# US 10,307,517 B2 · Systems and methods for controlling operation of a reduced pressure therapy system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,517 B2 - Document ID: US10307517B2 - Status: Granted - Kind: B2 - Application number: 14/598,083 - Filed: 2015-01-15 - Published: 2015-08-06 - Granted: 2019-06-04 - Earliest claimed: 2010-09-20 - Assignees: Smith & Nephew, Inc. - Applicants: Smith & Nephew PLC - Inventors: Julie Allen; Ben Alan Askem; Sarah Jenny Collinson; Richard Thomas Hughey; Derek Nicolini - Web page: https://patentgrep.com/patent/US10307517B2 ## CPC - A61M 5/16831: {Monitoring, detecting, signalling or eliminating infusion flow anomalies (low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066)} - A61F 13/05: specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT] - A61M 1/73: {comprising sensors or indicators for physical values} - A61M 1/74: {Suction control (underwater drainage A61M1/61)} - A61M 1/743: {by changing the cross-section of the line, e.g. flow regulating valves (A61M1/7413 takes precedence)} - A61M 1/75: {Intermittent or pulsating suction (A61M1/63, A61M1/772 take precedence)} - A61M 1/80: {Suction pumps (A61M1/64, A61M1/71, A61M60/00 take precedence)} - A61M 1/90: {Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing} - A61M 1/96: {Suction control thereof} - A61M 5/48: having means for varying, regulating, indicating or limiting injection pressure (A61M5/142 takes precedence {; monitoring pressure in infusion systems A61M5/16854}) - A61M 39/22: Valves or arrangement of valves {(A61M39/02, A61M39/0247, A61M39/16 take precedence; regulating valves in infusion systems A61M5/16881; in devices worn by the patient for the reception of urine, faeces, catamenial or other discharge, or in colostomy devices A61F5/4405)} - A61F 2013/00174: {possibility of applying pressure} - A61M 1/732: {Visual indicating means for vacuum pressure} - A61M 1/966: {having a pressure sensor on or near the dressing} - A61M 1/985: {the dressing itself forming the collection container} - A61M 2205/15: Detection of leaks - A61M 2205/18: with alarm - A61M 2205/3344: Measuring or controlling pressure at the body treatment site - A61M 2205/42: Reducing noise - A61M 2205/8212: with means or measures taken for minimising energy consumption - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) ## Abstract Negative pressure wound therapy apparatuses and dressings, and systems and methods for operating such apparatuses for use with dressings are disclosed. In some embodiments, controlling the delivery of therapy can be based on monitoring and detecting various operating conditions. An apparatus can have a controller configured to monitor the duty cycle of a source of negative pressure and, based on the monitored duty cycle, determine whether a leak is present. The controller can be configured to provide an indication that a leak is present. For example, the controller can be configured to suspend and/or pause the delivery of therapy, and to restart the delivery of therapy due to a timeout, request from a user, etc. In addition, the controller can be configured to pause and/or restart the delivery of therapy upon a request from the user, such as in response to the user operating a switch. ## Claims ### Claim 1 An apparatus for applying negative pressure to a wound, the apparatus comprising: a negative pressure pump disposed in a housing, the negative pressure pump being configured to provide negative pressure to a dressing placed over the wound to create a seal over the wound; and a controller programmed to: detect a condition indicative of a leak in the seal when the negative pressure pump is providing negative pressure under the dressing, pause operation of the negative pressure pump in response to detecting the condition, and restart operation of the negative pressure pump in response to expiration of a first period of time during which operation of the negative pressure pump is paused in response to detecting the condition. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the controller is programmed to detect the condition based at least on an indication of a level of activity of the negative pressure pump. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the controller is programmed to detect the condition based at least on a duty cycle of the negative pressure pump. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the controller is programmed to detect the condition in response to determining that the duty cycle satisfies a duty cycle threshold. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the controller is programmed to detect the condition based at least on a pressure under the dressing. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the controller is programmed to detect the condition in response to determining that the pressure has not reached a pressure level after expiration of a second period of time during which the negative pressure pump is providing negative pressure under the dressing. ### Claim 7 (depends on 5) The apparatus of claim 5, further comprising a sensor configured to measure the pressure and to communicate the pressure to the controller. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the controller is programmed to detect the condition based at least on an aspirate from the wound. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the controller is programmed to detect the condition in response to determining that a flow rate of a fluid of the aspirate satisfies a flow rate threshold. ### Claim 10 (depends on 1) The apparatus of claim 1, further comprising the dressing. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the first period of time is between 1 second and 1 minute. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the first period of time is set by a user. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the controller is programmed to repeatedly both (1) pause operation of the negative pressure pump in response to detecting the condition and (2) restart operation of the negative pressure pump in response to expiration of the first period of time. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein controller is programmed to increase the first period of time in response to restarting operation of the negative pressure pump at least one time. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein until a maximum number of retry attempts is reached, the controller is programmed to repeatedly both (1) pause operation of the negative pressure pump in response to detecting the condition and (2) restart operation of the negative pressure pump in response to expiration of the first period of time. ### Claim 16 A method of operating a negative pressure pump configured to provide negative pressure under a dressing, the dressing configured to be placed over a wound and to create a seal over the wound, the method comprising: detecting a condition indicative of a leak in the seal when the negative pressure pump is providing negative pressure under the dressing; pausing operation of the negative pressure pump in response to detecting the condition; and restarting operation of the negative pressure pump in response to expiration of a first period of time during which operation of the negative pressure pump is paused in response to detecting the condition, wherein the method is performed by a controller. ### Claim 17 (depends on 16) The method of claim 16, wherein said detecting comprises detecting the condition based at least on an indication of a level of activity of the negative pressure pump. ### Claim 18 (depends on 16) The method of claim 16, wherein said detecting comprises detecting the condition based at least on a duty cycle of the negative pressure pump. ### Claim 19 (depends on 16) The method of claim 16, wherein said detecting comprises detecting the condition in response to determining that a pressure under the dressing has not reached a pressure level after expiration of a second period of time during which the negative pressure pump is providing negative pressure under the dressing, the second period of time being at least 5 seconds. ### Claim 20 (depends on 16) The method of claim 16, further comprising repeatedly both (1) pausing operation of the negative pressure pump in response to detecting the condition and (2) restarting operation of the negative pressure pump in response to expiration of the first period of time. ### Claim 21 (depends on 20) The method of claim 20, further comprising in response to restarting operation of the negative pressure pump at least one time, increasing the first period of time.