220] Although certain embodiments have been described, these embodiments are presented only as examples and are not intended to limit the scope of protection. In fact, the novel methods and systems described herein can be embodied in various other forms. In addition, various omissions, substitutions and changes in the form of the methods and systems described herein can be performed. It will be understood by those skilled in the art that in some embodiments, the actual steps taken in the process shown or disclosed may be different from the steps shown in the accompanying drawings. According to an embodiment, some of the above steps may be removed and other steps may be added. For example, the actual steps or step sequence taken in the disclosed process may be different from those shown in the figure. According to an embodiment, some of the above steps may be removed and other steps may be added. For example, the various components shown in the figure may be implemented as software or firmware on a processor, a controller, an ASIC, an FPGA or dedicated hardware. Hardware components such as a processor, an ASIC, an FPGA, etc. may include a logic circuit. In addition, 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.

[0221] Although the present disclosure includes certain embodiments, examples, and applications, those skilled in the art will appreciate that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments or uses and obvious modifications and equivalents thereof, including embodiments that do not provide all of the features and advantages described herein. Therefore, the scope of the present disclosure is not intended to be limited by the described embodiments and may be defined by the claims presented herein or claims presented in the future.

[0222] Conditional language, such as "may", "can", "might", or "could", unless otherwise expressly stated or understood in other ways in the context of use, is generally intended to express that certain embodiments include, while other embodiments do not include, certain functions, elements, or steps. Therefore, such conditional language is generally not intended to imply that one or more embodiments require features, elements, or steps in any way, or that one or more embodiments must include logic for determining whether these features, elements, or steps are included or executed in any particular embodiment with or without user input or prompting. The terms "include", "comprise", "have", etc. are synonymous and are used inclusively in an open-ended manner and do not exclude additional elements, features, actions, operations, etc. In addition, the term "or" is used in its inclusive sense (rather than 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. Similarly, the term "and / or", when referring to a list of two or more items, covers all of the following interpretations of the word: any one of the items in the list, all of the items in the list, and any combination of the items in the list. Furthermore, in addition to having its ordinary meaning, the term "each" as used herein may refer to any subset of a group of elements to which the term "each" is applied. Additionally, when used in this application, the words "herein," "above," "below," and words of similar meaning refer to this application as a whole and not to any particular portions of this application.

[0223] Unless expressly stated otherwise, linking language such as the phrase "at least one of X, Y, and Z" is understood in the context as generally used to indicate that an item, term, etc. can be X, Y, or Z. Thus, such linking language is generally not meant 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.

[0224] Language of degree as used herein, such as the terms "about," "approximately," "substantially," and "roughly" as used herein, refers to a value, amount, or feature that is close to a specified value, amount, or feature that still performs a desired function or achieves a desired result. For example, the terms "about," "approximately," "substantially," and "substantially" may refer to an amount that is within less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of a specified amount. As another example, in certain embodiments, the terms "substantially parallel" and "substantially parallel" refer to a value, amount, or feature that deviates from exact parallelism by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degrees.

[0225] Any of the embodiments described herein may be used with or without a can. Any of the dressing embodiments described herein can absorb and store wound exudate. The scope of the present disclosure is not intended to be limited by the description of certain embodiments, but rather by the claims. The language of the claims is to be interpreted broadly based on the language employed in the claims, and is not limited to examples described in this specification or during the prosecution of the application, which examples should be interpreted as non-exclusive.

Claims

1. A method of operating a negative pressure wound therapy system, the negative pressure wound therapy system comprising a negative pressure source for supplying negative pressure and a plurality of negative pressure wound therapy devices for a plurality of wound sites, wherein each of the plurality of negative pressure wound therapy devices comprises a bridge, the bridge comprising a fluid flow path and a leakage path, the fluid flow path being configured to fluidly couple the negative pressure source to a wound dressing placed over a wound site to provide negative pressure to the wound site, the leakage path having a controlled leakage port toward the wound site and being configured to fluidly connect to the wound dressing to provide gas from the controlled leakage port to the wound dressing, wherein the leakage path extends along the fluid flow path, and the fluid flow path and the leakage path are fluidly separated from each other within the bridge, the method comprising: determining the total flow rate in all fluid flow paths; and Based on a comparison between the determined total flow rate and at least one flow threshold, an indication of at least one operating state is provided.

2. The method of claim 1 , wherein providing an indication of the at least one operating state comprises: providing an indication that an obstruction condition exists in one or more fluid flow paths in response to determining that the total flow rate does not satisfy a first flow threshold of the at least one flow threshold; An indication that a normal operating condition exists is provided in response to determining that the total flow rate satisfies the first flow threshold.

3. The method of claim 2, wherein providing an indication of the at least one operating state further comprises: An indication that an obstruction condition exists in all fluid flow paths is provided in response to determining that the total flow rate does not satisfy a second flow threshold of the at least one flow threshold.

4. The method of claim 3, wherein the negative pressure source comprises a tank for collecting wound exudate, and providing the indication of the at least one operating state further comprises: An indication that the tank is full is provided in response to determining that the total flow rate does not satisfy a third flow threshold of the at least one flow threshold.

5. The method of any one of claims 1 to 4, wherein the method is performed by a controller of the negative pressure wound therapy system.

6. The method of any one of claims 2 to 4, wherein the first flow threshold corresponds to an expected flow rate in the fluid flow path.

7. The method of claim 6, wherein the expected flow rate corresponds to a flow rate in the fluid flow path under the normal operating conditions.

8. The method of any one of claims 1 to 4, wherein determining the total flow rate comprises measuring a speed of a motor operating the negative pressure source.

9. The method of claim 8, further comprising measuring a first plurality of motor speeds during a first time period and averaging the first plurality of motor speeds, the average being indicative of the total flow rate.

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