# US 11,433,203 B2 · Methods and apparatus for treatment of respiratory disorders > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,433,203 B2 - Document ID: US11433203B2 - Status: Granted - Kind: B2 - Application number: 16/604,607 - Filed: 2018-05-11 - Published: 2021-04-22 - Granted: 2022-09-06 - Earliest claimed: 2017-05-12 - Assignees: ResMed Pty Ltd - Applicants: ResMed Pty Ltd - Inventors: Benjamin Matthew Austin; Etienne Veschambre - Web page: https://patentgrep.com/patent/US11433203B2 ## CPC - A61M 16/024: {including calculation means, e.g. using a processor} - A61M 16/0069: {the speed thereof being controlled by respiratory parameters, e.g. by inhalation} - A61M 16/105: {Filters (A61M16/047, A61M16/22 take precedence; water traps A61M16/08)} - A61M 16/16: Devices to humidify the respiration air {(A61M16/1045 takes precedence)} - A61M 2016/0021: {with a proportional output signal, e.g. from a thermistor} - A61M 2016/0027: {pressure meter} - A61M 2016/0036: {in the breathing tube and used in both inspiratory and expiratory phase} - A61M 2202/0208: Oxygen - A61M 2202/0225: Carbon oxides, e.g. Carbon dioxide - A61M 2205/15: Detection of leaks - A61M 2205/18: with alarm - A61M 2205/21: insensitive to tilting or inclination, e.g. spill-over prevention - A61M 2205/3553: remote, e.g. between patient's home and doctor's office - A61M 2205/3584: using modem, internet or Bluetooth® - A61M 2205/3592: using telemetric means, e.g. radio or optical transmission - A61M 2205/42: Reducing noise - A61M 2205/502: User interfaces, e.g. screens or keyboards - A61M 2205/52: with memories providing a history of measured variating parameters of apparatus or patient - 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)} ## Abstract Disclosed are methods, apparatus and systems for treating a respiratory disorder in a patient. The apparatus comprises a pressure generator configured to generate a flow of air so as to provide ventilatory support to the patient; a transducer configured to generate a flow signal representing a property of the flow of air; and a controller configured to analyse the flow signal to estimate the inspiratory volume and the expiratory volume of a breath of the patient and servo-control the degree of ventilatory support to adjust an estimated tidal volume toward a target tidal volume. A gain of the servo-control is dependent on a difference between the estimated inspiratory volume and the estimated expiratory volume. The method comprises operating an apparatus or system in a similar manner. ## Claims ### Claim 1 Apparatus for treating a respiratory disorder in a patient, the apparatus comprising: a pressure generator configured to generate a flow of air so as to provide ventilatory support to the patient; a transducer configured to generate a signal representing a property of the flow of air; and a controller configured to: analyse the signal to estimate an inspiratory volume and an expiratory volume of a breath of the patient; and servo-control a degree of the ventilatory support to adjust an estimated tidal volume toward a target tidal volume, wherein a gain of the servo-control is dependent on a difference between the estimated inspiratory volume and the estimated expiratory volume. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the gain decreases as the difference between the estimated inspiratory volume and the estimated expiratory volume increases. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the gain is dependent on the difference between the estimated inspiratory volume and the estimated expiratory volume relative to the estimated tidal volume. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the gain is dependent on the absolute magnitude of the difference between the estimated inspiratory volume and the estimated expiratory volume. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the degree of the ventilatory support is a pressure support of the ventilatory support. ### Claim 6 A method of operating a respiratory treatment apparatus configured to generate a flow of air so as to provide ventilatory support to a patient, the method comprising: measuring a property of the flow of air, using a transducer; analysing, in a controller, the measured property to estimate an inspiratory volume and an expiratory volume of a breath of the patient; calculating, in a controller, a gain dependent on a difference between the estimated inspiratory volume and the estimated expiratory volume; and servo-controlling, by a controller, a degree of the ventilatory support using the calculated gain to adjust an estimated tidal volume for the patient toward a target tidal volume. ### Claim 7 (depends on 6) The method of claim 6, wherein the calculating decreases the gain as the difference between the estimated inspiratory volume and the estimated expiratory volume increases. ### Claim 8 (depends on 6) The method of claim 6, wherein the gain is dependent on the difference between the estimated inspiratory volume and the estimated expiratory volume relative to the estimated tidal volume. ### Claim 9 (depends on 6) The method of claim 6, wherein the gain is dependent on the absolute magnitude of the difference between the estimated inspiratory volume and the estimated expiratory volume. ### Claim 10 (depends on 6) The method of claim 6, wherein the degree of the ventilatory support is a pressure support of the ventilatory support. ### Claim 11 A system for treating a respiratory disorder in a patient, comprising: means for generating a flow of air so as to provide ventilatory support to the patient; means for generating a signal representing a property of the flow of air; means for analysing the signal to estimate an inspiratory volume and an expiratory volume of a breath of the patient; and means for servo-controlling a degree of the ventilatory support to adjust an estimated tidal volume toward a target tidal volume, wherein a gain of the servo-control is dependent on a difference between the estimated inspiratory volume and the estimated expiratory volume. ### Claim 12 Apparatus for treating a respiratory disorder in a patient, the apparatus comprising: a blower configured to deliver a supply of air that provides ventilatory support to the patient; a transducer configured to generate a signal representing a property of the supply of air; and a controller configured to: analyse the signal to estimate an inspiratory volume and an expiratory volume of a breath of the patient; and adjust servo-control gain based on a difference between the estimated inspiratory volume and the estimated expiratory volume. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the controller adjusts the servo-control gain so that the gain decreases as the difference between the estimated inspiratory volume and the estimated expiratory volume increases. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein an adjustment in servo-control gain causes a reduction in a rate of adjustment of pressure support of the supply of air. ### Claim 15 (depends on 12) The apparatus of claim 12, wherein the controller is configured to adjust the servo-control gain when the difference is greater than or equal to 20%. ### Claim 16 (depends on 12) The apparatus of claim 12, wherein the controller is further configured to adjust the servo-control gain to a default value when the difference returns to a value that is less than 20%.