Wound therapy system with wound volume estimation

Abstract

To provide a wound therapy system configured to estimate a volume of a wound.SOLUTION: A wound therapy system comprises: a negative pressure circuit; a pump; a pressure sensor; and a controller. The negative pressure circuit applies a negative pressure to a wound. The pump is fluidly coupled to the negative pressure circuit, and generates the negative pressure at the wound or within the negative pressure circuit. The pressure sensor measures the negative pressure within the negative pressure circuit or the wound. The controller executes a test procedure including; a first drawdown period; a leak rate determination period; a vent period; and a second drawdown period. The controller is configured to receive one or more pressure measurement values of the pressure sensor, over the leak rate determination period, and monitors lapsed time over the second drawdown period for determining a drawdown parameter, and on the basis of the leak rate parameter and the drawdown parameter, estimates a volume of the wound.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to wound therapy systems, and more particularly to wound therapy systems configured to estimate wound volume. [Background technology]

[0002] Negative pressure wound therapy (NPWT) is a type of wound therapy that involves applying negative pressure to a wound site to promote wound healing. Some wound treatment systems use pneumatic pumps to apply negative pressure to the wound to generate the necessary negative pressure and flow. Recent advances in NPWT wound healing involve applying topical fluids to the wound to work in conjunction with NPWT. However, determining the appropriate volume of instilled fluid to deliver to the wound can be difficult. Additionally, accurately monitoring and tracking the progress of wound healing over time can be challenging. Summary of the Invention

[0003] One implementation of the present disclosure is a wound therapy system according to some embodiments. In some embodiments, the wound therapy system includes a negative pressure circuit, a pump, a pressure sensor, and a controller. In some embodiments, the negative pressure circuit is configured to apply negative pressure to the wound. In some embodiments, the pump is fluidly coupled to the negative pressure circuit and configured to generate negative pressure at the wound or within the negative pressure circuit. In some embodiments, the pressure sensor is configured to measure the negative pressure in the negative pressure circuit or at the wound. In some embodiments, the controller is configured to execute a test procedure including a first drawdown period, a leak rate determination period, a vent period, and a second drawdown period. In some embodiments, the controller is configured to receive one or more pressure measurements from the pressure sensor over the leak rate determination period to determine a leak rate parameter. In some embodiments, the controller is configured to monitor the elapsed time of the second drawdown period to determine the drawdown parameter. In some embodiments, the controller is configured to estimate a wound volume based on the leak rate parameter and the drawdown parameter.

[0004] In some embodiments, the first lowering period of the test procedure includes operating a pump to achieve a predetermined negative pressure in the negative pressure circuit.

[0005] In some embodiments, the leak rate determination portion of the test procedure includes maintaining a predetermined negative pressure for a predetermined duration and receiving a pressure measurement from a pressure sensor during the predetermined duration.

[0006] In some embodiments, the leak rate parameter is the change in pressure in the negative pressure circuit over a leak rate determination period.

[0007] In some embodiments, the leak rate parameter is the change in pressure with respect to time over at least a portion of the leak rate determination period.

[0008] In some embodiments, the venting period of the test procedure includes opening a valve in the negative pressure circuit to return the negative pressure circuit to atmospheric pressure.

[0009] In some embodiments, the second drawdown period of the test procedure includes operating a pump to generate negative pressure in the negative pressure circuit at a predetermined rate.

[0010] In some embodiments, the drawdown parameter is the amount of time the pump operates at a given speed to achieve a given pressure value in the negative pressure circuit.

[0011] In some embodiments, the controller is further configured to estimate the volume of the wound by inputting the drawdown parameter and the leak rate parameter into a model relating the volume of the wound to the drawdown parameter and the leak rate parameter.

[0012] In some embodiments, the model is determined by performing a test procedure for known values ​​of wound volume and determining the model based on the known values ​​of wound volume and the leak rate parameters and drawdown parameters associated with each known value of wound volume.

[0013] Another implementation of the present disclosure is a method for determining wound volume according to some embodiments. In some embodiments, the method includes providing a negative pressure circuit configured to apply negative pressure to the wound. In some embodiments, the method includes providing a pump fluidly coupled to the negative pressure circuit and configured to generate negative pressure at or within the negative pressure circuit. In some embodiments, the method includes providing a pressure sensor configured to measure negative pressure in the negative pressure circuit or at the wound. In some embodiments, the method includes performing a test procedure for a known value of wound volume. In some embodiments, the test procedure includes performing a first drawdown for a first drawdown period, performing a leak rate determination for a leak rate determination period, evacuating the negative pressure circuit, and performing a second drawdown for a second drawdown period. In some embodiments, the method includes receiving one or more pressure measurements of the pressure sensor over the leak rate determination period to determine a leak rate parameter. In some embodiments, the method includes monitoring the elapsed time of the second drawdown period to determine the drawdown parameter. In some embodiments, the method includes generating a model based on known values ​​of wound volume, a leak rate parameter, and a drawdown parameter. In some embodiments, the model relates wound volume to the leak rate parameter and the drawdown parameter. In some embodiments, the method includes re-performing the steps of performing the test procedure, receiving one or more pressure measurements, and monitoring elapsed time to determine the leak rate parameter and the drawdown parameter for an unknown value of wound volume. In some embodiments, the method further includes estimating the unknown value of wound volume by inputting the leak rate parameter and the drawdown parameter associated with the unknown value of wound volume into the model.

[0014] In some embodiments, the first drawdown includes operating a pump to achieve a predetermined negative pressure in the negative pressure circuit. In some embodiments, the leak rate determination includes maintaining the predetermined negative pressure for a predetermined duration and receiving a pressure measurement from a pressure sensor during the predetermined duration.

[0015] In some embodiments, the leak rate parameter is the change in pressure in the negative pressure circuit over a leak rate determination period.

[0016] In some embodiments, the leak rate parameter is the rate of change of pressure in the negative pressure circuit with respect to time over at least a portion of the leak rate determination period.

[0017] In some embodiments, venting the negative pressure circuit includes opening a valve in the negative pressure circuit to return the negative pressure circuit to atmospheric pressure.

[0018] In some embodiments, the second drawdown comprises operating a pump to generate negative pressure in the negative pressure circuit at a predetermined drawdown rate.

[0019] In some embodiments, the drawdown parameter is the time that the pump operates at a given drawdown rate to achieve a given pressure value in the negative pressure circuit.

[0020] In some embodiments, the model is determined by performing a test procedure for multiple known values ​​of wound volume to determine multiple values ​​of the leak rate parameter and the drawdown parameter, hi some embodiments, the model is determined by performing a regression on values ​​of wound volume and values ​​of the leak rate parameter and the drawdown parameter.

[0021] In some embodiments, the model is a look-up table relating leak rate and drawdown parameters to wound volume.

[0022] Another implementation of the present disclosure is a wound therapy device according to some embodiments. In some embodiments, the wound therapy device includes a pump fluidly coupled to a negative pressure circuit. In some embodiments, the pump is configured to generate negative pressure at the wound or within the negative pressure circuit. In some embodiments, the negative pressure circuit is configured to apply negative pressure to the wound. In some embodiments, the wound therapy device includes a pressure sensor configured to measure negative pressure in the negative pressure circuit or at the wound, and a controller. In some embodiments, the controller is configured to operate the pump to generate negative pressure in the negative pressure circuit, receive one or more pressure measurements from the pressure sensor over a predetermined period of time, determine a leak rate based on the received one or more pressure measurements from the pressure sensor over the predetermined period of time, vent the negative pressure circuit to atmospheric pressure, and operate the determining pump to reduce the pressure in the negative pressure circuit at a predetermined rate. In some embodiments, the controller is configured to monitor the elapsed time that the pump operates at the predetermined rate until a predetermined pressure is achieved in the negative pressure circuit. In some embodiments, the controller is configured to estimate a volume of the wound based on the leak rate and the elapsed time.

[0023] Those skilled in the art will appreciate that the Summary is illustrative only and is not intended to be limiting in any way. Other aspects, inventive features, and advantages of the devices and / or processes described herein, as defined solely by the claims, will become apparent in the detailed description set forth herein and taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a block diagram of a wound therapy system including a therapy device coupled to a wound dressing via a tube, according to an exemplary embodiment.

[0025] [Figure 2]2 is a block diagram illustrating the therapy device of FIG. 1 in greater detail when the therapy device operates to draw a vacuum in the negative pressure circuit, according to an exemplary embodiment.

[0026] [Figure 3A] 2 is a block diagram illustrating the therapy device of FIG. 1 in greater detail when the therapy device operates to vent the negative pressure circuit, according to an exemplary embodiment.

[0027] [Figure 3B] 2 is a block diagram illustrating the therapy device of FIG. 1 in greater detail when the therapy device uses an orifice to vent the negative pressure circuit, according to an exemplary embodiment.

[0028] [Figure 4] 2 is a block diagram illustrating the therapy device of FIG. 1 in greater detail when the therapy device is operating to deliver intravenous fluid to a wound dressing and / or wound, according to an exemplary embodiment.

[0029] [Figure 5] 2 is a block diagram illustrating the controller of the therapy device of FIG. 1 in more detail, according to an exemplary embodiment.

[0030] [Figure 6] 1 is a graph illustrating a test procedure for determining leak rate and drawdown time parameters according to an exemplary embodiment. [Figure 7] 1 is a graph illustrating a test procedure for determining leak rate and drawdown time parameters according to an exemplary embodiment.

[0031] [Figure 8] 2 is a diagram of the wound therapy system of FIG. 1 according to an exemplary embodiment.

[0032] [Figure 9]1 is a table having top headers of various drawdown time parameter values, side headers of various leak rate parameters, and wound volume values ​​corresponding to various combinations of drawdown time and leak rate parameters, according to an exemplary embodiment.

[0033] [Figure 10] 1 is a graph showing wound volume and instilled fluid volume over time according to an exemplary embodiment.

[0034] [Figure 11] 10 is a flowchart of a process for determining an infusion fluid volume to deliver to a wound based on an estimated wound volume, according to an exemplary embodiment.

[0035] [Figure 12A] 10 is a flowchart of a process for generating a model relating drawdown time and leak rate parameters to wound volume according to an exemplary embodiment. [Figure 12B] 10 is a flowchart of a process for generating a model relating drawdown time and leak rate parameters to wound volume according to an exemplary embodiment.

[0036] [Figure 13] 10 is a flowchart of a process for determining wound volume and infusion volume according to an exemplary embodiment.

[0037] [Figure 14] 2 is a flowchart of a process for operating the therapy device of FIG. 1 according to an exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0038] overview Referring to the figures, a wound therapy system and its components for infusion and removal of fluids are shown according to various exemplary embodiments. The wound therapy system may include a therapy device and a wound dressing. The therapy device may include an infusion fluid canister, a removal fluid canister, a valve, a pneumatic pump, an infusion pump, and a controller. The wound dressing may be applied to the patient's skin surrounding the wound. The therapy device may be configured to provide negative pressure wound therapy (NPWT) by delivering infusion fluid to the wound and maintaining negative pressure at the wound. The wound therapy device, wound dressing, and wound components form a negative pressure circuit.

[0039] The controller can estimate the wound volume based on the leakage rate of the wound dressing and the time it takes the air pump to achieve a predetermined negative pressure. The controller can cause the therapy device to perform a test procedure (e.g., a pressure test procedure) to determine the leakage rate of the wound dressing and the time it takes the air pump to achieve a predetermined negative pressure. The leakage rate of the wound dressing and the time it takes the air pump to achieve a predetermined negative pressure at the wound are observed parameters. For example, the controller can apply the observed parameters as inputs to a model defining the relationship between the observed parameters and the volume of the negative pressure circuit and / or the volume of the wound. The model can include a polynomial approximation model, a neural network model, or any other model relating the observed parameters to the volume of the negative pressure circuit and / or the volume of the wound. In some embodiments, the model is a pre-existing model stored in the controller by the manufacturer of the therapy device. In other embodiments, the controller can generate the model on-site by performing a training procedure.

[0040] The training procedure may be the same as the pressure testing procedure, except that the therapy device is connected to a training circuit having a known volume. For example, a wound dressing may be applied to a test device having a known volume rather than to the patient's skin surrounding the wound. The controller may run the training procedure with different training circuits having different known volumes and observe the parameters of each training circuit (i.e., leak rate and time to achieve a predetermined negative pressure). Each known volume may result in a different observed parameter. The controller may then associate the known volume of each training circuit with the corresponding parameter. In some embodiments, the controller uses the observed parameters and the known volume of the training circuit to generate a model defining the relationship between the observed parameters and the volume of the training circuit. This model may be stored in the therapy device and used to estimate wound volume as described above.

[0041] In some embodiments, the controller is configured to perform a pressure test procedure, observe parameters, and estimate wound volume at multiple times during wound treatment. The controller can then determine healing progress based on changes in wound volume during wound treatment. In some embodiments, the controller is configured to determine a volume of infusion fluid to deliver to the wound based on the estimated wound volume. The volume of infusion fluid to deliver may be a predetermined percentage of the wound volume (e.g., 20%, 50%, 80%, etc.). The controller can then operate the infusion pump to deliver the determined volume of infusion fluid to the wound. These and other features of the wound therapy system are described in detail below.

[0042] Wound Therapy System 1-4, a negative pressure wound therapy (NPWT) system 100 is shown according to an exemplary embodiment. The NPWT system 100 is shown to include a therapy device 102 fluidly connected to a wound dressing 112 via tubing 108 and 110. The wound dressing 112 may be adhered or sealed to the patient's skin 116 surrounding a wound 114. Some examples of wound dressings 112 that can be used in combination with the NPWT system 100 are described in detail in U.S. Pat. No. 7,651,484, granted January 26, 2010; U.S. Pat. No. 8,394,081, granted March 12, 2013; and U.S. patent application Ser. No. 14 / 087,418, filed November 22, 2013. The entire disclosures of each of these patents and patent applications are incorporated herein by reference.

[0043] The therapy device 102 can be configured to provide negative pressure wound therapy by reducing pressure at the wound 114. The therapy device 102 can draw a vacuum (relative to atmospheric pressure) at the wound 114 by removing wound exudate, air, and other fluids from the wound 114. Wound exudate may include fluids that are filtered through the patient's circulatory system and enter the lesion or inflamed area. For example, wound exudate may include water and dissolved solutes, such as blood, plasma proteins, white blood cells, platelets, and red blood cells. Other fluids removed from the wound 114 may include infusion fluid 105 previously delivered to the wound 114. Infusion fluid 105 may include, for example, irrigation fluid, predetermined fluid, medicinal fluid, antibiotic fluid, or any other type of fluid that may be delivered to the wound 114 during wound treatment. The infusion fluid 105 may be held in an infusion fluid canister 104 and controllably dispensed into the wound 114 via infusion fluid tubing 108. In some embodiments, the infusion fluid canister 104 is removable from the therapy device 102 to allow the canister 106 to be refilled and replaced as needed.

[0044] Fluid 107 removed from the wound 114 passes through removal fluid tube 110 and is collected in removal fluid canister 106. The removal fluid canister 106 may be a component of therapy device 102 configured to collect wound exudate and other fluids 107 removed from the wound 114. In some embodiments, the removal fluid canister 106 is removable from therapy device 102 to allow the canister 106 to be emptied and replaced as needed. A lower portion of canister 106 may be filled with wound exudate and other fluids 107 removed from the wound 114, and an upper portion of canister 106 may be filled with air. The therapy device 102 may be configured to draw a vacuum in canister 106 by pumping air from canister 106. The reduced pressure in the canister 106 can be transferred via the tube 110 to the wound dressing 112 and the wound 114 so that the wound dressing 112 and the wound 114 are maintained at the same pressure as the canister 106 .

[0045] 2-4, a block diagram illustrating therapy device 102 in greater detail is shown in accordance with an exemplary embodiment. The therapy device 102 is shown to include an air pressure pump 120, an infusion pump 122, a valve 132, a filter 128, and a controller 118. Air pressure pump 120 may be fluidly coupled to removal fluid canister 106 (e.g., via conduit 136) and may be configured to pump air from canister 106, thereby creating a vacuum within canister 106. In some embodiments, air pressure pump 120 is configured to operate in both a forward and reverse direction. For example, air pressure pump 120 may operate in a forward direction to pump air out of canister 106, reducing the pressure within canister 106. Air pressure pump 120 may operate in a reverse direction to pump air into canister 106, increasing the pressure within canister 106. The pneumatic pump 120 may be controlled by a controller 118, which is described in more detail below.

[0046] Similarly, infusion pump 122 may be fluidly connected to infusion fluid canister 104 via tubing 109 and to wound dressing 112 via tubing 108. Infusion pump 122 may be operated to deliver infusion fluid 105 to wound dressing 112 and wound 114 by pumping infusion fluid 105 through tubing 109 and tubing 108, as shown in Figure 4. Infusion pump 122 may be controlled by controller 118, which is described in more detail below.

[0047] The filter 128 can be positioned between the removal fluid canister 106 and the pneumatic pump 120 (e.g., along the conduit 136) so that air pumped from the canister 106 passes through the filter 128. The filter 128 can be configured to prevent liquids 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 so that aqueous and / or oily liquids bead on the surface of the filter 128. The pneumatic pump 120 can be configured to allow sufficient airflow through the filter 128 (e.g., so that the pressure drop does not substantially interfere with the application of negative pressure from the therapy device 102 to the wound 114) so ​​that the pressure drop through the filter 128 is insubstantial.

[0048] In some embodiments, therapy device 102 controllably evacuates the negative pressure circuit by operating valve 132, as shown in FIG. 3A . Valve 132 can be fluidly connected to pump 120 and filter 128 via conduit 136. In some embodiments, valve 132 is configured to control airflow between conduit 136 and the environment surrounding therapy device 102. For example, valve 132 can be open to allow airflow into conduit 136 via vent 134 and conduit 138, and closed to prevent airflow into conduit 136 via vent 134 and conduit 138. Valve 132 can be controlled by controller 118, which is described in more detail below. When valve 132 is closed, air pressure pump 120 can draw a vacuum in the negative pressure circuit by forcing airflow in a first direction through filter 128, as shown in FIG. 2 . The negative pressure circuit can include any component of system 100 (e.g., conduit 136, removal fluid canister 106, tubing 110, wound dressing 112, and / or wound 114) that can be maintained at a negative pressure when performing negative pressure wound therapy. For example, the negative pressure circuit can include conduit 136, removal fluid canister 106, tubing 110, wound dressing 112, and / or wound 114. When valve 132 is open, airflow from the environment surrounding therapy device 102 can enter conduit 136 via vent 134 and conduit 138 to fill the vacuum in the negative pressure circuit. Airflow from conduit 136 to canister 106 and other volumes in the negative pressure circuit can pass through filter 128 in a second direction opposite the first direction, as shown in FIG. 3A .

[0049] In some embodiments, therapy device 102 vents the negative pressure circuit through orifice 158, as shown in FIG. 3B . Orifice 158 may be a small opening in conduit 136 or any other component of the negative pressure circuit (e.g., removal fluid canister 106, tubing 110, tubing 111, wound dressing 112, etc.) that allows air to leak into the negative pressure circuit at a known rate. In some embodiments, therapy device 102 vents the negative pressure circuit through orifice 158 rather than operating valve 132. Valve 132 may be omitted from therapy device 102 for any embodiment that includes orifice 158. The rate at which air leaks into the negative pressure circuit through orifice 158 may be substantially constant or may vary as a function of negative pressure, depending on the shape of orifice 158. In embodiments in which the leak rate through the orifice 158 is variable, the controller 118 can use a stored relationship between negative pressure and leak rate to calculate the leak rate through the orifice 158 based on the measured negative pressure. Whether the leak rate through the orifice 158 is substantially constant or variable, the leakage of air into the negative pressure circuit through the orifice 158 can be used to generate a pressure decay curve for use in estimating the volume 160 (see FIG. 8) of the wound 114.

[0050] In some embodiments, therapy device 102 includes various sensors. For example, therapy device 102 is shown including pressure sensor 130 configured to measure pressure within canister 106 and / or pressure at wound dressing 112 or wound 114. In some embodiments, therapy device 102 includes pressure sensor 113 configured to measure pressure within tubing 111. Tube 111 may be connected to wound dressing 112 and may be dedicated to measuring pressure at wound dressing 112 or wound 114 without having a secondary function such as carrying IV fluid 105 or wound exudate. In various embodiments, tubes 108, 110, and 111 may be physically separate tubes or may be separate lumens within a single tube connecting therapy device 102 to wound dressing 112. Thus, tube 110 may be described as a negative pressure lumen that functions to apply negative pressure to wound dressing 112 or wound 114, while tube 111 may be described as a sensing lumen configured to sense pressure at wound dressing 112 or wound 114. Pressure sensors 130 and 113, in various embodiments, may be located within therapy device 102, positioned anywhere along tubes 108, 110, and 111, or may be located in wound dressing 112. Pressure measurements recorded by pressure sensors 130 and / or 113 may be communicated to controller 118, which uses the pressure measurements as inputs to various pressure testing and control operations performed by controller 118 (described in more detail with reference to FIGS. 5-14).

[0051] The controller 118 can be configured to operate the air pressure pump 120, the infusion pump 122, the valve 132, and / or other controllable components of the therapy device 102. In some embodiments, the controller 118 performs a pressure test procedure by applying a pressure stimulus to the negative pressure circuit. For example, the controller 118 can instruct the air pressure pump 120 to operate with the valve 132 closed to establish negative pressure in the negative pressure circuit. Once negative pressure is established, the controller 118 can deactivate the air pressure pump 120. The controller 118 can cause the valve 132 to open for a predetermined time and then close after the predetermined time has elapsed. The controller 118 can use pressure measurements recorded by the pressure sensors 130 and / or 113 to observe the dynamic pressure response of the negative pressure circuit to the pressure stimulus. The dynamic pressure response can be measured, for example, by a drawdown time parameter α time and the leak rate parameter α leak The temperature may be characterized by a variety of parameters, including:

[0052] The controller 118 can estimate the volume 160 of the wound 114 based on the observed dynamic pressure response. For example, the controller 118 can apply the observed parameters as inputs to a model that defines a relationship between the observed parameters and the volume of the negative pressure circuit and / or the volume 160 of the wound 114. The model can include a polynomial approximation model, a neural network model, or any other model that relates the observed parameters to the volume of the negative pressure circuit and / or the volume 160 of the wound 114. In some embodiments, the model is a pre-existing model stored in the controller 118 by the manufacturer of the therapy device 102. In other embodiments, the controller 118 can generate the model on-site by performing a training procedure.

[0053] The training procedure may be the same as the pressure testing procedure, except that the therapy device 102 is connected to a training circuit having a known volume. For example, the wound dressing 112 may be applied to a test device having a known volume rather than to the patient's skin 116 surrounding the wound 114. The controller 118 may apply pressure stimuli to various training circuits having different known volumes and observe the dynamic pressure response of each training circuit. Each known volume may result in a different dynamic pressure response to the pressure stimuli. The controller 118 may then associate the known volume of each training circuit with the corresponding dynamic pressure response. In some embodiments, the controller 118 uses the dynamic pressure responses of the training circuits to generate a model that defines the relationship between observed parameters of the dynamic pressure response (e.g., purge depth, rebound, delta, leak rate, etc.) and the volume of the training circuit. This model may then be stored in the controller 118 and used to estimate the volume of the wound 114 as described above. In some embodiments, the controller 118 may use a drawdown time parameter α time and the leak rate parameter α leak and determine one or more sets of values ​​for the drawdown time parameter α time and the leak rate parameter α time Each set of values ​​corresponds to a known volume 160. In some embodiments, the controller 118 uses one or more sets of values ​​to generate the model.

[0054] In some embodiments, the controller 118 is configured to perform a pressure test procedure, observe the dynamic pressure response, and estimate the volume 160 of the wound 114 at multiple times during wound treatment. The controller 118 can then determine healing progress based on the change in the volume 160 of the wound 114 during wound treatment. In some embodiments, the controller 118 is configured to determine a volume of infusion fluid 105 to deliver to the wound 114 based on the estimated wound volume 160. The volume of infusion fluid 105 to deliver may be a predetermined percentage (e.g., 20%, 50%, 80%, etc.) of the volume 160 of the wound 114. The controller 118 can then operate the infusion pump 122 to deliver the determined volume of infusion fluid 105 to the wound 114. These and other features of the controller 118 are described in more detail with reference to FIGS. 5-14.

[0055] In some embodiments, therapy device 102 includes a user interface 126. User interface 126 may include one or more buttons, dials, sliders, keys, or other input devices configured to receive input from a user. 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. In some embodiments, pressure measurements recorded by pressure sensors 130 and / or 113 are presented to the user via user interface 126. User interface 126 may also display alerts generated by controller 118. For example, controller 118 may generate a "canister missing" alert if canister 106 is not detected.

[0056] In some embodiments, the therapy device 102 includes a data communication interface 124 (e.g., a USB port, a wireless transceiver, etc.) configured to transmit and receive 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 wire terminal, etc.) for directing data communication with an external system or device. In various embodiments, communication may be direct (e.g., local wired or local 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, as well as a port for transmitting and receiving data over an Ethernet-based communication link or network. In another example, the communication interface 124 may include a Wi-Fi transceiver for communicating over a wireless communication network or a transceiver for cellular or mobile phone communication.

[0057] 8, the wound 114 is shown in more detail according to some embodiments. In some embodiments, when the pressure within the wound 114 is reduced due to operation of the air pressure pump 120, one or more leaks are formed. For example, air may enter the volume 160 of the wound 114 around the corners of the wound dressing 112. If the tubes 110, 108, 111 are fluidly connected to the volume 160 via connectors 162, 164, 166, respectively, leaks may occur at the connectors 162, 164, 166. In some embodiments, the pressure within the interior volume 160 of the wound 114 (e.g., p1) may be greater than atmospheric pressure p atm (i.e., the pressure of the air outside the wound dressing 112), the pressure difference Δp diff =p atm In some embodiments, a pressure difference Δp diffThis allows air to enter volume 160 and travel up tube 110 through any leaks in wound dressing 112 and connectors 162-166. Leaks may also form anywhere else between the wound dressing 112 interface and the patient's skin 116. In some embodiments, air leakage into volume 160 of the wound 114 correlates with an increase in the time required for air pressure pump 120 to achieve negative pressure.

[0058] controller 5, a block diagram illustrating controller 118 in more detail is shown, according to an exemplary embodiment. Controller 118 is shown to include processing circuitry 140, which includes a processor 142 and memory 144. Processor 142 may be a general-purpose or application-specific processor, an application-specific integrated circuit (ASIC), one or more field-programmable gate arrays (FPGAs), a group of processing components, or other suitable processing components. Processor 142 is configured to execute computer code or instructions stored in memory 144 or received from other computer-readable media (e.g., CD-ROM, network storage, remote server, etc.).

[0059] Memory 144 may include one or more devices (e.g., memory units, memory devices, storage devices, etc.) for storing data and / or computer code for completing and / or facilitating the various processes described in this disclosure. Memory 144 may include random access memory (RAM), read-only memory (ROM), hard drive storage, temporary storage, non-volatile memory, flash memory, optical memory, or any other suitable memory for storing software objects and / or computer instructions. Memory 144 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in this disclosure. Memory 144 may be communicatively coupled to processor 142 via processing circuitry 140 and may include computer code for executing (e.g., by processor 142) one or more processes described herein. When processor 142 executes instructions stored in memory 144, processor 142 generally configures controller 118 (and more specifically processing circuitry 140) to complete such activities.

[0060] The controller 118 is shown to include a pump control 146 and a valve control 150. The pump control 146 can be configured to operate the pumps 120 and 122 by generating and providing control signals to the pumps 120-122. The control signals provided to the pumps 120-122 can activate, deactivate, or achieve variable displacement or speed (e.g., operate at half speed, operate at full speed, etc.). Similarly, the valve control 150 can be configured to operate the valve 132 by generating and providing a control signal to the valve 132. The control signal provided to the valve 132 can cause the valve 132 to open, close, or achieve a specified intermediate position (e.g., one-third open, half open, etc.). In some embodiments, the pump control unit 146 and the valve control unit 150 are used by other components of the controller 118 (e.g., the test procedure control unit 148, the wound volume estimator unit 156, etc.) to operate the pumps 120-122 and the valves 132 in carrying out the processes described herein.

[0061] In some embodiments, pump controller 146 uses input from a canister sensor configured to detect whether removal fluid canister 106 is present. Pump controller 146 can be configured to activate pneumatic pump 120 only if removal fluid canister 106 is present. For example, pump controller 146 can check whether canister 106 is present and can activate pneumatic pump 120 in response to determining that canister 106 is present. However, if canister 106 is not present, pump controller 146 may prevent pneumatic pump 120 from activating. Similarly, pump controller 146 can be configured to activate infusion pump 122 only if removal fluid canister 104 is present. For example, pump controller 146 can check whether canister 104 is present and can activate infusion pump 122 in response to determining that canister 104 is present. However, if canister 104 is not present, pump controller 146 may prevent infusion pump 122 from activating.

[0062] The controller 118 is shown to include a pressure monitoring unit 152. The pressure monitoring unit 152 can be configured to monitor the pressure within the removal fluid canister 106 and / or the pressure within the wound dressing 112 or wound 114 using feedback from the pressure sensors 130 and / or 113. For example, the pressure sensors 130 and / or 113 may provide pressure measurements to the pressure monitoring unit 152. The pressure monitoring unit 152 can use the pressure measurements to determine the pressure within the canister 106 and / or the pressure within the wound dressing 112 or wound 114 in real time. The pressure monitoring unit 152 can provide pressure values ​​to the model generator 154, the pump control 146, the test procedure control 148, and / or the valve control 150 for use as input to the control processes performed by these components.

[0063] 5, the controller 118 is shown to include a test procedure control 148. The test procedure control 148 can be configured to execute a pressure test procedure to interrogate and observe a pressure dynamic response or leak rate. When the therapy device 102 is connected to a wound dressing 112 applied to the patient's skin 116 on the wound 114, the test procedure control 148 can observe the dynamic pressure response and leak rate of the negative pressure circuit including the conduit 136, the removal fluid canister 106, the tubing 110, the wound dressing 112, and / or the wound 114 (which may have an unknown volume). When the therapy device 102 is connected to a wound dressing 112 applied to a training device having a known volume, the test procedure control 148 can observe the dynamic pressure response of the training circuit including the conduit 136, the removal fluid canister 106, the tubing 110, the wound dressing 112, and / or the training device.

[0064] Test Procedure 6, a graph 600 illustrates a test procedure that the controller 118 (e.g., the test procedure control 148) may be configured to execute, according to some embodiments. In some embodiments, the controller 118 may adjust the leak rate parameter α leak and the drawdown time parameter α time The system is configured to perform the test procedure shown in graph 600 to determine:

[0065] Graph 600 includes a series 602 illustrating the relationship between negative pressure (Y-axis) and time (X-axis) over a test procedure, according to some embodiments. In some embodiments, the test procedure includes a first drawdown period 604, a leak rate determination period 606, a vent period 608, and a second drawdown period 610. In some embodiments, first drawdown period 604 occurs between time t0 and time t1. In some embodiments, leak rate determination period 606 occurs between time t1 and time t2. In some embodiments, vent period 608 occurs between time t2 and time t3. In some embodiments, second drawdown period 610 occurs between time t3 and time t4.

[0066] During the first drawdown period 604, the controller 118 can send a control signal to the valve 132 to transition the valve 132 to a closed configuration so that air cannot pass from the conduit 138 to the vent 134. In some embodiments, the test protocol control 148 sends a command to the valve control 150 to transition the valve 132 to a closed configuration for the first drawdown period 604. In some embodiments, after the valve 132 transitions to the closed configuration, the test protocol control 148 sends a control signal to the pump control 146 to draw down (e.g., generate negative pressure) at the wound 114. In some embodiments, the test protocol control 148 controls the drawdown rate (i.e., TIFF2025160174000002.tif9128) to the pump controller 146. The pump controller 146 is configured to send a control signal to the air pressure pump 120 to draw down the pressure in the wound 114 (e.g., generate negative pressure) according to a drawdown rate. In some embodiments, the pump controller 146 is configured to operate the air pressure pump 120 to draw down according to one or more predetermined drawdown rates. In some embodiments, the test sequence controller 148 is configured to send a command to the pump controller 146 to cause the air pressure pump 120 to draw down at a maximum rate for the first drawdown period 604. In some embodiments, the test sequence controller 148 sends a value of the manipulated variable u to the pump controller 146 to cause the air pressure pump 120 to draw down according to the predetermined drawdown rate. For example, the test sequence controller 148 may send to the pump controller 146 a binary value of the manipulated variable u (e.g., u=1 or u=0). For example, test procedure controller 148 may send to pump controller 146 a value of manipulated variable u1=1 indicating that pump controller 146 should draw down pneumatic pump 120 at a first predetermined drawdown rate. Similarly, test procedure controller 148 may send to pump controller 146 a value of manipulated variable u2=1 indicating that pump controller 146 should draw down pneumatic pump 120 at a second predetermined drawdown rate that is greater than the first predetermined drawdown rate. Test procedure controller 148 may send to pump controller 146 a 1xd vector of values ​​of manipulated variable u such as: You can also send TIFF2025160174000003.tif6128. where u1 is a binary value of the manipulated variable u that indicates whether the pump control 146 should cause the pneumatic pump 120 to draw down at a first drawdown rate, u2 is another value of the manipulated variable u that indicates whether the pump control 146 should cause the pneumatic pump 120 to draw down at a second drawdown rate, etc., and u dis the dth binary value of the manipulated variable u that indicates whether the pump control 146 should draw down the pneumatic pump 120 at the dth drawdown rate. For example, if d=4 and the pump control 146 can draw down the pneumatic pump 120 according to four predetermined drawdown rates, then the vector TIFF2025160174000004.tif6128 can have the following form: For example, u1=0, u2=0, u3=0, and u4=1, indicating that the pump controller 146 should cause the pneumatic pump 120 to draw down according to a fourth drawdown rate (i.e., u4=1). In some embodiments, the dth drawdown rate (e.g., fourth in this case) is the fastest drawdown rate, and the first drawdown rate is the slowest drawdown rate. In some embodiments, the test procedure controller 148 sends a command to the pump controller 146 to cause the pneumatic pump 120 to draw down at the fastest drawdown rate for the first drawdown period 604 (e.g., u d =1). The test sequence control 148 can also use a variable drawdown rate of the air pressure pump over the second drawdown period 610. In some embodiments, the drawdown time parameter α time is determined over the second drawdown period 610. In some embodiments, if the drawdown rate of the air pressure pump 120 over the second drawdown period 610 is fast, the volume estimate of the wound 114 will be less accurate but will be estimated faster. Similarly, if the drawdown rate of the air pressure pump 120 over the second drawdown period 610 is slower, the volume estimate of the wound 114 will be more accurate but will take longer to estimate. In some embodiments, the model generator 154 generates a model f for various predetermined drawdown rates for the second drawdown period 610, as described in more detail below. wound The method is configured to determine:

[0067] In some embodiments, the test sequence controller 148 uses a setpoint r as a target value for the negative pressure during the first drawdown period 604. For example, as shown in FIG. 6, during the first drawdown period 604, r=p1. In some embodiments, p1 is a low pressure (e.g., a large magnitude of negative pressure). In some embodiments, p1=200 mmHg. In some embodiments, p1 is a negative pressure value that allows monitoring for any leaks in the wound dressing 112 and / or connectors 162-166. In some embodiments, p1 is a target value for the negative pressure to be achieved in the wound 114 at the end of the first drawdown period 604. For example, as shown in FIG. 6, the negative pressure increases throughout the first drawdown period 604 until time t1, at which time p=p1.

[0068] In some embodiments, the test procedure controller 148 receives measurements of the pressure p at the wound 114 via the pressure monitor 152 and the pressure sensors 130 / 113. In some embodiments, the test procedure controller 148 receives the value of the pressure p at the wound 114 as the value of the performance variable y. In some embodiments, the test procedure controller 148 is configured to perform feedback control (e.g., PID control, PI control, etc.) to determine the value of the manipulated variable u. In some embodiments, the test procedure controller 148 monitors the value of the performance variable y in real time until the value of the performance variable y is substantially equal to a set value r (e.g., p1). In some embodiments, once the value of the performance variable y is substantially equal to the value of the set value r (e.g., p=p1), the test procedure controller 148 sends the value of the manipulated variable u to the pump controller 146, causing the pneumatic pump 120 to stop drawdown. For example, the test procedure controller 148 may initially send values ​​of the manipulated variable u, such as u=1, to the pump controller 146 until y=r. In some embodiments, when y=r, the test sequence controller 148 sends a value of the manipulated variable u, such as u=0, to the pump controller 146, which causes the pump controller 146 to stop drawing down the pressure p. In some embodiments, when y=r (or when y is within the tolerance range r±r), the test sequence controller 148 sends a value of the manipulated variable u, such as u=0, to the pump controller 146, which causes the pneumatic pump 120 to stop drawing down the pressure p. x Once inside, here xindicates the allowable deviation of y from r), the test sequence control 148 sends a command to the pump control 146 to stop the drawdown of negative pressure at the wound 114.

[0069] After the first drawdown period is complete (at t1 as shown in graph 600), according to some embodiments, a leak rate determination period 606 begins. The leak rate determination period 606 is used to determine a slope 612 indicative of the leakage rate of the dressing application (e.g., wound dressing 112, connectors 162-166) on the wound 114. In some embodiments, the slope 612 is calculated based on a leak rate parameter α leak is.

[0070] During the leak rate determination period 606, the test procedure control 148, according to some embodiments, instructs the valve control 150 to wait a predetermined period of time Δt leak The test protocol controller 148 monitors the pressure change over the leak rate determination period 606 to determine the leak rate parameter α for the particular wound application. leak As shown in graph 600, the negative pressure decreases from p1 to p2 from time t=t1 to time t=t2. In some embodiments, the test procedure controller 148 monitors the change (e.g., decrease) in pressure during the leak rate determination period. For example, the test procedure controller 148 may calculate the pressure decrease p1-p2 over the leak rate determination period 606 as a leak rate parameter α leak In some embodiments, the leak rate determination period 606 is a predetermined duration, Δt leak = t2 - t1. In some embodiments, the test sequence controller 148 measures pressure p1 at time t1 and pressure p2 at time t2. In some embodiments, the predetermined time duration Δt leak Over the leak = p1 - p2.

[0071] The leak rate determination period 606, according to some embodiments, is determined by the test procedure control unit 148 for a predetermined period of time Δt leak In some embodiments, the test sequence controller 148 receives and stores values ​​of a performance variable y (e.g., negative pressure) over a period of Δt leak A given period Δt = t2-t1 leak For example, the test procedure control unit 148 receives the value of the performance variable y over a period of Δt leak over a sampling rate of f sample In some embodiments, the sampling rate may be TIFF2025160174000006.tif9128, is the number of samples of the performance variable y received from the pressure sensors 130, 113 per second. For example, if the test procedure control unit 148 receives the value of the performance variable y from the pressure sensors 130, 113 at 10-second intervals (i.e., Δt leak configured to monitor and record for a period of time (t = t - t = 10 seconds), sample = 60Hz (i.e., TIFF2025160174000007.tif8128), the number of samples of the performance variable y over the leak rate determination period 606 is f sample Δt leak = 60Hz·10 seconds = 600 samples. In some embodiments, the samples are measured by the pressure sensors 130 / 113 and the test sequence controller 148 records the samples of the performance variable y in a vector such as: where S1 is the first recorded value of performance variable y during leak rate determination period 606, S2 is the second recorded value of performance variable y during leak rate determination period 606, and so on. w is the wth recorded value of the performance variable y during the leak rate determination period 606, and w is the number of samples of the performance variable y during the leak rate determination period 606 (e.g., w=f sample ·(t2-t1)).

[0072] In some embodiments, the test sequence control unit 148 may TIFF2025160174000009.tif6128. For example, the test procedure control unit 148 stores the time vector TIFF2025160174000010.tif7128 may be stored, where TIFF2025160174000011.tif6128 is the time when S1 is recorded / sampled, TIFF2025160174000012.tif6128 is the time when S2 is recorded / sampled etc. TIFF2025160174000013.tif6128 is the time at which S1 is recorded / sampled. TIFF2025160174000014.tif7128. In some embodiments, TIFF2025160174000015.tif6128. In some embodiments, the time vector Each value in TIFF2025160174000016.tif6128 is TIFF2025160174000017.tif10128. For example, f sample = 60Hz, If TIFF2025160174000018.tif6128 is set to 0, The result is TIFF2025160174000019.tif10128.

[0073] In some embodiments, the test protocol controller 148 may generate a vector of samples of negative pressure at the wound 114. TIFF2025160174000020.tif6128 and Time vector related to TIFF2025160174000021.tif6128 TIFF2025160174000022.tif6128 and based on the slope 612 (i.e., the leak rate parameter α leakIn some embodiments, the test sequence controller 148 determines a slope 612 (i.e., slope m) between successive sampled values ​​(e.g., S2 and S1, S3 and S2, S4 and S3, etc.). For example, the test sequence controller 148 records five sampled values ​​(i.e., w=5) over the leak rate determination period 606, TIFF2025160174000023.tif7128, the test procedure control unit 148 determines the w-1 values ​​of the gradient m. For example, the test procedure control unit 148 TIFF2025160174000024.tif10128. In some embodiments, the test procedure control unit 148 can determine the w-1 value of m and store that value in a slope vector such as: TIFF2025160174000025.tif6128Here, each value of m is judged between the successively occurring value of S and the corresponding / associated value of t when the sample was recorded.

[0074] The test procedure control unit 148 Based on TIFF2025160174000026.tif7128, the leak rate parameter α leak In some embodiments, the test sequence control unit 148 can determine Average the values ​​of TIFF2025160174000027.tif6128 with α leak For example, according to some embodiments, the test procedure control unit 148 may make the following determination: The test procedure control unit 148 also controls the leak rate parameter α according to some embodiments. leak Determine the standard deviation associated with TIFF2025160174000029.tif16128 where, TIFF2025160174000030.tif13128

[0075] In some embodiments, the test sequence control unit 148 Set the maximum or minimum value of TIFF2025160174000031.tif6128 as α leak For example, the test sequence control unit 148 selects α according to some embodiments. leak may be determined as follows: TIFF2025160174000032.tif28128

[0076] In some embodiments, the test sequence control unit 148 Using the initial and final values ​​of TIFF2025160174000033.tif6128, the overall slope m over the entire leak rate determination period 606 is calculated as the leak rate parameter α leak According to some embodiments, the test procedure control unit 148 determines as follows: TIFF2025160174000034.tif12128

[0077] In some embodiments, the leak rate determination period 606 Δt leak (e.g., the time between t2 and t1) is a predetermined period. For example, Δt leak may be 10 seconds, 30 seconds, 5 minutes, etc., according to some embodiments. leak is a predetermined period, the test sequence controller 148 calculates the leak rate parameter α as the change in pressure (e.g., p2 - p1) over the predetermined period. leak For example, Δt leak If is a given value, then α leak = p2 - p1. The leak rate determination period 606 is used to determine the α leak In some embodiments, α leak characterizes the ability of the wound 114 to maintain negative pressure. For example, α leakIf α is very low, this indicates that the wound 114 is well sealed and either the pressure drop over the leak rate determination period is negligible or the slope 612 is near zero, thereby successfully maintaining negative pressure (e.g., no leaks). leak If is very high, this indicates that the wound 114 is not sealed well and may not be able to successfully maintain negative pressure (e.g., identified by a large pressure drop over the leak rate determination period 606 or a large magnitude negative slope 612), according to some embodiments.

[0078] In some embodiments, after the leak rate determination period 606 is completed, the test procedure control unit 148 may TIFF2025160174000035.tif7128 and proceeds to venting period 608. During venting period 608, the test protocol controller 148, according to some embodiments, sends a command to the valve controller 150 to transition the valve 132 to an open configuration, allowing the wound 114 to return to atmospheric pressure. In some embodiments, the test protocol controller 148 causes the valve controller 150 to maintain the valve 132 in the open configuration for a predetermined period of time to allow the pressure p within the wound 114 to return to atmospheric pressure (e.g., 0 mmHg negative pressure). In some embodiments, the test protocol controller 148 monitors the real-time value of the performance variable y received from the pressure sensor 130 / 113 via the pressure monitoring unit 152 and causes the valve controller 150 to maintain the valve 132 in the open configuration until the pressure measurement received from the pressure sensor 130 / 113 is substantially equal to atmospheric pressure, as shown at t3.

[0079] After the wound 114 returns to atmospheric pressure, according to some embodiments, the test sequence controller 148 proceeds to a second drawdown period 610. In some embodiments, the second drawdown period 610 begins with a drawdown time parameter α time This is performed to determine the drawdown time parameter α timeis the time required to achieve a desired negative pressure value (e.g., p1). In some embodiments, the drawdown time parameter α time is the time interval 614. The time interval 614 as shown in FIG. 17 is, according to some embodiments, larger than the time interval 614 as shown in FIG. 16. In some embodiments, the value of the time interval 614 may be adjusted to accommodate a larger volume of the wound 114 and / or a higher leak rate (e.g., α leak 7 may increase due to a higher value of . The slope 612 as shown in FIG. 7 may be substantially equal to the slope 612 as shown in FIG. 6, according to some embodiments. This may indicate that the wound application (e.g., dressing 112) of the test method as shown in FIG. 6 has a substantially equal leak rate compared to the wound application (e.g., dressing 112) of the test method as shown in FIG. 7. Therefore, the increased value of the time interval 614 as shown in FIG. 7 compared to the value of the time interval 614 as shown in FIG. 6 may be due to the test procedure of graph 700 being performed on a wound 114 having a larger volume than the wound 114 of the test procedure of graph 600.

[0080] The test procedure control unit 148 controls the air pressure pump 120 The drawdown time parameter α is set by sending a command (e.g., a value of the manipulated variable u) to the pump control 146 to draw down at a rate of TIFF2025160174000036.tif9128. time The test sequence controller 148 receives pressure measurements from the pressure monitor 152 and / or pressure sensors 130 / 113 and determines the time α that the air pump 120 should operate to achieve the desired pressure (e.g., p1). time In some embodiments, the test sequence control 148 may instruct the pump control 146 to operate the air pressure pump 120 at various drawdown rates. In some embodiments, a fast drawdown rate can cause a command to be sent to draw down according to TIFF2025160174000037.tif9128. timecan be determined more quickly, but time (described in more detail below with reference to model generator 154) is less accurate. In some embodiments, a slower drawdown rate may require adjusting α time can be used, but α time A longer drawdown time (e.g., time interval 614) is required to determine

[0081] In some embodiments, the test procedure controller 148 is configured to send a command to the valve controller 150 to transition the valve 132 to a closed configuration to begin the second drawdown period 610. In some embodiments, after the valve 132 transitions to the closed configuration, the test procedure controller 148 sends a command to the pump controller 146 to begin the second drawdown. In some embodiments, the test procedure controller 148 sends a value of the manipulated variable u to the pump controller 146, causing the air pressure pump 120 to decrease the negative pressure in the wound 114. In some embodiments, the test procedure controller 148 sends a command (e.g., a value of the manipulated variable u) to the pump controller 146 to cause the air pressure pump 120 to draw down according to a predetermined drawdown operation. In some embodiments, the predetermined drawdown operation includes increasing the voltage supplied to the air pressure pump 120 if the air pressure pump 120 cannot achieve the desired negative pressure (e.g., p1) given the current voltage. In some embodiments, the voltage increase of the air pressure pump 120 is performed at predetermined / known time intervals.

[0082] Similar to the first drawdown period 604, the test sequence controller 148 can send values ​​of the manipulated variable u to the pump controller 146 to cause the pneumatic pump 120 to draw down at various drawdown rates over the second drawdown period 610. In some embodiments, a faster drawdown rate can cause the drawdown time parameter α time Although the accuracy of the estimation of the drawdown time parameter α timeSimilarly, a slower drawdown rate can be advantageously used to estimate the drawdown time parameter α time While this allows for a more accurate estimation of the drawdown time parameter α time It takes a long time to estimate.

[0083] During the second drawdown period 610, the test procedure controller 148 monitors the value of the performance variable y received from the pressure sensors 130, 113 via the pressure monitor 152 and compares the value of the performance variable y to a desired / set value r. In some embodiments, the desired / set value r is the negative pressure value (e.g., target pressure value) at the wound 114 that the air pressure pump 120 is attempting to achieve. For example, the set value r can be p1. In some embodiments, the set value r is greater than or less than p1. In this manner, the target pressure value for the second drawdown period 610 can be the same as, greater than, or less than the target pressure value for the first drawdown period 604.

[0084] The test sequence controller 148, according to some embodiments, continues to monitor the value of the performance variable y and monitors the elapsed time since the start (e.g., t3) of the second drawdown period 610. In some embodiments, the test sequence controller 148 includes a timer configured to reset at the start (e.g., t3) of the second drawdown period 610 or to store the time when the second drawdown period 610 begins (e.g., store the value of t3). In some embodiments, the timer resets or records a time value immediately after the valve 132 transitions to the closed configuration and the air pressure pump 120 begins drawing down pressure on the wound 114.

[0085] In some embodiments, when the value of performance variable y becomes substantially equal to (e.g., equal to, within a negligible amount, etc.) a set value r, a timer in the test protocol controller 148 records time t4. In some embodiments, the test protocol controller 148 monitors the time (i.e., t4-t3) required to achieve a desired negative pressure value (e.g., r, p1). In some embodiments, the test protocol controller 148 monitors the time elapsed until drawdown to p1 or r. In some embodiments, the elapsed time Δt drawdown = t4 - t3. In some embodiments, the elapsed time Δt drawdown The amount of time is.

[0086] The test sequence controller 148 executes a test sequence, as described in more detail above, to determine the leak rate parameter α for a known wound 114 volume and / or a known training circuit volume. leak and the drawdown time parameter α time For example, the test procedure controller 148 may execute the test procedure multiple times for a number of different training circuits having known volumes (e.g., 50 cc, 100 cc, 200 cc, 300 cc, etc.). In some embodiments, the test procedure controller 148 is configured to execute the test procedure multiple times for each of the training circuits having known volumes. In some embodiments, the leak rate parameter α leak and the drawdown time parameter α time The resulting values ​​of α are averaged for each of the training circuits to mitigate the amount of random error. For example, the test procedure can be run 10 times on a training circuit with a known volume of 50 cc, and the leak rate parameter α leak and the drawdown time parameter α timemay be averaged to reduce random errors. In some embodiments, the testing procedure is performed for various NPWT systems having different air pressure pumps 120, therapy pressures, training circuit volumes, etc. In some embodiments, the model generator 154 is configured to generate a model for each of a plurality of training circuits using any of the methods and techniques described in more detail below.

[0087] In some embodiments, the training circuit volume includes known volume values ​​of various pipes, canisters, tubing, etc. that the pneumatic pump 120 is configured to draw down. In some embodiments, the training circuit volume includes known wound 114 volume V wound In some embodiments, the training circuit volume is: V training =V system +V wound where V system is a known volume of the various tubes, pipes, canisters, etc. that the pneumatic pump 120 is configured to generate negative pressure within (e.g., the conduit 136, the removal fluid canister 106, the tubing 110, the wound dressing 112, and / or the wound 114), and V wound is the known volume of the wound 114.

[0088] In some embodiments, the testing procedure involves testing various V wound For example, the test procedure can be performed by the controller 118 for multiple values ​​of V wound =50cc, V wound =100cc, V wound In some embodiments, the test procedure may be performed for values ​​such as V = 125 cc. wound is run multiple times for each value of V wound In some embodiments, the mean parameter value associated with a particular value of V system While keeping constant, various values ​​of V wound The test procedure is repeated for the entire training circuit volume Vtraining The change in V wound The test procedure also involves testing multiple leak rates of V wound In some embodiments, the test procedure control unit 148 may run the test procedure multiple times for each value of V. wound For each combination of leak and the drawdown time parameter α time and the model generation unit 154.

[0089] In some embodiments, the controller 118 system In some embodiments, the controller 118 performs a test procedure on various systems having different values ​​of V. wound The test procedure is run multiple times for different values ​​of . In some embodiments, the model generator 154 is configured to generate a model for each of the various systems using any of the methods and techniques described in more detail below. For example, the model generator 154 may generate models of various training circuits that may be used during NPWT.

[0090] In some embodiments, the model generator 154 wound For known values ​​of leak and α time ) to V wound The model generator 154 is configured to determine a model that relates the parameters V to V. The model can be used to determine the volume of the unknown wound 114 during NPWT. wound To create a model relating known values ​​of V to known values ​​of V, the model generator 154 can be configured to perform multivariate regression (e.g., perform a multivariate polynomial curve fit, perform a multivariate linear regression), use a neural network, or create a matrix / table. In some embodiments, the model generator 154 can be configured to generate a model relating known values ​​of V to known values ​​of V. systemFor example, the model generator 154 generates models for V, corresponding to various NPWT circuits that may be used during NPWT. system A table can be constructed for each of the various typical values ​​of .

[0091] Referring again to FIG. 5 , the controller 118 is shown, according to some embodiments, to include a model generator 154. The model generator 154 can be configured to generate a model that defines the relationship between parameters of the dynamic pressure response and the volume of the wound 114. To generate the model, the model generator 154 can cause the test sequence controller 148 to perform the pressure test sequence described above for several different training circuits having several different known volumes (e.g., 50 cc, 100 cc, 200 cc, 300 cc, etc.). When pressure testing is performed on training circuits with known volumes, the pressure test may be referred to as a training sequence. Each performance of a training sequence involves applying a pressure stimulus to a training circuit with a known volume and observing the dynamic pressure response of the training circuit to the pressure stimulus (e.g., α leak and α time and correlating known volumes with the dynamic pressure response of the training circuit.

[0092] In some embodiments, the model generator 154 calculates values ​​of the parameters of the dynamic pressure response for each known volume (i.e., the leak rate parameter α leak and the drawdown time parameter α time ) and associates those values ​​with known volumes. The parameter values ​​and known volumes form a set of training data that can be used to build a model. The parameter values ​​form a set of input training data for the model, and the known volumes form a set of output training data for the model. The model generator 154 can use any of a variety of model generation techniques to build a model (i.e., a mathematical model) that associates the parameter values ​​with corresponding volumes in the set of training data.

[0093] In some embodiments, the model generator 154 system For each typical value of the leak rate parameter α (i.e., a typical negative pressure wound therapy system), an n×m matrix A (i.e., a model) is created. In some embodiments, matrix A is a matrix of leak rate parameter values ​​α leak and the drawdown time parameter value α drawdown , the known wound volume value V associated with the parameter wound In some embodiments, matrix A has the form: TIFF2025160174000038.tif21128 where each column represents the drawdown time parameter α time Each row represents the volume of the wound 114 corresponding to a different value of the leak rate parameter α leak represents different volumes of the wound 114 corresponding to α time and α leak V corresponding to a specific combination of wound In some embodiments, the model generator 154 may generate a dataset representing the volume of V where a particular test was performed. wound The value of α obtained from the test time and α leak In some embodiments, the model generator 154 is configured to receive various data sets including values ​​of α, ... time (e.g., associated with the columns of matrix A) increase from left to right, and α leak are created (e.g., sorted, arranged, generated, constructed, etc.) such that the values ​​of (e.g., associated with the rows of matrix A) increase from top to bottom of matrix A.

[0094] In some embodiments, the model generator 154 also generates a vector corresponding to the rows and columns of the matrix A. In some embodiments, the vector includes a drawdown time parameter α determined through testing of associated volume values.time and the leak rate parameter α leak For example, the drawdown time parameter α time The vector of may be referred to as vector C, according to some embodiments, and may have the form: C=[α time,1 α time,2 ...α time,m ] Similarly, the leak rate parameter α leak The vector of may be referred to as vector B, according to some embodiments, and may have the following form: B=[α leak,1 α leak,2 ...α leak,n ]

[0095] 9 based on the data set received from the test sequence control unit 148. Table 900 includes a horizontal / top header 902 and a vertical / side header 904, according to some embodiments. In some embodiments, the top header 902 includes a time represents various values ​​of V wound The side header 904 represents the columns corresponding to various values ​​of α leak The rows represent various values ​​of V wound In some embodiments, the top header 902 and V wound The corresponding column of values ​​is α time are sorted in ascending order of α time The lower value of is far to the left, time Similarly, the side header 904, according to some embodiments, leak are sorted in ascending order of α leak The lower value of α is at the top of the side header 904, leak The higher value of is at the bottom of the side header 904.

[0096] In some embodiments, the model generator 154 wound and the corresponding value of α time and αleak Perform a multivariate regression based on the parameters. In some embodiments, the model generator 154 performs a multivariate linear regression to determine the following equation: V wound =C1α time +C2α leak +C3 where C1, C2, and C3 are constants determined by the model generator 154 by performing a multivariate linear regression.

[0097] In some embodiments, the model generator 154 performs a multivariate nonlinear regression to determine: V wound =f1(α time )+f2(α leak ) where f1 is the α time is a nonlinear function of α, determined by performing a nonlinear multivariate regression. leak In some embodiments, any of the above equations has the general form: V wound =f wound (α time ,α leak ) where f wound is α leak and α time and V wound In some embodiments, f wound is V wound Various values ​​of and V wound α corresponding to each value of time and α leak It is determined by performing a multivariate regression on the associated values ​​of

[0098] In some embodiments, the model generator 154 uses a polynomial approximation model to associate values ​​of the parameters with corresponding volumes, f woundTo generate the polynomial approximation model, the model generator 154 can perform a curve fitting process, such as polynomial regression, using any of a variety of regression techniques. Examples of regression techniques that the model generator 154 can use include least squares, ordinary least squares, linear least squares, partial least squares, total least squares, generalized least squares, weighted least squares, nonlinear least squares, nonnegative least squares, iteratively reweighted least squares, ridge regression, least absolute deviation, Bayesian linear regression, and Bayesian multivariate linear regression.

[0099] In some embodiments, f wound is generated by the model generation unit 154 using a neural network. To generate the neural network model, the model generation unit 154 may perform a machine learning process. Examples of machine learning techniques that the model generation unit 154 may use include decision tree learning, association rule learning, artificial neural networks, deep learning, inductive logic programming, support vector machines, clustering, Bayesian networks, reinforcement learning, representation learning, similarity metric learning, sparse dictionary learning, genetic algorithms, and rule-based machine learning.

[0100] 5, the controller 118 is shown to include a wound volume estimator 156 according to some embodiments. In some embodiments, the wound volume estimator 156 uses matrix A and associated vectors B and C, table 900, and / or a mathematical model (e.g., f) determined by the model generator 154. wound) for the unknown wound volume. In some embodiments, the wound volume estimator 156 is configured to cause the test procedure controller 148 to perform a test procedure, such as that described in more detail above with reference to FIG. 6, for the unknown wound volume. In some embodiments, the wound volume estimator 156 is configured to perform the test procedure. For example, the wound volume estimator 156 may be configured to perform any of the functions of the test procedure controller 148 (e.g., performing the first drawdown period 604, operating the valve 132, controlling the air pressure pump 120, etc.). In some embodiments, the wound volume estimator 156 is configured to perform a test procedure, such as that described in more detail above with reference to FIG. 6 for the unknown wound volume. time and α leak Determine the value of α time and α leak from the test protocol controller 148. In some embodiments, the wound volume estimator 156 uses the mathematical model (e.g., f) generated and received from the model generator 154 to estimate the wound volume. wound ), matrix A, table 900, etc. to determine an estimate of the unknown value of α. In some embodiments, the wound volume estimator 156 uses table 900 and / or matrix A to determine an estimate of the unknown value of α time and α leak One or both of the values ​​of α are stored in vectors B and C or in table 900. time and α leak If the value does not correspond to V, the wound volume estimator 156 wound The method is configured to perform interpolation to determine

[0101] In some embodiments, the wound volume estimator 156 uses the table 900 to calculate the parameter α determined as a result of performing a test procedure on a wound 114 having an unknown volume. time and α leak Based on the unknown value V wound In some embodiments, the wound volume estimator 156 first determines the α leak If any of the values ​​of V wound α, determined by performing the test procedure on a wound 114 having leakFor example, the wound volume estimator 156 may check the value of α leak The α of side header 904 leak,2 If it is determined that the wound volume is substantially equal to V wound The value of α leak,2 Next, the wound volume estimator 156 determines that the value of V in the row corresponding to α time Various values ​​of α are determined by performing a test procedure on the wound 114. time For example, the wound volume estimator 156 may compare the value of α time is α time,5 is substantially equal to α leak is α leak,2 If it is determined that the volume of the wound 114 is substantially equal to V, the wound volume estimator 156 determines that the volume of the wound 114 is V 2,5 It can be determined that the value is substantially equal to

[0102] In some embodiments, the wound volume estimator 156 calculates α leak and / or α time do not correspond to the values ​​in the side header 904 and top header 902, respectively, the wound volume estimator 156 may perform interpolation or extrapolation to determine the volume of the wound 114. In some embodiments, the wound volume estimator 156 uses any of the values ​​in table 900 in a multivariate linear interpolation (or extrapolation) to determine the volume of the wound 114. In some embodiments, the wound volume estimator 156 performs a non-linear interpolation to determine the volume of the wound 114.

[0103] The wound volume estimator 156 may similarly be configured to use matrix A and vectors B and C to determine the volume of the wound 114. For example, the wound volume estimator 156 may calculate α time The value of is compared with the element value of vector C to determine the column value of matrix A, and α leak The value of can be compared with the value of the elements of vector B to determine the row value of matrix A. For example, α time is equal to the fifth element of vector C, and αleak is equal to the tenth element of the vector C, the wound volume estimator 156 calculates V of the wound 114 as wound as A(10,5) or V 10,5 Similarly, the wound volume estimator 156 can select α time and / or α leak V related to the value of wound The wound volume estimator 156 may be configured to interpolate or extrapolate values ​​of matrix A to determine the value of . In some embodiments, the wound volume estimator 156 is configured to use a linear multivariate interpolation technique or a non-linear interpolation technique.

[0104] In some embodiments, the wound volume estimator 156 uses a linear regression equation (e.g., V wound =C1α time +C2α leak +C3), nonlinear regression equations (e.g., V wound =f1(α time )+f2(α leak )), or using data received from the test sequence controller 148 for known volumes, determined using any of the methods described in more detail above (e.g., a mathematical model generated using a machine learning algorithm, generated using a polynomial curve fit, generated using linear regression (e.g., generally, V wound =f wound (α time ,α leak For example, the wound volume estimator 156 may be configured to estimate the volume V of the wound 114 using either wound To determine leak and α time The determined value of f (e.g., a parameter resulting from performing a test procedure on a wound 114 having an unknown volume) is wound In some embodiments, the wound volume estimator 156 may calculate the volume of the circuit that the air pressure pump 120 is configured to draw down (e.g., V system ), a suitable model (e.g., a suitable table 900, a suitable matrix A, a suitable f woundFor example, the wound volume estimator 156 may be configured to select an appropriate f generated from a test procedure for a system with a similar volume. wound The model can be wound You can choose from a database of models.

[0105] Advantageously, V wound To determine α time and α leak By using both α and α , according to some embodiments, air leaks into the inner volume 160 of the wound 114. time For example, the inaccuracy or deviation of the volume V wound High leak rates in wounds with leak (high value) wound application example, the same volume V wound but with a low leak rate (e.g., α leak compared with wounds with low α time The value of α may be high. time and α leak By considering both, the model generator 154 and wound volume estimator 156 can take into account the degree of leakage for a particular wound and determine whether the leakage rate is high or low (e.g., α leak Regardless of whether the value of V is high or low wound can be accurately determined.

[0106] Flow diagram 10-11 , a graph 1000 and process 1100 illustrating application of a wound volume estimate are shown, according to an exemplary embodiment. The controller 118 can calculate a volume of infusion fluid 105 to deliver to the wound 114 using the estimated wound volume (step 1102). In some embodiments, the controller 118 calculates the volume of infusion fluid 105 to deliver to the wound 114 by multiplying the estimated wound volume by a fluid drip factor. The fluid drip factor can be less than one (i.e., between zero and one) so that the calculated volume of infusion fluid 105 is less than the volume of the wound 114. In some embodiments, the fluid drip factor is between about 0.2 and about 0.8. However, it is contemplated that the fluid drip factor can have any value in various alternative embodiments.

[0107] In graph 1000, line 1002 represents the estimated volume of the wound 114 as a function of time, while line 1004 represents the calculated volume of infusion fluid 105 delivered to the wound 114 over time. At time t1, the estimated volume of the wound 114 is V4. The estimated wound volume V4 at time t1 can be multiplied by a fluid infusion factor F (e.g., F=0.8) to calculate a volume V3 of infusion fluid 105 delivered to the wound 114 at time t1 (i.e., V4*F=V3). As the wound 114 heals, the estimated volume of the wound 114 decreases, reaching a value of V2 at time t2. The estimated wound volume V2 at time t2 can be multiplied by the fluid infusion factor F to calculate a volume V1 of infusion fluid 105 delivered to the wound 114 at time t2 (i.e., V2*F=V1).

[0108] The controller 118 can then operate the pump to deliver the calculated volume of infusion fluid 105 to the wound 114 (step 1104). Step 1104 can include operating the infusion pump 122 to draw infusion fluid 105 from the infusion fluid canister 104 and deliver the infusion fluid 105 to the wound 114 via tubing 109 and 108. In some embodiments, the calculated volume of infusion fluid 105 is also used to control the operation of the pneumatic pump 120. For example, the controller 118 can operate the pneumatic pump 120 to remove a volume of infusion fluid 105 from the wound 114 via tubing 110. The amount of time the pneumatic pump 120 operates can be a function of the volume of infusion fluid 105 delivered to the wound 114.

[0109] 12A-12B, according to some embodiments, one or more parameters (e.g., α leak and α time ) into the wound volume (e.g., V wound ) to the model (e.g., f wound ) is shown. In some embodiments, the controller 118 is configured to perform the process 1200. In some embodiments, the process 1200 is performed by the controller 118 and / or various components of the NPWT system 100. In some embodiments, the process 1200 is performed by the controller 118 when the controller 118 generates f wound 12 illustrates various steps that can be performed to determine the presence or absence of a signal. In some embodiments, process 1200 is the testing procedure described in more detail above with reference to FIGS. 5-7. Process 1200, according to some embodiments, includes steps 1202-1226.

[0110] The process 1200, according to some embodiments, wound for a known volume V systemIn some embodiments, providing the NPC circuit to the known wound includes establishing the NPC circuit by providing a wound dressing 112 to the patient's skin 116 over the wound 114 (step 1202). wound is the known volume of the wound 114. For example, step 1202 may involve measuring the volume of a test wound (e.g., a known volume V wound NPWT system 100 (e.g., a wound 114 having a known V system In some embodiments, step 1202 includes configuring the NPWT system 100 and starting the therapy device 102.

[0111] The process 1200, according to some embodiments, woundIn some embodiments, step 1204 includes operating the pump to draw down negative pressure at the wound 114 to achieve p1 at 100 mmHg. In some embodiments, step 1204 is the first drawdown period 604. In some embodiments, the pump is the pneumatic pump 120. In some embodiments, step 1204 includes any of the functions, techniques, steps, etc. of the first drawdown period 604. In some embodiments, step 1204 is performed by the test protocol controller 148. In some embodiments, p1 is 200 mmHg. In some embodiments, step 1204 is performed by the test protocol controller 148 and the pump controller 146. The pneumatic pump 120, according to some embodiments, is configured to generate negative pressure at the wound 114. In some embodiments, step 1204 includes the test sequence controller 148 monitoring the pressure measurement at the wound 114 via the pressure sensors 130, 113 and continuing to cause the air pressure pump 120 to draw down negative pressure until the measured / monitored pressure is substantially equal to p1. In some embodiments, step 1204 is also performed by the valve controller. In some embodiments, step 1204 includes the valve controller 150 sending a control signal to the valve 132 to transition the valve 132 to a closed configuration to allow the air pressure pump 120 to draw down negative pressure at the wound 114.

[0112] Process 1200, according to some embodiments, leak over a known volume V wound (step 1206). In some embodiments, step 1206 is the leak rate determination period 606. In some embodiments, the controller 118 is configured to perform step 1206. In some embodiments, step 1206 is performed by the test procedure control unit 148. For example, the test procedure control unit 148 may perform step 1206 by recording the pressure value for the period Δt leakThe pressure sensor 130 / 113 may be configured to receive pressure measurements from the pressure sensor 130 / 113 over a period of time (e.g., t2-t1 as shown in FIG. 6). In some embodiments, step 1206 includes recording multiple pressure values ​​of negative pressure (e.g., vacuum pressure) at the wound 114. In some embodiments, step 1206 includes recording multiple pressure values ​​of negative pressure (e.g., vacuum pressure) at the wound 114 over a period of time Δt leak recording an initial pressure value (e.g., p1) of the wound 114 at the beginning of a period Δt leak and recording a final pressure value (e.g., p2) at the end of step 1206. In some embodiments, step 1206 is performed by the test sequence controller 148 and the pressure monitor 152.

[0113] Process 1200, according to some embodiments, includes venting wound 114 to atmospheric pressure (step 1208). In some embodiments, step 1208 is performed after step 1210. In some embodiments, steps 1208 and 1210 are performed simultaneously. In some embodiments, step 1208 is performed by test protocol controller 148 and valve controller 150. For example, step 1208 may include test protocol controller 148 sending a command to valve controller 150 to transition valve 132 to an open configuration to allow wound 114 to return to atmospheric pressure. In some embodiments, step 1208 is performed by test protocol controller, valve controller 150, and valve 132. In some embodiments, step 1208 is a vent period 608.

[0114] Process 1200, according to some embodiments, determines V based on the pressure value of the wound 114 recorded during step 1206. wound The leak rate parameter α leak In some embodiments, step 1210 is performed by test sequence control unit 148. In some embodiments, α leak is the time interval Δt leak is the difference between the initial and final pressure values. leakis the slope 612. In some embodiments, TIFF2025160174000039.tif10128.

[0115] Process 1200, according to some embodiments, includes repeating steps 1202-1210 (step 1212). In some embodiments, controller 118 and / or NPWT system 100 may adjust α leak Steps 1202-1210 are repeated X times to determine the average value of , and minimize random error. In some embodiments, step 1212 is optional.

[0116] Process 1200, according to some embodiments, includes operating a pump (e.g., air pressure pump 120) to draw down negative pressure in wound 114 to achieve p1 (step 1214). In some embodiments, step 1214 is the second drawdown period 610. In some embodiments, step 1214 is performed by test sequence controller 148, pump controller 146, and air pressure pump 120. In some embodiments, the pressure is drawn down to pressure p1. In some embodiments, the pressure is drawn down to a pressure greater than or less than pressure p1.

[0117] The process 1200, according to some embodiments, determines the duration Δt drawdown α time In some embodiments, the duration Δt drawdown is the time interval 614. In some embodiments, α time is the time that the air pressure pump 120 must operate to achieve pressure p1. In some embodiments, step 1216 is performed by the test sequence controller 148.

[0118] The process 1200, according to some embodiments, timeIn some embodiments, steps 1214-1216 are repeated Y times to determine the average value of α (step 1218). time Steps 1214-1216 are repeated to reduce the amount of random error in the quantization. In some embodiments, step 1218 is optional.

[0119] Process 1200, according to some embodiments, wound The leak rate parameter α related to the value of leak and the drawdown time parameter V wound In some embodiments, step 1220 includes recording the matrix N=[α time α leak V wound ] and providing matrix N to model generator 154. In some embodiments, matrix N is stored and additional rows of matrix N are defined by performing additional steps 1202-1220.

[0120] Process 1200, according to some embodiments, wound , α leak , and α time This involves repeating steps 1202-1220 for different values ​​of V (step 1222). In some embodiments, each additional iteration of steps 1202-1220 results in an additional row of matrix N. In some embodiments, steps 1202-1220 are performed until a sufficient amount of test data has been recorded in matrix N. In some embodiments, steps 1202-1220 are performed for various values ​​of V, which are typical. wound values, and various leakage α values ​​that may be encountered during NPWT leak is executed against.

[0121] Process 1200, according to some embodiments, calculates V based on a recorded data set (e.g., matrix N). system For the current value of Vwound α leak and α time A model that associates wound ) (step 1224). In some embodiments, step 1224 is performed by the model generator 154. In some embodiments, step 1224 includes providing the recorded data set (e.g., matrix N) to the model generator 154. In some embodiments, the generated model includes matrix A, table 900, f wound In some embodiments, step 1224 includes wound In some embodiments, step 1224 includes ordering, sorting, etc., matrix N to generate matrix A or table 900. In some embodiments, V system A model is generated for each of a plurality of values ​​of . In some embodiments, step 1224 includes providing the generated model to the wound volume estimator 156.

[0122] Process 1200, according to some embodiments, system For each of the various values ​​of α leak and α time V wound To determine the model associated with V system In some embodiments, step 1226 includes performing steps 1204-1224 for different values ​​of V. In some embodiments, step 1226 includes performing steps 1204-1224 for different NPWT systems. In some embodiments, step 1226 is performed by the controller 118 and a test technician (e.g., step 1202 is performed by testing the current NPWT system with different V system (This may include replacing the system with a different system having

[0123] Referring now to FIG. 13, according to some embodiments, the volume V of the wound 114 is wound13 illustrates a process 1300 for determining the volume of the wound 114 (i.e., when the volume of the wound 114 is unknown). Process 1300 may rely on the model(s) generated in process 1200 by model generator 154. In some embodiments, process 1300 may be performed intermittently during NPWT to determine the volume of the wound 114. Process 1300 may be performed by controller 118. Process 1300, according to some embodiments, includes steps 1302-1308.

[0124] Process 1300, according to some embodiments, wound The leak rate parameter α for unknown values ​​of leak In some embodiments, step 1302 is performed by controller 118.

[0125] Process 1300, according to some embodiments, wound (Step 1304) Drawdown time parameter α for unknown values time (Step 1304) includes performing steps 1214-1216. In some embodiments, step 1304 is performed by controller 118.

[0126] Process 1300, according to some embodiments, applies α to the model generated by model generator 154 in process 1200. leak and α time In some embodiments, step 1306 includes inputting V wound To determine V system For the current NPWT system with α leak and α time f woundに In some embodiments, step 1306 is performed by the wound volume estimator 156. In some embodiments, step 1306 includes inputting αleak and α time Based on the V in table 900 and / or matrix A wound In some embodiments, step 1306 includes looking up a value of α leak does not match any of the values ​​in the side header 904 and / or vector B, or α time does not match any of the values ​​in the top header 902 and / or vector C, then V wound This includes interpolating or extrapolating to determine the value of

[0127] Process 1300 may be implemented by determining V in step 1306, according to some embodiments. wound determining the infusion fluid volume based on the calculated infusion volume (step 1308). In some embodiments, step 1308 is performed by controller 118. In some embodiments, step 1308 is step 1101 of process 1100.

[0128] 14, a process 1400 for operating the therapy device 102 is shown, according to some embodiments. The process 1400 may be performed by the controller 118, the communication interface 124, and the user interface 126. In some embodiments, the process 1400 is a process for determining the volume of a wound (e.g., the wound 114).

[0129] Process 1400, according to some embodiments, begins with the power-up of therapy device 102 (step 1402). In some embodiments, after therapy device 102 powers up, process 1200 proceeds to step 1404. In step 1404, controller 118 can receive a command from a user to transition therapy device 102 to a fill assist mode, a manual volume transfer mode, or an automatic volume determination mode. In some embodiments, the command is received via user interface 126. If the user sends a command to transition therapy device 102 to fill assist mode, therapy device 102 transitions to fill assist mode, and process 1400, according to some embodiments, proceeds to step 1420. If the user sends a command to transition therapy device 102 to a manual volume entry mode, according to some embodiments, process 1400 proceeds to step 1426. If the user sends a command to transition therapy device 102 to an automatic volume detection mode, according to some embodiments, process 1400 proceeds to step 1406.

[0130] The process 1400, according to some embodiments, calculates a leak rate parameter α leak and the drawdown time parameter α time 14. In some embodiments, the test procedure is the test procedure described in more detail above with reference to FIG. 6. In some embodiments, the test procedure is process 1300. In some embodiments, step 1406 is performed by controller 118 and / or test procedure control 148.

[0131] The process 1400, according to some embodiments, calculates a leak rate parameter α leak and the drawdown time parameter α time Based on V wound In some embodiments, step 1408 is performed by the wound volume estimator 156 using the model generated by the model generator 154. In some embodiments, the model fwound , or table 900, or matrix A (and vectors B and C) are system In some embodiments, step 1408 is step 1306 of process 1300. ... wound To determine the leak rate parameter α leak and the drawdown time parameter α time into a model (as generated by model generator 154 described in more detail above).

[0132] Process 1400 may, according to some embodiments, include a step 1408 via user interface 126 to determine V wound In some embodiments, in response to completing step 1408, displaying the value of V wound The value of V is displayed via the user interface 126. In some embodiments, wound The value of V wound along with confirmation from the user to accept or reject the value of .times. ...

[0133] Process 1400, according to some embodiments, begins when a user selects the V determined in step 1408. wound In some embodiments, the process includes determining (e.g., receiving input from) whether the value of V is acceptable (step 1412). wound In some embodiments, the controller 118 may prompt the user to confirm the value of V wound The controller 118 receives a command from the user indicating whether the user has accepted the value of V (e.g., a YES or NO command). wound If a command is received from the user indicating that the value of V is accepted (YES), then according to some embodiments, process 1400 proceeds to step 1414.wound If a command is received from the user indicating that the value of is rejected (NO), the process 1400 proceeds to step 1416 .

[0134] Process 1400, according to some embodiments, includes a V wound (step 1414). In some embodiments, step 1414 is performed by controller 118. In some embodiments, step 1414 includes setting a value of V wound determining an infusion volume (e.g., a volume of infusion fluid 105 provided to the wound 114) based on the value of . In some embodiments, step 1414 includes performing process 1100. In some embodiments, process 1400 terminates in response to completing step 1414 (step 1428).

[0135] The controller 118 allows the user to wound If the controller 118 receives a command via the user interface 126 rejecting the value of , according to some embodiments, process 1400 proceeds to step 1416. In some embodiments, step 1416 includes requesting input from the user via the user interface 126 as to whether the automatic volume estimation (i.e., steps 1406-1410) should be performed again. In some embodiments, if the controller 118 receives a command from the user via the user interface 126 to re-run the automatic volume estimation, process 1400 returns to step 1406. If the controller 118 receives a command from the user via the user interface 126 indicating that the automatic volume estimation should not be performed again, according to some embodiments, process 1400 proceeds to step 1418.

[0136] Process 1400, according to some embodiments, includes prompting the user whether to enter a fill assist mode (step 1418). In some embodiments, step 1418 includes providing the request to the user via user interface 126. In some embodiments, if controller 118 receives a command from the user via user interface 126 to perform a fill assist (YES, step 1418), process 1400 proceeds to step 1420. In some embodiments, if controller 118 receives a command from the user via user interface 126 that a fill assist operation should not be performed (NO, step 1418), process 1400 proceeds to step 1424.

[0137] Process 1400, according to some embodiments, includes performing a fill assist operation (step 1420). In some embodiments, the fill assist operation is performed by controller 118 and infusion pump 122. In some embodiments, the fill assist operation includes a user manually indicating an amount of infusion fluid 105 to be provided to wound 114 by manually operating infusion pump 122. Controller 118 is configured to measure the amount of infusion fluid 105 applied to wound 114 by infusion pump 122 during the fill assist operation (controlled by the user), and calculates V based on the amount of infusion fluid applied to wound 114 during the fill assist operation. wound may be determined (step 1422). In some embodiments, in response to completing the fill assist operation, process 1400 proceeds to step 1428.

[0138] If the controller 118 receives a command via the user interface 126 that a fill assist operation should not be performed (step 1418, NO), then, according to some embodiments, the process 1400 proceeds to step 1424. In step 1424, the controller 118 receives a manual volume input via the user interface 126, according to some embodiments. In some embodiments, in response to receiving a manual volume input via the user interface 126, the process 1400 proceeds to step 1426. In step 1426, the controller 118 determines whether the manually entered volume (e.g., manually entered V wound ) is set as the infusion fluid volume. In some embodiments, after the manually entered volume is set as the infusion fluid volume, process 1400 proceeds to step 1428.

[0139] Configuration of an exemplary embodiment The structure and configuration of the systems and methods shown in the various exemplary embodiments are merely exemplary. While only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in the size, dimensions, structure, shape, and proportions of various elements, parameter values, mounting configurations, use of materials, color, orientation, etc.). For example, the positions of elements can be reversed or otherwise varied, and the nature or number or location of distinct elements can be changed or varied. Accordingly, all such modifications are intended to be included within the scope of this disclosure. The order or sequence of any process or method steps can be varied or re-ordered according to alternative embodiments. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions, and configuration of the exemplary embodiments without departing from the scope of this disclosure.

[0140] The present disclosure contemplates methods, systems, and program products on any machine-readable medium for accomplishing various operations. Embodiments of the present disclosure can be implemented using an existing computer processor, by a dedicated computer processor for a suitable system incorporated for this or another purpose, or by a hardwired system. Embodiments within the scope of the present disclosure include program products including machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media may be any available medium 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 can comprise RAM, ROM, EPROM, EEPROM, CD-ROM, or other optical disk storage, magnetic disk storage, or other magnetic storage, 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 that can be accessed by a general-purpose or special-purpose computer or other machine with a processor. Combinations of the above 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, special-purpose computer, or special-purpose processing machine to perform a certain function or group of functions.

[0141] While the figures show method steps in a particular order, the order of the steps may differ from that depicted. Also, two or more steps may be performed concurrently or with partial concurrence. Such variations depend on the software and hardware systems selected and on the designer's choice. All such variations are within the scope of this disclosure. Similarly, software implementations may be accomplished with standard programming techniques using rule-based logic and other logic to accomplish the various connection, processing, comparison, and decision steps.

Claims

1. a negative pressure circuit configured to apply negative pressure to the wound; a pump fluidly connected to the negative pressure circuit and configured to generate negative pressure at the wound or within the negative pressure circuit; a pressure sensor configured to measure the negative pressure in the negative pressure circuit or at the wound; a controller, executing a test procedure including a first drawdown period, a leak rate determination period, a vent period, and a second drawdown period; receiving one or more pressure measurements of the pressure sensor over the leak rate determination period to determine a leak rate parameter; monitoring elapsed time over the second drawdown period to determine drawdown parameters; a controller configured to estimate a volume of the wound based on the leak rate parameter and the drawdown parameter; A wound therapy system comprising:

2. 2. The system of claim 1, wherein the first drawdown period comprises operating the pump to achieve a predetermined negative pressure in the negative pressure circuit.

3. The system of claim 2 , wherein the leak rate determination period includes maintaining the predetermined negative pressure for a predetermined duration and receiving a pressure measurement from the pressure sensor during the predetermined duration.

4. The system of claim 1 , wherein the leak rate parameter is a change in pressure in the negative pressure circuit over the leak rate determination period.

5. The system of claim 1 , wherein the leak rate parameter is a change in pressure with respect to time over at least a portion of the leak rate determination period.

6. The system of claim 1 , wherein the venting period includes opening a valve in the negative pressure circuit to return the negative pressure circuit to atmospheric pressure.

7. 10. The system of claim 1, wherein the second drawdown period comprises operating the pump to generate negative pressure in the negative pressure circuit at a predetermined rate.

8. 8. The system of claim 7, wherein the drawdown parameter is the time the pump operates at the predetermined speed to achieve a predetermined pressure value in the negative pressure circuit.

9. 2. The system of claim 1, wherein the controller is further configured to estimate the volume of the wound by inputting the drawdown parameter and the leak rate parameter into a model relating the volume of the wound to the drawdown parameter and the leak rate parameter.

10. The model is performing the test procedure for a plurality of known values ​​of the volume of the wound; determining the model based on the plurality of known values ​​of the volume of the wound and a leak rate parameter and a drawdown parameter associated with each of the plurality of known values ​​of the volume of the wound; The system of claim 9 , wherein the determination is made by:

11. providing a negative pressure circuit configured to apply negative pressure to the wound; providing a pump fluidly connected to the negative pressure circuit and configured to generate negative pressure at the wound or within the negative pressure circuit; providing a pressure sensor configured to measure the negative pressure in the negative pressure circuit or at the wound; performing a test procedure for the known value of wound volume, the test procedure including performing a first drawdown for a first drawdown period, performing a leak rate for a leak rate determination period, evacuating the negative pressure circuit, and performing a second drawdown for a second drawdown period; receiving one or more pressure measurements of the pressure sensor over the leak rate determination period to determine a leak rate parameter; monitoring elapsed time over the second drawdown period to determine drawdown parameters; generating a model based on the known value of the volume of the wound, the leak rate parameter, and the drawdown parameter, the model relating the volume of the wound to the leak rate parameter and the drawdown parameter; re-performing the steps of performing the test procedure, receiving the one or more pressure measurements, and monitoring the elapsed time to determine leak rate and drawdown parameters for the unknown value of the volume of the wound; and determining estimating the unknown value of the volume of the wound by inputting the leak rate parameter and the drawdown parameter associated with the unknown value of the volume of the wound into the model; 1. A method for determining wound volume, comprising:

12. 12. The method of claim 11, wherein the first drawdown comprises operating the pump to achieve a predetermined negative pressure in the negative pressure circuit, and wherein the leak rate determination comprises maintaining the predetermined negative pressure for a predetermined duration and receiving a pressure measurement from the pressure sensor during the predetermined duration.

13. The method of claim 11 , wherein the leak rate parameter is a change in pressure in the negative pressure circuit over the leak rate determination period.

14. The method of claim 11 , wherein the leak rate parameter is a rate of change of pressure in the negative pressure circuit with respect to time over at least a portion of the leak rate determination period.

15. 12. The system of claim 11, wherein venting the negative pressure circuit comprises opening a valve in the negative pressure circuit to return the negative pressure circuit to atmospheric pressure.

16. 12. The method of claim 11, wherein the second drawdown comprises operating the pump to generate negative pressure in the negative pressure circuit at a predetermined drawdown rate.

17. 17. The method of claim 16, wherein the drawdown parameter is the time the pump operates at the predetermined drawdown rate to achieve a predetermined pressure value in the negative pressure circuit.

18. The model is performing the test procedure for a plurality of known values ​​of the volume of the wound to determine a plurality of values ​​of the leak rate parameter and the drawdown parameter; performing a regression on the plurality of values ​​of the volume of the wound and the plurality of values ​​of the leak rate parameter and the drawdown parameter; The system of claim 11 , wherein the determination is made by:

19. The method of claim 11 , wherein the model includes a look-up table relating the leak rate parameter and the drawdown parameter to the volume of the wound.

20. a pump fluidly connected to a negative pressure circuit and configured to generate negative pressure at or within the negative pressure circuit, the negative pressure circuit configured to apply negative pressure to the wound; a pressure sensor configured to measure the negative pressure in the negative pressure circuit or at the wound; a controller, Operate the pump to generate negative pressure in the negative pressure circuit; receiving one or more pressure measurements of the pressure sensor over a predetermined period of time; determining a leak rate based on the received one or more pressure measurements of the pressure sensor over the predetermined period of time; venting the negative pressure circuit to atmospheric pressure; activating the pump to reduce the pressure in the negative pressure circuit at a predetermined rate; monitoring the elapsed time that the pump operates at the predetermined speed until a predetermined pressure is reached in the negative pressure circuit; a controller configured to estimate a volume of the wound based on the leakage rate and the elapsed time; A wound therapy device comprising:

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