Negative pressure wound therapy

Abstract

Apparatuses and related aspects for providing reduced pressure to a tissue site are disclosed. The apparatus includes a negative pressure source configured to provide negative pressure from an inlet of the negative pressure source to a wound site via a first fluid flow path, an electronically controllable valve configured to release negative pressure from the wound site via a second fluid flow path, and a pressure sensor configured to measure a pressure level in the first fluid flow path or the second fluid flow path. The apparatus also includes control circuitry configured to execute an irrigation sequence adapted to increase an amount of exudate removed from the wound site.

Description

Technical Field

[0001] The embodiments disclosed herein generally relate to negative pressure wound therapy (NPWT). In particular, the embodiments disclosed herein relate to apparatus for providing decompression to a wound site, methods for controlling the apparatus for providing decompression to a wound site, and related computer program products, computer-readable storage media, and systems. Background Technology

[0002] Negative pressure wound therapy (NPWT) is a technique that promotes the healing of wounds, such as surgical wounds, acute wounds, and chronic wounds, by applying sub-atmospheric pressure (“negative pressure”) to the wound using a negative pressure pump. Wound healing is achieved by applying negative pressure (e.g., a “vacuum”) to the wound through dressings or coverings. This removes excess wound exudate, increasing blood flow to the area and promoting granulation tissue formation. NPWT also reduces external disturbance to the wound and removes excess fluid from the wound site. NPWT is suitable for a wide variety of wounds, such as open wounds, incision wounds, and skin grafts.

[0003] Historically, NPWT technology was primarily used for patients in hospital settings. However, recent product developments have enabled patients to use the technology in their home environments.

[0004] In a hospital setting, wounds to be treated are typically open cavity wounds, initially filled with wound packing materials such as gauze or foam. The wound can then be sealed with an adhesive membrane and connected to a negative pressure pump via a drainage tube or port. The size of the foam, gauze, and / or adhesive membrane can be adjusted and cut according to the size, shape, or type of wound. The dressing process is usually performed by caregivers. The negative pressure pumps used in such systems are typically large and often have a high capacity to handle large amounts of wound exudate.

[0005] In a home setting, portable NPWT devices that can be carried by the patient are generally preferred. Portable NPWT devices typically include an absorbent dressing configured to connect to a negative pressure source via tubing. The pump used in such devices is typically small in size and has a more limited capacity. NPWT systems that include absorbent dressings are also used in hospitals or nursing facilities, particularly for wounds with less exudation or that are “closed,” such as surgically closed incisions.

[0006] In some portable NPWT systems, dressings are used as the sole means of collecting wound exudate, while in other portable NPWT systems and NPWT systems suitable for treating wounds in a hospital setting, fluid collection devices, such as canisters, are arranged away from the wound site. In such systems, the canister serves as the primary device for collecting wound exudate.

[0007] Regardless of whether the NPWT system includes non-absorbent or absorbent dressings, or whether the application process is performed by a caregiver or the wearer in their home environment, there is room for improvement in this area. Exudative wounds not only cause significant discomfort and / or pain to the affected person but also present challenges for caregivers and other caregivers. Therefore, there is a need for new and improved NPWT systems that allow for efficient exudate delivery without unnecessarily increasing product complexity and cost. Summary of the Invention

[0008] The techniques disclosed herein are intended to mitigate, alleviate, or eliminate one or more of the aforementioned defects and disadvantages in the prior art in order to address various problems related to the transport of exudate at the wound site in NPWT systems.

[0009] The various aspects and implementations of the disclosed technology are defined below and in the appended independent and dependent claims.

[0010] The disclosed technology includes a device for providing negative pressure to a wound site. The device includes a negative pressure source, an electronically controllable valve, and a pressure sensor. The negative pressure source is configured to provide negative pressure to the wound site from its inlet via a first fluid flow path. The electronically controllable valve is configured to release negative pressure from the wound site via a second fluid flow path. The pressure sensor is configured to measure the pressure level in either the first or second fluid flow path. The device also includes a control circuit system operatively connected to the negative pressure source, the electronically controllable valve, and the pressure sensor. The control circuit system is configured to regulate the negative pressure provided to the wound site during multiple pressure regulation cycles, each pressure regulation cycle including a pressure regulation period and an irrigation period. The control circuit system is also configured to maintain the pressure level output by the pressure sensor between an upper and lower pressure value by activating and deactivating the negative pressure source during the pressure regulation period. The control circuit system is also configured to, during the rinsing period, activate a negative pressure source until a first pressure value is reached, open an electronically controllable valve in response to reaching the first pressure value, close the electronically controllable valve in response to reaching a second pressure value higher than the first pressure value, and activate the negative pressure source again until a target pressure value is reached. The target pressure value is a pressure value within a closed interval defined by the upper and lower pressure values.

[0011] Another aspect of the disclosed technology includes a computer-implemented method for operating a device for providing negative pressure to a wound site. The device includes a negative pressure source, an electronically controllable valve, and a pressure sensor. The negative pressure source is configured to provide negative pressure to the wound site from its inlet via a first fluid flow path. The electronically controllable valve is configured to release negative pressure from the wound site via a second fluid flow path. The pressure sensor is configured to measure the pressure level in either the first or second fluid flow path. Furthermore, the device is operable to regulate the negative pressure provided to the wound site within a plurality of pressure regulation cycles, each pressure regulation cycle including a pressure regulation period and a flushing period. The method includes maintaining the pressure level output by the pressure sensor between an upper pressure value and a lower pressure value by activating and deactivating the negative pressure source during the pressure regulation period. The method also includes activating the negative pressure source until a first pressure value is reached during the flushing period, opening the electronically controllable valve in response to reaching the first pressure value, closing the electronically controllable valve in response to reaching a second pressure value higher than the first pressure value, and activating the negative pressure source until a target pressure value is reached. Here, the target pressure value is the pressure value within a closed interval defined by the upper pressure value and the lower pressure value. This aspect of the disclosed technology possesses similar advantages and preferred features to other aspects.

[0012] Another aspect of the disclosed technology includes a computer program product comprising instructions that, when executed by a computing device for providing negative pressure to a wound dressing, cause the device to perform a method according to any of the embodiments disclosed herein. This aspect of the disclosed technology possesses similar advantages and preferred features to those in other aspects.

[0013] Another aspect of the disclosed technology includes a (non-transitory) computer-readable storage medium comprising instructions that, when executed by a computing device for providing negative pressure to a wound dressing, cause the device to perform a method according to any of the embodiments disclosed herein. This aspect of the disclosed technology possesses similar advantages and preferred features to those in other aspects.

[0014] As used herein, the term "non-transitory" is intended to describe computer-readable storage media (or "memory") that exclude the propagation of electromagnetic signals, but is not intended to otherwise limit the types of physical computer-readable storage devices covered by the phrase computer-readable media or memory. For example, the terms "non-transitory computer-readable media" or "tangible memory" are intended to cover types of storage devices that do not necessarily permanently store information, including, for example, random access memory (RAM). Program instructions and data stored on tangible computer-accessible storage media in non-transitory form can also be transmitted via transmission media or signals (e.g., electrical signals, electromagnetic signals, or digital signals), which can be transmitted via communication media such as networks and / or wireless links. Therefore, as used herein, the term "non-transitory" is a limitation on the medium itself (i.e., tangible media, not signals), rather than a limitation on the persistence of data storage (e.g., RAM and ROM).

[0015] Another aspect of the disclosed technology includes a wound treatment system comprising an apparatus according to any of the embodiments disclosed herein, a wound covering for creating a sealed space partially defined by the wound site, and a piping assembly defining a first fluid flow path and a second fluid flow path.

[0016] The disclosed aspects and preferred embodiments may be suitably combined with each other in any manner obvious to any person skilled in the art, such that one or more features or embodiments disclosed with respect to one aspect may also be considered as disclosed with respect to another aspect or embodiments of another aspect.

[0017] One advantage of some implementations is that, for dual-lumen negative pressure wound therapy systems, improved exudate transport from the wound site can be achieved. Therefore, due to the reduced amount of exudate at the wound site, treatment effectiveness can be improved. Furthermore, the risk of backflow into the exudate lumen is reduced.

[0018] One advantage of some implementations is that the system is more responsive to changes in conditions affecting the wound treatment system, thereby enabling the provision of more stable treatment and the robust maintenance of the desired negative pressure level at the wound site over time.

[0019] Further embodiments are defined in the dependent claims. It should be emphasized that the term "comprises" or "comprising," as used in this specification, is used to specify the presence of the stated features, elements, steps, or components. This does not preclude the presence or addition of one or more other features, elements, steps, components, or groups thereof.

[0020] These and other features and advantages of the disclosed technology will be further explained below with reference to the embodiments described herein. Attached Figure Description

[0021] The above aspects, features, and advantages of the disclosed technology will be more fully understood by referring to the following illustrative and non-limiting detailed description of exemplary embodiments of the present disclosure, taken in conjunction with the accompanying drawings, in which:

[0022] Figure 1 This is a schematic diagram of a wound treatment system according to some implementation methods.

[0023] Figure 2 This is a schematic diagram illustrating the change of negative pressure over time within multiple pressure regulation cycles according to some implementation methods.

[0024] Figure 3 This is a schematic diagram illustrating the change of negative pressure over time within multiple pressure regulation cycles according to some implementation methods.

[0025] Figure 4 This is a schematic diagram illustrating the change of negative pressure over time within multiple pressure regulation cycles according to some implementation methods.

[0026] Figure 5 This is a schematic diagram illustrating the change of negative pressure over time within multiple pressure regulation cycles according to some implementation methods.

[0027] Figure 6 It is a schematic flowchart representing a method for operating a device for providing negative pressure to a wound site according to some embodiments. Detailed Implementation

[0028] This disclosure will now be described in detail with reference to the accompanying drawings, in which some exemplary embodiments of the disclosed technology are illustrated. However, the disclosed technology may be implemented in other forms and should not be construed as limited to the exemplary embodiments disclosed. The exemplary embodiments disclosed are provided to fully convey the scope of the disclosed technology to those skilled in the art. The same reference numerals always refer to the same elements. Those skilled in the art will understand that the steps, services, and functions described herein can be implemented using separate hardware circuit systems, using software that works in conjunction with hardware circuit systems such as programmable microprocessors or general-purpose computers, using one or more application-specific integrated circuits (ASICs), using one or more field-programmable gate arrays, and / or using one or more digital signal processors (DSPs).

[0029] It will also be understood that, when this disclosure is described in terms of method, it can also be embodied in an apparatus comprising one or more processors and one or more memories coupled to one or more processors, wherein computer code is loaded to implement the method. For example, in some embodiments, one or more memories may store one or more computer programs that, when executed by one or more processors, cause the apparatus to perform the steps, services, and functions disclosed herein.

[0030] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It should be noted that when used in the specification and appended claims, unless the context clearly specifies otherwise, the terms "a," "an," "the," and "described" are intended to mean one or more elements. Thus, for example, a reference to "unit" or "the unit" may refer to more than one unit in some contexts. Furthermore, the words "comprising," "including," and "containing" do not exclude other elements or steps. It should be emphasized that the terms "comprises" / "comprising," when used in this specification, are used to specify the presence of the stated features, elements, steps, or components. This does not exclude the presence or addition of one or more other features, elements, steps, components, or groups thereof. The term "and / or" should be interpreted as also meaning "both" and alternatively. Similarly, "at least one of A and B" should be interpreted as only A, only B, or both A and B.

[0031] It will also be understood that although the terms first, second, etc., may be used herein to describe various elements or features, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of the embodiments, a first signal may be referred to as a second signal, and similarly, a second signal may be referred to as a first signal. Both the first signal and the second signal are signals, but they are not the same signal. The term "operationally connected" in the context of this disclosure should be understood to mean that entities or units "operationally connected" can send signals to each other and / or receive signals from each other.

[0032] As used herein, the term "in response to" can be interpreted, depending on the context, as meaning "when," "at," or "if." Similarly, the phrases "if determined," "when determined," or "in the case of," can be interpreted, depending on the context, as meaning "when determined," "in response to determination," "when the occurrence of an event is detected and identified," or "in response to the detection of an event." Therefore, the phrase "if X equals Y" can be interpreted, depending on the context, as "when X equals Y," "when determined to be Y," "in response to X equals Y," or "in response to the detection / determination of X equals Y."

[0033] Now turn to the attached image, and specifically to... Figure 1 The diagram schematically illustrates a wound treatment system 1 (sometimes simply referred to as "System" 1) according to some embodiments. The depicted wound treatment system 1 may be referred to as an "NPWT system" 1, a "decompression wound treatment system" 1, or a "negative pressure wound treatment system" 1. In particular, the depicted wound treatment system 1 may be referred to as a "dual-chamber" wound treatment system 1. The wound treatment system 1 includes means 10 for providing negative pressure to a wound site 27 (or otherwise referred to as a tissue site 27). The wound treatment system 1 also includes a wound covering 22 adapted to create a sealed space 23 at or around the user's wound, the sealed space 23 being partially defined by the wound surface (e.g., at the user's skin).

[0034] Furthermore, device 10 (also referred to as NPWT device 10 or pump device 10) uses a tubing assembly fluidly connected to wound dressing 22, the tubing assembly having a first conduit 21 that at least partially defines a first fluid flow path and a second conduit 41 that at least partially defines a second fluid flow path. The conduits 21, 41 can be any suitable flexible tubing made of an elastomer, polymer material, or any other suitable material with similar properties. The conduits 21, 41 can be connected to wound dressing 20, or more specifically to wound dressing 20 and wound covering 22, via suitable connectors 25. Connectors 25 can be adhesively or otherwise attached to wound covering 22. In particular, connectors 25 can be attached around an opening (not shown) formed in wound covering 22. Thus, the tubing assembly can include two separate tubes.

[0035] As used herein, the term "wound covering" should be interpreted broadly as any wound site component, such as a membrane sealing the periphery of wound site 27, wherein wound filler can be used to fill the wound volume prior to the application of such a wound covering. Wound covering may also refer to the backing layer of wound dressing 20, which includes additional layers such as absorbent layers and / or spacer layers.

[0036] The device 10 includes a negative pressure source 14 configured to provide negative pressure (i.e., subatmospheric pressure) from an inlet of the negative pressure source 14 to a wound dressing 20, a wound site 27, a sealed space 23, or a wound covering 22 via a first fluid flow path. The first fluid flow path (“exudate cavity”) is at least partially defined by a first conduit 21. The wound treatment system 1 also includes a second fluid flow path that fluidly connects the wound site or the sealed space 23 created by the wound covering 22 to the ambient atmosphere or a “fluid reservoir” (not shown) via an electronically controllable valve 40. The second fluid flow path (“air cavity”) is at least partially defined by a second conduit 41. Here, the fluid flow path from the inlet of the negative pressure source 14 to the wound site 27 can be interpreted as the first fluid flow path or the “exudate cavity,” while the fluid flow path from the wound site 27 via the valve 40 to the ambient atmosphere or the fluid reservoir can be interpreted as the second fluid flow path or the “air cavity.”

[0037] The negative pressure source 14 is indicated as “VP” (“vacuum pump”) in the accompanying drawings. In some embodiments, the negative pressure source 14 includes a negative pressure pump adapted, together with a motor, to establish negative pressure when the negative pressure source 14 is in operation (i.e., when it is active or simply “on”). The negative pressure source may include any type of pump and motor that is biocompatible or otherwise adapted for use in an NPWT environment and capable of maintaining or drawing a sufficient therapeutic vacuum level (i.e., negative pressure level). Preferably, the negative pressure level to be achieved is in the range of about -20 mmHg to about -300 mmHg. In some embodiments, a negative pressure range of about -80 mmHg to about -140 mmHg is used. In some embodiments, a negative pressure range of about -115 mmHg to about -135 mmHg is used. In some embodiments, the negative pressure pump is a diaphragm pump, a peristaltic pump, a piezoelectric pump, etc., wherein the motor causes a moving part to draw fluid from the wound site 27.

[0038] In the context of this disclosure, it should be understood that the terms “negative pressure,” “subatmospheric pressure,” “decompression,” or even “vacuum,” as used interchangeably herein, generally refer to a pressure less than the local ambient pressure, such as the ambient pressure in the local environment outside the sealed treatment environment provided by the wound covering 22 or dressing 20. In many cases, the local ambient pressure can also be the atmospheric pressure at which the patient is located. Therefore, “negative pressure” can be understood as the pressure difference between the ambient pressure and the pressure under the wound covering, where the ambient pressure is typically set to 0 mmHg. Unless otherwise indicated, the pressure values ​​stated herein are gauge pressures. Similarly, references to an increase in negative pressure generally refer to a decrease in pressure, and a decrease in negative pressure generally refer to an increase in pressure.

[0039] Furthermore, in some embodiments, device 10 includes a can 16 fluidly connected to negative pressure source 14. Can 16 may be formed of, for example, molded plastic and may be a removable component of device 10. Additionally, can 16 may be at least partially transparent / semi-transparent to allow observation of the interior of can 16, thereby helping the user determine the remaining capacity of can 16. As used herein, the term "fluid connection" should be interpreted broadly and may include any form of tubing, conduit, or channel that provides fluid connection / communication between two components, such as between can 16 and negative pressure source 14 or between can 16 and wound dressing 20.

[0040] In some embodiments, tank 16 includes an inlet port 28 for allowing connection to conduit 21. Inlet port 28 may also be formed elsewhere on device 10, yet still fluidly connected to tank 16. The connection between inlet port 28 and conduit 21 is a sealed connection, thus ensuring no leakage occurs at inlet port 28 during normal operation of device 10. Conduit 21 is preferably detachably connected to inlet port 28 by conventional means including friction fits, bayonet connections, snap-fit ​​connections, barbed connectors, etc. Inlet port 28 may be molded / formed from the same material as forming tank 16 and / or simultaneously molded / formed with forming tank 16. A similar sealed connection (e.g., using a flange insulating seal / “O-ring”) is formed between tank 16 (at outlet port 29) and negative pressure source 14. Tank 16 may form part of a first fluid flow path.

[0041] In some embodiments, the device includes a housing 19 surrounding the negative pressure source 14. The can 16 may be detachably connected to the housing 19 including the negative pressure source 14, thereby allowing, for example, the removal of a full can and replacement with an empty (new) can. In such embodiments, it may be desirable to provide, for example, some form of engagement mechanism to the can 16 and the housing 19, for securing the can 16 to the housing so that the can 16 cannot be accidentally removed from the housing 19. In one embodiment, the engagement mechanism may include a pair of flexible protrusions extending from the can 16 and adapted to engage, for example, corresponding locking recesses provided on the housing 19.

[0042] However, in some embodiments, the wound treatment system 1 is a canisterless wound treatment system (not shown), in which wound exudate is collected in the absorbent layer of the wound dressing 20, etc. In such embodiments, as will be readily understood by those skilled in the art, the fluid flow path from the wound dressing 20 to the negative pressure source 14 is provided with one or more suitable filters (not shown), said one or more suitable filters being adapted to allow gas to flow from the wound site 27 to the negative pressure source 14 and to block liquid from flowing from the wound site 27 to the negative pressure source 14.

[0043] In some embodiments, device 10 includes a power source, such as battery 13, for powering device 10. Battery 13 may preferably be rechargeable, but may alternatively be arranged as disposable and therefore need to be replaced once discharged. In some embodiments, specially adapted battery packs may be used. Device 10 may be of single-use type (allowing use during a single treatment duration) or multiple-use type (allowing use during several different treatment sessions).

[0044] Furthermore, device 10 includes a pressure sensor 15a arranged in fluid connection with a second fluid flow path and / or a pressure sensor 15b arranged in fluid connection with a first fluid flow path. In some embodiments, device 10 may alternatively or additionally include sensors arranged at or near the wound site 27 (e.g., in the wound dressing 20 or connector 25). Thus, device 10 includes at least one pressure sensor 15a configured to measure pressure levels in the second fluid flow path, the first fluid flow path, and / or the wound site. However, it should be noted that regardless of the location of the pressure sensors (e.g., fluidly connected in the first or second fluid flow path), since this is a closed system, the pressure measured by pressure sensors 15a, 15b is considered representative of the pressure level at the wound site 27. Therefore, in some embodiments, device 10 includes pressure sensors 15a, 15b arranged to monitor / measure / detect the pressure level at the wound site 27. In other words, the device 10 includes pressure sensors 15a and 15b, which are arranged to monitor / measure / detect pressure levels in a first fluid flow path or a second fluid flow path, wherein the monitored / measured / detected pressure levels represent the pressure levels at the wound site 27.

[0045] In some embodiments, the device 10 includes a single pressure sensor 15a configured to measure / monitor the pressure level in the second fluid flow path. In the depicted embodiment, the pressure sensor 15a is arranged downstream of the electronically controllable valve 40 within the housing (i.e., from the valve 40 toward the wound site). However, as will be readily understood by those skilled in the art, one or more pressure sensors 15a can be arranged in any other suitable location to sense or detect pressure within the second fluid flow path (“air chamber”). In some embodiments, the single pressure sensor is arranged in other suitable locations, for example, connected to the first fluid flow path (see [link to relevant documentation]). Figure 1 (See attached figure 15b) or placed in wound dressing 20.

[0046] In some embodiments, device 10 includes one or more pressure sensors arranged in fluid connection to the inlet of negative pressure source 14, tank 16, and / or sealed space 23. Figure 1 In the depicted embodiment, in addition to the pressure sensor 15a arranged in fluid connection with the second fluid flow path, the device 10 also includes a pressure sensor 15b arranged in the fluid flow path between the canister 16 and the negative pressure source 14 (i.e., in fluid connection with the first fluid flow path). However, as will be readily understood by those skilled in the art, the additional pressure sensor 15b can be located at any other suitable location to sense or detect pressure within the fluid flow path between the negative pressure source 14 and the wound site 27. For example, the additional pressure sensor 15b can be arranged within the canister 16, within the wound dressing 20, or within the connector 25.

[0047] The device 10 also includes a control circuitry system “CTRL” 11 (also referred to as a “control unit”, “controller”, etc.) operatively connected to the battery 13, the negative pressure source 14, the electronically controlled valve 40, the first pressure sensor 15a, and the second pressure sensor 15b. The control circuitry system 11 is configured to control the operation of the negative pressure source 14 and the electronically controlled valve 40. The control circuitry system 11 may include a microprocessor, a microcontroller, a programmable digital signal processor, or other programmable devices. The control circuitry system 11 may also include, or alternatively include, an application-specific integrated circuit (ASIC), a programmable gate array or programmable array logic, a programmable logic device, or a digital signal processor. Where the control circuitry system 11 includes a programmable device such as a microprocessor, microcontroller, or programmable digital signal processor as mentioned above, the control circuitry system 11 may also include computer-executable code that controls the operation of the programmable device. Therefore, in some embodiments, the control circuitry system 11 includes one or more processors and a memory, wherein the memory contains instructions executable by the processors, thereby operating the device 10 to perform any of the method steps or functions disclosed herein. In the current context, the term "electronically controllable" should be understood as meaning that an "electronically controllable" unit or component can be controlled by electrical signals (control signals), and in particular by electrical signals output from the control circuit system 11.

[0048] During use of the device 10, a wound covering 22 is placed over the user / patient's wound site 27, thereby forming a sealed space 23. The tubing assembly includes a first tubing 21 for fluidly connecting the wound covering 22 to the inlet port 28 of the device 10; and a second tubing 41 (at least partially defining a second fluid flow path) isolated from the surrounding atmosphere by a closing valve 40. The device 10 is then activated, for example by the user pressing a start / pause button 31 on the user interface 60 of the device 10, which activates the negative pressure source 14. Alternatively, this activation can be initiated via an external device 50 connected to the system 1. The external device 50 is further described below. When activated and the valve 40 is closed, the negative pressure source 14 begins to expel air through the tank 16, the inlet port 28, the tubing 21, and the sealed space 23 formed by the wound covering 22. Therefore, a negative pressure is generated within the sealed space 23. Figures 2 to 5 As shown, this initial venting of air after the activation device 10 can be referred to as “decompression”. The initial venting of air (i.e., “decompression”) can continue until a set pressure value (e.g., -125 mmHg) is reached. In some embodiments, the control circuitry 11 is configured to control the negative pressure source 14 to establish and maintain a negative pressure level (e.g., as measured by pressure sensors 15a, 15b) within a negative pressure range. The negative pressure range can be, for example, -20 mmHg to -300 mmHg, -80 mmHg to -180 mmHg, -100 mmHg to -150 mmHg, -110 mmHg to -140 mmHg, -115 mmHg to -135 mmHg, or any suitable subrange thereof (e.g., -80 mmHg to -100 mmHg). The negative pressure range can be selected, for example, based on the type of wound and / or the patient.

[0049] If fluid has formed at wound site 27, this fluid can be at least partially "drawn" from the wound site, through conduit 21, inlet port 28, and into canister 16. The amount of fluid (potentially defined as exudate) drawn from the wound and collected in canister 16 will depend on the type of wound being treated, the duration of treatment, and the type of wound dressing 20 used. For example, if an absorbent dressing is used, the fluid can be absorbed and collected in both canister 16 and wound dressing 20, while if a non-absorbent or low-absorbent dressing is used, most or all of the fluid from wound site 27 can be collected in canister 16. A suitable filter element (not shown) is typically arranged at outlet port 29 of canister 16 to ensure that fluid is not allowed to pass from canister 16 to negative pressure source 14.

[0050] The control circuitry 11 is also configured to control the operation of the electronically controllable valve 40 to release negative pressure from the wound site via a second fluid flow path (or "air chamber") 41. In other words, the control circuitry 11 is configured to open the electronically controllable valve 40 when sub-atmospheric pressure exists beneath the wound covering 22 to introduce fluid (e.g., air) into the wound site 27. This operation may also be referred to as "flushing." Figure 1 The wound treatment system 1 depicted does not have any “controlled leakage flow,” thus posing the risk that once a negative pressure is established under the wound dressing 22, the device 10 will be unable to draw any “exudate” from the wound site 27 to the canister 16, or at least only a suboptimal amount of “exudate,” due to the lack of airflow through the system 1. Therefore, in order to draw the desired amount of wound exudate from the wound site 27, fluid (e.g., air from the ambient atmosphere) is controllably introduced by opening the electronically controlled valve 40 at defined time intervals or in response to pressure measurements. Typically, once sufficient fluid has been introduced (e.g., in response to a first fluid flow path, a second fluid flow path, and / or a lower negative pressure threshold—i.e., a higher pressure threshold—reached within the wound site 27), the control circuitry 11 is configured to close the electronically controlled valve 40 and activate the negative pressure source 14. However, in some embodiments, the negative pressure source 14 may be active for at least some of the duration during which the electronically controlled valve 40 is open.

[0051] The ability to controllably “flush” system 1 by injecting air via electronically controllable valve 40 provides the advantage of a longer pressure regulation cycle (also known as NPWT cycle), which reduces the opening time of negative pressure source 14 and thus reduces the energy consumption of device 10.

[0052] The device 10 may also include an air filter (not shown) disposed in the second fluid flow path to restrict airflow when the electronically controllable valve 40 is open. In some embodiments, the air filter comprises a hydrophobic and porous material, wherein the pore size is configured to allow flow in the range of 50 ml / s to 120 ml / s (e.g., 60 ml / s to 100 ml / s) when the valve 40 is opened after a negative pressure is established under the wound dressing 20. Preferably, the pore size of the filter is measured in an uncompressed state. In some embodiments, the air filter comprises polyethylene or sintered polyethylene. When the valve 40 is open (i.e., during “rinsing”), the air filter can also be used to reduce the risk of contaminants entering the wound site 27. The air filter may be disposed in a conduit 41 that at least partially defines the second fluid flow path. The air filter may be disposed upstream of the valve 40 (i.e., between the valve 40 and the inlet of ambient air) or downstream of the valve 40, for example, between the valve and the pressure sensor 15a.

[0053] In some embodiments, during use, the control circuit system 11 is configured to operate in multiple pressure regulation cycles (T... CYC The pressure regulation cycle (T) provides negative pressure to the wound site. Generally, the pressure regulation cycle (T) CYC The term "pressure regulation period" can be understood as including at least a "pressure regulation period" and a "rinsing period". In other words, device 10 can operate in both "pressure regulation mode" and "rinsing mode". During the "pressure regulation period", control circuitry 11 is configured to operate negative pressure source 14 to maintain the negative pressure level within the appropriate negative pressure range illustrated above. In other words, during the "pressure regulation period", electronically controllable valve 40 is closed, and negative pressure source 14 is operated to maintain the desired negative pressure level at wound site 27.

[0054] During the "flushing period," the control circuitry 11 is configured to open the electronically controllable valve 40 to introduce fluid (e.g., air from the ambient atmosphere) into the wound site 27, close the valve 40, and activate the negative pressure source 14 to aspirate wound exudate from the wound site, potentially re-establishing a sufficient negative pressure level. Therefore, the flushing period temporarily reduces the negative pressure at the wound site 27 (i.e., temporarily increases the pressure). Pressure regulation cycles may include a pressure regulation period followed by a flushing period (see, for example...). Figure 2 or Figure 4 The flushing period is followed by a pressure regulation period (see example). Figure 3 or Figure 5 ).

[0055] The duration of the pressure regulation period and the flushing period, and therefore the pressure regulation cycle (T). CYC The duration of the pressure regulation cycle (T) can be fixed (i.e., time-controlled) or dynamically controlled based on pressure measurement. CYC The duration of the pressure regulation cycle (T) can also be dynamically controlled based on the total treatment time, allowing the pressure regulation cycle (T) to be adjusted. CYC The pressure regulation period is shorter during the initial phase of treatment than during the later phase. Furthermore, in some embodiments, the duration of the pressure regulation period and the flushing period, and therefore the pressure regulation cycle (T... CYC The duration of the flushing can be controlled based on pressure measurement combined with time control. For example, during a flushing period, control circuitry 11 can be configured to open the valve until a pressure level is reached (e.g., measured by sensors 15a, 15b) or for 2 seconds, whichever occurs first. Therefore, the time control aspect can limit the maximum duration of each period, while detecting certain pressure levels can shorten the duration. See below for reference. Figures 2 to 5 Further details are provided regarding pressure regulation cycles, pressure regulation periods, and flushing periods.

[0056] Next, device 10 utilizes a flushing algorithm or flushing sequence adapted to increase the amount of exudate removed (e.g., delivered to canister 16) from wound site 27 during each "flushing" compared to previously known solutions. More specifically, the flushing sequence begins with a depressurization (i.e., an increase in negative pressure) until a first set pressure value 202 (P1) is reached. Once the first set pressure value 202 (P1) is reached, pump 14 is shut off and valve 40 is opened and remains open until a second set pressure value 203 (P2) is reached, thereby increasing the pressure at wound site 27 (i.e., reducing negative pressure). However, pump 14 may remain open for an initial portion of the time after valve 40 is opened.

[0057] When the second set pressure value 203 (P2) is reached, valve 40 closes again, and pump 14 restarts until the target pressure value 204 (P2) is reached. TARGET Until then. However, here, some overlap can be applied between the start-up of pump 14 and the closing of valve 40, so that pump 14 is started before valve 40 is closed. Target pressure value 204 (P) TARGET ) is determined by the upper and lower limits used during the pressure regulation period (in Figures 2 to 5 The described embodiments are pressure values ​​within the range defined as -115 mmHg and -135 mmHg. In some embodiments, the pressure can be based on one or more previous pressure adjustment cycles (T). CYC The target pressure value of 204 (P) is set by the average pressure value of the pressure or the average pressure value of one or more previous pressure conditioning periods. TARGET ).

[0058] By depressurizing before opening valve 40, more air can be introduced into the system, and thus more exudate can be removed from wound site 27, while maintaining pressure within therapeutic limits during the irrigation sequence. Without initial depressurization, it might be necessary to allow pressure to increase to a higher value (i.e., reduce negative pressure to a lower value) to achieve a similar effect, potentially pushing pressure at the wound site beyond the desired therapeutic limits (e.g., limits applied during pressure regulation). Furthermore, by performing irrigation at lower pressure (achieved through depressurization at the start of the irrigation sequence), air can be introduced into the system at a higher rate, thereby reducing the duration of the irrigation sequence. Additionally, if the irrigation sequence is to adhere to the pressure limits used during pressure regulation, the irrigation sequence may be ineffective if the pressure is close to the upper pressure limit at the start of the sequence, as no significant amount of air is introduced into the system.

[0059] Furthermore, a target value of 204 (P) is set based on the average pressure value of one or more previous pressure regulation cycles or one or more previous pressure regulation periods. TARGET Completing the flushing sequence increases the likelihood of maintaining the desired negative pressure level for an extended period, as the device 10 is more responsive to temporary conditions that may occur between pressure regulation cycles, such as an increase or decrease in leakage.

[0060] Therefore, device 10 includes a control circuit system 11, which is configured to operate in multiple pressure regulation cycles (T... CYC The pressure is adjusted to provide negative pressure to the wound site 27, and each pressure adjustment cycle includes a pressure adjustment period and an irrigation period.

[0061] During the pressure regulation period, the control circuit system 11 is configured to maintain the pressure level output by pressure sensors 15a and 15b between an upper pressure value and a lower pressure value by activating and deactivating the negative pressure source 14. In other words, during the pressure regulation period, the control circuit system 11 is configured to maintain a pressure level at the wound site 27 between an upper pressure value and a lower pressure value by activating and deactivating the negative pressure source 14. The upper and lower pressure values ​​can be, for example, -80 mmHg and -140 mmHg, -100 mmHg and -140 mmHg, -115 mmHg and -135 mmHg, -120 mmHg and -135 mmHg, or any other suitable negative pressure range. Figures 2 to 5 In the depicted embodiment, the upper pressure value and the lower pressure value are set to -115 mmHg and -135 mmHg, respectively. The terms "pressure level" and "pressure value" are used interchangeably herein and are sometimes mixed to increase readability when referring to one or the other. As previously stated, because this is a closed system (closed fluid loop), even though pressure sensors 15a and 15b are arranged to measure the pressure level in the first fluid flow path or the second fluid flow path, the pressure level output by pressure sensors 15a and 15b is considered to represent the pressure level at the wound site 27.

[0062] During the pressure regulation period, the control circuit system 11 can be configured to activate the negative pressure source 14 in response to the pressure level (such as the pressure sensor output) reaching the upper pressure value 205, and in response to the pressure level (such as the pressure sensor output) reaching a certain desired pressure value (e.g., as...). Figure 3 The negative pressure source 14 is deactivated when the pressure level (the intermediate value between the upper and lower pressure values ​​shown) is reached. Alternatively, the control circuit system 11 can be configured to activate the negative pressure source 14 in response to the pressure level (such as the pressure sensor output) reaching the upper pressure value 205, and deactivate the negative pressure source 14 in response to the pressure level (such as the pressure sensor output) reaching the lower pressure value. Figure 5(As shown).

[0063] The pressure conditioning period can be any suitable length required for the applicable scenario and can be specified, for example, based on the patient, wound type, and / or any other relevant circumstances. In some implementations, the length of the pressure conditioning period ranges from 5 min to 120 min, such as 20 min, 30 min, 40 min, 60 min, or 90 min. As mentioned above, the length of the pressure conditioning period does not have to be static but can be shorter, for example, during the initial portion of the treatment cycle (e.g., 10 min) and longer (e.g., 40 min) during the final portion of the entire treatment cycle.

[0064] In some implementations, the control circuitry 11 is configured to start / reset the counter / timer once the flushing period has been completed. Then, once the counter or timer reaches a threshold (e.g., zero), the device 10 enters a flushing period (flushing mode) and then resets the counter / timer again at the end of the flushing period. The counter / timer can be reset to different values ​​or triggered with different values ​​based on the total operating time of the device 10 (i.e., the time elapsed since the initial startup of the device 10). For example, the counter / timer can be set to: 10 minutes for the first 24 hours after initial startup; 20 minutes for the subsequent 24 hours after initial startup (i.e., between 24 and 48 hours after initial startup); and then 30 minutes from 48 hours after initial startup until the entire treatment cycle is completed.

[0065] Next, during the rinsing period, the control circuit system 11 is configured to activate the negative pressure source 14 (e.g., Figures 2 to 5 (As indicated by reference numeral 201 in the accompanying drawings), until a first pressure value 202 (P1) is reached (output by a pressure sensor). During this initial portion of the flushing sequence, the electronically controllable valve 40 is preferably closed. Then, in response to reaching the first pressure value 202 (P1) (as output by the pressure sensor), the control circuitry 11 is configured to open the electronically controllable valve 40 and deactivate the negative pressure source 14.

[0066] Furthermore, in response to reaching a second pressure value 203 (P2) higher than the first pressure value 202 (P1) (output by the pressure sensor), the control circuit system 11 is configured to close the electronically controllable valve 40 and activate the negative pressure source 14 until the target pressure value 204 (P2) is reached. TARGET (Output from the pressure sensor). Here, the target pressure value is 204 (P). TARGET The target pressure (P) is the pressure value within a closed interval defined by the upper and lower pressure values ​​(from the pressure regulation period). In other words, the target pressure value (P) TARGET) is set to a value between the boundary pressure values ​​used during the pressure regulation period (in Figures 2 to 5 The described implementation is between -115 mmHg and -135 mmHg.

[0067] As will be readily understood by a technician, the first pressure value 202 (P1) is a pressure value lower than the upper pressure value from the pressure regulation period. In some cases, the first pressure value 202 (P1) may be lower than the pressure level reached at the end of the pressure regulation period, but this is not necessarily the case, as the pressure level reached at the end of the pressure regulation period may be consistent with the first pressure value 202 (P1). For example, in cases where system 1 does not exhibit leakage and the pressure level remains at the lower pressure value of the pressure regulation period throughout its duration, while the first pressure value 202 (P1) is set equal to the lower pressure value of the pressure regulation period. Another possibility is, for example, if the negative pressure source 14 is activated during the end of the pressure regulation period, just before the start of the flushing period, and any unwanted leakage may not have had time to occur or take effect before the start of the flushing period.

[0068] Therefore, in some cases, the activation of the negative pressure source 14 can be omitted, or it can occur only for a very short period of time, depending on the specific implementation (e.g., depending on whether the pressure level output by the pressure sensor is compared with the first pressure value 202 (P1) before or after any potential activation of the negative pressure source 14). However, in most practical cases, it is assumed that some undesirable leakage will always exist in system 1. Furthermore, the first pressure value 202 (P1) can be understood as a set pressure value, meaning that it is a preset or predefined pressure value. Similarly, the second pressure value 203 (P2) can be understood as a set pressure value, meaning that it is a preset or predefined pressure value.

[0069] It should be noted that even in Figures 2 to 5 In the described embodiments, the first pressure value 202 (P1) and the second pressure value 203 (P2) are set or selected to be the same as the upper and lower pressure values ​​during the pressure regulation period. The first pressure value 202 (P1) and the second pressure value 203 (P2) can also be set independently and can be different from the upper and lower pressure values ​​during the pressure regulation period. Therefore, in some embodiments, the first pressure value 202 (P1) is lower than the lower pressure value. In some embodiments, the second pressure value 203 (P2) is higher than the upper pressure value.

[0070] The term "responding to reaching a pressure value" can be understood as "responding to a pressure level reaching or exceeding a pressure value as determined by the output of the pressure sensor over time," "responding to the pressure sensor detecting a pressure level equal to the pressure value," or "responding to a pressure level reaching or exceeding a pressure value as measured by the pressure sensor." Naturally, the pressure level does not need to be precisely equal to the pressure value (the first pressure value and the second pressure value) to trigger the actuation of pump 14 or valve 40. As will be readily understood by those skilled in the art, a pressure level exceeding an applied threshold may be sufficient, for example, when the sampling rate of the pressure sensor is insufficient to actually record an accurate pressure value at every moment. For example, the term "responding to reaching a first pressure value 202 (P1)" can be interpreted as "responding to the pressure sensor detecting a pressure level at or below the first pressure value 202 (P1)." Similarly, the term "responding to reaching a second pressure value 203 (P2)" can be interpreted as "responding to the pressure sensor detecting a pressure level at or above the second pressure value 203 (P2)."

[0071] Furthermore, the terms "reached" or "exceeded" regarding pressure values ​​should be understood as indicating that a trigger is considered detected when it can be concluded that an applicable threshold or set value has been reached. For example, suppose the initial pressure value is -135 mmHg, and the pressure level starts at -120 mmHg when pump 14 is activated. Then, in some scenarios, the pressure sensor might detect a pressure level of -134.9 mmHg, and in subsequent samples, -135.1 mmHg. In such a scenario, the measurement / detection of -135.1 mmHg is considered to satisfy the "response to reaching the first pressure value" trigger.

[0072] Next, in some embodiments, a target pressure value 204 (P) is set based on the pressure levels measured by pressure sensors 15a and 15b over a previous time period. TARGET In other words, previous pressure measurements affected the target pressure value of 204 (P). TARGET What value is it set to?

[0073] In some implementations, the target pressure value is 204 (P). TARGET The setting is based on the average pressure level measured by pressure sensors 15a and 15b during a previous time period. The previous time period can be any time period, such as the last 30 minutes, the last 60 minutes, etc. In some embodiments, the previous time period includes one or more previous pressure regulation periods. However, in some embodiments, the previous time period includes one or more previous pressure regulation cycles (T). CYCTherefore, the preceding time period may include the preceding pressure regulation period (i.e., including the pressure regulation period while excluding the flushing period), or it may include the preceding pressure regulation cycle (i.e., including both the pressure regulation period and the flushing period).

[0074] However, in some embodiments, the time period extends from the initial pump-down following the initial startup of device 10 until the negative pressure source 14 is activated during the flushing period to reach the first pressure value. (See also...) Figures 2 to 5 This will include the time from reference numeral 210 to reference numeral 201 for each flushing cycle. However, in some embodiments, this may include the time from the initial start of device 10 (i.e., from...). Figures 2 to 5 (time t0) until the pump is started at the beginning of each flushing period (i.e., until...) Figures 2 to 5 The time (reference numeral 201 in the attached figure). However, in the embodiment where the pressure regulation cycle begins with the flushing period ( Figure 3 and Figure 5 In the target pressure value of 204 (P), TARGET It can be set to the middle value between the upper and lower pressure values ​​during the first flushing period.

[0075] The purpose of pressure regulation and general NPWT is to maintain a desired pressure level at the wound site, denoted as P below. DES For NPWT systems (“single-chamber” systems) with constant leakage flow, this is typically achieved by regulating the pressure to the desired pressure level (P0). DES The pressure is achieved between two pressure thresholds around the wound site. However, for systems without a constant leaking airflow (“dual-chamber” systems), device 10 is rarely or never adjusted, meaning that the actual pressure level at the wound site can deviate from the desired pressure level (Pw) over a longer period of time. DES To reduce this offset, this paper proposes to reduce the pressure from the target pressure value (P) for each pressure regulation period. TARGET Initially, the target pressure value depends on one or more previous pressure regulation cycles (T). CYC The pressure level. As mentioned earlier, the pressure regulation cycle can be defined as the time interval between the end of a flushing period and the end of a subsequent flushing period.

[0076] Target pressure value (P) TARGET The following formula can be used to calculate after each pressure regulation cycle.

[0077]

[0078] Downforce value ≤ P TARGET ≤Upward pressure value

[0079] Here, PAVG P is the average pressure measured by the pressure sensor for the previous pressure regulation cycles, N is the number of pressure regulation cycles counted so far, and P is the average pressure. TARGET It is the target pressure value as described above, and P DES The device 10, as described above, is configured to maintain the desired pressure level during treatment. Furthermore, the target pressure value (P...) TARGET It is also constrained by boundary conditions defined by the upper and lower pressure values ​​used during the pressure regulation period. In other words, the target pressure value is "capped" by the upper and lower pressure values ​​to ensure safe operation of the device. Therefore, even if the formula outputs the target pressure value (P) outside the boundary... TARGET ), target pressure value (P) TARGET The mean pressure value (P) was also simply set to the closest boundary value. AVG This can be obtained by summing the stress samples detected / obtained during the relevant time period and dividing the sum by the number of samples.

[0080] As is readily understood by a technician, if one only wishes to set the target pressure value (P) based on the average pressure of a (direct) single previous pressure regulation cycle... TARGET Then the coefficient N is simply set to 1, and P AVG This is the average pressure of that pressure regulation cycle. Similarly, if you wish to regulate for all previous pressure regulation cycles since the start of treatment, then N is simply set to the number of pressure regulation cycles that have been performed so far, and P... AVG It is the average pressure over those pressure regulation cycles. Only review one or two pressure regulation cycles to set the target pressure value (P). TARGET One advantage of this approach is that the system is more responsive and can therefore adapt quickly to temporary changes it experiences. However, one advantage of reviewing longer time periods (i.e., multiple pressure regulation cycles) is that the system is more robust and stable.

[0081] Furthermore, in some embodiments, during the flushing mode, the negative pressure source 14 is activated until the target pressure value 204 (P) is reached. TARGET (As output by a pressure sensor) occurs before the electronically controllable valve 40 is closed. Therefore, a smoother pressure curve can be achieved, reducing the risk of patient discomfort from rapidly changing pressure levels. This is, for example, in... Figure 4As shown, the curve around the second pressure value 203 (P2) flattens out. Furthermore, when the pressure changes at a slower rate, it allows for better control of the pressure level, thereby reducing the risk of extending beyond the permissible pressure threshold. In some embodiments, a similar procedure is applied around the first pressure value 202 (P1), meaning that after valve 40 is opened in response to reaching the first pressure value 202 (P1) and / or after valve 40 is opened before reaching the first pressure value 202 (P1), the negative pressure source 14 remains active (open) for a period of time.

[0082] The timing of activating the negative pressure source 14 and opening the electronically controlled valve 40 can depend on the system's configured flow rate. In other words, this may depend on the rate at which pump 14 draws fluid from the wound site and the rate at which air is introduced into the system when the valve opens. In some embodiments, valve 40 may be opened to a lesser extent during some or all of the "overlapping periods," and / or pump 14 may operate at a reduced rate (e.g., by applying a reduced voltage) during some or all of the "overlapping periods."

[0083] Furthermore, in some embodiments, device 10 also includes a user interface 60 comprising one or more light-emitting diodes (LEDs) 62. Control circuitry 11 is operatively connected to the user interface 60 and is also configured to activate at least one of the LEDs 62 in response to the negative pressure source 14 being activated more than a first number during a pressure regulation period. The first number can be interpreted as a set threshold and can be, for example, 5, 8, or 10. However, the first number can depend on a set length of the pressure regulation period, such that the first number is higher for longer pressure regulation periods and lower for shorter pressure regulation periods.

[0084] By calculating the number of times pump 14 is started during the pressure regulation period, leak detection functionality can be effectively integrated into device 10 in a simple manner. More specifically, if the pump is started "too frequently" in a dual-chamber system, this can be used as an indicator of the presence of unwanted leaks in system 1. Unwanted leaks may be due, for example, to improperly applied wound covering 22, tears or holes in the piping or wound covering 22, a faulty valve 40, and / or leaks in the connections between the piping and other components. Figure 5 An example of a leak detection function is shown, in which pump 14 is activated during the third pressure regulation cycle. Figure 5 The leak (reference numeral 205) is detected more frequently than in other pressure regulation cycles. By activating one or more LEDs 62, the user or caregiver can be notified of a detected leak and directed to check System 1 for any apparent leaks.

[0085] Furthermore, in some embodiments, device 10 includes a communication interface 56 having at least one antenna and at least one transceiver operatively connected to the at least one antenna. Control circuitry system 11 can therefore be operatively connected to communication interface 56 and is also configured to transmit signals to external device 50 in response to the negative pressure source 14 being activated more than a first number during a pressure regulation period.

[0086] Communication interface 56 may include suitable components (e.g., transceivers, antennas, filters, power amplifiers, etc.) with suitable communication protocols (e.g., Wi-Fi, Bluetooth, Bluetooth Low Energy (BLE), Zigbee, etc.) to establish a connection with external device 50 and to transmit and receive wireless signals from external device 50. Therefore, communication interface 56 is configured to transmit and receive wireless signals from external handheld device 50. More specifically, communication interface 56 includes one or more transceivers and one or more antennas connected to the transceivers. The transceivers are correspondingly configured to transmit signals to and receive signals from external device 50 via one or more antennas. For example, communication interface 56 may include a Wi-Fi transceiver for communication via a wireless communication network or a cellular or mobile phone communication transceiver. In another example, communication interface 56 may include a short-range wireless transmitter (e.g., a Bluetooth wireless transmitter, etc.) for communication via a short-range wireless communication transceiver.

[0087] The external device may be an external handheld device 50 operatively connected to the device 10, such as a mobile phone (e.g., a smartphone) or a tablet computer. Furthermore, the handheld device 50 preferably includes appropriate hardware and software capabilities to establish a wireless communication link with the device 10 and to send and receive signals to and from the device 10. Additionally, the external device may include suitable software applications configured to output a graphical user interface (GUI) including a graphical representation of a leak in the wound treatment system 1 via a display device of the external device 50.

[0088] Figure 6This is a schematic flowchart illustrating a computer-implemented method S100 for operating a device for providing negative pressure to a wound site, according to some embodiments. The device can be any of the embodiments disclosed herein. Therefore, the device may include: a negative pressure source configured to provide negative pressure to the wound site from an inlet of the negative pressure source via a first fluid flow path; an electronically controllable valve configured to release negative pressure from the wound site via a second fluid flow path; and a pressure sensor configured to measure the pressure level in the first or second fluid flow path. Furthermore, the device may be capable of operating to regulate the negative pressure provided to the wound site within multiple pressure regulation cycles, each pressure regulation cycle including a pressure regulation period and an irrigation period. Method S100 is preferably a computer-implemented method S100 executed by the processing system of the device. The processing system may include, for example, one or more processors and one or more memories coupled to one or more processors, wherein one or more memories store one or more programs that, when executed by one or more processors, cause the device to perform steps, services, and functions of any of the embodiments of the method S100 disclosed herein.

[0089] In some embodiments, method S100 includes depressurizing the wound site by activating a negative pressure source S101. In other words, method S100 may include turning on a negative pressure source to reduce the pressure level at the wound site from the ambient pressure level (i.e., as output by a pressure sensor) via a first fluid flow path. The negative pressure source S101 may be activated S101 until a set pressure value (e.g., -125 mmHg) has been reached (as indicated by one or more pressure sensors). Depressurization S101 should be interpreted as a process that is typically performed only during the initial startup of the device.

[0090] Furthermore, method S100 includes maintaining the pressure level output by the pressure sensor between an upper pressure value and a lower pressure value during the pressure regulation period by activating and deactivating the negative pressure source. The upper pressure value and the lower pressure value can be predefined in the device or otherwise preconfigured. As mentioned above, the upper pressure value can be, for example, -115 mmHg or -120 mmHg, while the lower pressure value can be, for example, -135 mmHg or -130 mmHg.

[0091] Then, once the flushing conditions are met, such as once sufficient time has elapsed since the last flushing period, the device enters the flushing period. Therefore, method S100 includes: during the flushing period, activating the negative pressure source S103 until a first pressure value (as output by a pressure sensor) is reached, and in response to reaching the first pressure value (as output by a pressure sensor), opening the electronically controllable valve S104. Once the first pressure value is reached, the negative pressure source can be deactivated or shut off. However, as mentioned above, there may be some overlap between opening the valve S104 and operating the negative pressure source, such that the negative pressure source may be deactivated after opening the valve S104. Furthermore, method S100 includes: during the flushing period, in response to reaching a second pressure value (as output by a pressure sensor) higher than the first pressure value, closing the electronically controllable valve S105, and activating the negative pressure source S107 until a target pressure value output by a pressure sensor is reached, wherein the target pressure value is a pressure value within a closed interval defined by an upper pressure value and a lower pressure value. In addition, in some embodiments, method S100 includes activating negative pressure source S107 before closing electronically controllable valve S105 until the target pressure value output by pressure sensor is reached.

[0092] Furthermore, in some embodiments, method S100 includes calculating a target pressure value in S106. This calculation can be performed at any suitable time point during the irrigation period, based on, for example, the formulas / equations discussed earlier. Therefore, in some embodiments, the target pressure value is set based on the pressure level (e.g., average pressure level) at the wound site over time during a previous time period. The time period may include one or more previous pressure regulation periods or one or more previous pressure regulation cycles (as discussed above).

[0093] Furthermore, in some embodiments, method S100 includes activating at least one LED among one or more LEDs included in the device in response to the negative pressure source being activated more than a first number during the pressure regulation period. Additionally, in some embodiments, method S100 includes sending a signal to an external device 50 via the device's communication interface in response to the negative pressure source 14 being activated more than a first number during the pressure regulation period.

[0094] Executable instructions for performing these functions may optionally be included in other computer program products or non-transitory computer-readable storage media configured for execution by one or more processors of a device for providing pressure relief to wound dressings.

[0095] The techniques disclosed herein have been presented above with reference to specific embodiments. However, other embodiments besides those described above are also possible and within the scope of the claims. Within the scope of the claims, method steps different from those described above for performing the method by hardware or software may be provided. Thus, according to some embodiments, a non-transitory computer-readable storage medium is provided storing one or more programs configured to be executed by one or more processors of a device for a decompression wound treatment system, said one or more programs including instructions for performing method S100 according to any of the embodiments described above. According to some embodiments, a computer program product is provided comprising instructions that, when executed by a computing device of a device for providing negative pressure to a wound site, cause the device to perform method S100 according to any of the embodiments described above.

[0096] Generally, computer-accessible media can include any tangible or non-transitory storage medium or storage medium, such as electronic, magnetic, or optical media coupled to a computer system via a bus. As used herein, the terms “tangible” and “non-transitory” are intended to describe computer-readable storage media (or “memory”) excluding those that propagate electromagnetic signals, but are not intended to otherwise limit the types of physical computer-readable storage devices covered by the phrases “computer-readable medium” or “memory.” For example, the terms “non-transitory computer-readable medium” or “tangible memory” are intended to cover types of storage devices that do not necessarily permanently store information, including, for example, random access memory (RAM). Program instructions and data stored on tangible computer-accessible storage media in non-transitory form can also be transmitted via transmission media or signals (e.g., electrical signals, electromagnetic signals, or digital signals), which can be transmitted via communication media such as networks and / or wireless links.

[0097] Processor 11 (associated with device 10) may be or include any number of hardware components for performing data or signal processing or for executing computer code stored in memory. Therefore, device 10 may have associated memory, and memory may be one or more devices for storing data and / or computer code for performing or facilitating the implementation of the various methods described herein. Memory may include volatile or non-volatile memory. Memory may include database components, object code components, script components, or any other type of information structure for supporting the various activities of this specification. According to some embodiments, any distributed or local memory device may be used with the systems and methods of this specification. According to some embodiments, memory (e.g., via circuitry or any other wired, wireless, or network connection) may be communicatively connected to processor 11 and includes computer code for performing one or more of the processes described herein.

[0098] It should be noted that any reference numerals in the drawings do not limit the scope of the claims, some embodiments can be implemented at least in part by means of both hardware and software, and several “apparatus” or “units” can be represented by the same piece of hardware.

[0099] Although the accompanying drawings may show a specific order of method steps, the order of steps may differ from the depicted order. Furthermore, two or more steps may be performed simultaneously or partially simultaneously. Such variations will depend on the chosen software and hardware system and the designer's choices. All such variations are within the scope of the appended claims. Similarly, software implementations can be achieved using rule-based logic and other logic through standard programming techniques to perform steps such as generation, activation, operation, and initiation. The embodiments mentioned and described above are given by way of example only and should not limit the appended claims. Other solutions, uses, purposes, and functions within the scope of the patent claims described below should be apparent to those skilled in the art.

Claims

1. A device (10) for providing negative pressure to a wound site, the device (10) comprising: A negative pressure source (14) is configured to provide negative pressure to the wound site from the inlet of the negative pressure source via a first fluid flow path; An electronically controllable valve (40) is configured to release negative pressure from the wound site via a second fluid flow path; Pressure sensors (15a, 15b) are configured to measure the pressure level in the first fluid flow path or the second fluid flow path; A control circuit system (11) is operatively connected to the negative pressure source, the electronically controllable valve, and the pressure sensor, wherein the control circuit system is configured to operate in multiple pressure regulation cycles (T... CYC The negative pressure provided to the wound site is adjusted, and each pressure adjustment cycle includes a pressure adjustment period and a flushing period; The control circuit system (11) is further configured to: During the pressure regulation period: By activating and deactivating the negative pressure source (14), the pressure level output by the pressure sensors (15a, 15b) is maintained between the upper and lower pressure values; During the rinsing period: Start the negative pressure source (14) until the first pressure value (202) is reached; In response to reaching the first pressure value, the electronically controllable valve (40) is opened. In response to reaching a second pressure value (203) higher than the first pressure value (201), the electronically controllable valve (40) is closed. The negative pressure source (14) is activated until the target pressure value (204) is reached, wherein the target pressure value is the pressure value within a closed interval defined by the upper pressure value and the lower pressure value.

2. The apparatus (10) according to claim 1, wherein, The target pressure value (204) is set based on the pressure level that changes over time as measured by the pressure sensors (15a, 15b) during a previous time period.

3. The apparatus (10) according to claim 1, wherein, The target pressure value (204) is set based on the average pressure level measured by the pressure sensor during a previous time period.

4. The apparatus (10) according to claim 2 or 3, wherein, The time period includes the previous pressure regulation period.

5. The apparatus (10) according to claim 2 or 3, wherein, The time period includes at least one previous pressure regulation cycle.

6. The apparatus (10) according to claim 2 or 3, wherein, The time period extends from the initial evacuation after the initial start-up of the device until the negative pressure source (14) is activated during the flushing period to reach the first pressure value (202).

7. The apparatus (10) according to any one of claims 1 to 6, wherein, During the flushing mode, the negative pressure source (14) is activated until the target pressure value (204) is reached before the electronically controllable valve (40) is closed.

8. The apparatus (10) according to any one of claims 1 to 7, further comprising: A canister (16) for collecting fluid from the wound site, wherein the canister forms part of the first fluid flow path between the negative pressure source (14) and the wound site.

9. The apparatus (10) according to any one of claims 1 to 8, wherein, The device (10) also includes a user interface (60) which includes one or more light-emitting diodes (LEDs) (62). The control circuit system (11) is operatively connected to the user interface and is further configured to: In response to the negative pressure source (14) being activated more than a first number of times during the pressure regulation period: Turn on at least one of the one or more LEDs (62).

10. A computer-implemented method (S100) for operating a device to provide negative pressure to a wound site, wherein, The device includes a negative pressure source, an electronically controllable valve, and a pressure sensor. The negative pressure source is configured to provide negative pressure to a wound site from its inlet via a first fluid flow path. The electronically controllable valve is configured to release negative pressure from the wound site via a second fluid flow path. The pressure sensor is configured to measure the pressure level in either the first or second fluid flow path. The device is operable in multiple pressure regulation cycles (T... CYC The method includes adjusting the negative pressure supplied to the wound site, with each pressure adjustment cycle comprising a pressure adjustment period and an irrigation period. During the pressure regulation period: By activating and deactivating the negative pressure source, the pressure level output by the pressure sensor is maintained (S102) between the upper pressure value and the lower pressure value; During the rinsing period: Start the negative pressure source (S103) until the first pressure value (202) is reached; In response to reaching the first pressure value (202), the electronically controllable valve is opened (S104); In response to reaching a second pressure value higher than the first pressure value (203), the electronically controllable valve is closed (S105); The negative pressure source is activated (S107) until the target pressure value (204) is reached, wherein the target pressure value is the pressure value within a closed interval defined by the upper pressure value and the lower pressure value.

11. The method according to claim 10 (S100), wherein, The target pressure value (204) is set based on the pressure level that changes over time as output by the pressure sensor during a previous time period.

12. The method according to claim 10 (S100), wherein, The target pressure value (204) is set based on the average pressure level output by the pressure sensor during the previous time period.

13. The method according to claim 11 or 12 (S100), wherein, The time period includes the previous pressure regulation period.

14. A computer program product comprising instructions that, when executed by a computing device of a means for providing negative pressure to a wound site, cause the means to perform the method (S100) according to any one of claims 10 to 13.

15. A system (1), comprising: The apparatus (10) according to any one of claims 1 to 9; Wound covering (22) for creating a sealed space partially defined by the wound site; as well as A piping assembly that defines a first fluid flow path and a second fluid flow path.

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