Detecting leaks in negative pressure wound therapy systems

Abstract

Techniques for detecting leaks in negative pressure wound therapy (NPWT) systems are described. According to an example of the present subject matter, a frequency spectrum of sound emanating from a NPWT system is analysed to determine whether the frequency spectrum comprises frequencies in a predetermined range of frequencies corresponding to leakage of fluid from the NPWT system. Based on presence of frequencies corresponding to the predetermined range of frequencies a leak in the NPWT system may be identified.

Description

DETECTING LEAKS IN NEGATIVE PRESSURE WOUND THERAPY SYSTEMSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 530,261, filed on August 2, 2023, which is incorporated herein by reference in its entirety.BACKGROUND

[0002] Application of localized negative pressure over wounds has been found to aid healing of the wounds. The reduced pressure enhances blood flow to the site of a wound and is effective in promoting growth of new tissues to repair wounded tissues. The reduced pressure also helps in draining away of blood or other fluids that may exudate of the wound to avoid any potential infection that such fluids may cause and to inhibit growth of pathogens around the site of the wound.

[0003] Negative pressure wound therapy (NPWT) systems work to create and maintain localized negative pressure at the site of the wound. A NPWT system comprises a NPWT dressing that serves to create a sealed space over the wound for application of the negative pressure. The NPWT dressing generally includes an adhesive layer that secures the dressing to areas around the wound to form the air-tight sealing. The NPWT dressing may also include other components that may serve to absorb fluids and distribute the negative pressure evenly across the wound.

[0004] An air-tight manifold is provided on the NPWT dressing to introduce a conduit. The conduit enables a fluid communication of the NPWT dressing to an external pump which can suction air from within the air-tight sealing over the wound to create the negative pressure and / or to pump fluid out of the NPWT dressing. Leakages, if any, in the NPWT dressing that occur during the course of the negative pressure therapy are sealed so that a desired negative pressure is consistently maintained at the site of the wound.SUMMARY

[0005] A negative pressure wound therapy (NPWT) system operates to establish negative pressure within a sealed space formed by a NPWT dressing over a site of a wound on a patient. The NPWT dressing is provided with a conduit that connects to a pump that establishes the negative pressure. A predetermined negative pressure is maintained within the sealed space throughout the duration of the treatment of the patient.

[0006] Failure to maintain the predetermined negative pressure, for instance, due to leakages in the NPWT system may impact the effectiveness of the treatment. A leak in the NPWT system may lead to less than desired predetermined negative pressure being applied to the site of the wound and may, for instance, result in the treatment being ineffective or taking longer than it otherwise would. Thus, leaks in NPWT systems are promptly identified and sealed.

[0007] Given the bearing that the leakages have on the effectiveness of the treatment, the NPWT systems generally incorporate techniques to allow detection of leaks. For example, a NPWT system may detect a leak if the predetermined negative pressure is not achieved after lapse of a threshold time duration of operation of the pump.

[0008] While a NPWT system may indicate that a leak may be present, often, confirmation and identification of the leak in order to seal the same is difficult. The leak may be present in any of the components of the NPWT system, such as a tubing, connection, trackpad and / or NPWT dressing. Identification of the leak may require inspection of these components so as to pinpoint a location of the leak in the NPWT system. For instance, for a NPWT dressing applied to create a seal around the periphery of a substantially large-sized wound, each portion of the periphery of the NPWT dressing may have to inspected for detection of the leak. Manual inspection to detect the leak may not only be cumbersome but also inaccurate. This is specifically true for an NPWT system being used in a home environment, where it is generally not operated and monitored by medical professionals.

[0009] In some cases, specialized leak detection devices may be used to identify the location of the leak in the NPWT system. However, such devices generally being costly may not be readily available. Consequently, attempts to detect leaks by patients as well as by medical professional often fail or yield incorrect results. Incorrect identification of the location of the leak may result in further alarms due to the inability to seal the leak and failure to maintain the desired negative pressure at the wound site in the presence of a leak. In some cases, owing to the frustration caused due to failed attempts to identify the leaks and the frequent alarms, patients may discontinue the treatment.

[0010] In some other cases, the patients or the medical professionals may seek technical assistance from the manufacturer of the NPWT system. For example, the patients or the medical professionals may reach out to a call centre associated with the manufacturer of the NPWT system. Nevertheless, the additional time and effort involved in seeking such technical assistance often results in customer dissatisfaction. Also, the manufacturer of the NPWT system may incur cost to allocate resources to respond to numerous calls that may result from the inability of the patients and medical professionals to detect leaks at their end.

[0011] Example techniques to detect leaks in NPWT systems are described herein.

[0012] In accordance with example implementations of the present subject matter, a method for detecting leaks in a NPWT system, comprises obtaining audio signals emanating from the NPWT system. The audio signals are obtained using a microphone, wherein the microphone is a part of a mobile device. A processor is used to determine whether the audio signals include components having frequencies corresponding to a predetermined range of frequencies and assess, based on the components having frequencies corresponding to the predetermined range of frequencies, whether a leak is present in the NPWT system.

[0013] In example implementations of the present subject matter, a device for detecting leaks in a NPWT system comprises a processor and a machine-readable storage medium comprising instructionsexecutable by the processor to analyse a frequency spectrum of sound emanating from a NPWT system. The device determines whether the frequency spectrum comprises frequencies in a predetermined range of frequencies that corresponds to leakage of fluid from a component of the NPWT system and accordingly causes a notification of leakage of fluid from the component to be provided on a communication device associated with the NPWT system.

[0014] Example implementations of the present subject matter also include non-transitory computer- readable medium comprising instructions executable by a processing resource to analyse audio signals captured by a microphone of a mobile device to determine whether the audio signals include frequency components indicative of a leak in a NPWT system. The instructions further cause the processing resource to determine whether a sound intensity associated with the frequency components indicative of the leak is above a preset threshold and cause a notification of the leakage to be provided on the mobile device on determining the sound intensity associated with the frequency components indicative of the leak to be above the preset threshold.

[0015] The example techniques for detecting leaks in a NPWT system involve analysing audio signals emanating from the NPWT system to determine whether the audio signals include frequency components indicative of a leak in the NPWT system. Since the techniques for detecting leaks of the present subject matter rely on analysis of frequency spectrum of sound emanating from the NPWT systems, they may be more accurate than general techniques that rely on measuring intensity of the sound emanating from the NPWT systems, given that intensity of the sound is often not clearly detected in presence of background noises. Even if an attempt to quieten such background noises is made, in case of a NPWT system, the sound generated by the pump of the NPWT system cannot be eliminated and the accuracy of the measured intensity of the sound may not be assured.

[0016] In accordance with example implementations of the present subject matter, the audio signals may be captured using a microphone of a mobile device, thereby avoiding use of cost-intensive leak detection devices.

[0017] Example embodiments of the present subject matter also provide for identification of the location of the detected leak by determining a position of the microphone in reference to a component of the NPWT system at an instance at which the frequency components associated with the leak in the NPWT system occur in the audio signals.

[0018] Accordingly, the example techniques to detect leaks in NPWT systems described herein provide for detection of leaks with enhanced accuracy and without the use of cost-intensive leak detection devices. These techniques aid patients and medical professionals in detection as well as identification of location of leaks without the help of technical support in a time efficient and hassle- free manner, to be able to seal the leaks such that the treatment can progress without disruptions.BRIEF DESCRIPTION OF DRAWINGS

[0019] The detailed description is described with reference to the accompanying figures. It should be noted that the description and figures are merely examples of the present subject matter and are not meant to represent the subject matter itself.

[0020] Fig. 1 illustrates a device to detect leaks in negative pressure wound therapy (NPWT) systems, according to an example implementation of the present subject matter.

[0021] Fig. 2 illustrates a system for detecting leaks in a NPWT system, in accordance with an example implementation of the present subject matter.

[0022] Fig. 3 illustrates a device for detecting leakage of fluid from a component of a NPWT system, in accordance with another example implementation of the present subject matter.

[0023] Fig. 4 illustrates a method to detect leakage of fluid from a component of a NPWT system, in accordance with another example implementation of the present subject matter.

[0024] Fig. 5 illustrates a method for detection of leaks in a NPWT dressing of a NPWT system, according to an example of the present subject matter.

[0025] Fig. 6 illustrates a method for detection of leaks in a NPWT system, according to another example of the present subject matter.

[0026] Fig. 7 illustrates a method for identifying location of a leak in a component of a NPWT system, according to an example of the present subject matter.

[0027] Fig. 8 illustrates a method for identifying location of a leak in a NPWT dressing of a NPWT system, in accordance with an example implementation of the present subject matter.

[0028] Fig. 9 illustrates a computing environment for detection of leaks in a NPWT system, according to an example implementation of the present subject matter.

[0029] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and / or implementations consistent with the description, however, the description is not limited to the examples and / or implementations provided in the drawings.DETAILED DESCRIPTION

[0030] Example techniques to detect leaks in negative pressure wound therapy (NPWT) systems are described herein. In accordance with example implementations of the present subject matter, techniques for detecting leaks in a NPWT system involve analysing audio signals emanating from the NPWT system to determine whether the audio signals include frequency components indicative of a leak in the NPWT system.

[0031] Example embodiments of the present subject matter comprise determining a range of frequencies corresponding to leakage of fluid from various components of NPWT systems, for example, by way of experiments. In an example, a respective range of frequency associated with leakage of fluid from the components of a NPWT system, such as NPWT dressing, a tubing, a connector or a trackpadof the NPWT system may be predetermined. Such a range may serve as a reference for detection of leakage of fluid from the corresponding component.

[0032] In an example implementation, the present subject matter also enables identification of location of a leak detected in the NPWT system. Identification of the location of the detected leak is enabled by real-time processing of the audio signals emanating from the NPWT system, for example, to determine a real-time position of the microphone in reference to a component of the NPWT system at an instance at which the frequency components associated with the leak are detected.

[0033] Accordingly, the example techniques described herein enable users to detect leaks in NPWT systems as well as to identify corresponding locations of leaks in an accurate and easy manner.

[0034] The above techniques are further described with reference to Fig. 1 to Fig. 9. It should be noted that the description and the figures merely illustrate the principles of the present subject matter along with examples described herein and should not be construed as limiting the present subject matter. It is thus understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and implementations of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0035] Fig. 1 illustrates a device 100 to detect leaks in NPWT systems (not shown in Figure 1), according to an example implementation of the present subject matter.

[0036] Examples of the device 100 include a variety of electronic devices that may be used for processing audio signals emanating from a NPWT system to detect a leak. Examples of the device 100 may include but are not limited to, computing devices, such as servers, desktop computers, and personal computers. The device 100 may be a mobile device, such as a smartphone, personal digital assistants (PDA), tablet or a laptop in an example. In some examples, the device 100 may also be a part of a NPWT system. For example, the device 100 may be a therapy device of the NPWT system, which, among other things, allows pressure settings to be set for the NPWT system and controls a pump of the NPWT system according to such settings.

[0037] The device 100 includes processor(s) 102 and a machine-readable storage medium 104 which is coupled to, and accessible by, the processor 102. The processor(s) 102 may be implemented as microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and / or any devices that manipulate signals based on operational instructions. Among other capabilities, the processor(s) 102 is configured to fetch and execute computer-readable instructions including instructions stored in the machine-readable storage medium. The machine-readable storage medium may include non-transitory computer-readable medium including, for example, volatile memory (e.g., RAM), and / or non-volatile memory (e.g., EPROM, flash memory, etc.).

[0038] The processor 102 may fetch and execute instructions 106. In one example, as a result of the execution of the instructions 106, the device 100 may analyze a frequency spectrum of sound emanating from the NPWT system to detect a leak in the NPWT system. In the present implementation of subject matter, the sound emanating from the NPWT system may or may not be captured by the device 100 itself. For instance, in embodiments where the device 100 is a mobile device, such as a smartphone, that may incorporate a microphone to capture the sound emanating from the NPWT system, the device 100 may capture the sound and further analyze the captured sound to detect the leak.

[0039] In embodiments where the device 100 is a device that may not incorporate a microphone or may not be in proximity to the NPWT system so as to capture the sound, the device 100 may receive the sound captured by any microphone and analyse the received sound to detect the leak. In an example, the device 100 may be a remote server, such as a server implemented by a manufacturer of the NPWT system that may receive, from a mobile device located near the NPWT system, the sound as captured by a microphone of the mobile device and analyse the received sound to detect the leak. In such embodiments, the device 100 may include instmctions that cause the device 100 to receive audio data corresponding to the sound emanating from the NPWT system from external sources to process the audio data for detection of leaks.

[0040] For the device 100 to detect the leak in the NPWT system, the instructions 106 may be executed to generate a frequency spectrum of the sound emanating from the components of NPWT system. The device 100 may implement audio analysis techniques, such as Fourier transformation to generate the frequency spectrum of the sound emanating from the components of NPWT system. Based on the frequency spectrum, the instructions may be executed to determine whether the frequency spectrum comprises frequencies in a predetermined range of frequencies corresponding to leakage of fluid from the components of NPWT system.

[0041] In an example, data pertaining to the predetermined range of frequencies that corresponds to leakage of fluid from the NPWT systems may be provided to the processor, for example, to be used as a reference to determine whether the frequency spectrum comprises frequencies corresponding to the leakage. In an embodiment, the data pertaining to the predetermined range of frequencies may be stored in the machine-readable storage medium or in an external memory component accessible by the processor 102. The data pertaining to the predetermined range of frequencies that corresponds to leakage of fluid from the NPWT systems may be based on experiments conducted to determine acoustic characteristics of sound produced due to leakage of fluid from the NPWT systems. In an example, the predetermined range of frequencies is between 5 kHz to 20 kHz. If the analyzed frequency spectrum comprises frequencies that lie in the predetermined range of frequencies, the device 100 may cause a notification of leakage of fluid from a component of the NPWT system to be provided on a communication device (not shown) associated with the NPWT system.

[0042] The communication device associated with the NPWT system may be a device accessible to a patient being treated by the NPWT system in which the leak is detected or a device accessible to amedical professional or caregiver of the patient. The communication device may be the device 100 itself, in an example. However, in examples where the communication device associated with the NPWT system is external to the device 100, the device 100 may incorporate communication techniques to provide the notification to the communication device. In an example, the device 100 may be the above-described mobile device incorporating the microphone and may provide the notification of the leak to a communication device, such as the remote server of the manufacturer of the NPWT system, by communicating with the remote server over the internet.

[0043] The notification on the communication device indicates presence of the leakage to a user and may prompt the user to take a corrective measure, such as sealing of the leakage.

[0044] Reference is now made to Fig. 2 that illustrates a system 200 for detecting leaks in a NPWT system 202, in accordance with an example implementation of the present subject matter.

[0045] The NPWT system 202 may include several components that may work in conjunction to apply and maintain a negative pressure over a wound 204 of a patient to be treated. For example, the NPWT system 202 includes a NPWT dressing 206 that is applied to the wound site such that a sealed space is created around a periphery of the wound 204 for application of the negative pressure. The NPWT dressing 206 may be of non-permeable or semi-permeable material to provide an optimal healing environment and act as a barrier to external contaminants.

[0046] The NPWT dressing 206 is provided with a trackpad 208 and a tubing 210 that connects the NPWT dressing 206 to a pump 212 that creates the negative pressure. The trackpad 208, when the pump 212 is operational, is to distribute negative pressure thus developed by the pump 212. In addition, the trackpad 208 also enables channeling exudates and other fluids away from the wound site. The pump 212 may be incorporated in or may be associated with a therapy device 214 that controls the pump 212 such that the pump 212 operates to create the negative pressure in accordance with user inputs. The therapy device 214 may include, for example, user interfaces to allow users to provide inputs to set the negative pressure. The therapy device 214 may also allow users to provide inputs to control the pump 212 for causing the pump 212 to apply the negative pressure either continuously or intermittently.

[0047] The NPWT system 202 may include one or more connectors 216-1, 216-2 to provide air-tight connection between the various components of the NPWT system 202. For example, the connectors 216-1, 216-2 may be used to connect the trackpad 208 and the tubing 210; and the tubing 210 and the pump 212, respectively.

[0048] As discussed, during a course of the treatment, leakages may develop in one or more of the various components of the NPWT system 202. For example, a leak may occur in the NPWT dressing 206 owing to an opening in the adhesive layer of the NPWT dressing 206 that secures the NPWT dressing 206 to areas around the wound 204 to form the air-tight sealing. Similarly, a leak may occur in the tubing 210 or the connectors 216-1, 216-2 due to movement of the patient that may tug these components. Such leakages in the NPWT system 202 are required to be identified and sealed.

[0049] In accordance with example implementations of the present subject matter, a frequency spectmm-based leak detection engine 218 of the system 200 is operable to detect the leaks based on the sound emanating from the components of the NPWT system 202. In the example embodiment of the system 200 depicted in Fig.2, frequency spectmm-based leak detection engine 218 is incorporated in a mobile device 220, such as a smartphone. The frequency spectrum-based leak detection engine 218 is hereinafter, referred to as leak detection engine 218 for simplicity.

[0050] In an example, the leak detection engine 218 may be implemented as a combination of hardware and programming (for example, programmable instructions) to implement certain functionalities in the mobile device 220. In the examples described herein, such combinations of hardware and programming may be implemented in several different ways. Among other capabilities, the leak detection engine 218 may be configured to fetch and execute computer-readable instructions stored in a memory (not shown in Fig. 2) of the mobile device 220.

[0051] To detect leaks in the NPWT system 202, the leak detection engine 218 is operable to analyze the sound emanating from the NPWT system 202. In an example, the sound emanating from the NPWT system 202 may be captured by a microphone (not shown) of the mobile device 220. The leak detection engine 218 is configured to generate a frequency spectrum of the sound captured from the NPWT system 202. The leak detection engine 218 is further configured to assess if the frequency spectrum comprises frequencies in a predetermined range of frequencies. The predetermined range of frequencies corresponds to frequencies associated with leakage of fluid from NPWT systems may be determined by collecting experimental data pertaining a number of leaks in multiple NPWT systems, for example. If frequencies corresponding to the predetermined range of frequencies are present in the sound emanating from the NPWT system 202 as captured by the microphone, leak detection engine 218 detects a leak in the NPWT system 202.

[0052] While the example embodiment depicted in Fig 2 shows the mobile device 220 to include the leak detection engine 218, as discussed previously, the leak detection engine 218 can be incorporated in a variety of electronic devices, including, for example, the therapy device 214 or a remote server 222 that may be hosted by the manufacturer of the NPWT system 202, for instance.

[0053] In embodiments where the leak detection engine 218 resides in devices other than the mobile device 220 incorporating the microphone that records the sound emanating from the NPWT system 202, it will be understood that such other devices incorporate techniques to communicatively couple with the mobile device 220 to receive audio data corresponding to the captured sound. Accordingly, to detect leaks in the NPWT system 202, the leak detection engine 218, when implemented in the therapy device 214 may receive audio data corresponding to the sound captured by the microphone of the mobile device 220, from the mobile device 220.

[0054] The communication between the mobile device 220 and the leak detection engine 218 of the therapy device 214 may be either through a wired communication channel or a wireless communication channel. Examples of wired communication may include electrical cables made of electricallyconducting material that may allow communication of information or data between the mobile device and the leak detection unit. The communication channel may be implemented through a wireless protocol, examples of which include Bluetooth® or Wi-Fi. The present examples are only indicative and other forms of communication modes (wired or wireless) would also be within the scope of the present subject matter.

[0055] Similarly, the leak detection engine 218 when implemented in the remote server 222, may receive audio data corresponding to the sound captured off the NPWT system 202 by other devices for processing to detect the leak. For example, the sound emanating from the NPWT system 202 may be captured using the microphone of any mobile device in proximity of the NPWT system 202, such as mobile device 220. The leak detection engine 218 implemented in the remote server 222 may be communicatively coupled with the mobile device 220 to receive the audio data.

[0056] In an example, the mobile device 220 may communicate with the leak detection engine 218 over a network 224 to provide the audio data to the leak detection engine 218. The network 224 may be a single network or a combination of multiple networks and may use a variety of different communication protocols. The network 224 may be a wireless or a wired network, or a combination thereof. Examples of such individual networks include, but are not limited to, Global System for Mobile Communication (GSM) network, Universal Mobile Telecommunications System (UMTS) network, Personal Communications Service (PCS) network, Time Division Multiple Access (TDMA) network, Code Division Multiple Access (CDMA) network, Next Generation Network (NGN), Public Switched Telephone Network (PSTN). Depending on the technology, the communication network 224 includes various network entities, such as gateways, routers; however, such details have been omitted for the sake of brevity of the present description.

[0057] The mobile device 220 may transmit the audio data to the remote server 222 using a variety of techniques, such as uploading a file comprising the audio data to an IP address of the remote server 222. In such example implementations, the mobile device 220 may serve to capture the sound and transmit the same to the remote server 222 where the leak detection engine 218 would further process it, for example, using processing resource of the remote server 222 to detect the leak. Some example implementations of the leak detection engine 218 may be analogous to a thin client of the leak detection engine 218 residing in a mobile device incorporating a microphone that may be positioned in proximity of the NPWT system 202 to record the sound thereof, and the thick client residing in the remote server 222 to receive and further process audio data corresponding to such sound for leak detection.

[0058] Accordingly, example implementations of the leak detection engine 218 may include implementing the leak detection engine 218 as a web-based application that may be accessible via the internet by any electronic device (not shown) that may execute an internet browser. The electronic device may be, for example, the mobile device 220 that may directly capture the sound arising from the NPWT system 202. However, it is also possible that the electronic device may not capture the sound arising from the NPWT system 202 itself and rather receive audio data corresponding to the sound fromanother device that recorded the sound. Thus, embodiments, such as one where the sound arising from the NPWT system 202 is recorded by a smartphone of a patient and shared with a technician of the NPWT system 202 who may in turn provide it to the remote server 222 or any other device hosting the leak detection engine 218 may also be possible.

[0059] In examples where the leak detection engine 218 is a web-based application, the leak detection engine 218 may be made accessible via the internet through a variety of mechanisms, including, for example, by use of a machine-readable code. The machine-readable code, examples of which include but are not limited to a QR code, may comprise a web address or a Uniform Resource Locator (URL) of the leak detection engine 218. The machine-readable code may be affixed on the therapy device 214 in one example. Scanning the machine-readable code, using a camera of a smartphone, for example, the mobile device 220, may open a webpage hosting the leak detection engine 218 to enable the mobile device 220 to provide the audio data to the leak detection engine 218.

[0060] In example embodiments, the machine-readable code may also be embedded with additional information such as an identifier of the therapy device 214 and a patient ID associated with the therapy device 214. Such additional information may also be provided to the leak detection engine 218 by the mobile device 220 by use of the machine-readable code. Making such additional information available to the leak detection engine 218 may have several uses. For example, if the leak detection engine 218 detects a leak in a NPWT system, such as the NPWT system 202, based on the audio data captured corresponding to the NPWT system 202, the leak detection engine 218 may notify a user, for example, a patient or a technician, associated with the NPWT system 202. For the purpose, contact information corresponding to the NPWT system 202 may be made available to the leak detection engine 218. For instance, the contact information corresponding to the NPWT system 202 may be provided to the leak detection engine 218 by a user through the webpage hosting the leak detection engine 218. In another example, the contact information corresponding to the NPWT system 202, such as contact number(s) of a call centre set-up for the NPWT system 202, may be included in the machine-readable code for use by the leak detection engine 218.

[0061] In an example, the leak detection engine 218, for example, the leak detection engine 218 residing the remote server 222, may store data relating to acoustic properties of the sound emanating from the NPWT system 202 in cases where the leak detection engine 218 detects a leak in the NPWT system 202. The remote server 222 may store the frequency and intensity of the sound emanating from the leak, for example. Collating such data relating to the NPWT system 202 and other devices similar to NPWT system 202, may, over a period of time, make available with the remote server 222, a volume of data relating to acoustic properties of the sound emanating from leaks in NPWT systems. Such data may be used for various purposes, including, for example, analyzing the data to further refine the predetermined range of frequencies corresponding to leakage of fluid from the components of NPWT systems.

[0062] Fig. 3 illustrates a device 300 for detecting leakage of fluid from a component of a NPWT system in accordance with another example implementation of the present subject matter. Examples of the device 300 include servers, desktop computers, laptops, and smartphones. Examples of the device 300 also include NPWT devices. In example implementations, the device 300 may be similar to the device 100 described above in reference to Fig.1. For ease of explanation of Fig. 3, the device 300 may be considered to be a mobile device incorporating a microphone.

[0063] The device 300, among other things, includes and a processor 102, memory 302, interface(s) 304, and engine(s) 306. The memory 302 may include any computer-readable medium including, for example, volatile memory (e.g., RAM), and / or non-volatile memory (e.g., EPROM, flash memory, etc.). The interface 302 may include a variety of software and hardware interfaces that allow the device 300 to interact with other devices, such as a therapy device of a NPWT system, such as the aboveexplained NPWT system 202; a remote server, such as the above-explained remote server 222; or other input / output (I / O) devices that may be used to provide inputs, such as audio data to the device 300.

[0064] The engine(s) 306 may be implemented as a combination of hardware and programming (for example, programmable instructions) to implement certain functionalities of the engine(s) 306. In the examples described herein, such combinations of hardware and programming may be implemented in several different ways. For example, the programming for the engine(s) 306 may be processorexecutable instructions stored on a non-transitory computer-readable storage medium, and the hardware for the engine(s) 306 may include a processing resource (for example, implemented as either a single processor or a combination of multiple processors), to execute such instructions. In the present examples, the computer-readable storage medium may store instructions that, when executed by the processing resource, implement engine(s) 306. In such examples, the device 300 may include the computer-readable storage medium storing the instructions and the processing resource to execute the instructions, or the computer-readable storage medium may be separate but accessible to the device 300 and the processing resource.

[0065] In other examples, engine(s) 306 may be implemented by electronic circuitry. The engine(s) 306 may include a communication engine 308 and a leak detection engine 310. The leak detection engine 310 may be similar to the above-described leak detection engine 218 and, in an example, may include a location identification engine 312. In an example, the engine(s) 306 may also comprise other engine(s) 314 that supplement functions of the device 300.

[0066] Data 316 of the device 300 serves, amongst other things, as a repository for storing data that may be fetched, processed, received, or generated by the engine(s) 306. In the illustrated example, the data 316 comprises audio data 318, frequency value data 320, intensity value data 322, and video data 324. The data 316 also comprises other data 326 corresponding to the other engine(s) 314.

[0067] The communication engine 308 may be operable to receive audio data captured by a microphone, the audio data corresponding to the sound emanating from the NPWT system 202. In cases where the microphone is a part of the device 300, such as a microphone 328, the communication engine308 may interact with the microphone 328 via the interfaces 304 to obtain the audio data. In cases where the microphone is external to the device 300, the communication engine 308 may use the interfaces 304 to obtain the audio data captured by such external microphone.

[0068] The audio data obtained by the communication engine 308 may be stored in the data 316 of the device 300 as audio data 318. The audio data obtained by the communication engine 308 may be used by the leak detection engine 310 for detecting leakage of fluid from one or more components of the NPWT system 202. For the purpose, the leak detection engine 310 may use the above-described frequency-spectrum based detection method, in one example.

[0069] To enable the leak detection engine 310 to detect leakages in any of the components of the NPWT system 202 a predetermined range of frequencies, corresponding to leakage of fluid from the components of NPWT systems, may be made accessible to the leak detection engine 310. In example embodiments, the leak detection engine 310 may be operable to detect leaks in the NPWT dressing 206, tubing 210, one or more connectors 216-1, 216-2, or trackpad 208 of the NPWT system 202. Accordingly, in an example, the communication engine 308 may obtain data pertaining to respective range of frequencies corresponding to leakage of fluid from the components, i.e., NPWT dressings, tubings, connectors, and trackpads of NPWT systems. The respective range of frequencies made available to the leak detection engine 310 by the communication engine 308 may serve as a reference for detection of the leakage in the NPWT dressing 206, tubing 210, connector 216-1, 216-2 and / or trackpad 208 of the NPWT system 202.

[0070] An example predetermined range of frequencies corresponding to leakage of fluid from tubings, connectors and trackpads of the NPWT systems may be 10-15kHz while an example range of frequency corresponding to leakage of fluid from NPWT dressings may be 15-20kHz or 5-20kHz. As will be understood, other ranges may also be defined. For example, one or more ranges within the range or close to the range of 5-20kHz may be defined corresponding to different types of NPWT systems.

[0071] In an example, the data pertaining to respective range of frequencies corresponding to the different components of NPWT systems may be stored as frequency value data 320 in the data 316 of the device 300. In the example depicted in Fig. 3, the data pertaining to respective range of frequencies corresponding to leakage of fluid from the components of NPWT systems has been shown to reside internal to device 300. However, examples where the frequency value data 320 may reside in an external database accessible to the device 300, for example, an external server implemented for users of NPWT systems, are also possible.

[0072] The leak detection engine 310 may cause a notification of leakage of fluid from the component to be provided on a communication device associated with the NPWT system 202 if the frequency spectrum comprises frequencies in the predetermined range of frequencies. In an example, alert indicative of presence of the leak to be generated on the device 300. The alert, in one example, may be in the form of a haptic feedback wherein a haptic output of the device 300 may be triggered by the leak detection engine 310 through the interfaces 304.

[0073] In addition to determining whether the frequency spectrum of the audio data obtained by the communication engine 308 includes frequencies in the predetermined range of frequencies for detecting the leaks, the leak detection engine 310 may implement further techniques, for example, to enhance the accuracy of the detection of the leaks.

[0074] In accordance with an implementation of the present subject matter, the leak detection engine 310 may compute sound intensity of the audio data obtained by the communication engine 308. For instance, the leak detection engine 310 may compute sound intensity of the portion of the frequency spectrum of the sound that comprises the frequencies in the predetermined range of frequencies. The leak detection engine 310 may determine the sound intensity to be above a preset threshold value to cause the notification or alert.

[0075] In an example, alike the predetermined range of frequencies corresponding to leakage of fluid from the components of NPWT systems, the preset threshold may be deduced by way of analysis of the characteristics of sound emanating from leaks in NPWT systems. The preset threshold may be a value of sound intensity that the sound emanating from leaks in NPWT systems typically exhibits. In an example, the preset threshold may be 30dB. The preset threshold may be stored as intensity value data 322 in data 316. The leak detection engine 310 may retrieve the intensity value data 322 for checking the sound intensity to be above the threshold. Checking that the audio data corresponding to the sound emanating from the NPWT system 202 has the sound intensity of at least the preset threshold, allows the leak detection engine 310 to detect the leaks more accurately.

[0076] In example implementations, the device 300 may further provide for identification of a location of the leak. For instance, having detected the presence of a leak in a component of the NPWT system 202, the leak detection engine 310 may trigger the location identification engine 312 to identify a component in which the leak is located. Accordingly, in an example, the location identification engine 312 may identify the leak to be present in the connector 216-1 or 216-2, tubing 210 or dressing 206 of the NPWT system 202 to aid sealing of the leak. Furthermore, the location identification engine 312 may also identify the location of the leak in a more localized manner. For instance, the location identification engine 312 may identify a part of a perimeter of the NPWT dressing 206 where the leak may exist.

[0077] The location identification engine 312 may corelate a portion of the audio data where the frequencies in the predetermined range of frequencies are detected to a position of the microphone that records the sound emanating from the NPWT system 202 to identify a location of the leak. For example, the location identification engine 312 may process audio data corresponding to the sound emanating from the NPWT system 202 in real-time to identify the location of the leak. In embodiments, to enable the location identification engine 312 to identify the location of the leak in real-time, the audio data corresponding to the sound emanating from the NPWT system 202 may be obtained by the communication engine 308 in real-time. Accordingly, in examples, the communication engine 308 may use the interfaces 304 to receive the audio data from the microphone 328 in real-time.

[0078] The microphone 328 may be moved with respect to the NPWT system 202 to capture the sound emanating therefrom. For example, referring to Fig. 2 for explanation, the microphone 328 may be moved around the boundary of the NPWT dressing 206 in a circular manner by a user recording the sound. The microphone 328 may be brought close to the trackpad 208 to capture the sound emanating therefrom, if any. Similarly, the microphone 328 may be moved along the length of the tubing 210 and be placed beside the connectors 216-1 or 216-2 to capture any sound a leak in these components may generate.

[0079] As the user moves the microphone 328 along the components of the NPWT system 202, the communication engine 308 may obtain the audio data corresponding to the sound emanating therefrom in real-time and the location identification engine 312 may process the corresponding audio data in realtime to identify the location of the leak. For the purpose, the location identification engine 312 may detect the position of the microphone 328 relative to a component of the NPWT system 202 at an instance at which frequencies in the predetermined range of frequencies are detected in the sound that the microphone 328 captures. The NPWT system 202 thus determines the position of the microphone 328 at said instance to be the location in the NPWT system 202 where the leak may be located.

[0080] To indicate the location of the leak in the NPWT system 202, the location identification engine 312 may use the interfaces 304 either directly or through the communication engine 308 to generate visual feedback on a display 330 of the device 300. In an example, the display 330 of the device 300 or a part thereof may turn red, at the location of the leak. For instance, as the microphone 328 is moved about the NPWT system 202, the display 330 may project a red-coloured icon when the microphone 328 is at the position where the leak has been identified. At a position close to the location of the leak by a predetermined distance, the display 330 may project, for example, a yellow-colored icon to indicate that the leak is in proximity to the current position of the microphone 328. Likewise, as the microphone 328 is moved away from the location of the leak by a predetermined distance, the display 330 may project, for example, a green-colored icon to indicate that the current position of the microphone 328 may not be close to where the leak is present. Similar to the visual feedback, in an example, haptic feedback with varying degrees of vibrations indicative of proximity to the location of the leak is also possible.

[0081] In some implementations, the device 300 may also provide a visual indication of the location of the leak in the NPWT system 202. For example, the location identification engine 312 may cause the location of the leak along a perimeter of the NPWT dressing 205 to be shown on the display 330 of the device 300. The location identification engine 312 may incorporate video processing techniques to provide such visual indications that display the identified location of the leak.

[0082] In an example embodiment, to provide a visual indication of the identified location of the leak the NPWT dressing 205 of the NPWT system 202, the communication engine 308 may receive audio data captured by microphone 328 as the microphone 328 is moved along a perimeter of the NPWT dressing 206. The communication engine 308 may also receive video data corresponding to theperimeter of the NPWT dressing 206. The video data may be synchronized in time with the audio data. Thus, the video data comprises views of portions of the NPWT dressing 206 along the perimeter that correspond to the different position of the microphone 328 as the microphone 328 is moved along the perimeter to capture the sound emanating from the NPWT dressing 206.

[0083] In an example, the video data corresponding to the perimeter of the NPWT dressing 206 may be captured through a camera of 332 of the device 300. For instance, the location identification engine 312 may use the interfaces 304 either directly or through the communication engine 308 to actuate the camera of 332 to obtain the video data. In an example, the camera of 332 may be actuated to record the video data simultaneously with the actuation of the microphone 328 to capture the sound emanating from different portions of the NPWT dressing 206. The communication engine 308 may, in one example, store the video data corresponding to the perimeter of the NPWT dressing 206 as the video data 324 in data 316 of the device 300.

[0084] The location of the leakage along the perimeter of the NPWT dressing 206 may be identified based on the video data 324 in conjunction with the audio data. The location identification engine 312 may identify a portion of the video data corresponding to a portion of the audio data where the predetermined frequencies indicative of leak from NPWT dressings are detected. The identified portion of the video data may be provided as a visual indication of the location of the leak along the perimeter of the NPWT dressing 206 on the display 330 of the device 300.

[0085] Fig. 4 illustrates a method 400 to detect leakage of fluid from a component of a NPWT system, in accordance with another example implementation of the present subject matter. The method 400 may be implemented in, for example, the above-explained mobile device 220, therapy device 214 or remote server 222. Although the method 400 and may be implemented in a variety of devices, for the ease of explanation, the present description of the example method 400 is provided in reference to the abovedescribed mobile device 220.

[0086] The order in which the method 400 is described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method 400, or an alternative method. Furthermore, the method 400 may be implemented by a processor(s) or computing device(s) through any suitable hardware, non-transitory machine-readable instructions, or combination thereof.

[0087] It may be understood that blocks of the method 400 may be performed by programmed computing devices. The blocks of the method 400 may be executed based on instructions stored in a non-transitory computer-readable medium, as will be readily understood. The non-transitory computer- readable medium may include, for example, digital memories, magnetic storage media, such as magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media.

[0088] At block 402, the method 400 comprises receiving audio data corresponding to the sound emanating from a NPWT system. In an example, the audio data may be captured by a microphone of a mobile device, such as the mobile device 220 and may be received by the processor of the mobile device220 for analysing, at block 404, a frequency spectrum of the received audio data. Example implementations, where the audio data may be captured by the microphone of the mobile device 220 and may be received and processed, in accordance with the method 400, by another processor, such as the processor of the therapy device 214, are also possible.

[0089] Based on the analysis of the frequency spectrum of the received audio data carried out at block 404, at block 406, it is determined whether the frequency spectrum comprises frequencies in a predetermined range of frequencies corresponding to leakage of fluid from a component of the NPWT system. As discussed previously, if the audio data comprises frequencies in the range of 5 -20kHz, it may be determined that a leak is present in the NPWT system.

[0090] Accordingly, based on the analysis of the frequency spectrum, at block 408, a notification of leakage of fluid from the component may be provided to a communication device associated with the NPWT system. For example, the processor of the mobile device 220, may cause the notification to be generated on a user interface of the mobile device 220. In example implementations where the audio data is received and processed by the processor of the therapy device 214, the therapy device 214 may cause the notification to be generated on the mobile device 220 or any other communication device, such as a computer located at a site of a medical professional. Likewise, in examples where the audio data captured by the microphone of the mobile device 220 is received and processed by the remote server 222, by the remote server 222 may cause the notification to be generated on a communication device, such as the mobile device 220, the therapy device 214 or any other device accessible to a medical professional.

[0091] Fig. 5 illustrates a method 500 for detection of leaks in a NPWT dressing of a NPWT system, according to an example of the present subject matter.

[0092] Alike the method 400, the method 500 may also be implemented in a variety of devices, including, for example, the mobile device 220, therapy device 214 or remote server 222. The blocks of the method 500 may be performed by programmed computing devices. The blocks of the method 500 may be executed based on instructions stored in a non-transitory computer-readable medium, in any order, as will be readily understood.

[0093] At block 502, the method 500 comprises obtaining audio signals corresponding to the sound emanating from a NPWT dressing of a NPWT system, that provides a sealed space for application of negative pressure. In an example, the audio data may be captured by a microphone of a mobile device, such as the mobile device 220. The audio signals captured by the microphone, may be obtained by a processor of any device, such as the mobile device 220, therapy device 214 or remote server 222 and, at block 504, the processor may determine whether the audio signals include components having frequencies corresponding to a predetermined range of frequencies. In an example, the processor may determine whether the audio signals include components having frequencies in the range of 15 -20kHz.

[0094] At block 506, the processor may assess, based on the components having frequencies corresponding to the predetermined range of frequencies, whether a leak is present in the NPWTdressing. Based on the assessment made at block 506, the processor may take further measures, such as causing an alert indicative of the leak present in the NPWT dressing to be generated, for example, at the mobile device 220.

[0095] Fig. 6 illustrates a method 600 for detection of leaks in a NPWT system, according to another example of the present subject matter. Although the method 600 may be implemented in a variety of devices, such as the mobile device 220, therapy device 214 or remote server 222, for the ease of explanation, the present description of the example method 600 is provided in reference to the abovedescribed mobile device 220.

[0096] The method 600 initiates at block 602, where a potential leak in a NPWT system is determined. In an example, the mobile device 220 may detect the potential leak in the NPWT system, via an application executing on the mobile device 220. The application may be notified of the potential leak by the therapy device 214 or the remote server 222. In the event of detection of the potential leak, at block 604, a prompt to capture sound emanating from the NPWT system may be generated on the mobile device 220. For example, the application may cause the prompt, for instance, in the form of a message to be displayed on the mobile device 220. The message may include instructions for a user to capture the audio data. In example embodiments, the message may include pictorial representation depicting how the user may orient a microphone of the mobile device to capture the audio data.

[0097] In response to the prompt, at block 606, audio data captured by the mobile device is received, for example, by the application. The application may have instructions executable by the processor of the mobile device 220 for analysis of acoustic characteristics of the captured audio data. At block 608, it is assessed whether the audio data includes components having frequencies corresponding to a predetermined range of frequencies. As discussed previously, the predetermined range of frequencies is 5-20kHz, in an example, that is associated with sound arising from a leakage of fluid from a component of the NPWT system. If the audio data does not comprise frequency components in the predetermined range, at block 610, it may be determined that no leak is present in the NPWT system, i.e., the ‘no’ branch of the block 608. However, if the audio data does comprise frequency components in the predetermined range, the method 600 may implement further steps to confirm the potential leak.

[0098] Accordingly, the method 600 may proceed to block 612, i.e., the ‘yes’ branch of the block 608, where an amplitude of the respective components in the predetermined range of frequencies is computed and at block 614, the component with the highest amplitude may be identified from amongst those components. At block 616, it is determined whether the identified highest amplitude is above a threshold.

[0099] The method 600 may assess the amplitude of the captured sound in addition to analysing its frequency spectrum, for instance, to enhance accuracy of confirmation of the potential leak. At the same time, to economize the time and processing resource that may be involved in the method 600, the method may compute and assess the amplitude of the components in the predetermined range offrequencies alone and not the complete captured audio data. Thus, at block 618, presence of the potential leak is confirmed upon having identified that the highest amplitude is above the threshold.

[0100] Fig. 7 illustrates a method 700 for identifying location of a leak in a component of a NPWT system, according to an example of the present subject matter and Fig. 8 illustrates a method 800 for identifying location of a leak in a NPWT dressing of a NPWT system, according to an example of the present subject matter.

[0101] Similar to the previously explained methods, the order in which the methods 700 and 800 are described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method, or an alternative method. Similarly, the blocks of the methods 700 and 800 may also be executed based on instructions stored in a non-transitory computer-readable medium.

[0102] Referring to Fig. 7, at block 702, data pertaining to respective predetermined range of frequencies corresponding to leakage of fluid from components of NPWT systems may be obtained. In an implementation, an application executing on a mobile device, such as the mobile device 220 may obtain the data and store the same locally in the memory of mobile device 220, for example, at the time the application is installed in the mobile device 220. Such data may be used subsequently in case a leak is detected in a NPWT system associated with a user of the mobile device 220.

[0103] If a leak is suspected in the NPWT system, the user may capture the sound generated owing to the leak using a microphone of the mobile device 220. At block 704, audio signals corresponding to the sound captured by the user by moving the microphone along components of the NPWT system may be received in real-time and processed by the application. At block 706, it may be determined if the audio signals comprise frequency components in the predetermined range of frequencies to identify a leak in the NPWT system. As discussed previously, the application may include instructions executable by the processor for generation of the frequency spectrum of the audio signals, for instance, by performing Fourier transformation. The application may identify the leak if the frequency spectrum of the audio signals includes frequency components in the predetermined range of 5-20kHz.

[0104] Upon identifying presence of the leak, the method 700 may further determine where the leak is located within the NPWT system. For instance, the method 700 may identify if the leak is located in the NPWT dressing or the tubing of the NPWT system. Identifying the location of the leak enables a user to seal the leak promptly without having to take measures to locate the leak manually. For the purpose, the application may include instructions executable by the processor for corelating portions of the captured audio signals to positions of the mobile device with respect to the NPWT system for the duration that the audio signals are captured. The processing of the audio signals may be done in realtime or near real-time so that a time instance where the frequency components associated with the leak occur may be identified and corelated with the position of the mobile device at that instance to locate the leak.

[0105] Accordingly, in one example, to enable identification of the location of the leak, at block 708, an instance of occurrence of the frequency components corresponding to the predetermined range of frequencies is determined in real-time and, at block 710, the position of mobile device with respect to the NPWT system at the instance of occurrence of the frequency components is identified as a location of the leak in NPWT system.

[0106] Reference is now made to the method 800 for identifying a location of a leak in a NPWT dressing of a NPWT system, according to an example of the present subject matter. Similar to several of the previously described example methods, the method 800 may be implemented in a variety of electronic devices, for example, the mobile device 220, therapy device 214 or remote server 222. The present description of the example method 800 is provided in reference to the mobile device 220 merely to aid explanation.

[0107] At block 802, audio signals emanating from the NPWT dressing, captured by moving a microphone along a perimeter of the NPWT dressing is obtained. As will be readily understood, the microphone may be a part of the mobile device 220. Example implementations of block 802 of method 800 may be similar to the block 702 of the method 700 or block 502 of the method 500 where audio signals captured by a microphone other than the microphone of the mobile device 220 may be obtained for processing by a processor of another device, such as the therapy device 214.

[0108] At block 804, video data corresponding to the perimeter of the NPWT dressing is obtained. The video data is time-synchronized with the audio signals or captured simultaneously with the audio signals. In one example, the video data may be captured via a camera of the mobile device 220 simultaneously as the microphone of the mobile device 220 captures the audio signals such that time synchronized audio-video data is obtained by the processor of the mobile device 220. However, other implementations where the video data captured by other devices may be obtained for processing by a processor of another device, such as the therapy device 214 are also possible. Such separately captured audio and video data may be time synchronized for further processing. Example techniques such as synchronizing the audio-video data in time allow correlating a portion of the audio signals comprising frequencies corresponding to the predetermined range of frequencies to the position of mobile device in the video data to locate the leak. An example implementation of method 800 may involve assigning timestamps to the audio and video data for corelating them.

[0109] Accordingly, in one example implementation, at block 806, the audio signals captured by moving the microphone of the mobile device along the perimeter of the NPWT dressing is timestamped to allow, at block 808, timestamps associated with components of the audio signals that have the predetermined range of frequencies to be identified. Based on the timestamps assigned to portions of audio data where such components occur, the portions of the video data corresponding to the occurrence of these components is identified at block 810. Since the video data pertains to the perimeter of the NPWT dressing, the identified portion of the video data indicates the location of the leak along theperimeter of the NPWT dressing. Thus, based on the portion of the video data, the location of the leak along the perimeter of the NPWT dressing is determined, at block 812.

[0110] As will be understood, while the method 800 has been described in reference to the NPWT dressing, the techniques described in reference thereto, may be implemented to locate a leak in other components of the NPWT system. For instance, the techniques may be implemented to locate a leak in a tubing of the NPWT system. The microphone and camera of the mobile device may simultaneously capture audio and video data, respectively, corresponding to the sound emanating from the tubing. Using the synchronized audio-video data of the tubing, the portion of the audio having frequencies in the predetermined range may be corelated with the position of the microphone along the length of the tubing to locate the leak in the tubing in an example.

[0111] Fig. 9 illustrates an example computing environment 900 for detecting leaks in a NPWT system, according to an example implementation of the present subject matter. In one exemplary implementation, the computing environment 900 includes a processing resource 904 communicatively coupled to a non-transitory computer-readable medium 902 through a communication link 906. In an example, the processing resource 904 fetches and executes computer-readable instructions 912 from the non-transitory computer-readable medium 902.

[0112] For example, the processing resource 904 can be a processor of a mobile device, such as the mobile device 220, the therapy device 214 or the remote server 222. The non-transitory computer- readable medium 902 can be, for example, an internal memory device or an external memory device. In one implementation, the communication link 906 may be a direct communication link, such as one formed through a memory read / write interface. In another implementation, the communication link 906 may be an indirect communication link, such as one formed through a network interface. In such a case, the processing resource 904 can access the non-transitory computer-readable medium 902 through a network 908. The network 908 may be a single network or a combination of multiple networks and may use a variety of different communication protocols.

[0113] The processing resource 904 and the non-transitory computer-readable medium 902 may also be communicatively coupled to a data source(s) 910. The data source(s) 910 may, in an example, be used to store data pertaining to respective range of frequencies and intensity corresponding to leakage of fluid from various components of the NPWT system that may be generated based on experiments conducted to determine acoustic characteristics of sound produced due to leakage of fluid from such various components.

[0114] In an example implementation, the non-transitory computer-readable medium 902 includes a set of computer-readable instructions 912 that may, in one example, be executable by the processing resource 904 for analysing audio signals, corresponding to sound emanating from the NPWT system that may be captured by a microphone of a mobile device. Analysis may be carried out to determine whether the audio signals include frequency components indicative of a leak in the NPWT system. For the analysis, in an example, a frequency spectrum of the audio signals may be generated. The datapertaining to respective predetermined range of frequencies corresponding to leakage of fluid from various components of the NPWT system may be accessed from the data source(s) 910 and frequency of components of the audio signals, as determined based on the frequency spectrum, may be compared to respective predetermined range of frequencies. If the comparison reveals that the audio signals include frequency components having frequencies corresponding to a predetermined range of frequencies, the leak may be detected.

[0115] For audio signals that include frequency components indicative of a leak in the NPWT system, the non-transitory computer-readable medium 902 may include a set of instructions executable by the processing resource 904 to determine the sound intensity associated with such components and assess if the sound intensity is above a preset threshold. As explained previously, in an example, the sound intensity associated with the frequency components indicative of the leak may be the highest sound intensity attained by the frequency components indicative of the leak or, in other words, the highest sound intensity from amongst the components of the audio signals whose frequencies correspond to the predetermined range of frequencies. In a manner similar to the predetermined range of frequencies corresponding to leakage of fluid from various components of the NPWT system, the data source(s) 910 may also store preset threshold values for sound intensity associated with leakage of fluid from these components.

[0116] Further, the non-transitory computer-readable medium 902 may also include instructions that may, in one example, be executable to cause a notification of the leakage to be provided on the mobile device on determining the sound intensity associated with the frequency components indicative of the leak to be above the preset threshold. In an example, determining the sound intensity associated with the frequency components indicative of the leak to be above the preset threshold ensures higher accuracy in detecting leaks in the NPWT systems.

[0117] In an example, the above-described process of detecting a leak in a NPWT system may be initiated upon receiving a notification of a potential leak in the NPWT system. For example, a potential leak in the NPWT system may be detected by the therapy device 214 of the NPWT system. In the event of detection of a leak, the NPWT system may generate a notification indicating the potential leak in the NPWT system and provide the notification to the mobile device 220, or the remote server 222.

[0118] The non-transitory computer-readable medium 902 may include a set of instructions executable by the processing resource 904 of the mobile device 220, remote server 222, or therapy device 214, as the case may be, to receive such a notification, and generate, on the mobile device, a prompt to a user to capture the audio signals emanating from the NPWT system. The non-transitory computer-readable medium 902 may include a set of instructions executable by the processing resource 904 to receive the audio signals captured by the user and trigger the above-mentioned analysis to determine whether the audio signals include components having frequency and intensity indicative of the leak in the NPWT system.

[0119] In an example implementation of the present subject matter, the instructions may cause identification of location of the leak in the NPWT system. Accordingly, the non-transitory computer- readable medium 902 may further include a set of instructions executable by the processing resource 904 to correlate a portion of the audio data where the frequencies corresponding to the predetermined range of frequencies are detected to a position of mobile device with respect to the NPWT system to identify the location of the leak. In an example, identification of the location of the leak may be based on video data that is time-synchronized with audio signals, as elaborated previously.

[0120] Thus, the techniques of the present subject matter provide for detection of leaks in the NPWT systems as well as identification of location of the leaks to without involving significant resources.EXAMPLES

[0121] The Applicant has performed experiments in different setups to test the capability of microphones of mobile devices to detect a leak in NPWT systems. Examples of these experiments are discussed herein.

[0122] In one experiment, a lab-made NPWT setup was used to test the performance of the microphone of the mobile device. To perform this experiment, a NPWT dressing of 3M™ Dermatac™ was used.

[0123] A leak was made manually by creating wrinkles at one edge of the NPWT dressing. Further, a pump was used to create a negative pressure within the NPWT dressing. A microphone of an Apple™ iPhone™ 11 was brought close to the leak by gradually moving the microphone. The microphone was kept at the location of the leak for a few seconds and was then gradually moved away from the leak. The audio corresponding to the sound emanating from the leak was captured and analysed in a MATLAB® platform to generate a frequency spectrum of the sound. It was observed that the frequency of the sound emanating from the leak was in the range of 5-20 kHz.

[0124] Series of experiments were also conducted with other types of dressings, for example, the 3M™ V.A.C® dressing and the 3M™ Prevena™ dressing. The frequency of the sound emanating from the leak was found to be in the range of 5-20 kHz for a variety of different types of dressing.

[0125] A series of experiment was further conducted on dressings placed over different types of wounds, such as flatbed and non-flatbed type of wounds. As the name indicates, the dressing in a flatbed type wound is placed on a flat surface, for example, the back of a patient, whereas in the non-flatbed type wound, the dressing is placed over a curved surface, for example, the ankle of the patient. The frequency of the sound emanating from the leak was found to be in the range of 5-20 kHz for the different types of wounds.

[0126] Similarly, a series of experiments were also conducted using microphones of several brands of mobile devices, such as smartphones and tablets. It was observed that the microphones were able to sense and capture sound emanating from the leak. The frequency of the sound emanating from the leak was found to be in the range of 5-20 kHz using the different types of mobile devices.

[0127] A series of experiments was also conducted to determine if the frequency of the sound emanating from the leak changes based on the leak rate of the leak. Accordingly, the pump was operatedto achieve different leak rates for the leak, for example, 0. IL, 0.3L, 0.4 L and 0.55 L. The corresponding leak rate was measured using an external flow sensor for confirmation of the leak rate. For each leak rate, frequency components were found to be in between 5-20 kHz when the microphone was close to the leak. It was further observed that even for leak rates as low as 0.1 L / min, the microphones were able to sense and capture sound emanating from the leak. Thus, it was observed that the frequency of the sound emanating from the leak was in the range of 5-20 KHz for the different leak rates.

[0128] In the various experiments that were conducted, several audio analysis tools were used for generating the frequency spectrum of the sound emanating from the NPWT setup to determine the frequency corresponding to the leak. In examples, audio analysis tools, when processing the input sound, i.e., the sound as captured by the microphone, comprising the background noise, sound emanating from the leak, and the sound of the pump, mapped the maximum intensity identified in the input sound to 0 db. The rest of the sound was scaled negative to the maximum value. Table 1 below shows the intensity of the background noise, sound emanating from the leak (leak sound) and the sound of the pump (pump sound) corresponding to different frequency components of the input sound, computed by such audio analysis tools.Table 1

[0129] Table 1 shows that the pump sound is dominant mostly in the range of frequency of 100 Hz - 1000 Hz region with a peak at 2500 Hz while the sound emanating from the leak is dominant mostly in the frequency range of 10 - 15 KHz. Accordingly, it was observed that the microphones were able to detect the leak even in the presence of sound generated owing to the running of the pump in the background.

[0130] In another series of experiments, the effect of distance from the location of the leak on the sensitivity of the microphones to detect a leak was analysed. A NPWT setup as described above was used to investigate how close the microphone is to be positioned with respect to the leak in order todetect the leak. A variety of microphones were used in these series of experiments. Typical intensity level of frequency components found in the sound emanating from the leak, as captured by a microphone, at different gradually increasing distances of the microphone from the location of the leak is presented in Table 2 below.Table 2

[0131] Table 2 shows that the intensity of frequency components in frequency range of 10 kHz -15 kHz gradually decreases with increased distance from the leak until a distance of 12 cm. However, even at a distance of 12 cm from the location of the leak, it was observed that the microphone was able to detect the sound emanating from the leak. Thus, based on the above results, it was observed that microphones that are a part of mobile devices are adequately sensitive to detect leaks in NPWT systems even at an increased distance.

[0132] Although implementations of techniques for detecting leaks in NPWT systems have been described in a language specific to structural features and / or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as example implementations for detecting leaks in the NPWT systems.

Claims

Claims:

1. A method for detecting leaks in a negative pressure wound therapy (NP WT) system, the method comprising: obtaining audio signals emanating from a NP WT system, wherein the audio signals are obtained using a microphone; determining, via a processor, whether the audio signals include components having frequencies corresponding to a predetermined range of frequencies; and assessing, based on the components having frequencies corresponding to the predetermined range of frequencies, whether a leak is present in the NPWT system, wherein the microphone is part of a mobile device, and wherein the audio signals are emanating from a NPWT dressing of the NPWT system, the NPWT dressing providing a sealed space for application of negative pressure.

2. The method as claimed in claim 1, further comprising: determining an amplitude associated with each of the components in the predetermined range of frequencies; and identifying, from amongst the components in the predetermined range of frequencies, the component with the highest amplitude, wherein the presence of the leak is assessed based on the component with the highest amplitude.

3. The method as claimed in claim 1, further comprising causing an alert indicative of presence of the leak to be generated on the mobile device.

4. The method as claimed in claim 1, wherein the predetermined range of frequencies is 15 kHz to 20 kHz.

5. The method as claimed in claim 1, wherein the audio signals emanating from the NPWT dressing is captured by moving the microphone of the mobile device along a perimeter of the NPWT dressing, the method further comprising: obtaining video data corresponding to the perimeter of the NPWT dressing captured simultaneously with the audio signals; and identifying, based on the video data, a location of the leak along the perimeter of the NPWT dressing.

6. The method as claimed in claim 5, further comprising: timestamping the audio signals captured by moving the microphone of the mobile device along the perimeter of the NPWT dressing; identifying timestamps associated with the components having the predetermined range of frequencies; and identifying, from the video data of the perimeter of the NPWT dressing captured simultaneously with the audio signals, a portion of the video data to correspond to the location of the leak based on the identified timestamps.

7. The method as claimed in claim 5, further comprising providing a visual indication of the location of the leak along the perimeter of the NPWT dressing on the mobile device.

8. The method as claimed in claim 1, further comprising: determining a potential leak in the NPWT system; and generating, on the mobile device, a prompt to a user to capture the audio signals emanating from the NPWT system.

9. A device for detecting leaks in a negative pressure wound therapy (NPWT) system, the device comprising: a processor; and a machine-readable storage medium comprising instructions executable by the processor to: analyze a frequency spectrum of sound emanating from the NPWT system; determine the frequency spectrum to comprise frequencies in a predetermined range of frequencies corresponding to leakage of fluid from a component of the NPWT system; and cause a notification of leakage of fluid from the component to be provided on a communication device associated with the NPWT system if the frequency spectrum comprises frequencies in the predetermined range of frequencies.

10. The device as claimed in claim 9, wherein the component is a NPWT dressing, a tubing, a connector or a trackpad of the NPWT system.

11. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: obtain data pertaining to respective range of frequencies corresponding to leakage of fluid from components of the NPWT system.

12. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: compute sound intensity of the portion of the frequency spectrum of the sound that comprises the frequencies in the predetermined range of frequencies; and determine the sound intensity to be above a threshold to cause the notification.

13. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: receive audio data captured by a microphone of a mobile device, the audio data corresponding to the sound emanating from the NPWT system.

14. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: receive, in real-time, audio data corresponding to the sound emanating from the NPWT system, wherein the sound is captured by a microphone of a mobile device by moving the microphone with respect to the NPWT system; andcorelate a portion of the audio data where the frequencies in the predetermined range of frequencies are detected to a real-time position of the microphone to identify a location of the leak.

15. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: receive audio signals captured by a microphone of a mobile device, the audio signals corresponding to the sound emanating from a NPWT dressing of the NPWT system, wherein the audio signals are captured by moving the microphone along a perimeter of the NPWT dressing; receive video data corresponding to the perimeter of the NPWT dressing, the video data being synchronized in time with the audio signals; and identify, based on the video data, a location of the leakage along the perimeter of the NPWT dressing.

16. The device as claimed in claim 9, wherein the instructions are executable by the processor to further: upon identification of leakage of fluid from the component of the NPWT system, store data relating to acoustic properties of the sound emanating from the component.

17. The device as claimed in claim 9, wherein the predetermined range of frequencies corresponding to leakage of fluid from the component of the NPWT system is 5 kHz to 20 kHz.

18. A non-transitory computer-readable medium comprising instructions, the instructions being executable by a processing resource to: analyze audio signals captured by a microphone of a mobile device to determine whether the audio signals include frequency components indicative of a leak in a negative pressure wound therapy (NPWT) system; determine a sound intensity associated with the frequency components indicative of the leak to be above a preset threshold; and cause a notification of the leakage to be provided on the mobile device on determining the sound intensity associated with the frequency components indicative of the leak to be above the preset threshold.

19. The non-transitory computer-readable medium as claimed in claim 18 further comprising computer-readable instructions executable to: receive the audio signals captured by the microphone of the mobile device, wherein the audio signals is captured by moving the mobile device with respect to the NPWT system; and corelate a portion of the audio signals where the frequency components indicative of the leak occur to a position of the mobile device with respect to the NPWT system to identify a location of the leak.

20. The non-transitory computer-readable medium as claimed in claim 18 further comprising computer-readable instructions executable to: receiving a notification of a potential leak in the NPWT system; andgenerate, on the mobile device, a prompt to a user to capture the audio signals emanating from the NPWT system.

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