Wound treatment system with internal alternating orifices

Abstract

The present invention provides a wound treatment system, which includes: a dressing that can be sealed on a wound and defines a wound space between the dressing and the wound; a tube that can be fluidly connected to the wound space; and a tank that can be fluidly connected to the tube. The tank, the tube and the dressing define a sealed space including the wound space. The wound treatment system also includes a treatment unit connected to the tank. The treatment unit includes: a sensor configured to measure the pressure in the sealed space; a valve that is positioned between the sealed space and the surrounding environment and can be controlled between an open position and a closed position; and a control circuit. The control circuit is configured to control the valve to alternate between the open position and the closed position to allow airflow through the valve, receive a measurement result from the sensor, and determine the volume of the wound space based on the measurement result.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to U.S. Provisional Application No. 62 / 802,034, filed on February 6, 2019, which is incorporated herein by reference in its entirety. Background Art

[0003] The present disclosure generally relates to a wound treatment system, and more specifically to a wound treatment system that provides negative pressure wound therapy (NPWT). NPWT refers to the generation of negative pressure (relative to atmospheric pressure) at the wound site to promote wound healing. In a wound treatment system configured to provide NPWT, a dressing is typically sealed to a wound bed and is placed in fluid communication with a pump that is operable to draw negative pressure at the wound bed (i.e., in the wound space between the wound bed and the dressing). Because the dressing is sealed to the wound bed, typically for a period of several days, it may be difficult to detect and monitor the progress of wound healing. One way to determine the amount of wound healing is based on the change in the amount of volume between the wound bed and the dressing (i.e., when the wound heals into the volume to occupy / consume a portion of the volume). Therefore, systems and methods for volume determination in wound treatment systems may be advantageous.

[0004] In some cases, NPWT may be provided in conjunction with drip therapy and described as negative pressure and instillation wound therapy (NPIWT). Drip therapy refers to providing a drip fluid (e.g., saline, antibiotic fluid) to a wound. One challenge in drip therapy can be determining how much fluid to provide to a wound. It may be preferred to determine the amount of fluid to be provided based on the size of the wound and / or the volume of available space adjacent to the wound (i.e., between the dressing and the wound). Therefore, systems and methods for volume determination in a wound treatment system can be beneficial for drip therapy. Summary of the invention

[0005] One embodiment of the present disclosure is a wound treatment system. The wound treatment system includes: a dressing, which can be sealed on a wound and define a wound space between the dressing and the wound; a tube, which is connected to the dressing and can be fluidly communicated with the wound space; and a tank, which can be fluidly communicated with the tube. The tank, the tube and the dressing define a sealed space including the wound space. A treatment unit is connected to the tank. The treatment unit includes: a pneumatic pump, which can be fluidly communicated with the sealed space; a sensor, which is configured to measure the pressure in the sealed space; a valve, which is positioned between the sealed space and the surrounding environment and can be controlled between an open position and a closed position; and a control circuit. The control circuit is configured to control the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space, control the valve to repeatedly alternate between the open position and the closed position to achieve a controlled airflow rate through the valve, receive a measurement of the pressure in the sealed space from the sensor, and determine the volume of the wound space based on the measurement of the pressure.

[0006] In some embodiments, the controlled gas flow rate is less than a restrictive rate of a filter positioned between the valve and the canister.

[0007] In some embodiments, the valve comprises a solenoid valve. The control circuit is configured to control the valve by providing a voltage pattern to the solenoid valve to repeatedly alternate between the open position and the closed position. The voltage pattern comprises a step function that repeatedly steps between approximately zero voltage and a non-zero voltage. The voltage pattern is capable of maintaining a maximum continuous duration of no more than approximately 500 milliseconds at the non-zero voltage.

[0008] In some embodiments, the voltage pattern includes a repeating pattern of about 400 milliseconds at a non-zero voltage, about 100 milliseconds at about zero voltage, about 400 milliseconds at a non-zero voltage, and about 100 milliseconds at about zero voltage. The voltage pattern may include a first set of two cycles of the repeating pattern, about one second at about zero voltage, and a second set of two cycles of the repeating pattern. The voltage pattern may cause the solenoid valve to alternate between the open position and the closed position with a period of about 500 milliseconds.

[0009] In some embodiments, the control circuit is further configured to customize a customized wound therapy based on the volume of the wound space and control the therapy unit to provide the customized wound therapy.The customized wound therapy can include an instillation therapy.

[0010] In some embodiments, the control circuit is configured to customize the instillation therapy by determining an amount of instillation fluid supplied to the wound space based on the volume of the wound space. The wound therapy system may include: a drip tube coupled to the dressing and fluidly communicable with the wound space; a drip fluid source fluidly communicable with the drip tube; and a drip pump controllable by the control circuit to provide the amount of the instillation fluid from the source to the wound space.

[0011] Another embodiment of the present disclosure is a method for treating a wound. The method includes establishing a sealed space defined by a dressing, a tube, and a canister of a wound treatment system. The sealed space includes a wound space defined by the dressing and the wound. The method includes removing air from the sealed space with a pneumatic pump to establish a negative pressure in the sealed space, and alternating a solenoid valve between an open position and a closed position. The solenoid valve allows airflow from the surrounding environment to flow into the sealed space in the open position, and prevents the airflow from the surrounding environment from flowing into the sealed space in the closed position. The method also includes measuring the pressure in the sealed space to generate a pressure measurement result, determining the volume of the wound space based on the pressure measurement result, customizing a customized wound treatment based on the volume of the wound space, and providing the customized wound treatment to the wound.

[0012] In some embodiments, customizing the customized wound therapy includes determining an amount of instillation fluid to be supplied to the wound space based on the volume of the wound space. Providing the customized wound therapy to the wound includes controlling an instillation pump to supply the amount of the instillation fluid to the wound space.

[0013] In some embodiments, alternating the solenoid valve between the open position and the closed position provides a controlled airflow rate from the ambient environment to the sealed space. The controlled airflow rate is less than a restriction rate of a filter positioned between the canister and the solenoid valve.

[0014] In some embodiments, alternating the solenoid valve between the open position and the closed position includes providing a voltage pattern to the solenoid valve. The voltage pattern may include a step function that repeatedly steps between approximately zero voltage and a non-zero voltage. The voltage pattern may include a repeating pattern of approximately 400 milliseconds at a non-zero voltage, approximately 100 milliseconds at approximately zero voltage, approximately 400 milliseconds at a non-zero voltage, and approximately 100 milliseconds at approximately zero voltage.

[0015] In some embodiments, the voltage pattern includes a first group of two cycles of the repeating pattern, about one second at about zero voltage, and a second group of two cycles of the repeating pattern. The non-zero voltage can cause the solenoid valve to be in the open position. During every 400 milliseconds at the non-zero voltage, a positive pressure of about 5 mmHg is provided to the sealed space.

[0016] Another embodiment of the present disclosure is a wound treatment system. The wound treatment system includes a dressing, which can be sealed on a wound and define a wound space between the dressing and the wound; a first tube, which is connected to the dressing and can be fluidly connected to the wound space; a tank, which can be fluidly connected to the first tube, wherein the tank, the first tube and the dressing define a sealed space including the wound space; a pneumatic pump, which can be fluidly connected to the sealed space; a sensor, which is configured to measure the pressure in the sealed space; and a solenoid valve, which can be controlled between an open position and a closed position. The solenoid valve is configured to allow air to flow from the surrounding environment to the sealed space in the open position, and prevent air from flowing from the surrounding environment to the sealed space in the closed position. The wound treatment system also includes a drip tube, which is connected to the dressing and can be fluidly connected to the wound space and a source of drip fluid; a drip pump, which is connected to the drip tube and can be controlled to supply an amount of drip fluid to the wound space; and a control circuit. The control circuit is configured to control the pneumatic pump to remove air from the sealed space, thereby establishing a negative pressure in the sealed space and provide a voltage pattern to the solenoid valve. The voltage pattern causes the solenoid valve to repeatedly alternate between the open position and the closed position. The control circuit is also configured to receive a measurement of the pressure from the sensor, determine a volume of the wound space based on the measurement of the pressure, determine the amount of the instillation fluid based on the volume of the wound space, and control the instillation pump to supply the amount of the instillation fluid to the wound space.

[0017] In some embodiments, alternating the solenoid valve between the open position and the closed position enables a controlled air flow rate from the ambient environment to the sealed space through the solenoid valve.

[0018] In some embodiments, the solenoid valve is positioned to allow the air to enter one or more outer lumens of the first tube. In some embodiments, a filter is positioned between the solenoid valve and the one or more outer lumens. The solenoid valve is alternated between the open position and the closed position to achieve a controlled airflow rate from the ambient environment to the passage through the solenoid valve, and the controlled rate is less than a limiting rate of the filter.

[0019] In some embodiments, the infusion pump, the pneumatic pump, and the control circuit are housed within a treatment unit. In some embodiments, the solenoid valve is positioned within the treatment unit. In some embodiments, the solenoid valve is positioned outside the treatment unit and is coupled to the first tube.

[0020] Another embodiment of the present disclosure is a treatment unit. The treatment unit includes: a pneumatic pump that can be fluidly connected to a sealed space; a sensor that is configured to measure the pressure in the sealed space; a valve that is positioned between the sealed space and the surrounding environment and can be controlled between an open position and a closed position; and a control circuit. The control circuit is configured to control the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space, control the valve to repeatedly alternate between the open position and the closed position to achieve a controlled airflow rate through the valve, receive a measurement of the pressure in the sealed space from the sensor, and determine the volume of the sealed space based on the measurement of the pressure and the controlled rate, and provide customized wound treatment based on the volume of the sealed space.

[0021] In some embodiments, the control circuit is configured to achieve the controlled air flow rate through the valve by controlling the valve to the open position for a maximum continuous duration of no more than about 500 milliseconds.

[0022] Another embodiment of the present disclosure is a wound treatment system. The wound treatment system includes: a pneumatic pump that can be fluidly connected to a canister; and a tube that includes a first lumen and a second lumen. The first lumen is configured to facilitate the flow of fluid from a dressing to the canister, and the second lumen is configured to facilitate the measurement of pressure at the dressing. The wound treatment system also includes: a sensor that is configured to measure the pressure in the second lumen; a valve that is positioned between the second lumen and the surrounding environment and can be controlled between an open position and a closed position; a filter that is positioned between the valve and the second lumen; and a cover that can be removably coupled to the tube. When the cover is coupled to the tube, the cover provides fluid communication between the first lumen and the second lumen. The wound treatment system also includes a control circuit that is configured to operate the pump to remove air from the canister, control the valve to an open position, receive a measurement of the pressure in the second lumen from the sensor, and determine a flow rate through the filter based on the measurement of the pressure in the second lumen when the cover is coupled to the tube.

[0023] In some embodiments, the control circuit is configured to determine a volume of a wound space based on the flow rate through the filter and additional measurements of the pressure from the sensor when the cover is removed from the tube and the dressing is coupled to the tube. In some embodiments, the control circuit is configured to provide customized wound therapy based on the volume of the wound space. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various objects, aspects, features and advantages of the present disclosure will become more apparent and better understood by reference to the detailed description taken in conjunction with the accompanying drawings, in which like reference numerals identify corresponding elements throughout. In the accompanying drawings, like reference numerals generally indicate identical, functionally similar and / or structurally similar elements.

[0025] Figure 1 is a partial block diagram of a negative pressure wound therapy system including a therapy device coupled to a wound dressing via tubing according to an exemplary embodiment.

[0026] Figure 2 is a more detailed illustration of the exemplary embodiment according to Figure 1 Block diagram of a negative pressure wound therapy system.

[0027] Figure 3 is a more detailed illustration of the exemplary embodiment according to Figure 1 Block diagram of the negative pressure circuit, fluid removal tank circuit, and wound site circuit of a negative pressure wound therapy system.

[0028] Figure 4is a block diagram illustrating a negative pressure wound therapy system according to an exemplary embodiment.

[0029] Figure 5 is a flow chart of a method of using a negative pressure wound therapy system according to an exemplary embodiment.

[0030] Fig. 6A is a flow chart of a method of instilling an initial amount of fluid into a wound site using a negative pressure wound therapy system according to an exemplary embodiment.

[0031] Figure 6B Illustrated is a negative pressure wound therapy system applied to a desired wound site to be treated prior to instilling an initial fluid volume into the wound site according to an exemplary embodiment.

[0032] Figure 6C Illustrated is a diagram of a negative pressure wound therapy system after applying a first negative pressure according to an exemplary embodiment. Figure 6B Negative pressure wound therapy system.

[0033] Fig.6D According to an exemplary embodiment, the Figure 6C After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Figure 6C Negative pressure wound therapy system.

[0034] Fig. 6E Illustrated is a diagram of a method of applying a second negative pressure to a negative pressure wound therapy system according to an exemplary embodiment. Figure 6B Negative pressure wound therapy system.

[0035] Fig. 6F According to an exemplary embodiment, the Fig. 6E After applying the second negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Fig. 6E Negative pressure wound therapy system.

[0036] Figure 6G The use of the exemplary embodiment is illustrated Figure 6B The wound treatment system drips fluid into the wound site.

[0037] Figure 7 A negative pressure wound therapy system is illustrated being applied to a wound site after an initial instillation of a fluid into the wound site according to an exemplary embodiment.

[0038] Fig. 8A is used according to an exemplary embodiment Figure 7 Flow chart of a method for a negative pressure wound therapy system to instill an additional amount of fluid into a wound site.

[0039] Figure 8BIllustrated is a diagram of a negative pressure wound therapy system after applying a first negative pressure according to an exemplary embodiment. Figure 7 Negative pressure wound therapy system.

[0040] Figure 8C According to an exemplary embodiment, the Figure 8B After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Figure 8B Negative pressure wound therapy system.

[0041] Fig.8D Illustrated is a diagram of a method of applying a second negative pressure to a negative pressure wound therapy system according to an exemplary embodiment. Figure 7 Negative pressure wound therapy system.

[0042] Fig. 8E According to an exemplary embodiment, the Fig.8D After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Fig.8D Negative pressure wound therapy system.

[0043] Fig.9A is used according to an exemplary embodiment Figure 7 Flow chart of a method for a negative pressure wound therapy system to instill an additional amount of fluid into a wound site.

[0044] Fig. 9B Illustrated is a diagram of a negative pressure wound therapy system after applying a first negative pressure according to an exemplary embodiment. Figure 7 Negative pressure wound therapy system.

[0045] Fig. 9C According to an exemplary embodiment, the Fig. 9B After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Fig. 9B Negative pressure wound therapy system.

[0046] Fig.9D Illustrated is a diagram of a method of applying a second negative pressure to a negative pressure wound therapy system according to an exemplary embodiment. Figure 7 Negative pressure wound therapy system.

[0047] Fig.9E According to an exemplary embodiment, the Fig.9D After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Fig.9D Negative pressure wound therapy system.

[0048] Fig. 10A is a flow chart of a method of determining whether sufficient dead space exists in a negative pressure wound therapy system according to an exemplary embodiment.

[0049] Fig. 10B Illustrated is a diagram of a negative pressure wound therapy system after applying a first negative pressure according to an exemplary embodiment. Figure 7 Negative pressure wound therapy system.

[0050] Fig. 10C According to an exemplary embodiment, the Fig. 10B After applying the first negative pressure as shown in FIG. , during exhaust of the negative pressure wound therapy system Fig. 10B Negative pressure wound therapy system.

[0051] Fig.11 is a flow chart of a process for monitoring the healing progress of a wound site over time according to an exemplary embodiment.

[0052] Fig.12 is a flow chart of a method of instilling an initial amount of fluid into a wound site using a negative pressure wound therapy system according to an exemplary embodiment.

[0053] Fig.13 A negative pressure wound therapy system including a tube set module according to an exemplary embodiment is illustrated.

[0054] Fig.14 A negative pressure wound therapy system including a tube set module according to an exemplary embodiment is illustrated.

[0055] Fig.15 A negative pressure wound therapy system including a tube set module according to an exemplary embodiment is illustrated.

[0056] Fig.16A is a block diagram of a negative pressure wound therapy system including a tube set module according to an exemplary embodiment.

[0057] Fig. 16B The invention illustrates a method according to an exemplary embodiment including Fig.16A Negative pressure wound therapy system with tube set module.

[0058] Fig.17 is a flow chart of a fully automated method of operating a tube bank module according to an exemplary embodiment.

[0059] Fig.18 is a block diagram of a negative pressure and instillation wound therapy (NPIWT) system according to an exemplary embodiment.

[0060] Fig.19 is in a closed position according to an exemplary embodiment Fig.18 Cross-sectional view of the solenoid valve of the NPIWT system.

[0061] Fig. 20 is in an open position according to an exemplary embodiment Fig.19 Cross-sectional view of a solenoid valve.

[0062] Fig.21 According to an exemplary embodiment Fig.18 Cross-sectional view of the tubes of the NPIWT system.

[0063] Fig. 22 According to an exemplary embodiment, a method for using Figures 19 to 20 Solenoid valve management Fig.21 Flow chart of the method of tube plugging.

[0064] Fig.23 is a method for generating a Fig.18 Flow chart of the method of volume determination performed by the NPIWT system.

[0065] Fig.24 is an example of an exemplary embodiment Fig.23 A collection of graphs showing various aspects of the method.

[0066] Fig.25 A removable cover according to an exemplary embodiment Fig.18 Block diagram of the NPIWT system. DETAILED DESCRIPTION

[0067] Overview

[0068] See also Figures 1 to 17 , shows a wound treatment system according to various exemplary embodiments. The wound treatment system may include a treatment device and a wound dressing. The treatment device may include an instillation fluid tank, a removal fluid tank, a valve, a pneumatic pump, an instillation pump, a tube set module and a controller. The wound dressing may be applied to the skin around the wound of the patient. The treatment device may be configured to deliver the instillation fluid to the wound and provide negative pressure wound therapy (NPWT) by maintaining the wound under negative pressure. The components of the wound treatment device, the wound dressing and the wound site form a negative pressure loop.

[0069] The controller can be configured to operate the pneumatic pump, the instillation pump, the tube set module, and / or other controllable components of the treatment device. In some embodiments, the controller estimates the wound volume based on a comparison of the observed dynamic pressure response of the negative pressure applied to the entire negative pressure circuit and the negative pressure applied to the selected portion of the negative pressure circuit. Based on the comparison of the observed dynamic response, the controller can be configured to determine the amount of instillation fluid to be delivered to the wound site.

[0070] The tube set module includes one or more elements that can be actuatable, controllable or otherwise engaged by a controller, wherein selective communication between the controller and the tube set module is configured to allow the controller to implement and monitor various dynamic pressure responses in all and / or part of the negative pressure circuit as needed to, among other functions, estimate wound volume, determine the amount of instillation fluid to be delivered to the wound site, and / or perform any other number of functions that may be associated with the use of the NPWT system 100.

[0071] According to some embodiments, the volume relative to the wound site determined by the controller may be related to the dead space at the wound site (i.e., the available space surrounding the wound site within the applied drape layer into which the instillation fluid can be delivered). In some such embodiments, the controller may be configured to determine the amount of instillation fluid to be delivered to the wound site based on a predetermined percentage (e.g., 20%, 50%, 80%, etc.) of the calculated dead space volume at the wound site. The controller may then operate the tube set module and the instillation pump to deliver the determined instillation fluid volume to the wound. By basing the amount of instillation fluid to be delivered to the wound site on the calculated dead space volume at the wound site, the negative pressure system may be configured to provide more efficient and more accurate delivery of the instillation fluid, which may reduce the risk of leakage caused by over-delivery of the instillation fluid and the risk of ineffective treatment of the wound site caused by insufficient delivery of the instillation fluid.

[0072] In some embodiments, during wound treatment, the controller may additionally or alternatively measure and monitor a volume relative to the wound site multiple times, wherein the controller determines the progress of healing at the wound site based on changes in the measured volume relative to the wound site during NPWT treatment. By monitoring the progress of healing at the wound site, the controller may be configured to alert a user if healing at the wound site is not proceeding as expected or desired. These and other features of the wound treatment system are described in detail below.

[0073] Wound therapy system

[0074] See now Figure 1 , a negative pressure wound therapy (NPWT) system 100 is shown according to an exemplary embodiment. The NPWT system 100 is shown to include a treatment device 102 fluidly connected to a wound dressing 112 via tubes 108 and 110. As will be described in more detail below, according to various embodiments, a tube set module 300 can be operably connected to tubes 108 and / or 110.

[0075] According to various embodiments, a wound dressing 112 may be placed over or within a wound site 114 and adhered or sealed to the patient's skin 116 surrounding the wound site 114 using a drape layer 117. Several examples of wound dressings 112 that may be used in combination with the NPWT system 100 are also described in detail in U.S. Patent No. 7,651,484, issued on January 26, 2010, U.S. Patent No. 8,394,081, issued on March 12, 2013, and U.S. Patent Application No. 14 / 087,418, filed on November 22, 2013. The entire disclosure of each of these patents and patent applications is incorporated herein by reference.

[0076] like Figure 2 , in general, the treatment device 102 includes a pneumatic pump 120, an infusion pump 122, a filter 128, and a controller 118. The pneumatic pump 120 may be fluidically coupled to the removal fluid tank 106 (e.g., via a conduit 136), and may be configured to evacuate the removal fluid tank 106 by pumping air out of the removal fluid tank 106. In some embodiments, the pneumatic pump 120 is configured to operate in both a forward direction and a reverse direction. For example, the pneumatic pump 120 may operate in a forward direction to pump air out of the removal fluid tank 106 and reduce the pressure in the removal fluid tank 106. The pneumatic pump 120 may operate in a reverse direction to pump air into the removal fluid tank 106 and increase the pressure in the removal fluid tank 106. The pneumatic pump 120 may be controlled by the controller 118, which will be described in more detail below.

[0077] The treatment device 102 can be configured to provide negative pressure wound therapy by reducing the pressure at the wound site 114. The treatment device 102 can be vacuumed (relative to atmospheric pressure) at the wound site 114 by removing wound exudate, air and other fluids from the wound site 114. The wound exudate may include a fluid filtered from the patient's circulatory system to the lesion or inflammation area. For example, the wound exudate may include water and dissolved solutes, such as blood, plasma proteins, white blood cells, platelets and red blood cells. Other fluids 121 removed from the wound site 114 may include a drip fluid 105 previously delivered to the wound site 114. The drip fluid 105 may include, for example, a cleaning fluid, a prescription fluid, a drug-carrying fluid, an antibiotic fluid, or any other type of fluid that may be delivered to the wound site 114 during wound treatment. The drip fluid 105 may be maintained in the drip fluid tank 104 and controllably distributed to the wound site 114 via the tube 108. In some embodiments, the infusion fluid tank 104 is detachable from the therapeutic device 102 to allow for refilling and replacement of the infusion fluid tank 106 as needed.

[0078] The drip pump 122 may be fluidly coupled to the drip fluid tank 104 via the upstream drip tube 108a and to the wound dressing 112 via the downstream drip tube 108b. The drip pump 122 may be operated to deliver the drip fluid 105 to the wound dressing 112 and the wound site 114 by pumping the drip fluid 105 through the upstream drip tube 108a and the downstream drip tube 108b. The drip pump 122 may be controlled by the controller 118, which will be described in more detail below. According to some embodiments, the drip tube valve 109 is configured to allow flow only in the direction from the drip fluid tank 104 to the wound site 114 (e.g., via a one-way valve, or via a valve configured to be selectively switched to a closed position by a user and / or the controller 118 before applying negative pressure to the wound site 114), which drip tube valve may generally be disposed at a position along a portion of the downstream drip tube 108b. As will be described in greater detail below, according to various embodiments, a drip tube valve 109 may be provided as part of a tubing set module 300 .

[0079] The filter 128 may be positioned between the removal fluid tank 106 and the pneumatic pump 120 (e.g., along the conduit 136) such that air pumped from the removal fluid tank 106 passes through the filter 128. The filter 128 may be configured to prevent liquid or solid particles from entering the conduit 136 and reaching the pneumatic pump 120. The filter 128 may include, for example, a hydrophobic and / or lipophilic bacterial filter such that aqueous liquids and / or oily liquids will bead up on the surface of the filter 128. The pneumatic pump 120 may be configured to provide sufficient airflow through the filter 128 such that a pressure drop across the filter 128 is not significant (e.g., such that the pressure drop will not substantially impede the application of negative pressure from the treatment device 102 to the wound site 114).

[0080] The removal fluid tank 106 can be a component of the treatment device 102 that is configured to collect wound exudate and other fluids 121 removed from the wound site 114. In some embodiments, the removal fluid tank 106 can be detachable from the treatment device 102 to allow the removal fluid tank 106 to be emptied and replaced as needed. The lower portion of the removal fluid tank 106 can be filled with wound exudate and other fluids 107 removed from the wound site 114, while the upper portion of the removal fluid tank 106 can be filled with air. The treatment device 102 can be configured to draw a vacuum within the removal fluid tank 106 by pumping air out of the removal fluid tank 106. The reduced pressure within the removal fluid tank 106 can be transferred to the wound dressing 112 and the wound site 114 via the tube 110.

[0081] like Figure 1As shown in , a tube valve 111 is disposed along the tube 110 at a location between the removal fluid tank 106 and the wound site 114, and is configured to selectively permit and prevent fluid from flowing between the removal fluid tank 106 and the wound site 114. The tube valve 111 may be defined by any number of different structures (e.g., spring biased structures, duckbill structures, clamping structures, check valve structures, etc.) that are configured to allow fluid to be selectively controlled through the tube 110, and may include being configured to be selectively opened and / or closed by a user in response to a sensed stimulus (e.g., a predetermined threshold pressure) or by a controller 118. As will be described in more detail below, according to various embodiments, the tube valve 111 may be provided as part of the tube set module 300.

[0082] See also Figure 3 , when tube valve 111 is in an open flow configuration, removal fluid tank 106, tube 110 (i.e., both upstream tube portion 110a and downstream tube portion 110b), conduit 136 extending between pneumatic pump 120 and removal fluid tank 106, a portion of downstream drip tube 108b extending between drape layer 117 and drip tube valve 109, and wound site 114 are fluidly connected to define negative pressure circuit 200. See also Figure 3 , when tube valve 111 is in the closed, non-flow configuration, removal fluid tank 106, conduit 136, and upstream tube portion 110a of tube 110 extending between removal fluid tank 106 and tube valve 111 define a removal fluid tank circuit 202 that is fluidly isolated from a wound site circuit 204 defined by wound site 114, downstream tube portion 110b of tube 110 extending between tube valve 111, a portion of downstream drip tube 108b extending between drape layer 117 and drip tube valve 109, and wound site 114. As will be discussed in greater detail below, the volume of tube 110, the volume of conduit 136, and the volume of the portion of downstream drip tube 108b extending between drape layer 117 and drip tube valve 109 define a known volume that may be readily subtracted from or otherwise accounted for in a volume calculation relative to wound site 114.

[0083] See again Figure 1According to some embodiments, at a location upstream of the tube valve 111 and downstream of the removal fluid tank 106, a graduated leakage device 113 is additionally disposed along the tube 110 and operably fluidly connected to the tube, the graduated leakage device being defined by a vent hole 113a formed through the outer wall of the tube 110, the vent hole 113a being selectively closable by a vent valve 113b. Also forming part of the graduated leakage device 113 may be a flow detector 113c configured to measure the airflow through the vent hole 113a. As will be described in more detail below, the graduated leakage device 113 is configured to selectively control and measure the airflow between the tube 110 and the surrounding environment surrounding the treatment device 102. According to various embodiments, the graduated leakage device 113 may be selectively opened to allow airflow to enter the tube 110 at a known predetermined rate. As will be described in more detail below, according to various embodiments, the graduated leakage device 113 may be provided as part of the tube set module 300.

[0084] As will be described in more detail below, when both the exhaust valve 113b and the tube valve 111 are closed, the operation of the pneumatic pump 120 can be configured to evacuate only the removal fluid tank circuit 202 portion of the negative pressure circuit 200 (such as, for example, Fig. 6E When the exhaust valve 113b is closed and the tube valve 111 is opened, the operation of the pneumatic pump 120 can be configured to draw a vacuum in the entire negative pressure circuit 200 (such as, for example, Figure 6C When the vent valve 113b is open and the tube valve 111 is closed, airflow from the surroundings of the treatment device 102 can enter through the vent hole 113a of the graduated leak device 113 and fill the vacuum within the removal fluid tank circuit 202 (such as, for example Fig. 6F As exemplified). Fig.6D As shown, when both the exhaust valve 113b and the tube valve 111 are opened, the airflow from the surrounding environment of the treatment device 102 can enter through the exhaust hole 113a of the graduated leakage device 113 and fill the vacuum in the entire negative pressure circuit 200. It should be understood that according to various embodiments, the opening and / or closing of the exhaust valve 113b and / or the tube valve 111 can be achieved manually or automatically, for example, using the tube set module 300.

[0085] Although the disclosed graduated leakage device 113 is positioned in-line with the portion of the tube 110 extending between the wound site 114 and the removal fluid tank 106, according to some embodiments, such as for example Figure 4 As illustrated, the graduated leakage device 113 may also be formed in series with the conduit 136 . Figure 4 The operation of the graduated leakage device 113 of the embodiment is similar to Figure 1 The operation of the illustrated graduated leakage device 113, wherein Figure 4The graduated leakage device 113 is configured to provide a path through which air from the surrounding environment can flow into and fill part or all of the negative pressure circuit 200 after a vacuum is formed in part or all of the negative pressure circuit 200. It should be understood that according to various embodiments, the invention described herein may be combined with the invention. Figure 1 Any of the methods or systems of the illustrated graduated leakage device 113 embodiments may be used as Figure 4 The illustrated embodiment of the graduated leakage device 113 is modified.

[0086] like Figure 2 , according to various embodiments, the controller 118 can be configured to operate various components of the treatment device 102. Specifically, as will be described in more detail below, according to various embodiments, the controller 118 can be configured to control various components of the NPWT system 100 to perform one or more volume determination processes, via which, for example, the amount of instillation fluid 105 to be delivered to the wound site 114 can be determined, the healing progress of the wound site 114 can be tracked, etc. According to various embodiments, the controller 118 can be configured so that these processes can be performed with minimal user intervention and / or input.

[0087] According to various embodiments, the treatment device 102 may include a variety of sensors. For example, in some embodiments, the treatment device 102 may include pressure sensors 115a and / or 115b that are positioned inline in the upstream tube portion 110a and / or the downstream tube portion 110b and are configured to measure the pressure at the removal fluid tank 106 and / or the wound site 114. The pressure measurements recorded by the pressure sensors 115a and / or 115b may be transmitted to the controller 118. According to various embodiments, the controller 118 may use the pressure measurements from the pressure sensors 115a and / or 115b as input to various pressure testing operations and control operations performed by the controller 118. As will be described in more detail below, according to various embodiments, the pressure sensors 115a and / or 115b may be provided as part of the tube set module 300.

[0088] In some embodiments, the therapeutic device 102 includes a user interface 126. The user interface 126 may include one or more buttons, dials, slide bars, keys, or other input devices configured to receive input from a user. The user interface 126 may also include one or more display devices (e.g., LEDs, LCD displays, etc.), speakers, tactile feedback devices, or other output devices configured to provide information to the user. The user interface 126 may also display an alarm generated by the controller 118. For example, in the case where the removal of the fluid tank 106 is not detected, the controller 118 may generate a "no tank" alarm.

[0089] In some embodiments, the therapeutic device 102 includes a data communication interface 124 (e.g., a USB port, a wireless transceiver, etc.) configured to receive and transmit data. The communication interface 124 may include a wired or wireless communication interface (e.g., a jack, an antenna, a transmitter, a receiver, a transceiver, a line terminal, etc.) for communicating data with an external system or device. In various embodiments, the communication may be direct (e.g., local wired or wireless communication) or via a communication network (e.g., a WAN, the Internet, a cellular network, etc.). For example, the communication interface 124 may include a USB port or an Ethernet card and a port for sending and receiving data via an Ethernet-based communication link or network. In another example, the communication interface 124 may include a Wi-Fi transceiver or a cellular or mobile phone communication transceiver for communicating via a wireless communication network.

[0090] How to use

[0091] See also Figure 5 , a flow chart of a method 500 of using the NPWT system 100 according to an exemplary embodiment is shown. FIG. 6A to FIG. 6G As will be discussed in greater detail, initial setup of the NPWT system 100 and delivery of an initial amount of instillation fluid 105 to a wound site 114 being treated by the NPWT system 100 occurs at step 502 .

[0092] As shown at step 504, according to various embodiments, it may be desirable to deliver additional instillation fluid 105 to the wound site 114 after instilling an initial amount of instillation fluid 105 into the wound site 114. It should be understood that determining when and whether additional instillation fluid 105 is delivered to the wound site 114 at step 504 may be based on any number of various factors, including, for example, the elapsed time since the last instillation, the type of wound site 114, the course of treatment desired for the wound site 114, sensed conditions associated with the wound site 114, etc., and may be determined automatically by the controller 118, or may be based on user input.

[0093] If it is determined at step 504 that additional fluid is to be delivered, then at step 506, the dead space 119 at the wound site 114 is determined according to any of the methods described below. According to various embodiments (described in more detail below), at step 506, the controller 118 may be configured to determine the dead space 103 at the wound site 114 prior to delivery of such additional instillation fluid 105, regardless of whether the amount of instillation fluid 105 previously instilled into the wound site 114 is known; whether there is unabsorbed instillation fluid 105 and / or wound exudate in the space defined between the wound site 114 and the drape layer 117; whether the volume of any contents 107 in the removal fluid canister 106, the volume of the removal fluid canister 106 itself, and / or the volume of any contents 107 previously emptied from the removal fluid canister 106 is known; whether the removal fluid canister 106 has been replaced with a different sized removal fluid canister 106 during the NPWT treatment; changes in the shape / size / volume of the wound site 114; and the like.

[0094] At step 508, an amount of additional instillation fluid 105 to be delivered to the wound site 114 is calculated. According to various embodiments, the amount of additional instillation fluid 105 delivered to the wound site 114 may be based on the dead space volume determined at step 506. For example, in some embodiments, the controller 118 may calculate the volume of instillation fluid 105 to be delivered to the wound site 114 by multiplying the dead space volume determined at step 506 by a fluid instillation factor. The fluid instillation factor may be equal to or less than one (i.e., between zero and one) so that the volume of instillation fluid 105 delivered to the wound site 114 does not exceed the available space (i.e., the dead space) within the drape layer 117, thereby minimizing the risk of accidental leakage from the wound dressing 112 / drape layer 117. In some embodiments, the fluid instillation factor is between about 0.2 and about 0.8.

[0095] In addition to being used to calculate the volume of the instilled fluid 105, in some embodiments, the NPWT system 100 may additionally or alternatively be used to monitor and track the healing progress of the wound site 114 over time. Thus, in some embodiments, the method 500 may optionally include a step 510 of estimating the volume of the wound site 114 and using the estimated volume to track the healing progress of the wound site 114, as described below with reference to Fig.11 Discuss in more detail.

[0096] In some embodiments, it may be desirable to remove the instillation fluid 105 previously instilled into the wound site 114 from the wound site 114 at some time after the instillation fluid 105 is delivered to the wound site 114. Therefore, it may be advantageous to confirm that the dead space in the removal fluid tank 106 will be sufficient to accommodate the instillation fluid 105 removed from the wound site 114 and / or any additional fluid 121 (e.g., wound exudate) before instilling the instillation fluid 105 into the wound site 114, and then deliver the additional instillation fluid 105 to the wound site 114. Therefore, the method 500 may optionally include a step 512 at which the volume of the additional instillation fluid 105 calculated at step 508 is compared to the dead space of the removal fluid tank 106 (e.g., the dead space measured during the determination of the dead space at the wound site 114 at step 506), wherein if the instillation fluid 105 to be delivered exceeds the dead space of the removal fluid tank 106, an alert is issued to the user at step 514. If the instillation fluid 105 to be delivered does not exceed the dead space of the removal fluid tank 106 (or if step 512 is not included as part of method 500), the calculated instillation fluid 105 is delivered to the wound site 114, wherein some or all of steps 504, 506, 508, 510, 512, 514, 516 are repeated any number of additional times during the NPWT treatment.

[0097] See also Fig. 6A , shows a flow chart detailing the steps of a method 600 for initial setup of the NPWT system 100 and for delivering an initial amount of instillation fluid 105 to the Figure 5 The wound site 114 required in step 502 of the method 500 is provided. At step 602, a NPWT system 100 (such as, for example, Figure 1 exemplified), wherein the drape layer 117 and the wound dressing 112 are positioned at the desired wound site 114 to be treated, such as, for example Figure 6B shown.

[0098] Once the setup of the NPWT system 100 is completed at step 502, determining the dead space 119 available at the wound site 114 to which the instillation fluid 105 can be delivered can begin at step 604, where the controller 118 operates the pneumatic pump 120 to establish a first desired negative pressure within the entire negative pressure circuit 200, such as, for example Figure 6C exemplified.

[0099] In embodiments where the tube valve 111 comprises a normally closed pressure-sensitive valve that can be opened in response to an applied predetermined threshold negative pressure, the first desired negative pressure generated by the controller 118 at step 604 may be equal to or greater than the predetermined threshold pressure required to open the tube valve 111, so as to ensure that the vacuum applied by the pneumatic pump 120 is applied to the entire negative pressure circuit 200. In some embodiments, the threshold pressure required to open the tube valve 111 may be a pressure of approximately negative 125 mmHg, wherein the controller 118 is configured to apply a first negative pressure equal to or greater than negative 125 mmHg at step 604.

[0100] Alternatively, in embodiments where the opening / closing of tube valve 111 is controlled manually or directly in response to a signal from controller 118 (using, for example, tube set module 300 described below), the negative pressure delivered at step 604 may generally include any desired range of negative pressures, where step 604 includes verifying by the user and / or controller that tube valve 111 is in an open flow orientation before pneumatic pump 120 applies negative pressure. Figure 6C As illustrated, according to various embodiments, the drip tube valve 109 and the exhaust valve 113b can be configured to be disposed in a closed configuration during application of negative pressure to the negative pressure circuit 200 .

[0101] like Fig.6D As illustrated, at step 606, after a first desired negative pressure is reached within the negative pressure circuit 200 (such as the negative pressure measured by, for example, the pressure sensor 115a and / or the pressure sensor 115b and reported to the controller 118), the pneumatic pump 120 is stopped from operating, and the exhaust valve 113b is opened to allow air from the ambient environment surrounding the treatment device 102 to flow through the exhaust hole 113a and into the negative pressure circuit 200. According to various embodiments, the opening of the exhaust valve 113b at step 606 may be manually implemented by a user or in response to an instruction from the controller 118 transmitted to the tube set module 300. In other embodiments, the graduated leakage device 113 may be formed without the exhaust valve 113b (i.e., the exhaust hole 113a defines a constant leakage amount within the tube 110), so that air from the ambient environment surrounding the treatment device 102 will flow into the negative pressure circuit 200 without any user and / or controller 118 intervention.

[0102] As air from the surrounding environment flows into the negative pressure circuit 200, parameters related to the flow of air entering the negative pressure circuit 200 through the vent 113a are monitored (e.g., via the flow detector 113c, the pressure sensor 115a, the pressure sensor 115b, etc.), wherein the measured parameters are then used by the controller 118 to determine the volume of the negative pressure circuit 200 at step 612. According to various embodiments, the parameters related to the flow of air entering the negative pressure circuit 200 may include, for example: the rate of the flow of air entering the negative pressure circuit 200 (as measured by, for example, the flow detector 113c); the duration required for the pressure within the negative pressure circuit 200 to increase to a predetermined pressure (ambient pressure) after the vent 113a is opened and / or after the operation of the pump 120 is stopped; the changing pressure within the negative pressure circuit 200 as the pressure increases from the negative pressure applied at step 604 to the predetermined pressure (as measured by, for example, the pressure sensor 115a and / or the pressure sensor 115b), and the like.

[0103] Once the pressure within the negative pressure circuit 200 increases to the desired pressure and the controller 118 has completed the measurement of the desired parameter, the controller 118 can be configured to operate the pneumatic pump 120 to establish a second desired negative pressure within the portion of the negative pressure circuit 200 that removes the fluid tank circuit 202 at step 608, such as, for example Fig. 6E In embodiments where the tube valve 111 comprises a normally closed pressure-sensitive valve that can open in response to an applied predetermined threshold negative pressure, the second desired negative pressure generated by the controller 118 at step 608 may be less than the predetermined threshold pressure required to open the tube valve 111, so as to ensure that the vacuum applied by the pneumatic pump 120 at step 608 is applied only to the removal fluid tank circuit 202 portion of the negative pressure circuit 200. For example, in some embodiments, the threshold negative pressure required to open the tube valve 111 may be approximately negative 125 mmHg, wherein the controller 118 is configured to apply a negative pressure less than negative 125 mmHg, such as, for example, a pressure of approximately negative 50 mmHg, at step 608.

[0104] Alternatively, in embodiments where the opening / closing of the tube valve 111 is controlled manually or in direct response to a signal from the controller 118, the negative pressure delivered at step 608 may generally include any desired range of negative pressures, wherein step 608 includes verifying by the user and / or the controller that the tube valve 111 is in a closed, non-flowing orientation before the pneumatic pump 120 applies the negative pressure. It should be understood that in such embodiments, the second negative pressure applied by the controller 118 to the removal fluid tank circuit 202 at step 608 may include a pressure that is equal to or different from the negative pressure applied by the controller 118 to the negative pressure circuit 200 at step 604. For example, Fig. 6EAs illustrated, according to various embodiments, drip valve 109 and vent valve 113b may be configured to be placed in a closed configuration (manually or automatically, such as using tubing set module 300 ) during application of negative pressure to removal fluid tank circuit 202 at step 608 .

[0105] like Fig. 6F As illustrated, at step 610, after a second desired negative pressure is reached within the removal fluid tank circuit 202 (such as a negative pressure measured, for example, by the pressure sensor 115a and / or the pressure sensor 115b and reported to the controller 118), operation of the pneumatic pump 120 is stopped, and air from the ambient environment surrounding the treatment device 102 is allowed to flow through the vent 113a and into the removal fluid tank circuit 202. As air from the ambient environment flows into the removal fluid tank circuit 202, parameters associated with the air flow through the vent 113a and into the removal fluid tank circuit 202 are monitored, wherein the measured parameters are subsequently used by the controller 118 to calculate the volume of the removal fluid tank circuit 202 at step 612. According to various embodiments, parameters related to the air flow entering the removal fluid tank circuit 202 may include, for example: the rate of air flow entering the removal fluid tank circuit 202 (as measured by, for example, flow detector 113c); the duration required for the pressure within the removal fluid tank circuit 202 to increase to a predetermined pressure (e.g., ambient pressure) after the exhaust hole 113a is opened and / or the pump 120 is stopped at step 610; the pressure within the removal fluid tank circuit 202 as the pressure increases from the negative pressure applied at step 608 to the predetermined pressure (as measured by, for example, pressure sensor 115a and / or pressure sensor 115b), and the like.

[0106] At step 612, the controller 118 may be configured to determine the volumes of the fluid tank circuit 202 and the negative pressure circuit 200 to be removed based on the parameters measured at steps 606 and 610. According to some embodiments, the controller 118 may base these volume calculations on stored relationships between various measured parameter values ​​and corresponding volumes. These relationships between measured parameter measurements and corresponding volumes stored by the controller 118 may include various functions, models, lookup tables, etc., and may be based on existing information input and stored by the controller 118, or based on information obtained and processed by the controller 118 during an optional initial training process performed by the controller 118 prior to using the NPWT system 100 to treat the wound site 114 (e.g., prior to initiation of the method 500; as part of the initial setup and initial instillation of the instillation fluid at step 502, etc.). A non-limiting example of an implementation of a training process that may be used by the controller 118 to generate such a relationship is outlined in related co-pending U.S. provisional application 62 / 650,132, filed on April 17, 2018, entitled “WOUND THERAPY SYSTEM WITH WOUND VOLUME ESTIMATION,” the entire disclosure of which is incorporated herein by reference.

[0107] Using the determined volumes of the removal fluid tank circuit 202 and the negative pressure circuit 200, the controller 118 may determine the volume of the dead space 119 (i.e., the portion of the interior space defined between the wound site 114 and the lower surface of the drape layer 117 that is not occupied by the wound dressing 112 and / or any instillation fluid 105 / other fluid) at the wound site 114 by subtracting the volume of the removal fluid tank circuit 202 from the volume of the negative pressure circuit 200. According to various embodiments, determining the volume of the dead space 119 at the wound site 114 at step 614 may also include subtracting or otherwise adjusting the calculated difference between the volume of the removal fluid tank circuit 202 and the volume of the negative pressure circuit 200 to account for / account for the known volume of the downstream tube portion 110b and the known volume of the portion of the downstream drip tube 108b that extends between the drape layer 117 and the drip tube valve 109 in determining the volume of the dead space 119 at the wound site 114.

[0108] At step 614, an initial amount of the instillation fluid 105 to be delivered to the wound site 114 is calculated. According to various embodiments, the calculated initial amount of the instillation fluid 105 delivered to the wound site 114 may be based on the volume of the dead space 119 calculated by the controller 118 at step 612. For example, in some embodiments, the controller 118 may calculate the initial volume of the instillation fluid 105 to be delivered to the wound site 114 by multiplying the volume of the dead space 119 calculated at step 612 by a fluid instillation factor. The fluid instillation factor may be equal to or less than one (i.e., between zero and one) so that the volume of the instillation fluid 105 delivered to the wound site 114 does not exceed the available space within the drape layer 117, thereby reducing accidental leakage from the wound dressing 112 / drape layer 117. In some embodiments, the fluid instillation factor is between about 0.2 and about 0.8. However, it is contemplated that in various alternative embodiments, the fluid instillation factor may have any value.

[0109] As previously described with reference to step 510, in addition to being used to calculate the amount of instillation fluid 105 to be delivered during any treatment phase using the NPWT system 100 and under any number of different conditions (e.g., allowing additional instillation fluid 105 to be delivered to be calculated at step 516 even if the removal fluid canister 106 has been emptied or replaced entirely with a different sized removal fluid canister 106 during treatment), in some embodiments, the NPWT system 100 may additionally or alternatively be used to monitor and track the healing progress of the wound site 114 over time. Thus, in some embodiments, at step 616, an initial baseline wound site 114 volume estimate may optionally be determined by the controller 118 (via, for example, as described below with reference to Fig.11 The estimated value can be used as a reference point, and the volume estimate of the future wound site 114 can be compared with the reference point to track the healing progress of the wound site 114.

[0110] For reference Figure 5For reasons similar to those described in step 512 of method 500, according to some embodiments, at step 618, the amount of initial instillation fluid 105 to be delivered calculated at step 614 may be compared to the determined dead space 103 of the removal fluid tank 106 to determine whether the dead space within the removal fluid tank 106 will be sufficient to collect any fluid 121 (including unabsorbed instillation fluid 105) from the wound site 114 after the instillation fluid 105 is delivered at step 516. It should be understood that in embodiments where the NPWT system 100 has not been operated prior to using the NPWT system 100 at step 602, the volume of the removal fluid tank 106 should be empty such that the dead space 103 of the removal fluid container 106 should be equal to the volume of the removal fluid tank 106. If the volume of the removal fluid tank 106 is unknown at step 602 and / or if the removal fluid 107 is present in the removal fluid tank 106, the dead space 103 of the removal fluid container can be calculated by subtracting the known volume of the conduit 136 and the upstream tube portion 110a from the volume of the removal fluid tank circuit 202 determined at step 614. Similar to step 514, at step 620, if the initial volume of the instillation fluid 105 to be delivered calculated at step 614 exceeds the dead space 103 of the removal fluid tank 106, an alert can be issued to the user. Otherwise, if the volume of the initial instillation fluid 105 to be delivered does not exceed the dead space 103 of the removal fluid tank 106, the calculated instillation fluid 105 is delivered to the wound site 114 at step 622, such as, for example. Fig. 6F as shown in .

[0111] See also Figure 7 , showing the NPWT system 100 according to one embodiment in determining Figure 5 The method 500 of claim 500 is performed after the additional instillation fluid 105 is instilled into the wound site 114 at step 504, but before the wound void space at the wound site is determined at step 506. Figure 7 As shown in , at a time immediately prior to determining the dead space at the wound site 114 at step 506, a certain amount of fluid 121 (e.g., unabsorbed instillation fluid 105 from a previous instillation, wound exudate, etc.) may be present in the space between the drape layer 117 and the wound site 114, wherein the remaining space between the drape layer 117 and the wound site 114 defines an initial dead space 119a. Figure 7As shown in , according to some embodiments, at a time immediately before step 506 begins, an initial amount of removal fluid 107 may be present in removal fluid tank 106, wherein the remaining volume of removal fluid tank 106 is defined by initial dead space 103a. It should be understood that according to some embodiments, at a time immediately before step 506, there may be no fluid at wound site 114 and / or in removal fluid tank 106, in which embodiments, the amount of each of fluid 121 in the wound space and removal fluid 107 in removal fluid tank 106 will be equal to zero.

[0112] As described above, immediately prior to initiation of step 506, a quantity of fluid 121 may be present at wound site 114. According to some embodiments, Figure 5 In some embodiments of the method 500, it may be undesirable and / or unnecessary to remove fluid 121 in the wound site (e.g., unabsorbed instillation fluid 105 from a previous instillation, wound exudate, etc.) prior to delivering additional instillation fluid 105 to the wound site 114 at step 516 of the method 500. Therefore, in some embodiments of the method 500, the additional instillation fluid 105 instilled into the wound site at step 516 may be delivered to the wound site 114 without regard to any fluid 121 that may be present at the wound site 114.

[0113] See also FIG. 8A to FIG. 8E , illustrates one embodiment of a method 800 for determining an amount of dead space at a wound site 114, wherein Figure 5 At step 506 of method 500, the method may be used in embodiments where the fluid 121 in the wound site 114 is not removed from the wound site 114 prior to instilling additional instillation fluid 105. Specifically, according to FIG. 8A to FIG. 8E In method 800, since no fluid 121 is discharged from the wound site 114 during method 800 (i.e., step 506), the final dead space into which the additional instillation fluid 121 will drip will be the same initial dead space 119a at the wound site that existed immediately prior to initiation of step 506 (i.e., Figure 7 The dead space 119a shown in FIG.

[0114] like Fig. 8A As shown in the flowchart in FIG. 8 , the method 800 for determining the dead space is similar to the method 600 for calculating the dead space 119 after the instillation fluid 105 is initially instilled into the wound site 114 at step 502 (reference FIG. 6A to FIG. 6G Specifically, similar to steps 604 and 606, Fig. 8A The method 800 also includes steps 802 and 804 (e.g., respectively, Figure 8B and Figure 8C), during which negative pressure is applied to and removed from the negative pressure circuit 200. Fig. 6A 8 also includes steps 806 and 808 (e.g., respectively, in Fig.8D and Fig. 8E ), during these steps, negative pressure is applied to and removed from the removal fluid tank circuit 202. Fig. 6A Method 600, in FIG. 8A to FIG. 8E In the method 800, step 802 of applying negative pressure to the negative pressure circuit 200 and step 804 of subsequently removing the negative pressure may be performed before or after step 806 of applying negative pressure to the fluid tank circuit 202 and step 808 of subsequently removing the negative pressure.

[0115] As mentioned above, FIG. 8A to FIG. 8E The method 800 can be compared with the above reference Fig. 6A The method 600 is performed in substantially the same manner. However, as described above with reference to FIG. 6A to FIG. 6E As described in the method, according to various embodiments, any range of negative pressure may generally be applied to the negative pressure circuit 200 at step 604 of method 600, but the negative pressure applied to the negative pressure circuit 200 at step 802 of method 800 must be limited to a negative pressure that will not cause the fluid 121 at the wound site 114 to be discharged into the removal fluid tank 106.

[0116] After completing step 808, the controller 118 may be configured to Figure 5 At step 508 of method 500, the volume of the dead space 119a at the wound site 114 (which corresponds to the maximum volume of additional instillation fluid 105 that can be delivered to the wound site 114) is calculated. More specifically, at step 508, the volume of the removal fluid tank circuit 202 and the negative pressure circuit 200 is calculated based on the parameters measured at steps 804 and 808 (in a manner similar to that of reference 5). FIG. 6A to FIG. 6G After that, the dead space 119a at the wound site 114 can be calculated based on subtracting the measured volume of the removed fluid tank circuit 202 from the measured volume of the negative pressure circuit 200, where FIG. 8A to FIG. 8EThe volume of the removed fluid tank circuit 202 of method 800 is defined by the following items: the dead space 103a, the conduit 136 and the upstream tube portion 110a of the removed fluid tank 106; and the volume of the negative pressure circuit 200 is defined by the following items: the volume of the removed fluid tank circuit 202 (i.e., the dead space 103a, the conduit 136 and the upstream tube portion 110a of the removed fluid tank 106), the downstream tube portion 110b, the dead space 119a of the wound site 114, and the portion of the downstream drip tube 108b extending between the disinfection cover cloth layer 117 and the drip tube valve 109.

[0117] According to various embodiments, in an embodiment of method 500, the volume of dead space 119a at wound site 114 determined at step 508 is based on the use of FIG. 8A to FIG. 8E Based on the measured parameters related to the removal fluid tank circuit 202 and the negative pressure circuit 200 obtained by method 800, step 508 may also include subtracting or otherwise adjusting the calculated difference between the volume of the removal fluid tank circuit 202 and the volume of the negative pressure circuit 200 to take into account / account for the known volume of the downstream tube portion 110b and the known volume of the portion of the downstream drip tube 108b extending between the disinfection cover cloth layer 117 and the drip tube valve 109 in the process of determining the volume of the dead space 119a at the wound site 114.

[0118] Although as described above, in some embodiments of method 500, additional infusion fluid 105 can be delivered at step 516 without first removing any remaining fluid 121 at the wound site 114, according to other embodiments, it may be desirable to remove the fluid 121 in the wound site 114 before delivering the additional infusion fluid 105.

[0119] See also 9A to 9E , shows one embodiment of a method 900 for determining the amount of dead space at a wound site 114, wherein Figure 5 At step 506 of method 500, the method may be used in embodiments where it is desired to remove fluid 121 from wound site 114 prior to instilling additional instillation fluid 105. Specifically, according to 9A to 9E In method 900, during method 900 (i.e., step 506), any fluid 121 (e.g., Figure 7 ) is discharged from the wound site 114 so that the final dead space 119b into which the additional instillation fluid 121 will drip will be larger than the initial dead space 119a at the wound site immediately prior to initiation of step 506 by an amount that roughly corresponds to the volume of fluid 121 discharged from the wound site 114 into the removal fluid tank 106 during method 900.

[0120] like Fig.9A As shown in the flowchart in FIG. 1 , the method 900 for determining the dead space is similar to the method 600 for calculating the dead space 119 after the instillation fluid 105 is initially instilled into the wound site 114 at step 502 (see FIG. 1 ). FIG. 6A to FIG. 6G Specifically, similar to steps 604 and 606, Fig.9A The method 900 also includes steps 902 and 904 (e.g., respectively, Fig. 9B and Fig. 9C ), during which negative pressure is applied to and removed from the negative pressure circuit 200. Fig. 6A 608 and 610 of method 600, the method 900 of FIG. 9 also includes steps 906 and 908 (e.g., respectively in Fig.9D and Fig.9E ), during which steps negative pressure is applied to and removed from the removal fluid tank circuit 202.

[0121] However, with Fig. 6A Different from the method 600 of FIG. 6 , in which the step 604 of applying negative pressure to the negative pressure circuit 200 and the step 608 of subsequently removing the negative pressure may be performed before or after the step 610 of applying negative pressure to the fluid tank circuit 202 and the step 612 of subsequently removing the negative pressure, while in FIG. Fig.9A In the method 900, the step 902 of applying negative pressure to the negative pressure circuit 200 and the step 904 of subsequently removing the negative pressure are performed before the step 906 of applying negative pressure to the fluid tank circuit 202 and the step 908 of subsequently removing the negative pressure. FIG. 6A to FIG. 6E As described in the method of , according to various embodiments, generally any range of negative pressure can be applied to the negative pressure circuit 200 at step 604 of method 600, but in Fig.9A The negative pressure applied to the negative pressure circuit 200 at step 902 of method 900 must be sufficient to cause the fluid 121 to be discharged from the wound site 114 into the removal fluid tank 106.

[0122] After completing step 908, the controller 118 may be configured to Figure 5 At step 508 of method 500, the volume of the final dead space 119b at the wound site 114 (which corresponds to the maximum volume of additional instillation fluid 105 that can be delivered to the wound site 114) is calculated. More specifically, at step 508, the volume of the removal fluid tank circuit 202 and the negative pressure circuit 200 is calculated based on the parameters measured at steps 904 and 908 (in a manner similar to that of reference 5). FIG. 6A to FIG. 6G612 of method 600), the final dead space 119b at the wound site 114 can be calculated based on subtracting the measured volume of the removed fluid tank circuit 202 from the measured volume of the negative pressure circuit 200, where 9A to 9E The volume of the removal fluid tank loop 202 in the method 800 is defined by the following: the final dead space 103b of the removal fluid tank 106 (wherein at step 802, the final dead space 103b of the removal fluid tank 106 is approximately equal to the difference between the initial dead space 103a within the removal fluid tank 106 and the volume of the fluid 121 discharged from the wound site 114 into the removal fluid tank 106, such as, for example Fig. 9B as shown), conduit 136 and upstream tube portion 110a; and the volume of the negative pressure circuit 200 is defined by: the volume of the removal fluid tank circuit 202 (i.e., the final dead space 103b of the removal fluid tank 106, the conduit 136 and the upstream tube portion 110a), the downstream tube portion 110b, the final dead space 119b of the wound site 114, and the portion of the downstream drip tube 108b extending between the disinfection cover cloth layer 117 and the drip tube valve 109.

[0123] According to various embodiments, in an embodiment of method 500, the volume of dead space 119 at wound site 114 determined at step 508 is based on the use of 9A to 9E Based on the measured parameters related to the removal fluid tank circuit 202 and the negative pressure circuit 200 obtained by method 900, step 508 may also include subtracting or otherwise adjusting the calculated difference between the volume of the removal fluid tank circuit 202 and the volume of the negative pressure circuit 200 to take into account / account for the known volume of the downstream tube portion 110b and the known volume of the portion of the downstream drip tube 108b extending between the disinfection cover cloth layer 117 and the drip tube valve 109 in the process of determining the volume of the dead space 119a at the wound site 114.

[0124] exist Figure 5 In some embodiments of method 500, in which fluid 121 in the wound site 114 is removed prior to instilling additional instillation fluid 105 at step 516, it may be desirable to ensure that the initial dead space 103a in the removal fluid tank 106 is sufficient to contain the fluid 121 that will be expelled from the wound site 114 into the removal fluid tank during step 506, prior to initiating the step of determining the dead space at the wound site at step 506, so as to avoid the risk of overflowing the removal fluid tank 106.

[0125] Thus, in some embodiments of method 500, wherein fluid 121 in wound site 114 is removed prior to instilling any additional instillation fluid 105 at step 516, the method of step 506 of determining dead space at wound site 114 (e.g., such as with reference to 9A to 9E ) may include determining whether there is sufficient dead space at the removal fluid tank 106 to hold fluid 121 from the wound site 114 that can be discharged into the removal fluid tank 106, as part of a method for determining dead space at the wound site 114.

[0126] FIG. 10A to FIG. 10C One embodiment of such a method is illustrated, which may be used in step 506 of determining the dead space at the wound site 114 (e.g., via 9A to 9E The risk of spillage of the fluid tank 106 is minimized during the removal of the fluid tank 106 during the method 900 described above. Fig. 10B and Fig. 10C ), applying negative pressure to and removing negative pressure from the removal fluid tank circuit 202 to determine an initial dead space 103a in the removal fluid tank 106 before starting step 506 (e.g., as shown in FIG. Figure 7 Generally speaking, FIG. 10A to FIG. 1 Steps 1002 and 1004 of method 1000 of 0E may be combined with FIG. 6A to FIG. 6G Steps 608 and 610 of method 600 are performed in a substantially similar manner. At step 1006, the volume of the removed fluid tank circuit 202 is calculated based on the parameters measured at step 1004 (in a manner similar to that of reference 1). FIG. 6A to FIG. 6G Once the volume of the removal fluid tank circuit 202 is calculated, the known volumes of the conduit 136 and the upstream tube portion 110a can be subtracted from the calculated removal fluid tank circuit 202 to determine the volume of the initial dead space 103a in the removal fluid tank 106 (i.e., the maximum volume of fluid 121 discharged from the wound site 114 that the removal fluid tank 106 can hold).

[0127] Once the volume of the initial dead space 103a is calculated at step 1006, at step 1008, the controller 118 may be configured to estimate the volume of the fluid 121 at the wound site 114 at a time immediately prior to determining the dead space at the wound site 114 at step 506. The volume of the fluid 121 at the wound site 114 may be based on any number of different factors and variables, such as, for example, a stored value of the amount of instilled fluid 105 previously delivered to the wound site 114, a stored value of the fluid 121 previously removed from the wound site, an elapsed time (e.g., the elapsed time since the last instillation, the elapsed time since the last removal of the fluid 121, etc.), etc., wherein at step 1008, the controller 118 is further configured to compare this estimated volume of the fluid 121 to the initial dead space 103a calculated at step 1006, and if the controller 118 determines that the estimated volume of the fluid 121 exceeds the calculated initial dead space 103a, then alert the user to empty the removal fluid tank 106 at step 1010. If the calculated initial dead space 103a is sufficient to hold the estimated volume of fluid 121 from the wound site 114, then at step 1012, the controller 118 may be configured, for example, according to reference 9A to 9E The method 900 begins with step 506 of determining the dead space at the wound site 114 .

[0128] As described above, according to some embodiments of method 500 , it may be advantageous to monitor changes in the volume of wound site 114 at optional step 510 to track the progress of healing of wound site 114 .

[0129] Generally, the volume of the wound site 114 is defined by the entire interior that extends between the wound site 114 and the drape layer 117 attached to the skin 116 around the wound site 114. At various points during treatment using the NPWT system 100, located within and defining the volume of the wound site may be any one and any combination of the wound dressing 112, the fluid 121, and / or the dead space 119. It should be understood that unless the wound dressing 112 is replaced during treatment, the volume of the wound site 114 occupied by the wound dressing 112 will generally remain constant during treatment, while the portion of the volume of the wound site 114 occupied by the fluid 121 and / or the dead space 119 may change over time.

[0130] See also Fig.11 , a block diagram is shown, which illustrates that Figure 5An embodiment of a method 1100 for tracking the progress of healing of a wound site 114 used at step 510 of method 500. At step 1102, an initial volume of the wound site 114 is estimated and recorded by the controller 118 at a point in time prior to the initial instillation of the instillation fluid 105 into the wound site 114, and the initial volume may be used as a baseline to compare with subsequent volume estimates of the wound site 114 to track the progress of healing. According to various embodiments, the estimate of the initial volume of the wound site 114 made at step 1102 may be based on (or as a reference to) FIG. 6A to FIG. 6G Step 616 of method 600 is performed.

[0131] At step 1104, after estimating the initial volume of the wound site 114 at step 1102, at one or more additional times during treatment (e.g., once per day), an estimated volume of the wound site 114 is determined and recorded, wherein the time at which the volume of such one or more wound sites 114 is estimated and the determined volume value of the wound site 114 are stored as data points within a memory of the treatment device 102 and / or presented to a user as an output of the treatment device 102 (e.g., via the communication interface 124 or the user interface 126). In some embodiments, the estimated wound volume may be plotted as a function of time.

[0132] At step 1104, additional wound site 114 volume estimates determined at one or more additional times during treatment may be estimated according to any number of different processes. For example, according to some embodiments, the wound site 114 volume estimate recorded at step 1104 may be based on a final dead space volume at the wound site 114, such as by reference to, for example, Figure 5 508 of method 500 to calculate, and / or using reference such as 9A to 9E The method 900 is described for calculation.

[0133] like Figure 5 Step 510 and Fig. 6A As shown in step 616 of , according to some embodiments, the volume estimation of the wound site 114 at step 1102 and / or step 1104 may be performed in conjunction with a method of delivering the instillation fluid 105 to the wound site 114. However, it should be understood that according to other embodiments, the determination and recording of some, all, or zero of the volume estimation values ​​for the wound site 114 at step 1102 and / or step 1104 may be performed independently of any delivery of the instillation fluid 105 to the wound site 114.

[0134] Since additional wound site 114 volume estimates are obtained at step 1104, at step 1106, the estimated change in wound site 114 volume over time may be used to determine the healing progress of the wound site 114. For example, step 1106 may include comparing the wound site 114 volume estimate obtained at step 1104 with one or more previous estimates of the wound site 114 volume (estimates obtained at step 1104 or step 1102) to identify changes in the wound site 114 volume. In some embodiments, step 1006 may also include determining a rate at which the wound site 114 is healing based on the estimated change in the wound site 114 volume over time. In some embodiments, step 1106 may include extrapolating or predicting a time when the wound site 114 will be completely healed based on a series of wound site 114 volume estimates stored by the controller 118. For example, step 1106 may include predicting when the estimated wound site 114 volume will reach zero (or another threshold) based on the initial wound site 114 volume estimate obtained at step 1002 and a series of additional wound site 114 volume estimates obtained at step 1004 .

[0135] According to some embodiments, instead of or in addition to providing an indexed leak device 113 located upstream of the pipe valve 111, the NPWT system 100 may include an indexed leak device 113 located downstream of the pipe valve 111. Generally speaking, such embodiments in which the indexed leak device 113 is located downstream of the pipe valve 111 may be substantially similar to the embodiments described with reference to Figures 1 to 11 However, in contrast to the steps of monitoring the pressure decay within the removal fluid tank circuit 202, determining the volume of the removal fluid tank circuit 202 based on the monitored pressure decay, and then using the determined volume of the removal fluid tank circuit 202 to calculate the volume of the wound site 114, in Fig.12 In method 1200 , pressure decay is monitored within the wound site circuit 204 , and the determined volume of the wound site circuit 204 is then used to calculate the dead space 103 in the removal fluid tank 106 .

[0136] For example, see Fig.12 , shows a flow chart detailing the steps of a method 1200 for initial setup of an NPWT system 100 and delivery of an initial amount of instillation fluid 105 to a wound site 114, wherein a graduated leak device 113 of the NPWT system 100 is positioned downstream of a tube valve 111, according to one embodiment. In general, Fig.12 Steps 1202, 1204, and 1206 of the embodiment of method 1200 may be similar to those of reference Fig. 6A Steps 602, 604, and 606 of method 600 are performed in a substantially similar manner as described above.

[0137] At step 1208, the controller 118 is configured to initiate operation of the pump 120 to apply a second negative pressure (which may be equal to or different from the negative pressure applied by the controller 118 at step 1204) to the negative pressure circuit 200. According to various embodiments, the drip tube valve 109 and the vent valve 113b may be configured to be set to a closed configuration during the application of negative pressure to the negative pressure circuit 200 at step 1208. In embodiments in which a tube set module 300 controlled by the controller 118 is used, the controller 118 may be configured to instruct the tube set module 300 to effectuate closure of the priming tube valve 109 and / or the vent valve 113b.

[0138] At step 1210, after a second desired negative pressure is reached within the negative pressure circuit 200 (such as the negative pressure measured by, for example, pressure sensor 115a and / or pressure sensor 115b and reported to the controller 118), the tube valve 111 is closed to define the wound site circuit 204, the pneumatic pump 120 is stopped, and air from the ambient environment surrounding the treatment device 102 is allowed to flow through the exhaust hole 113a and into the wound site circuit 204. As air from the ambient environment flows into the wound site circuit 204, parameters associated with the air flow through the exhaust hole 113a and into the wound site circuit 204 are monitored, wherein the measured parameters are subsequently used by the controller 118 to calculate the volume of the wound site circuit 204 at step 1212. According to various embodiments, parameters related to the air flow entering the wound site circuit 204 may include, for example: the rate of air flow entering the wound site circuit 204 (as measured, for example, by flow detector 113c); the duration required for the pressure within the wound site circuit 204 to increase to a predetermined pressure (e.g., ambient pressure) after the exhaust hole 113a is opened and / or the pump 120 is stopped at step 1210; the pressure within the wound site circuit 204 as the pressure increases from the negative pressure applied at step 1208 to the predetermined pressure (as measured, for example, by pressure sensor 115b), and the like.

[0139] At step 1212, the controller 118 may be configured to determine the volume of the wound site circuit 204 based on the parameters measured during step 1208. According to some embodiments, the controller 118 may base the volume calculation of the wound site circuit 204 on stored relationships between various measured parameter values ​​and corresponding volumes. These relationships between measured parameter measurements and corresponding volumes stored by the controller 118 may include various functions, models, lookup tables, etc., and may be based on existing information input and stored by the controller 118, or based on information obtained and processed by the controller 118 during an optional initial training process performed by the controller 118 prior to using the NPWT system 100 to treat the wound site 114 (e.g., prior to initiation of the method 500; as part of the initial setup and initial instillation of the instillation fluid at step 502, etc.). A non-limiting example of an implementation of a training process that may be used by the controller 118 to generate such a relationship is outlined in related co-pending U.S. provisional application 62 / 650,132, filed on April 17, 2018, entitled “WOUND THERAPY SYSTEM WITH WOUND VOLUME ESTIMATION,” the entire disclosure of which is incorporated herein by reference.

[0140] Using the determined volume of the wound site circuit 204, the controller 118 can determine the volume of the dead space 119 at the wound site 114 (i.e., the portion of the interior space defined between the wound site 114 and the lower surface of the disinfection cover layer 117 that is not occupied by the wound dressing 112 and / or any drip fluid 105 / other fluid) by subtracting or otherwise adjusting the calculated volume of the wound site circuit 204 to take into account / account for the known volume of the downstream tube portion 110b and the portion of the downstream drip tube 108b extending between the disinfection cover layer 117 and the drip tube valve 109 in the determination of the volume of the dead space 119a at the wound site 114.

[0141] At step 1214, an initial amount of the instillation fluid 105 to be delivered to the wound site 114 is calculated. According to various embodiments, the calculated initial amount of the instillation fluid 105 delivered to the wound site 114 may be based on the volume of the dead space 119 calculated by the controller 118 at step 1212. For example, in some embodiments, the controller 118 may calculate the initial volume of the instillation fluid 105 to be delivered to the wound site 114 by multiplying the volume of the dead space 119 calculated at step 1212 by a fluid instillation factor. The fluid instillation factor may be equal to or less than one (i.e., between zero and one) so that the volume of the instillation fluid 105 delivered to the wound site 114 does not exceed the available space within the drape layer 117, thereby reducing accidental leakage from the wound dressing 112 / drape layer 117. In some embodiments, the fluid instillation factor is between about 0.2 and about 0.8. However, it is contemplated that in various alternative embodiments, the fluid instillation factor may have any value.

[0142] As previously described with reference to step 510, in addition to being used to calculate the amount of instillation fluid 105 to be delivered during any treatment phase using the NPWT system 100 and under any number of different conditions (e.g., allowing additional instillation fluid 105 to be delivered to be calculated at step 516 even if the removal fluid canister 106 has been emptied or replaced entirely with a different sized removal fluid canister 106 during treatment), in some embodiments, the NPWT system 100 may additionally or alternatively be used to monitor and track the healing progress of the wound site 114 over time. Thus, in some embodiments, at step 1216, an initial baseline wound site 114 volume estimate may optionally be determined by the controller 118 (via, for example, reference to Fig.11 The estimated value can be used as a reference point, and the volume estimate of the future wound site 114 can be compared with the reference point to track the healing progress of the wound site 114.

[0143] At step 1218, the dead space 103 of the removed fluid tank 106 may be calculated to determine whether the dead space within the removed fluid tank 106 will be sufficient to collect any fluid 121 (including unabsorbed instillation fluid 105) from the wound site 114 after the instillation fluid 105 is delivered at step 516. It should be understood that in embodiments where the NPWT system 100 has not been operated prior to using the NPWT system 100 at step 1202, the volume of the removed fluid tank 106 should be empty such that the dead space 103 of the removed fluid container 106 should be equal to the volume of the removed fluid tank 106.

[0144] The dead space 103 of the removed fluid container can be calculated by subtracting the known volume of the conduit 136 and the upstream tube portion 110a from the volume of the removed fluid tank circuit 202, which is determined by subtracting the volume of the wound site 204 calculated at step 1212 from the determined volume of the negative pressure circuit 200. It should be understood that the volume of the negative pressure circuit 200 can be determined in a manner similar to the method of determining the volume of the wound site circuit 204 at step 1212.

[0145] Similar to step 514, at step 1220, if the initial volume of the instillation fluid 105 to be delivered calculated at step 1214 exceeds the dead space 103 of the removal fluid tank 106, an alert may be issued to the user. Otherwise, if the volume of the initial instillation fluid 105 to be delivered does not exceed the dead space 103 of the removal fluid tank 106, the calculated instillation fluid 105 is delivered to the wound site 114 at step 1222.

[0146] It should be understood that in some NPWT system 100 embodiments where the graduated leakage device 113 is disposed upstream and downstream of the pipe valve 111, the graduated leakage device 113 may be configured to ... Fig. 6A The method 600 is the same as or similar to the method Fig.12 The NPWT system 100 may be operated in the same or similar manner as the method 1200 to estimate the volume of the wound site 114 and / or estimate the dead space 103 at the removal fluid tank 106 .

[0147] In other embodiments of the NPWT system 100 where both an upstream indexed leak device and a downstream indexed leak device 113 are provided, the Fig. 6A The method 600 is the same as or similar to the method and Fig.12 1200 to estimate the volume of the wound site 114 and / or estimate the dead space 103 at the removal fluid tank 106. For example, according to some embodiments, a modified method of operating the NPWT system 100 having both an upstream indexed leak device and a downstream indexed leak device 113 may include the following steps: monitoring the pressure decay within the negative pressure circuit 200 (such as, for example, step 606 of method 600 of FIG. 6 and / or Fig.12 monitoring the pressure decay within the removal fluid tank circuit 202 (such as, for example, described in step 610 of method 600 with reference to FIG. 6 ); and monitoring the pressure decay within the wound site circuit 204 (such as, for example, described in step 1206 of method 1200 with reference to FIG. 6 ). Fig.12 1200 as described in step 1210 of method 1200).

[0148] In such embodiments, based on direct measurement (e.g., using Fig.12The method 1200 of determining the volume of the wound site 114 can be compared with the method 1200 of determining the volume of the wound site 114 based on indirect measurements (e.g., using Fig. 6A The volume of the wound site 114 is compared to that calculated by the method 600 of FIG. 6A and is based on direct measurements (e.g., using Fig. 6A Method 600) determines that the dead space 103 at which the fluid tank 106 is removed can be compared to the dead space 103 at which the fluid tank 106 is removed based on indirect measurements (e.g., using Fig.12 In such embodiments, the controller 118 may be configured to generate an alarm or alert in response to a difference between the direct and indirect measurements of the volume of the wound site 114 and / or the dead space 103 at the removal fluid tank 106. By providing such redundancy to the dead space 103 calculations of the wound site 114 and / or the removal fluid tank 106, such embodiments may be configured to allow the NPWT system 100 to provide more accurate and reliable results.

[0149] It should be understood that, according to various embodiments, the controller 118 may be programmed to allow the NPWT system 100 to determine a volume relative to the wound site 114 by any or all of the methods described herein. Thus, while in some embodiments the controller 118 may optionally be pre-programmed to determine a volume relative to the wound site 114 by a specific method (e.g., 9A to 9E 900 embodiment of the method shown), automatically determines the volume of the infusion fluid 105 to be delivered, and the controller 118 may also optionally allow the user to: select any of the other modes of calculating the volume relative to the wound site 114 based on whether the user wants to, for example, remove fluid 121 in the wound site 114 before instilling additional infusion fluid 105; verify whether sufficient dead space 103a in the fluid tank 106 is removed before determining the dead space at the wound site 114; verify whether sufficient dead space 103b in the fluid tank 106 is removed before instilling the calculated amount of additional infusion fluid 105 to be delivered to the wound site 114; monitor changes in the volume of the wound site 114 to track the healing process; and so on.

[0150] Pipeline module

[0151] Although in some arrangements, some or all of the graduated leak device 113, tube valve 111, and / or drip tube valve 109 or other NPWT system 100 components may be configured to be manually operated / actuated / utilized by a user, as described above, according to various embodiments, some or all of these components may alternatively be configured to be operated / actuated / utilized by the controller 118 without any user assistance. In this way, implementations of systems / methods for determining the volume of instillation fluid to be delivered to a wound site, estimating the volume of a wound, monitoring the healing progress of a wound, and / or other uses of the NPWT system 100 may be fully automated using the controller 118, thereby allowing for easier use of the NPWT system 100.

[0152] By providing the NPWT system 100 with an automated means by which the controller 118 can control or otherwise interact with one or more of the graduated leakage device 113, the tube valve 111, the drip tube valve 109, and / or other components of the NPWT system 100, the tube set module 300 can increase the accuracy of the NPWT system 100. For example, given the ability of the controller 118 to independently actuate (i.e., without user intervention) the operation of the graduated leakage device 113, the tube valve 111, and / or the drip tube valve 109 elements using the tube set module 300, the controller 118 can be configured to increase the rate at which data related to instillation fluid volume estimation, wound site volume estimation, wound site 114 healing progress monitoring, and / or other functions of the NPWT system 100 are collected. By increasing the data points used to provide such information, the reliability of the information provided by the controller 118 can thereby be increased. Similarly, avoiding or minimizing user involvement provided by the tube set module 300 can facilitate (and thereby increase) the use of the apparatus described above with reference to the embodiments of the present invention. Fig.12 The described possibility of arranging the dual-indexed leakage device 113 thus also increases the reliability of the NPWT system 100 .

[0153] In general, the tube set module 300 includes a housing element 304 that houses a power source 301, a communication interface 302, and one or more actuatable elements 303 configured to be controlled by a controller 118. In some embodiments, the tube set module 300 may also optionally include one or more additional non-actuatable elements 305, such as, for example, a pressure sensor 115a and / or a pressure sensor 115b. According to embodiments in which the graduated leaking device 113 is not defined by a vent valve 113b and includes only a non-actuatable vent hole 113a, the non-actuatable element 305 may include such a graduated leaking device 113 formed without a vent valve 113b.

[0154] It should be understood that according to some embodiments, some or all of the actuatable elements 303 may be configured to be self-actuated. In some such embodiments, the actuatable elements 303 may include an internal actuator operably connected (via wired, wireless, or any other type of connection) to the power supply 301 and / or communication interface 302 of the tube group module 300, via which instructions and / or power received from the controller 118 are relayed to the actuator of the actuatable elements 303. In other such embodiments, such self-actuating actuatable elements 303 may separately include one or both of the power supply and / or communication interface (in addition to the power supply 301 and / or communication interface 302 of the tube group module). In such embodiments, the instructions from the controller 118 may be received directly from the controller by the communication interface of the actuatable elements 303, or may be received indirectly from the communication interface 302 of the tube group module 300 by the communication interface of the actuatable elements 303. In other embodiments, some or all of the actuatable elements 303 may be configured to be actuated by any number of different types of known actuators or combinations of known actuators housed by the housing element 303, wherein the actuators of the housing element 303 are configured to effectuate actuation of one or more actuatable elements 303 in response to instructions received from the controller 118.

[0155] The power source 301 may include any number and combination of energy sources configured to supply sufficient energy to the communication interface 302, the actuatable elements 303, and / or the non-actuatable elements 305 housed by the housing element 304 as required for the operation of the NPWT system 100. In some embodiments where some or all of the tubing set modules 300 are integrated into the treatment device 102, the power provided by the power source 301 of the housing element 304 may include the power source of the treatment device 102.

[0156] The communication interface 302 may include any number and combination of wired and / or wireless connections via which the tubing set module 300 may receive communications (such as, for example, actuation signals) from the controller 118. According to some embodiments, the communication interface 302 may also optionally be configured to send and / or receive information (such as, for example, information about the status of one or more actuatable elements 303 and / or non-actuatable elements 305 of the tubing set module 300) to and / or from the controller 118, other tubing set modules 300, the housing element 304, and / or other sources. In some embodiments in which some or all of the tubing set modules 300 are integrated into the therapeutic device 102, the communication interface 302 of the housing element 304 may be defined by a portion of the communication interface of the therapeutic device 102.

[0157] According to some arrangements, the tube set module 300 may be defined by a single housing element 304, wherein each of the actuatable elements 303 (e.g., upstream and / or downstream indexing leak devices 113, tube valves 111, and / or drip tube valves 109, etc.) and / or non-actuatable elements 305 will be controlled / utilized by the controller 118, thereby forming part of a single integrated housing element 304. In other embodiments, the tube set module 300 may be defined by a plurality of separate and distinct housing elements 304, wherein each housing element 304 is formed with one or more of the various actuatable elements 303 and / or non-actuatable elements 305 to be controlled / utilized by the controller 118.

[0158] According to various arrangements, the one or more housing elements 304 defining the tubeset module 300 may be provided as a separate, discrete, unitary component of the NPWT system 100, which may then be attached or otherwise incorporated into one or more other components of a new or existing NPWT system 100. In other arrangements, some or all of the one or more housing elements 304 defining the tubeset module 300 may be provided as an integrated part of one or more of the other components of the NPWT system 100.

[0159] For example, in some arrangements, some or all of the tubing set module 300 may be integrated into the wound dressing 112, wherein the portion of the tubing set module 300 provided with the wound dressing 112 is configured to be removed from the NPWT system 100 along with the removal of the wound dressing 112. Upon removal of the integrated wound dressing 112 / tubing set module 300, the entire wound dressing 112 / tubing set module 300 may be discarded. Alternatively, the tubing set module 300 may be removed from the wound dressing 112, the wound dressing 112 may then be discarded, and the tubing set module may optionally be reused with another wound dressing 112 and / or other NPWT system 100 components.

[0160] In other arrangements, some or all of the tubeset module 300 may be integrated into the removal fluid tank 106, wherein the portion of the tubeset module 300 provided with the removal fluid tank 106 is removed from the NPWT system 100 as the removal fluid tank 106 is removed from the NPWT system 100. In some such embodiments, the tubeset module 300 may be integrally formed with the removal fluid tank 106, while in other embodiments, the tubeset module 300 may be non-integrally formed with the removal fluid tank 106.

[0161] According to another arrangement, the tube set module 300 may be configured to be integrated in-line with one or both of the tubes 108 and / or 110. In such embodiments, the attachment adapter 400 may be provided on the tube set module 300 and / or one or both of the tubes 108 and / or 110 to facilitate a fluid-tight attachment of the tube set module 300 to the tubes 108 and / or 110. According to some embodiments, the attachment adapter 400 may be provided on the tube set module 300, wherein the attachment adapter 400 is configured to be able to directly form a fluid-tight attachment with one or both of the tubes 108 and / or 110, thereby allowing the formation of an NPWT system without the tube set module 300 and / or the graduated leak device 113, the tube valve 111 and / or the drip tube valve 109 being added with the tube set module 300 to provide the NPWT system 100 as disclosed herein.

[0162] In some arrangements, some or all of the tube set module 300 may be integrated into the housing of the treatment device 102. In such embodiments, the efficiency of using the NPWT system 100 may be increased, such as by incorporating the tube set module 300, including some or all of the graduated leak device 113, the tube valve 111, and / or the drip tube valve 109, into the housing of the treatment device 102, the time to set up the NPWT system 100 may be reduced as compared to the time that would otherwise be required to set up an NPWT system 100 in which some or all of the graduated leak device 113, the tube valve 111, and / or the drip tube valve 109 are provided as separate and discrete components of the NPWT system 100. Additionally, by incorporating the tube set module 300 into the housing of the treatment device 102, the NPWT system 100 as described herein may be provided regardless of the particular tubes, removal fluid canisters, wound dressings, or other components provided to define the NPWT system 100 to treat the wound site 114.

[0163] See also Figure 13 to Figure 1 6, various embodiments of a tubeset module 300 configured to allow for partially or fully automated control of the NPWT system 100 using a controller 118 are shown. It should be understood that, while reference has been made to the controller 118 being provided as part of the treatment device 102, it should be understood that, according to various arrangements, the controller 118 may be provided independently and remotely from the treatment device 102 and / or the NPWT system 100 (e.g., by a remote medical provider). In such embodiments, the remotely provided controller 118 may be configured to communicate directly with the tubeset module 300 and / or indirectly with the tubeset module 300 via a communication interface provided by the treatment device 102.

[0164] like Fig.13As exemplified in the embodiments of the NPWT system 100 of FIG. 1 , in some arrangements, the tube set module 300 is provided as a single integrated housing element 304 that houses an actuatable element 303 including a graduated leak device 113, a tube valve 111, and an optional irrigation tube valve 109. According to some embodiments, one or both of the tube valve 111 and the optionally provided irrigation tube valve 109 may include the same or different clamps. Fig.13 As shown in , the housing element 304 also contains a power source 301 which is configured to actuate the actuatable element 303 in response to instructions received from the controller 118 via the communication interface 302 .

[0165] Despite Fig.13 In the illustrated embodiment, a single integrated tube group module 300 is shown as being in series with both tube 108 and tube 110, but according to other arrangements (not shown), it should be understood that a first housing element 304 including a graduated leakage device 113 and a tube valve 111 may be provided in series with tube 110, and an optional second housing element 304 including a drip tube valve 109 may be provided in series with tube 110.

[0166] like Fig.13 , in some embodiments, the tube set module 300 may be integrally formed with the upstream tube portion 110a and / or the upstream irrigation tube 108a. According to some such embodiments, the upstream tube portion 110a and / or the upstream irrigation tube 108a integrally formed with the tube set module 300 may in turn be integrally formed with the treatment device 102. In such embodiments, the tube set module 300 is configured to be removably attached to the downstream tube portion 110b and / or the downstream drip tube 108b integrally formed with the wound dressing 112, such that after use of the NPWT system 100 with a first wound dressing 112, the treatment device 102 with the integrated upstream tube portion 110a and / or the upstream irrigation tube 108a and the tube set module 300 may be reused with a new second wound dressing 112. In other embodiments, such as, for example, Fig.14 As illustrated in the NPWT system 100 of FIG. 1 , some or all of the tube set modules 300 may alternatively be integrally formed with the wound dressing 112 , wherein the tube set modules 300 are configured to be removed from the NPWT system 100 as the wound dressing 112 is removed.

[0167] See also Fig.15 According to some embodiments of the NPWT system 100, the tube set module 300 may include a first housing element 304 that houses the graduated leakage device 113 and optionally the perfusion tube valve 109, the pressure sensor 115a and / or the pressure sensor 119 positioned in series with the tubes 108 and / or 110. The second housing element 304 including the tube valve 111 may be spaced apart from the first housing element 304. Fig.14 As shown in , according to some arrangements, the second housing element 304 can be integrated into the removal fluid tank 106. In other embodiments, the second housing element 304 can be alternatively incorporated into the treatment device 102, or can be disposed at a second location inline with the tube 110.

[0168] See also Fig.16A , a block diagram of a NPWT system 100 according to one embodiment is shown. Fig.16A As exemplified by the NPWT system 100 of FIG. 1 , according to some embodiments, fluid communication between some or all of the negative pressure circuit 200 and the surrounding environment may be provided by a deflation valve system 450 provided along the perfusion tube 108 as an alternative or in addition to the graduated leakage device 113. According to various embodiments, the deflation valve system 450 may include a structure similar to the graduated leakage device 113 (including graduated leakage device 113 embodiments that include any combination of vent 113a, vent valve 113b, and / or flow detector 113c components).

[0169] Also like Fig.16A As illustrated, in such NPWT system 100 embodiments, the tube valve 111 and / or the drip tube valve 109 may be replaced by a valve assembly 460 that is fluidly attached to the tube 110 at the junction between the upstream tube portion 110a and the downstream tube portion 110b, and is attached to the drip tube assembly at the junction between the upstream tube 108a and the downstream tube 108b, and the valve assembly may be actuated to a plurality of positions. In a first position, the valve assembly 460 may permit fluid to flow from the pneumatic pump 120 via the tube 110 to the wound site 114, and from the drip pump 104 via the drip tube 108 to the wound site 114. In a second position, the valve assembly 460 may permit fluid to flow from the pneumatic pump 120 via the tube 110 to the wound site 114, while blocking the flow of fluid from the drip pump 104 via the drip tube 108 to the wound site 114. In the third position, the valve assembly 460 can block the flow of fluid from the pneumatic pump 120 via the tube 110 to the wound site 114 while permitting fluid to flow from the drip pump 104 via the drip tube 108 to the wound site 114. In the fourth position, the valve assembly 460 can fluidly connect the upstream tube portion 110a with the upstream drip tube 108a, thereby isolating the downstream tube portion 110b, the downstream tube 108, and the wound dressing 112 from the remainder of the treatment device 102.

[0170] When in the first configuration, the valve assembly 460 defines a negative pressure circuit 200 defined by the tube 136, the fluid tank 106, the tube 110, the wound site 114, and the portion of the irrigation tube extending between the wound site 114 and the deflation valve 450. When in the fourth configuration, the valve assembly 460 defines a removal fluid tank circuit 202 defined by the tube 136, the fluid tank 106, the upstream tube portion 110a, and the portion of the upstream tube 108a extending between the valve assembly 460 and the deflation valve 450, and a wound site circuit 204 defined by the downstream tube portion 110b, the wound site 114, and the downstream tube 108b.

[0171] It should be understood that Fig.16A The valve assembly 460 and the purge valve 450 of the NPWT system 100 can be operated in a manner similar to the operation of the tube valve 111, the graduated leakage device and / or the drip tube valve 109 as described in any of the methods described herein to determine the volume of a wound site, estimate the volume of fluid to be instilled, monitor the progress of wound healing, or perform any other function using the NPWT system 100.

[0172] See also Fig. 16B , according to one embodiment, is shown as being configured for use in conjunction with a purge valve 450 (such as, for example Fig.16A The pipe group module 300 is used together with the NPWT system 100 shown in FIG. Fig. 16B 18. In the illustrated embodiment in which the deflation valve 450 is provided as a discrete component of the therapeutic device 112 that is capable of being automatically actuated by the controller 118, the tube set module 300 may include only a single actuatable element 303 defined by the valve assembly 460. It should be understood that in other embodiments (such as, for example, where the deflation valve 450 provided as part of the therapeutic device is not capable of being automatically actuated by the controller 118), the deflation valve 450 may be provided as part of the tube set module 300 that is partially or fully integrated into the therapeutic device 112.

[0173] Although in Fig.16A In the illustrated embodiment of the NPWT system 100, the deflation valve 450 is illustrated as being provided as part of the treatment device 112, but according to other embodiments, the deflation valve 450 may alternatively or additionally be provided as part of the upstream tube 108a. In such embodiments, the deflation valve 450 may therefore be provided as an actuatable element 303 of the tube set module 300.

[0174] It should be appreciated that the controller 118 may be configured to implement any number of different operations using the NPWT system 100 based on the selective fully automated actuation / interaction of some or all of the actuatable elements 303 and / or non-actuatable elements 305 of the tubeset module 300 according to any number of different methods and protocols. According to various embodiments, the sequence and / or combination of instructions transmitted by the controller 118 to the tubeset module 300 and / or information received by the controller 118 from the tubeset module 300 may be configured to automatically operate the tubeset module 300 in a manner that allows the controller 118 to automatically implement one or more of the methods 500, 600, 800, 900, 1000, 1100, 1200, etc.

[0175] Fig.17 17 is a method 1700 by which a controller 118 can utilize a tube set module 300 containing actuatable elements 303 and non-actuatable elements 305, the actuatable elements including tube valve 111, perfusion tube valve 109, and graduated leakage device 113, and the non-actuatable elements including one or both of pressure sensor 115a and / or pressure sensor 115b to detect a flow of fluid based on, for example, a reference signal. Figure 5 Method 500 and Fig. 6A The method 600 described in the invention automatically controls the NPWT system 100 to determine the dead space 119 at the wound site 114 .

[0176] At step 1701, in response to the controller 118 being activated to determine the dead space at the wound site 114 (such as, for example, Figure 5 At step 506 of method 500), the controller 118 may initiate communication with the tube set module 300 to confirm that the irrigation tube valve 109 and the exhaust valve 113b of the graduated leakage device 113 are closed and the tube valve 111 is open. If the irrigation tube valve 109 and / or the exhaust valve 113b are open, the controller 118 may instruct the tube set module 300 to actuate the irrigation tube valve 109 and / or the exhaust valve 113b to a closed configuration. Similarly, if the tube valve 111 is detected as closed by the controller 118, the controller 118 may transmit an instruction to the tube valve 111 via the communication interface 302 to actuate the opening of the tube valve 111.

[0177] Once the controller 118 receives confirmation via the communication interface 302 that the irrigation tube valve 109 and the exhaust valve 113b are closed and the tube valve 111 is open, the controller 118 can be configured to initiate operation of the pneumatic pump 120 to apply negative pressure to the negative pressure circuit 200 (such as, for example, reference Fig. 6ADuring operation of the pneumatic pump 120, at step 1703, the controller 118 may be configured to receive pressure readings corresponding to the pressure within the negative pressure circuit 200 from the pressure sensor 115a and / or the pressure sensor 115b. It should be understood that the pressure readings received by the controller 118 at step 1703 may be received continuously at predetermined intervals and / or in response to a specific request for pressure readings transmitted by the controller 118 to the tube set module 300 via the communication interface 302.

[0178] In response to receiving a pressure reading from the tube set module 300 indicating that the pressure within the negative pressure circuit 200 has reached a threshold pressure, at step 1705, the controller 118 may be configured to stop operation of the pneumatic pump 120 and transmit an actuation signal to the tube set module 300 that is configured to cause the exhaust valve 113b to open.

[0179] At step 1707, the controller 118 may be configured to receive a pressure reading corresponding to a pressure decay within the negative pressure circuit 200 from the pressure sensor 115a and / or the pressure sensor 115b, such as, for example, a reference signal. Fig. 6A The pressure readings received by the controller 118 at step 1707 may be received continuously at predetermined intervals or in response to a specific request for pressure readings transmitted by the controller 118 to the tube stack module 300 via the communication interface 302 .

[0180] Once the controller 118 receives a pressure reading from the tubing module 300 indicating that the pressure within the negative pressure circuit 200 has reached a threshold pressure (such as, for example, ambient pressure), at step 1709, the controller 118 can be configured to use the tubing module 300 to actuate the closure of the tubing valve 111 and the exhaust valve 113 b, and then apply negative pressure to the resulting removal fluid tank circuit 202 (such as, for example, at Fig. 6A during step 608 of method 600 ).

[0181] At step 1711, the controller 118 may again be configured to receive a pressure reading from the tubing stack module 300. The pressure readings received by the controller 118 at step 1711 may be received continuously at predetermined intervals or in response to a specific request for a pressure reading transmitted by the controller 118 to the tubing stack module 300 via the communication interface 302. In response to receiving a pressure reading from the tubing stack module 300 indicating that the pressure within the removal fluid tank circuit 202 has reached a threshold pressure, at step 1713, the controller 118 may be configured to stop operation of the pneumatic pump 120 and transmit an actuation signal to the tubing stack module 300 configured to cause the exhaust valve 113b to open.

[0182] At step 1715, the controller 118 may be configured to receive a pressure reading from the pressure sensor 115a corresponding to a pressure decay within the removal fluid tank circuit 202, such as, for example, reference Fig. 6A The pressure readings received by the controller 118 at step 1715 may be received continuously at predetermined intervals or in response to a specific request for pressure readings transmitted by the controller 118 to the tube stack module 300 via the communication interface 302 .

[0183] According to some embodiments, after step 1715, at step 1717, the controller 118 can be configured to actuate the opening of the drip tube valve 109 using the tube set module 300, and then drip the drip fluid into the wound site 114 (such as, for example, with reference to FIG. Figure 5 Step 516 of method 500 and / or Fig. 6A 622 of method 600).

[0184] Wound treatment system with internal alternating orifices

[0185] See now Fig.18 , shows an NPIWT system 2100 according to an exemplary embodiment. The NPIWT system 2100 includes a dressing 2102 and a treatment unit 2108, the dressing being fluidly connected to a canister 2104 via a first tube 2106, and the treatment unit being coupled to the canister 2104. Fig.18 As shown in FIG. 1 , the NPIWT system 2100 also includes an instillation fluid source 2110 that can be fluidly connected to the dressing 2102 via the treatment unit 2108 and the second tube 2112. The NPIWT system 2100 and its components may correspond to, be implemented with, be combined with, and / or otherwise provide the above referenced Figures 1 to 17 Various features of the described systems and methods. It should be understood that the present disclosure contemplates various combinations of the embodiments shown in the drawings.

[0186] The dressing 2102 is shown as being applied to a wound bed 2114. The dressing 2102 includes a drape 2116 sealed to the wound bed 2114 and a foam layer 2118 positioned between the drape 2116 and the wound bed 2114. In various embodiments, the dressing 2102 may include various layers and features. The drape 2116 may be made of a substantially airtight material (e.g., a polyurethane-based material) and may include an adhesive border that allows the drape to be sealed to the patient's skin around the wound bed 2114. The foam layer 2118 may include a manifold layer that allows airflow therethrough and facilitates the distribution of negative pressure across the wound bed 2114. A wound space 2120 is thereby established that includes an open volume in the foam layer 2118 (i.e., air can flow through the open volume) and is otherwise located between the drape 2116 and the wound bed 2114.

[0187] The first tube 2106 extends from the dressing 2102 to the canister 2104. According to an exemplary embodiment, the cross-section of the first tube 2106 is Fig.21 As shown in Fig.21 Described in detail, the first tube 2106 includes an inner lumen 2400 and one or more outer lumens 2402. The inner lumen 2400 provides fluid flow from the wound space 2120 into the tank 2104. The one or more outer lumens 2402 can be fluidly connected to the pressure sensor 2124 to facilitate measuring the pressure at the wound space 2120. As described below, the one or more outer lumens 2402 can also be fluidly connected to the valve 2126. It should be understood that although described as an inner lumen and an outer lumen in the examples herein, any geometric arrangement of multiple lumens can be used in various embodiments. The connection pad (e.g., a low pressure interface) 2121 is connected to the disinfection cover cloth 116 and facilitates connecting the first tube 106 to the dressing 2102.

[0188] The canister 2104 is configured to collect wound exudate (e.g., fluid, other debris) removed from the wound space 2120 via the first tube 2106. The canister 2104 can be in fluid communication with the wound space 2120 via the first tube 2106. The canister 2104, the first tube 2106, and the dressing 2102 thus define a sealed space that includes the wound space 120.

[0189] The treatment unit 2108 is coupled to the tank 2104 and includes a pneumatic pump 2122 that can be fluidly connected to the sealed space, a sensor 2124 configured and positioned to measure the pressure in the sealed space, a valve 2126 positioned between the sealed space and the environment, a user interface 2128, and a drip pump 2130 coupled to the second tube 2112. The treatment unit 2108 also includes a control circuit 2132 that is communicatively and operably coupled to (e.g., capable of exchanging electronic signals with) the pneumatic pump 2122, the sensor 2124, the valve 2126, the user interface 2128, and the drip pump 2130.

[0190] The pneumatic pump 2122 can be controlled by the control circuit 2132 and can be operated to pump (e.g., suck, remove) air from the canister 2104, the first tube 2106, and the wound space 2120 (i.e., from the sealed space). The pneumatic pump 2122 can thereby create a negative pressure in the sealed space relative to atmospheric pressure, for example, between 25 mmHg and 175 mmHg. The pneumatic pump 2122 can create a pressure differential that draws fluid and debris out of the wound space 2120, through the first tube 2106, and into the canister 2104.

[0191] Sensor 2124 is positioned and configured to measure the pressure in the sealed space. Fig.18As shown in , the pressure sensor 2124 is positioned to measure pressure via one or more outer lumens 2402. In other embodiments, the sensor 2124 may be included to measure the pressure elsewhere in the sealed space (e.g., in the tank 104). The sensor 2124 provides the pressure measurement results (e.g., digital values, analog signals) to the control circuit 2132. The control circuit 2132 can be configured to receive the pressure measurement results from the sensor 2124 and use the pressure measurement results in the control loop to generate a control signal for the pneumatic pump 2122, which causes the pneumatic pump 2122 to maintain a desired pressure in the sealed space or provide a desired pressure pattern in the sealed space.

[0192] The user interface 2128 may include a display screen, a touch screen, a speaker, a button, a switch, or any other element capable of providing information to a user or receiving input from a user. In some embodiments, the control circuit 2132 is configured to generate a graphical user interface and cause the graphical user interface to be displayed on the user interface 2128. The graphical user interface may include various information about the NPIWT provided by the NPIWT system 2100, such as information related to the pressure in the sealed space, the amount of instillation fluid to be provided, the schedule of negative pressure and instillation cycles, and / or the size of the wound space 2120. The user interface 2128 may allow a user to input commands and settings related to the operation of the treatment unit 2108. The control circuit 2132 may receive such inputs from the user interface 2128 and control the treatment unit 2108 based on these inputs.

[0193] The drip pump 2130 is configured to deliver drip fluid from the drip fluid source 2110 to the wound space 2120 via the second conduit 2112. The drip pump 2130 may be controlled by the control circuit 2132 to provide a desired amount of drip fluid to the wound space 2120, to provide drip fluid to the wound space 2120 at a desired rate, to prevent the drip fluid from flowing to the wound space 2120, or to otherwise control the flow of drip fluid to the wound space 2120. The drip pump may include a peristaltic pump or some other type of pump.

[0194] Valve 2126 can be controlled between an open position and a closed position. Fig.18 As shown in , valve 2126 is positioned at the interior of treatment unit 2108, which is pneumatically connected to the surrounding environment (e.g., ambient air) via exhaust holes 2134 positioned along the exterior of treatment unit 2108. Valve 2126 is also shown as being in communication with one or more outer lumens 2402 of first tube 2106. . Filter 2138 is positioned between tank 2104 and pump 2122. When valve 2126 is in an open position, air can flow between the surrounding environment and the sealed space via filter 2138. When valve 2126 is in a closed position, air is prevented from flowing therethrough. As shown in FIG. Fig.19 and Fig. 20 As shown in and described in detail with reference to, valve 2126 may be a solenoid valve. In various other embodiments, other types of valves may be included. As described in detail below, valve 2126 may be controllable to allow a sudden surge ("jet") of air passing therethrough in a manner intended to clear an obstruction in one or more outer lumens 2402 of first tube 2106. Valve 2126 may also be controllable to achieve a controlled airflow rate therethrough to help determine the volume of wound space 2120.

[0195] The filter 2138 is configured to prevent contaminants from moving from the surrounding environment to the wound space 2120 via the valve 2126 and the one or more outer lumens 2402. The filter 2138 thereby protects the wound 2114 from infection or other complications. The filter 2138 limits the rate at which air flows from the surrounding environment through the filter 2138 into the sealed space (e.g., by creating a pressure drop across the filter 2138 due to the filter media, contaminants trapped in the filter media, etc.) to a maximum value of a limiting rate of the filter 2138. The limiting rate may be difficult to determine, may vary over time, or may be different in different instances of the filter 2138 (i.e., different across multiple treatment units 108).

[0196] In the illustrated embodiment, when the valve 2126 is maintained in the open position for an extended amount of time (e.g., 500 milliseconds or longer), the restriction rate of the filter is less than the typical rate of gas flow through the valve 2126. Therefore, when the valve 2126 is maintained in the open position for an extended amount of time, it is difficult to determine the restriction rate of the filter 2138 resulting in difficulty in determining the gas flow rate into the sealed space.

[0197] The control circuit 2132 is configured to control the operation of the treatment device 2108. For example, as described in detail below, the control circuit 2132 is configured to control the pneumatic pump 2112 to remove air from the sealed space to establish a negative pressure in the sealed space, control the valve 2126 to provide a controlled leak to the sealed space, receive pressure measurements from the sensor 2122, determine the volume of the wound space 2120 based on the pressure measurements, and customize the wound treatment based on the volume of the wound space 2120. In some embodiments, the control circuit 2132 is also configured to detect a potential obstruction of the lumen of the first tube 2106, control the valve 2126 to an open position to allow a puff of air to pass therethrough, maintain the valve 2126 open while the puff of air clears the obstruction, and control the valve 2126 back to a closed position. These and other features of the control circuit 2132 are described in detail below.

[0198] See now Figure 19 to Figure 20 , shows a cross-sectional view of a valve 2126 according to an exemplary embodiment. In the illustrated embodiment, the valve 2126 is a solenoid valve. Fig.19 The valve 2126 is shown in a closed position, and Fig. 20 The valve is shown in an open position. It should be understood that Figures 19 to 20 One of many possible implementations of valve 2126 is shown.

[0199] The valve 2126 includes an inlet 2200 that can be pneumatically connected to the surrounding environment via a vent 2134, an outlet 2202 that can be pneumatically connected to the sealed space via a passage 2136, a solenoid 2206, a plunger 2204 that extends axially through the solenoid 2206 and is substantially centered in the solenoid, a stopper 2205 coupled to the plunger 2204, and a spring 2208 coupled to the plunger 2204. The solenoid 2206 has a positive lead 2210 and a negative lead 2212, which are shown as being operably coupled (e.g., conductively coupled) to the control circuit 2132.

[0200] The solenoid 2206 includes a coil of wire through which the plunger 2204 extends. When current flows through the solenoid (e.g., when a voltage difference is applied across the solenoid 2206), a magnetic field is generated in the solenoid 2206. The magnetic field is substantially aligned with the central axis of the solenoid. The plunger 2204 is made of a magnetic material so that when a voltage is applied across the solenoid 2206, the magnetic field causes movement of the plunger 2204.

[0201] like Fig.19 , a voltage of approximately zero volts is applied across the solenoid 2206. That is, the control circuit 2132 prevents a voltage difference between the positive lead 2210 and the negative lead 2212. Therefore, approximately zero current is generated in the solenoid 2206, and approximately zero magnetic field is generated by the solenoid 2206. The spring 2208 exerts a force on the plunger 2204, which holds the stopper 2205 near the inlet 2200. The stopper 2205 prevents air from entering the valve 2206 via the inlet 2200. Airflow from the vent 2134 to the passage 2136 is thereby prevented (i.e., the valve 126 is in a closed position).

[0202] like Fig. 20 , a non-zero voltage (e.g., about 5 volts) is applied across the solenoid. That is, the control circuit 2132 provides a control signal to the valve 2126 by generating a voltage difference between the positive lead 2210 and the negative lead 2212 of the solenoid 2206. It should be understood that in various embodiments, various non-zero voltage values ​​may be required to operate the valve 2126. When the control circuit 2132 provides a non-zero voltage to the valve 2126 (i.e., across the solenoid 2206), a magnetic field is generated that causes the plunger 2204 to compress the spring 2208 and move the stopper 2205 away from the inlet 2200. Air can then flow from the exhaust hole 2134 through the valve 2126 to the sealed space (i.e., the valve 2126 is in the open position).

[0203] When the non-zero voltage is removed (i.e., when the voltage difference between the positive lead 2210 and the negative lead 2212 reaches approximately zero), the magnetic field becomes zero, and the spring 2208 forces the plunger 2204 and the stopper 2205 back to the Fig.19 Thus, valve 2126 may be controlled by alternating between approximately zero voltage and approximately non-zero voltage to Fig.19 The closed position shown in Fig. 20 21. Exemplary voltage patterns for controlling valve 2126 to provide a controlled gas flow rate therethrough are described in detail below.

[0204] See now Fig.21 , shows a cross-sectional view of the first tube 2106 according to an exemplary embodiment. In the illustrated embodiment, the first tube 2106 includes an inner lumen 2400 and four outer lumens 2402. That is, the first tube 2106 is shown as including five separate lumens (e.g., channels, holes, paths) through which air, fluids, and / or other debris can flow. Preferably, fluids and debris flow primarily through the inner lumen 2400, while air flows through the outer lumens 2402. At or near the tank 2104, the paths of the outer lumens 2402 are separated from the paths of the inner lumens 2400, as shown in FIG. Fig.18 21. The inner lumen 2400 is connected to the inner volume of the canister to allow fluid and debris from the wound space 2120 to be collected in the canister. The outer lumen 2402 is connected to the sensor 2124 to facilitate measuring and monitoring the pressure at the wound space.

[0205] The connection pad 2121 may include grooves and other physical features configured to direct fluid and debris toward the inner lumen 2400 and away from the outer lumen 2402. However, fluid and debris may occasionally reach one or more of the outer lumens 2402 and cause one or more of the outer lumens 2402 to become blocked. Blockage of the inner lumen 2400 may also occur. Fig. 22 As described, the valve 2126 can be controlled to allow a puff of air to be released through the outer lumen 2402 , thereby clearing fluid or other obstructions from the outer lumen 2402 , i.e., by pushing air and fluid back into the dressing 2102 and out of the outer lumen 2402 .

[0206] See now Fig. 22, a flow chart of a method 2500 for clearing an obstruction in a first tube 2106 is shown according to an exemplary embodiment. At step 2502, a potential obstruction of one or more outer lumens 2402 is determined. As one example, the control circuit 2132 can detect the obstruction based on the pressure measurement from the sensor 2124. As another example, the control circuit 2132 assumes that a potential obstruction exists after a predetermined period of time, i.e., causes steps 2504-2508 to be triggered at a predetermined frequency.

[0207] At step 2504, valve 2126 is opened to allow a puff of air to pass therethrough. For example, control circuit 2132 may provide a non-zero voltage to solenoid 2206 of valve 2126. Control circuit 2132 may maintain valve 2126 in an open position for an extended period of time, i.e., longer than 2504. Fig. 22 2106. The time period shown in and described below with reference thereto is longer. For example, in one embodiment, a non-zero voltage is provided for approximately 500 milliseconds to keep the valve 126 open for approximately 500 milliseconds. When the valve 2126 remains open, a stream of air can flow through it at a high airflow rate due to the pressure difference between the surrounding environment (ambient air) and the sealed space. The stream of air can flow into the blocked outer lumen 2402 and push any blockage out of the first tube 2106 toward the dressing 2106. The blockage in the outer lumen 2402 can thus be periodically cleared to allow free airflow through the outer lumen 2402, for example to ensure that the measurement result of the pressure sensor 2124 accurately represents the pressure at the wound space 2120.

[0208] At step 2506, the solenoid valve 2508 is closed. For example, the control circuit 2132 provides approximately zero voltage across the solenoid 2206. Airflow from the environment to the sealed space is prevented. The pneumatic pump 2122 can be operated to reestablish the desired negative pressure at the wound space 2120.

[0209] See now Fig.23 , a flow chart of a method 2600 for wound volume determination and wound treatment customization according to an exemplary embodiment is shown. The method 2600 may be performed by Fig.18 The NPIWT system 100 performs.

[0210] At step 2602, a sealed space defined by wound 2114, dressing 2102, first tube 2106, and tank 2104 is established. The sealed space includes wound space 2120. In other words, dressing 2102 is applied to wound 2114 with drape 2116 sealed over wound 2114 and foam layer 2118 (or other layers included in dressing 2102 in various embodiments) to define wound space 2120. First tube 2106 is coupled to drape 2116 in fluid communication with wound space 2120 via connection pad 2121. First tube 2106 is also coupled to tank 2104 in fluid communication with tank 2104.

[0211] At step 2604, the pneumatic pump 2122 is operated to draw negative pressure in the sealed space. That is, the control circuit 2132 provides a control signal to the pneumatic pump 2122, which causes the pneumatic pump to remove air from the sealed space. The control circuit 2132 may receive pressure measurements from the pressure sensor 2124, and stop the pneumatic pump 2122 when a desired negative pressure (e.g., -125 mmHg) is reached, and / or control the pneumatic pump 2122 in other ways based on the pressure measurements to provide a desired negative pressure or a desired negative pressure pattern.

[0212] At step 2606, valve 2126 is repeatedly opened and closed (e.g., "cycled") to achieve a controlled airflow rate therethrough. Control circuit 2132 may provide a control signal to valve 2126 that causes valve 2126 to repeatedly open and close. For example, in an embodiment where valve 2126 is a solenoid valve, such as Figures 19 to 20 In the example shown, at step 2606, the control circuit 2132 provides a voltage pattern to the valve 2126. That is, the control circuit 2132 can cause the voltage difference between the positive lead 2210 and the negative lead 2212 to repeatedly alternate between approximately zero volts and a non-zero voltage (e.g., approximately five volts). For example, the voltage pattern can include a step function that repeatedly steps between approximately zero voltage and a non-zero voltage.

[0213] In one example, if Fig.24 As shown in and described in detail with reference to it, the voltage pattern may include a repetitive pattern of about 400 milliseconds at a non-zero voltage, about 100 milliseconds at about zero voltage, about 400 milliseconds at a non-zero voltage, and about 100 milliseconds at about zero voltage. The voltage pattern may thus cause valve 2126 to alternate between an open position and a closed position with a period of about 500 milliseconds. In some embodiments, the voltage pattern may include a first set of two repetitions of the repetitive pattern, followed by about one second at about zero voltage, followed by a second set of two repetitions of the repetitive pattern. In a preferred embodiment, a non-zero voltage is provided in each repetition for a maximum continuous duration of no more than about 500 milliseconds.

[0214] By controlling valve 2126 to repeatedly alternate between open position and closed position, a controlled airflow rate passing therethrough is achieved in a repetitive process. That is, a lower airflow rate is allowed to pass through valve 2126 than by keeping valve 2126 open for an extended or uncertain amount of time (e.g., as described for method 500) such as 500 milliseconds or longer. The controlled rate can be customized by changing the voltage pattern. In addition, based on the voltage pattern, the controlled rate can be known. For example, for each voltage pattern in one or more voltage patterns, the controlled rate can be predetermined by bench testing. In a preferred embodiment, the controlled rate is less than the limiting rate of filter 2138.

[0215] At step 608, as the negative pressure in the sealed space decays toward ambient pressure (i.e., close to about atmospheric pressure), the pressure in the sealed space is measured. The controlled airflow through valve 2126 allows air to enter the sealed space and causes the pressure in the sealed space to decay toward ambient pressure. Sensor 2124 can measure the pressure in the sealed space and provide the pressure measurement result to control circuit 2132. Control circuit 2132 can record (store, save) the pressure measurement result. In some embodiments, control circuit 2132 can collect the pressure measurement results to form a pressure decay curve.

[0216] At step 610, the volume of the wound space 2120 is determined based on the pressure measurements. For example, based on the known controlled airflow rate through the valve 2126 and the measured pressure decay curve, the volume of the sealed space can be determined. The volume of the wound space can then be determined by removing the volume of the canister and tube from the total volume of the sealed space. In some cases, one or more additional valves, sensors, etc. are included to facilitate the generation and collection of data for wound size determination. In various embodiments, various methods for calculating wound size are possible, for example, as described with reference to Figures 1 to 17 described.

[0217] At step 2612, the wound size (e.g., the volume of the wound space 2120) and / or a message related thereto is displayed on the user interface 2128. For example, the control circuit 2130 may cause a graphical user interface including the wound size to be displayed on the screen of the user interface 2128. As another example, the control circuit 2130 may determine one or more warnings, progress reports, or other wound-related messages based on the wound size, and control the user interface 2128 to display the warnings, reports, or other messages. For example, the user interface 2128 may display a graphical representation of the change in the volume of the wound space over time.

[0218] At step 2614, wound therapy is customized based on the volume of the wound space. In some embodiments, the control circuit 2130 automatically customizes the wound therapy based on the determined volume of the wound space 2120. In other embodiments, a user is facilitated to customize the wound therapy based on the volume of the wound space 2120 based on information displayed on the user interface 2128.

[0219] In the example shown, the control circuit 2130 automatically customizes the instillation by automatically determining the amount of instillation fluid to be supplied to the wound space 2120 based on the determined volume of the wound space 2120. For example, the control circuit 2130 may multiply the determined volume of the wound space 2120 by a scaling factor to determine the amount of instillation fluid to be supplied to the wound space 2120. For another example, the control circuit 2130 may determine the instillation amount to be supplied to be equal to the volume of the wound space 2120. Various calculations may be performed for various applications, wound types, instillation fluid types, patient and / or caregiver preferences, etc.

[0220] At step 2616, customized wound therapy is provided. For example, the control circuit 2130 may control the instillation pump 2130 to provide the determined amount of instillation fluid from the instillation fluid source 2110 to the wound space 2120. The instillation therapy can thus be customized to meet the needs of the healing wound in real time. In various embodiments, various other customized therapies are possible.

[0221] See now Fig.24 , shows a set of graphs illustrating the operation of the NPIWT system 2100 according to an exemplary embodiment. Fig.24 A measured pressure graph 2700, a control signal graph 2702, and an introduced pressure graph 2704 are shown. The pressure graph 2700 shows the change in pressure in the sealed space measured by the pressure sensor 2124 over time. As shown in the pressure graph 2700, when the pneumatic pump 2122 is operated to pump air out of the sealed space, the measured pressure line 2706 approaches the desired negative pressure (shown as -200 mmHg). The measured pressure then decays as the valve 2126 is controlled to allow a controlled airflow rate therethrough.

[0222] The control signal graph 2702 shows the voltage pattern applied to the valve 2126 (i.e., across the solenoid 2206). As shown, the control signal 2708 alternates between approximately zero voltage and non-zero voltage (shown as approximately five volts). As shown, the control signal includes approximately 400 milliseconds at non-zero voltage, approximately 100 milliseconds at approximately zero voltage, another approximately 400 milliseconds at non-zero voltage, and another approximately 100 milliseconds at approximately zero voltage. After these two repetitions (i.e., after two cycles of 500 milliseconds), the control signal may include approximately zero voltage for one second, such as Fig.24. It should be understood that in various embodiments, various other frequencies and periods of the voltage pattern may be used. As a possible additional example, in an alternative embodiment, the voltage pattern alternates between about 200 milliseconds at a non-zero voltage and 50 milliseconds at about zero voltage for three or more repetitions (e.g., four repetitions), followed by about one second at about zero voltage before repeating the voltage pattern. In various embodiments, the non-zero voltage is repeatedly provided for a duration between a minimum continuous duration of about 50 milliseconds and a maximum continuous duration of about 500 milliseconds, wherein the alternating period is about zero voltage.

[0223] The pressure graph 2704 introduced shows the amount of pressure entering the sealed space over time. In the example shown, for each 400 millisecond segment of the non-zero voltage in the control signal 708, about 5 mmHg is introduced into the sealed space. The pressure graph 2704 introduced shows that the pressure decay in the sealed space can be managed by the alternating mode of the valve 2126 (i.e., the control signal 2708). For example, the pressure graph 2704 introduced indicates that the lag time may exist between the beginning of the non-zero voltage cycle and the peak rate corresponding to the pressure reduction or the peak rate of the gas flow through the valve 2126.

[0224] Referring now to FIG. 8 , in an alternative embodiment, a Fig.18 NPIWT system 2100. In the illustrated embodiment, the volume of the containment space and / or wound space can be determined by first determining the restriction rate of the filter 2138 (i.e., the rate of airflow through the filter 2138) as part of a calibration process prior to initiating treatment. Fig.18 , a removable cap (structure, cover, joint) 2800 is placed near the point where the inner lumen 2400 and the outer lumen 2402 come together to form the first tube 2106 (e.g., at the end of the canister 2104). For example, the first tube 2106 can be disconnected at this point and replaced by the removable cap 2800, as shown in FIG8. The removable cap 2800 connects the inner lumen 2400 and the outer lumen 2402 and allows air to flow directly between the two (i.e., without passing through the dressing 2102) during the process for determining the limiting rate of the filter 2138. The removable cap 2800 can then be removed and the first tube 2106 can be connected in the configuration described above.

[0225] To determine the limiting rate of the filter 2138 when the removable cover 2800 is applied as in FIG. 8 , the valve 2126 is closed and the pneumatic pump 2122 is run to remove air from the canister 2104. The valve 2126 can then be opened indefinitely to allow air to flow back into the canister 2104 while the pressure sensor 2124 measures the change in pressure over time. Based on the known volume of the canister 2104 and the change in pressure over time when the valve 2126 is open, the control circuit 2132 can calculate the rate of airflow through the filter. The cover 2800 facilitates this process by ensuring that the unknown volume of the wound space does not affect the rate of change of pressure during this process.

[0226] Configuration of the exemplary embodiment

[0227] As used herein, the terms "approximately," "about," "substantially," and similar terms are intended to have a broad meaning consistent with the common and recognized usage of those of ordinary skill in the art to which the subject matter of the present disclosure relates. Those skilled in the art who review the present disclosure should understand that these terms are intended to allow certain features to be described and claimed without limiting the scope of those features to the precise numerical ranges provided. Therefore, these terms should be interpreted as indicating insubstantial or inconsequential modifications or alterations of the subject matter described and claimed, and are considered to be within the scope of the present disclosure as set forth in the appended claims.

[0228] It should be noted that the term "exemplary" and variations thereof as used herein to describe various embodiments are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to imply that such embodiments are necessarily the particular or most advanced examples).

[0229] As used herein, the term "coupled" and variations thereof mean the direct or indirect engagement of two components with one another. Such engagement may be static (e.g., permanent or fixed) or movable (e.g., removable or releasable). Such engagement may be achieved with two components directly coupled to one another, with two components coupled to one another using a separate intermediate component and any additional intermediate components coupled to one another, or with two components coupled to one another using an intermediate component that is integrally formed with one of the two components as a single, unitary body. If "coupled" or variations thereof are modified by additional terms (e.g., directly coupled), the general definition of "coupled" provided above is modified by the ordinary language meaning of the additional terms (e.g., "directly coupled" means the engagement of two components without any separate intermediate component), resulting in a narrower definition than the general definition of "coupled" provided above. Such coupling may be mechanical, electrical, or fluidic.

[0230] References to element positions (e.g., "top," "bottom," "above," "below") herein are only used to describe the orientation of various elements in the figure. It should be noted that, according to other exemplary embodiments, the orientation of various elements may be different, and such variations are intended to be encompassed by the present disclosure. Although the accompanying drawings show the specific order of method steps, the order of steps may be different from the order depicted. Moreover, two or more steps may be performed simultaneously or partially simultaneously. Such variations will depend on the selected software and hardware systems and the designer's choice. All such variations are within the scope of the present disclosure. Similarly, software implementations can be implemented by standard programming techniques with rule-based logic and other logic to implement various connection steps, calculation steps, processing steps, comparison steps, and decision steps.

[0231] The construction and arrangement of the system and method shown in various exemplary embodiments are only exemplary. Although only several embodiments are described in detail in the present disclosure, many modifications are possible (for example, the size, size, structure, shape and ratio changes, parameter values, installation arrangements, use of materials, colors, orientations, etc. of various elements). For example, the position of the element can be reversed or otherwise changed, and the property or quantity or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present disclosure. The order or sequence of any process or method step can be changed or reordered according to an alternative embodiment. Without departing from the scope of the present disclosure, other replacements, modifications, changes and omissions can be made to the design, operating conditions and arrangement of the exemplary embodiments.

[0232] As used herein, the term "circuit" may include hardware structured to perform the functions described herein. In some embodiments, each corresponding "circuit" may include a machine-readable medium for configuring hardware to perform the functions described herein. The circuit may be embodied as one or more circuit components, including but not limited to processing circuits, network interfaces, peripherals, input devices, output devices, sensors, etc. In some embodiments, the circuit may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (ICs), discrete circuits, system-on-chip (SOC) circuits, etc.), telecommunications circuits, hybrid circuits, and any other type of "circuit". In this regard, a "circuit" may include any type of component for completing or facilitating the implementation of the operations described herein. For example, the circuit described herein may include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, etc.

[0233] "Circuit" may also include one or more processors that can be connected to one or more memories or memory devices. In this regard, the one or more processors may execute instructions stored in the memory, or may execute instructions that can access the one or more processors in other ways. In some embodiments, the one or more processors may be embodied in various ways. The one or more processors may be constructed in a manner sufficient to perform at least the operations described herein. In some embodiments, one or more processors may be shared by multiple circuits (for example, circuit A and circuit B may include or otherwise share the same processor, and in some exemplary embodiments, the same processor may execute instructions stored or otherwise accessed via different areas of the memory). Alternatively or in addition thereto, one or more processors may be structured to perform or otherwise perform certain operations independently of one or more coprocessors. In other exemplary embodiments, two or more processors may be connected by a bus to enable independent, parallel, pipelined or multithreaded instruction execution. Each processor may be implemented as one or more general-purpose processors, application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs) or other suitable electronic data processing components structured to perform instructions provided by the memory. One or more processors may take the form of a single-core processor, a multi-core processor (e.g., a dual-core processor, a triple-core processor, a quad-core processor, etc.), a microprocessor, etc. In some embodiments, one or more processors may be located outside the device, for example, one or more processors may be remote processors (e.g., cloud-based processors). Alternatively or in addition, one or more processors may be located inside and / or locally of the device. In this regard, a given circuit or its components may be set locally (e.g., as part of a local server, a local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud-based server). To this end, a "circuit" as described herein may include components distributed in one or more locations. The present disclosure contemplates methods, systems, and program products on any machine-readable medium for implementing various operations. The embodiments of the present disclosure may be implemented using existing computer processors, or by a dedicated computer processor of an appropriate system incorporated for this purpose or another purpose, or by a hard-wired system. The embodiments within the scope of the present disclosure include program products, which include machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor.By way of example, such machine-readable media may include RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of machine-executable instructions or data structures and can be accessed by a general-purpose or special-purpose computer or other machine with a processor. Combinations of the foregoing are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data that cause a general-purpose computer, a special-purpose computer, or a special-purpose processing machine to perform a specific function or group of functions.

Claims

1. A wound treatment system, comprising: a dressing capable of sealing over a wound and defining a wound space between the dressing and the wound; a tube coupled to the dressing and capable of fluid communication with the wound space; a canister capable of fluid communication with the tube, wherein the canister, the tube, and the dressing define a sealed space including the wound space; and a treatment unit coupled to the canister and comprising: a pneumatic pump capable of being in fluid communication with the sealed space; a sensor configured to measure a pressure in the sealed space; a valve positioned between the sealed space and the surrounding environment and controllable between an open position and a closed position; and A control circuit configured to determine the volume of the wound space by performing the following steps: controlling the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space; controlling the valve to repeatedly alternate between the open position and the closed position to achieve a controlled air flow rate through the valve; receiving a measurement of the pressure in the sealed space from the sensor; and A volume of the wound space is determined based on the measurement of the pressure.

2. A wound treatment system according to claim 1, wherein the controlled airflow rate is less than a restrictive rate of a filter positioned between the valve and the canister.

3. The wound treatment system of claim 1 , wherein the valve comprises a solenoid valve; and Wherein the control circuit is configured to control the valve by providing a voltage pattern to the solenoid valve to repeatedly alternate between the open position and the closed position.

4. A wound treatment system according to claim 3, wherein the voltage pattern comprises a step function that repeatedly steps between approximately zero voltage and a non-zero voltage.

5. A wound treatment system according to claim 4, wherein the voltage pattern is maintained at the non-zero voltage for a maximum continuous duration of no more than 500 milliseconds.

6. A wound treatment system according to claim 5, wherein the voltage pattern includes a repeating pattern of approximately 400 milliseconds at a non-zero voltage, approximately 100 milliseconds at approximately zero voltage, approximately 400 milliseconds at the non-zero voltage, and approximately 100 milliseconds at approximately zero voltage.

7. A wound treatment system according to claim 6, wherein the voltage pattern includes a first set of two cycles of the repeating pattern, approximately one second at approximately zero voltage, and a second set of two cycles of the repeating pattern.

8. The wound treatment system of claim 3, wherein the voltage pattern causes the solenoid valve to alternate between the open position and the closed position with a period of approximately 500 milliseconds.

9. The wound treatment system of claim 1 , wherein the control circuit is further configured to: customizing a customized wound therapy based on the volume of the wound space; and The therapy unit is controlled to provide the customized wound therapy.

10. A wound treatment system according to claim 9, wherein the customized wound treatment comprises infusion therapy.

11. The wound treatment system of claim 10, wherein the control circuit is configured to customize the infusion therapy by determining an amount of infusion fluid supplied to the wound space based on the volume of the wound space.

12. The wound treatment system of claim 11, comprising: a drip tube coupled to the dressing and capable of fluid communication with the wound space; a drip fluid source capable of being in fluid communication with the drip tube; and A drip pump is controllable by the control circuit to provide the amount of the drip fluid from the source to the wound space.

13. A wound treatment system, comprising: a dressing capable of sealing over a wound and defining a wound space between the dressing and the wound; a first tube coupled to the dressing and capable of fluid communication with the wound space; a canister capable of fluid communication with the first tube, wherein the canister, the first tube, and the dressing define a sealed space including the wound space; a pneumatic pump capable of being in fluid communication with the sealed space; a sensor configured to measure a pressure in the sealed space; a solenoid valve controllable between an open position and a closed position, the solenoid valve being configured to allow air to flow from the surrounding environment to the sealed space in the open position and to prevent air from flowing from the surrounding environment to the sealed space in the closed position; a drip tube coupled to the dressing and capable of fluid communication with the wound space and a source of instillation fluid; a drip pump coupled to the drip tube and controllable to supply an amount of drip fluid to the wound space; and A control circuit configured to determine the volume of the wound space by performing the following steps: controlling the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space; providing a voltage pattern to the solenoid valve, the voltage pattern causing the solenoid valve to repeatedly alternate between the open position and the closed position; receiving a measurement of the pressure from the sensor; as well as determining a volume of the wound space based on the measurement of the pressure; The control circuit is further configured to: determining the amount of the instillation fluid based on the volume of the wound space; as well as The infusion pump is controlled to supply the amount of the infusion fluid to the wound space.

14. The wound treatment system of claim 13, wherein alternating the solenoid valve between the open position and the closed position allows a controlled airflow rate from the ambient environment to the sealed space through the solenoid valve.

15. The wound treatment system of claim 14, wherein the solenoid valve is positioned to allow the air to enter one or more outer lumens of the first tube.

16. The wound treatment system of claim 15, comprising a filter positioned between the solenoid valve and the one or more outer lumens; and wherein alternating the solenoid valve between the open position and the closed position allows a controlled rate of gas flow from the ambient environment to the one or more outer lumens through the solenoid valve; Wherein the controlled airflow rate is less than the restriction rate of the filter.

17. A wound treatment system according to claim 13, wherein the infusion pump, the pneumatic pump and the control circuit are housed within a treatment unit.

18. The wound treatment system of claim 17, wherein the solenoid valve is positioned within the treatment unit.

19. The wound treatment system of claim 17, wherein the solenoid valve is positioned outside the treatment unit and coupled to the first tube.

20. A treatment unit, comprising: a pneumatic pump capable of being in fluid communication with the sealed space; a sensor configured to measure a pressure in the sealed space; a valve positioned between the sealed space and the surrounding environment and controllable between an open position and a closed position; and A control circuit is configured to determine the volume of the sealed space by performing the following steps: controlling the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space; controlling the valve to repeatedly alternate between the open position and the closed position to achieve a controlled air flow rate through the valve; receiving a measurement of the pressure in the sealed space from the sensor; as well as A volume of the sealed space is determined based on the measurements of the pressure and the controlled airflow rate.

21. The treatment unit of claim 20, wherein the control circuit is configured to achieve the controlled gas flow rate through the valve by controlling the valve to the open position for a maximum continuous duration of no more than 500 milliseconds.

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