# US 11,077,267 B2 · Pressure adjustment method for CPAP machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,077,267 B2 - Document ID: US11077267B2 - Status: Granted - Kind: B2 - Application number: 15/868,713 - Filed: 2018-01-11 - Published: 2018-05-17 - Granted: 2021-08-03 - Earliest claimed: 2010-12-21 - Assignees: Fisher & Paykel Healthcare Limited - Applicants: Fisher & Paykel Healthcare Limited - Inventors: David Robin Whiting; Andrew Gordon Gerred; Fiona Elizabeth Cresswell - Web page: https://patentgrep.com/patent/US11077267B2 ## CPC - A61M 16/0069: {the speed thereof being controlled by respiratory parameters, e.g. by inhalation} - A61B 5/4818: {Sleep apnoea} - A61B 5/4836: {Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence)} - A61M 16/0003: {Accessories therefor, e.g. sensors, vibrators, negative pressure} - A61M 16/024: {including calculation means, e.g. using a processor} - A61M 16/16: Devices to humidify the respiration air {(A61M16/1045 takes precedence)} - A61M 2016/0027: {pressure meter} - A61M 2016/003: {with a flowmeter} - A61M 2016/0036: {in the breathing tube and used in both inspiratory and expiratory phase} - A61M 2205/3331: Pressure; Flow - 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)} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A positive airway pressure apparatus is automatically adjusting. Pressure increases in response to apnea events when the apparatus is in one or more responsive states. Pressure does not increase in response to apnea events when the apparatus is in a non-responsive state. The apparatus switches between responsive and nonresponsive states depending upon any of a number of different criteria that help differentiate between open airway apnea events and closed airway apnea events. ## Claims ### Claim 1 A method for controlling an automatically adjusting PAP apparatus, the method comprising: operating in a responsive state wherein the PAP apparatus is configured to respond to sleep disordered breathing events by increasing an output pressure by a preset amount; in response to the detected sleep disordered breathing events, increasing a counter; entering a pause state when the counter exceeds a threshold; in response to sensing a patient arousal or a predetermined period of time without sleep disordered breathing events, exiting the pause state and decreasing the output pressure; and in response to detecting a first sleep disordered breathing event after the decrease in the output pressure, increasing the output pressure by a function of the decrease in the output pressure. ### Claim 2 (depends on 1) The method of claim 1, wherein the first sleep disordered breathing event after the decrease in the output pressure is an apnea. ### Claim 3 (depends on 1) The method of claim 1, wherein the first sleep disordered breathing event after the decrease in the output pressure is a combination of events. ### Claim 4 (depends on 3) The method of claim 3, wherein the combination of events is a combination of apneas and non-flow limited hypopneas. ### Claim 5 (depends on 3) The method of claim 3, wherein the combination of events is an apnea preceded by an apnea or non-flow limited hypopnea within a predetermined period of time. ### Claim 6 (depends on 1) The method of claim 1, wherein the function is one half of the decrease in the output pressure. ### Claim 7 (depends on 1) The method of claim 1, wherein if the decrease in output pressure is less than 3 cm H2O, the output pressure is increased by a predetermined amount. ### Claim 8 (depends on 1) The method of claim 1, wherein if the decrease in output pressure is greater than 3 cm H2O, the output pressure is increased by half of the decrease in output pressure. ### Claim 9 (depends on 1) The method of claim 1, wherein the output pressure is decreased faster in response to the patient arousal than in response to the predetermined period of without sleep disordered breathing events. ### Claim 10 (depends on 1) The method of claim 1, further comprising resetting the counter if the output pressure reaches a minimum pressure as a result of the pressure decrease. ### Claim 11 (depends on 1) The method of claim 1, further comprising, in response to a sleep disordered breathing event having occurred during the decrease in the output pressure, stopping the decrease in the output pressure. ### Claim 12 (depends on 1) The method of claim 1, wherein, when in the pause state, an increase in the output pressure is paused in response to detecting an apnea. ### Claim 13 (depends on 1) The method of claim 1, wherein, when in the pause state, the output pressure is increased in response to detecting flow-limited breaths or a non-flow limited hypopnea. ### Claim 14 An apparatus comprising: a gases flow source configured to supply gases to a patient in use; a sensor configured to sense pressure or flow or both, supplied by the flow source or supplied to the patient; and a controller configured to receive output from the sensor, determine sleep disordered breathing events based on the output from the sensor, and control an output pressure of the flow source according to a pressure adjusting algorithm wherein the controller is configured to: operate in a responsive state wherein the controller is configured to respond to sleep disordered breathing events by increasing an output pressure by a preset amount in response to the detected sleep disordered breathing events, increase a counter; enter a pause state when the counter exceeds a threshold; in response to sensing a patient arousal or a predetermined period of time without sleep disordered breathing events, exit the pause state and decrease the output pressure; and in response to detecting a first sleep disordered breathing event after the decrease in the output pressure, increase the output pressure by a function of the decrease in the output pressure. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the first sleep disordered breathing event after the decrease in the output pressure is an apnea preceded by an apnea or non-flow limited hypopnea within a predetermined period of time. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the function is one half of the decrease in the output pressure. ### Claim 17 (depends on 14) The apparatus of claim 14, wherein if the decrease in the output pressure is less than a pressure threshold, the controller is configured to increase the output pressure by a predetermined amount, and if the decrease in the output pressure is greater than the pressure threshold, the controller is configured to increase the output pressure by half of the decrease in the output pressure. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the predetermined amount is 1 cm H2O. ### Claim 19 (depends on 14) The apparatus of claim 14, wherein the controller is configured to pause an increase in the output pressure, when in the pause state, in response to detecting an apnea. ### Claim 20 (depends on 14) The apparatus of claim 14, wherein the controller is configured to increase the output pressure, when in the pause state, in response to detecting flow-limited breaths or a non-flow limited hypopnea.