# US 2013/0152934 A1 · Adaptive cycling for respiratory treatment apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0152934 A1 - Document ID: US20130152934A1 - Status: Published application - Kind: A1 - Application number: 13/819,037 - Filed: 2011-08-25 - Published: 2013-06-20 - Earliest claimed: 2010-08-27 - Assignees: ResMed Limited - Inventors: Qestra Camille Mulqueeny; Didier Tassaux - Web page: https://patentgrep.com/patent/US20130152934A1 ## CPC - A61M 16/0069: {the speed thereof being controlled by respiratory parameters, e.g. by inhalation} - A61M 16/0066: {Blowers or centrifugal pumps} - A61M 16/026: {specially adapted for predicting, e.g. for determining an information representative of a flow limitation during a ventilation cycle by using a root square technique or a regression analysis} - A61M 2016/0027: {pressure meter} - A61M 2016/0039: {in the inspiratory circuit} - A61M 2205/50: with microprocessors or computers - A61M 2230/46: Resistance or compliance of the lungs - A61M 2230/60: Muscle strain, i.e. measured on the user - 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 A controller or processor (s) implements detection of respiratory related conditions that may serve as control logic to synchronize pressure treatment delivery with a patient's respiratory cycle. Based on data derived from sensor signals associated with the respiratory treatment, a monitoring device, detector or respiratory treatment apparatus may evaluate flow measures from a flow sensor and distinguish flow attributable to the respiratory treatment apparatus and flow attributable to patient respiratory muscles. The determination may serve as a basis of synchronization criteria that controls pressure levels from a pressure treatment apparatus, such as by evaluating the determined patient generated flow or a relationship between total flow and apparatus flow. In some embodiments, data for the cycling conditions is determined in preliminary treatment cycles during which synchronized pressure changes are controlled according to other cycling criteria. The new cycling conditions are then automatically initiated for control of synchronization in subsequent cycles. ## Claims ### Claim 1 An automated processing method for adapting cycling of a respiratory treatment apparatus that controls a delivery of a synchronized respiratory treatment, the method comprising: controlling generation of inspiratory pressure and expiratory pressure over a first plurality of cycles with a processor, wherein the setting of the expiratory pressure is based on a first cycling criteria; and controlling generation of inspiratory pressure and expiratory pressure over a second plurality of cycles subsequent to the first plurality of cycles with the processor, wherein the setting of the expiratory pressure is based on a second cycling criteria, the second cycling criteria being different from the first cycling criteria and being initiated for operation subsequent to the first plurality of cycles. ### Claim 2 (depends on 1) The method of claim 1 wherein the second cycling criteria comprises a function of a first inspiratory flow measure and a second inspiratory flow measure, the second inspiratory flow measure attributable to the respiratory treatment apparatus. ### Claim 3 (depends on 2) The method of claim 2 wherein the first cycling criteria comprises comparing an instantaneous flow measure to a threshold proportion of a peak flow. ### Claim 4 (depends on 1) The method of claim 1 wherein the control of the first plurality of cycles comprises a learning period that is configured for determining and storing values for control of treatment in a plurality of subsequent treatment sessions. ### Claim 5 (depends on 1) The method of claim 1 wherein the control of the first plurality of cycles comprises a learning period that is initiated in each treatment session. ### Claim 6 (depends on 1) The method of claim 1 further comprising determining values of the second cycling criteria during the control of the first plurality of cycles. ### Claim 7 (depends on 6) The method of claim 6 wherein the determined values of the second cycling criteria comprise an inspiratory time constant. ### Claim 8 (depends on 7) The method of claim 7 wherein the inspiratory time constant is a function of a determined slope of an expiratory portion of a measured flow from the first plurality of cycles. ### Claim 9 (depends on 8) The method of claim 8 wherein the inspiratory time constant is a mean of a plurality of determined slopes of expiratory portions of a measured flow from the first plurality of cycles. ### Claim 10 (depends on 7) The method of claim 7 wherein the inspiratory time constant is a measured time for a proportion of a tidal volume to be delivered to the patient's respiratory system in a cycle of the first plurality of cycles. ### Claim 11 (depends on 10) The method of claim 10 wherein the inspiratory time constant is a mean of measured times for a proportion of a tidal volume to be delivered to the patient's respiratory system in the first plurality of cycles. ### Claim 12 (depends on 7) The method of claim 7 wherein a determination of the inspiratory time constant comprises a multiple linear regression process to fit pressure, flow and volume data for determining a measure of resistance and compliance. ### Claim 13 (depends on 2) The method of claim 2 wherein the function of the first inspiratory flow measure and the second inspiratory flow measure comprises an equality of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 14 (depends on 2) The method of claim 2 wherein the function of the first inspiratory flow measure and the second inspiratory flow measure comprises a calculated difference of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 15 (depends on 2) The method of claim 2 wherein the second inspiratory flow measure is a function of a determined flow peak, a calculated respiratory resistance and a pressure treatment setting. ### Claim 16 A respiratory treatment apparatus for cycling synchronized respiratory pressure treatment, the apparatus comprising: a patient interface to direct a breathable gas; a flow generator coupled with the patient interface to generate the breathable gas in inspiratory and expiratory pressure cycles through the patient interface; a flow sensor to provide a signal indicative of flow through the patient interface; a processor, coupled with the flow generator and the flow sensor, the processor configured to control: generation of inspiratory pressure and expiratory pressure over a first plurality of cycles, wherein the setting of the expiratory pressure is based on a first cycling criteria; and generation of inspiratory pressure and expiratory pressure over a second plurality of cycles subsequent to the first plurality of cycles, wherein the setting of the expiratory pressure is based on a second cycling criteria, the second cycling criteria being different from the first cycling criteria and being initiated for operation subsequent to the first plurality of cycles. ### Claim 17 (depends on 16) The apparatus of claim 16 wherein the second cycling criteria comprises a function of a first inspiratory flow measure from the flow sensor and a second inspiratory flow measure attributable to the respiratory treatment apparatus. ### Claim 18 (depends on 17) The apparatus of claim 17 wherein the first cycling criteria comprises comparing an instantaneous flow measure to a threshold proportion of a peak flow. ### Claim 19 (depends on 16) The apparatus of claim 16 wherein the control of the first plurality of cycles comprises a learning period that is configured for determining and storing values for control of treatment in a plurality of subsequent treatment sessions. ### Claim 20 (depends on 16) The apparatus of claim 16 wherein the control of the first plurality of cycles comprises a learning period that is initiated in each treatment session. ### Claim 21 (depends on 16) The apparatus of claim 16 further comprising determining values of the second cycling criteria during the control of the first plurality of cycles. ### Claim 22 (depends on 21) The apparatus of claim 21 wherein the determined values of the second cycling criteria comprise an inspiratory time constant. ### Claim 23 (depends on 22) The apparatus of claim 22 wherein the inspiratory time constant is a function of a determined slope of an expiratory portion of a measured flow from the first plurality of cycles. ### Claim 24 (depends on 23) The apparatus of claim 23 wherein the inspiratory time constant is a mean of a plurality of determined slopes of expiratory portions of a measured flow from the first plurality of cycles. ### Claim 25 (depends on 22) The apparatus of claim 22 wherein the inspiratory time constant is a measured time for a proportion of a tidal volume to be delivered to the patient's respiratory system in a cycle of the first plurality of cycles. ### Claim 26 (depends on 25) The apparatus of claim 25 wherein the inspiratory time constant is a mean of measured times for a proportion of a tidal volume to be delivered to the patient's respiratory system in the first plurality of cycles. ### Claim 27 (depends on 22) The apparatus of claim 22 wherein the inspiratory time constant is calculated as a function of resistance and compliance values determined by a multiple linear regression process with pressure, flow and volume data. ### Claim 28 (depends on 17) The apparatus of claim 17 wherein the function of the first inspiratory flow measure and the second inspiratory flow measure comprises an equality of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 29 (depends on 17) The apparatus of claim 17 wherein the function of the first inspiratory flow measure and the second inspiratory flow measure comprises a calculated difference of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 30 (depends on 17) The apparatus of claim 17 wherein the second inspiratory flow measure is a function of a determined flow peak, a calculated respiratory resistance and a pressure treatment setting. ### Claim 31 An automated processing method for cycling a respiratory treatment apparatus that controls a delivery of a synchronized respiratory treatment, the method comprising: determining a first flow measure with a flow sensor; determining a second flow measure attributable to the respiratory treatment apparatus; and evaluating, with a processor, a cycling criteria as a function of the first flow measure and the second flow measure. ### Claim 32 (depends on 31) The automated method of claim 31 wherein the evaluation of the cycling criteria is a further function of a tolerance coefficient. ### Claim 33 (depends on 31) The method of claim 31 wherein the determining of the second flow measure attributable to the respiratory treatment apparatus comprises calculating the second flow measure as function of an inspiratory resistance value and an inspiratory time constant value. ### Claim 34 (depends on 33) The method of claim 33 further comprising calculating the inspiratory resistance value. ### Claim 35 (depends on 34) The method of claim 34 wherein the calculating of the inspiratory resistance value comprises a function of airway pressure and flow. ### Claim 36 (depends on 35) The method of claim 35 wherein the airway pressure comprises a difference of a positive end expiratory pressure and an airway pressure following a peak in a measure of respiratory flow. ### Claim 37 (depends on 33) The method of claim 33 wherein the calculating the second flow measure is a further function of a ventilator time constant. ### Claim 38 (depends on 37) The method of claim 37 wherein the calculating the second flow measure is a further function of a pressure support setting. ### Claim 39 (depends on 31) The method of claim 31 wherein the evaluation of the cycling criteria comprises assessing an equality of the first flow measure and the second flow measure ### Claim 40 (depends on 31) The method of claim 31 wherein the evaluation of the cycling criteria comprises calculating a difference of the first flow measure and the second flow measure. ### Claim 41 (depends on 40) The method of claim 40 wherein the evaluation of the cycling criteria further comprises comparing the difference to a threshold. ### Claim 42 (depends on 41) The method of claim 41 wherein the threshold is zero. ### Claim 43 (depends on 31) The method of claim 31 further comprising setting an expiratory pressure based on the evaluation of the cycling criteria. ### Claim 44 (depends on 31) The method of claim 31 wherein the expiratory pressure comprises a positive end expiratory pressure. ### Claim 45 (depends on 31) The method of claim 31 further comprising: controlling generation of inspiratory pressure and expiratory pressure over a first number of cycles, wherein the setting of the expiratory pressure is based on a first cycling criteria; during the first number of cycles, determining an inspiratory time constant as a function of flow measures; setting a second cycling criteria as a function of the determined inspiratory time constant, the second cycling criteria for controlling generation of expiratory pressure over a second number of cycles subsequent to the first number of cycles. ### Claim 46 (depends on 45) The method of claim 45 wherein the determined inspiratory time constant comprises a slope of an expiratory part of a curve represented by the flow measures. ### Claim 47 (depends on 46) The method of claim 46 wherein the determined inspiratory time constant comprises a mean slope. ### Claim 48 (depends on 45) The method of claim 45 wherein the first cycling criteria comprises a threshold proportion of flow and the second cycling criteria comprises the cycling criteria of the function of the first flow measure and the second flow measure attributable to the respiratory treatment apparatus. ### Claim 49 A respiratory treatment apparatus for cycling synchronized respiratory pressure treatment, the apparatus comprising: a patient interface to direct a breathable gas; a flow generator coupled with the patient interface to generate the breathable gas in inspiratory and expiratory pressure cycles through the patient interface; a flow sensor to provide a signal indicative of patient flow through the patient interface; a processor, coupled with the flow generator and the flow sensor, the processor configured to control: a determination of a first flow measure from the flow sensor; a determination of a second flow measure attributable to the respiratory treatment apparatus; and an evaluation of a cycling criteria as a function of the first flow measure and the second flow measure. ### Claim 50 (depends on 49) The apparatus of claim 49 wherein the evaluation of the cycling criteria is a further function of a tolerance coefficient. ### Claim 51 (depends on 31) The apparatus of claim 31 wherein the determination of the second flow measure attributable to the respiratory treatment apparatus comprises calculating the second flow measure as function of an inspiratory resistance value and an inspiratory time constant value. ### Claim 52 (depends on 51) The apparatus of claim 51 wherein the processor is further configured to calculate the inspiratory resistance value. ### Claim 53 (depends on 52) The apparatus of claim 52 wherein the calculation of the inspiratory resistance value comprises a function of airway pressure and flow. ### Claim 54 (depends on 53) The apparatus of claim 53 wherein the airway pressure comprises a difference of a positive end expiratory pressure and an airway pressure following a peak in a measure of respiratory flow. ### Claim 55 (depends on 54) The apparatus of claim 54 wherein the calculation of the second flow measure is a further function of a ventilator time constant. ### Claim 56 (depends on 55) The method of claim 55 wherein the calculation of the second flow measure is a further function of a pressure support setting. ### Claim 57 (depends on 49) The apparatus of claim 49 wherein the evaluation of the cycling criteria comprises an assessment of an equality of the first flow measure and the second flow measure. ### Claim 58 (depends on 49) The apparatus of claim 49 wherein the evaluation of the cycling criteria comprises a calculation of a difference of the first flow measure and the second flow measure. ### Claim 59 (depends on 58) The apparatus of claim 58 wherein the evaluation of the cycling criteria further comprises comparing the difference to a threshold. ### Claim 60 (depends on 59) The apparatus of claim 59 wherein the threshold is zero. ### Claim 61 (depends on 49) The apparatus of claim 49 wherein the processor is configured to set an expiratory pressure based on the evaluation of the cycling criteria. ### Claim 62 (depends on 49) The apparatus of claim 49 wherein the expiratory pressure comprises a positive end expiratory pressure. ### Claim 63 (depends on 49) The apparatus of claim 49 wherein the processor is further configured to: control generation of inspiratory pressure and expiratory pressure over a first number of cycles, wherein the setting of the expiratory pressure is based on a first cycling criteria; during the first number of cycles, control a determination of an inspiratory time constant as a function of flow measures; set a second cycling criteria as a function of the determined inspiratory time constant, the second cycling criteria to control generation of expiratory pressure over a second number of cycles subsequent to the first number of cycles. ### Claim 64 (depends on 63) The apparatus of claim 63 wherein the determined inspiratory time constant comprises a slope of an expiratory part of a curve represented by the flow measures. ### Claim 65 (depends on 64) The apparatus of claim 64 wherein the determined inspiratory time constant comprises a mean slope. ### Claim 66 (depends on 63) The apparatus of claim 63 wherein the first cycling criteria comprises a threshold proportion of flow and the second cycling criteria comprises the cycling criteria of the function of the first flow measure and the second flow measure attributable to the respiratory treatment apparatus. ### Claim 67 An automated processing method to determine a signal indicative of patient respiration for synchronization of a respiratory treatment apparatus, the method comprising: determining a first inspiratory flow measure with a flow sensor; determining a second inspiratory flow measure; and determining, with a processor, a patient respiration measure as a function of the first inspiratory flow measure, the second inspiratory flow measure and an estimate of resistance and compliance derived from an expiratory portion of a flow measure of the flow sensor, the patient respiratory measure representing patient respiratory muscles effort; and determining a timing for switching a pressure treatment based on the respiration measure. ### Claim 68 (depends on 67) The method of claim 67 wherein the second inspiratory flow measure is a measure of flow attributable to the respiratory treatment apparatus. ### Claim 69 (depends on 68) The method of claim 68 further comprising calculating a resistance value for the estimate. ### Claim 70 (depends on 69) The method of claim 69 wherein the calculating of the resistance value comprises a function of airway pressure and flow. ### Claim 71 (depends on 70) The method of claim 70 further comprising calculating a compliance value for the estimate. ### Claim 72 (depends on 71) The method of claim 71 wherein the calculating the resistance and compliance values comprises multiple linear regression processing of an expiratory breath data portion, the expiratory breath data portion beginning with expiration and ending before a next inspiration. ### Claim 73 (depends on 72) The method of claim 72 wherein the ending before the next inspiration comprises a percentage of the tidal volume expired. ### Claim 74 (depends on 68) The method of claim 68 further comprising calculating a difference of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 75 A monitoring apparatus to determine a signal indicative of patient respiration for synchronization of a respiratory treatment, the apparatus comprising: a controller having at least one processor to access data representing a measured flow of breathable gas from a flow sensor, the controller being further configured to: determine a first inspiratory flow measure with the data; determine a second inspiratory flow measure; and determine a patient respiration signal as a function of the first inspiratory flow measure, the second inspiratory flow measure and an estimate of resistance and compliance derived from an expiratory portion of a flow measure of the flow sensor, the patient respiratory signal representing effort attributable to patient respiratory muscles; and determine a timing for switching a pressure treatment based on the respiration measure. ### Claim 76 (depends on 75) The apparatus of claim 75 wherein the controller is further configured to calculate a resistance value for the estimate. ### Claim 77 (depends on 76) The apparatus of claim 76 wherein the calculation of the resistance value comprises a function of airway pressure and flow. ### Claim 78 (depends on 77) The apparatus of claim 77 wherein the controller is further configured to calculate a compliance value for the estimate. ### Claim 79 (depends on 77) The apparatus of claim 77 wherein the calculation of the resistance and compliance values of the estimate is performed by the controller in multiple linear regression processing of an expiratory breath data portion, the expiratory breath data portion beginning with expiration and ending before a next inspiration. ### Claim 80 (depends on 75) The apparatus of claim 75 wherein the ending before the next inspiration comprises a percentage of the tidal volume expired. ### Claim 81 (depends on 75) The apparatus of claim 75 wherein the controller is further configured to calculate a difference of the first inspiratory flow measure and the second inspiratory flow measure. ### Claim 82 An automated processing method for cycling a respiratory treatment apparatus that controls a delivery of a synchronized respiratory treatment, the method comprising: determining a flow measure with a flow sensor; determining a pressure measure with a pressure sensor; determining, with a processor, an estimate of muscle effort as a function of the flow measure and pressure measure; and deriving, with the processor, a cycling control signal as a function of the estimate of muscle effort. ### Claim 83 (depends on 82) The method of claim 82 wherein the determining the estimate is a further function of an estimate of respiratory resistance and compliance. ### Claim 84 (depends on 83) The method of claim 83 wherein the estimate of respiratory resistance and compliance is determined as a function of a portion of patient expiration. ### Claim 85 (depends on 84) The method of claim 84 wherein the estimate is derived from pressure, flow and volume measures taken during the portion of patient expiration. ### Claim 86 (depends on 85) The method of claim 85 wherein the derived estimate is produced by multiple linear regression processing of the pressure, flow and volume measures taken during the portion of patient expiration beginning at patient expiration and ending when approximately ninety percent of a tidal volume has been expired. ### Claim 87 (depends on 82) The method of claim 82 further comprising determining a peak value of the control signal. ### Claim 88 (depends on 87) The method of claim 87 further comprising cycling the respiratory treatment apparatus as a function of a proportion of the peak value and the control signal. ### Claim 89 (depends on 88) The method of claim 88 wherein deriving the control signal comprises setting the control signal to equal the estimate of muscle effort if the estimate of muscle effort is increasing. ### Claim 90 (depends on 89) The method of claim 89 wherein deriving the control signal comprises setting the control signal to zero upon detection of inspiration or if the estimate of muscle effort is decreasing. ### Claim 91 A respiratory treatment apparatus for cycling synchronized respiratory pressure treatment, the apparatus comprising: a patient interface to direct a breathable gas; a flow generator coupled with the patient interface to generate the breathable gas in inspiratory and expiratory pressure cycles through the patient interface; a flow sensor to provide a signal indicative of patient flow through the patient interface; a pressure sensor to provide a signal indicative of pressure at the patient interface; a processor, coupled with the flow generator, the pressure sensor and the flow sensor, the processor configured to control: a determination of a flow measure with the flow sensor; a determination of a pressure measure with the pressure sensor; a determination of an estimate of muscle effort as a function of the flow measure and pressure measure; and a derivation of a cycling control signal as a function of the estimate of muscle effort. ### Claim 92 (depends on 91) The apparatus of claim 91 wherein the determination of the estimate is a further function of an estimate of respiratory resistance and compliance. ### Claim 93 (depends on 92) The apparatus of claim 92 wherein the estimate of respiratory resistance and compliance is determined as a function of a portion of patient expiration. ### Claim 94 (depends on 93) The apparatus of claim 93 wherein the estimate is derived from pressure, flow and volume measures taken during the portion of patient expiration. ### Claim 95 (depends on 94) The apparatus of claim 94 wherein the derived estimate is produced by multiple linear regression processing of the pressure, flow and volume measures taken during the portion of patient expiration beginning at patient expiration and ending when approximately ninety percent of a tidal volume has been expired. ### Claim 96 (depends on 91) The apparatus of claim 91 wherein the processor further controls a determination of a peak value of the control signal. ### Claim 97 (depends on 96) The apparatus of claim 96 wherein the processor further controls cycling the respiratory treatment apparatus as a function of a proportion of the peak value and the control signal. ### Claim 98 (depends on 97) The apparatus of claim 97 wherein the derivation of the control signal comprises setting the control signal to equal the estimate of muscle effort if the estimate of muscle effort is increasing. ### Claim 99 (depends on 98) The apparatus of claim 98 wherein the derivation of the control signal further comprises setting the control signal to zero upon detection of inspiration or if the estimate of muscle effort is decreasing. ### Claim 100 A respiratory treatment apparatus for switching synchronized respiratory pressure treatment, the apparatus comprising: a patient interface to direct a breathable gas; a flow generator coupled with the patient interface to generate the breathable gas in inspiratory and expiratory pressure cycles through the patient interface; an electro-optical sensor for non-invasively measuring diaphragmatic muscle activity; and a processor, coupled with the flow generator and the sensor, the processor configured to control: a determination of muscle effort signal with the sensor; and a derivation of a switching control signal as a function of the muscle effort signal. ### Claim 101 (depends on 100) The apparatus of claim 100 wherein the processor further controls a determination of a peak value of the control signal. ### Claim 102 (depends on 100) The apparatus of claim 100 wherein the processor further controls cycling the respiratory treatment apparatus as a function of a proportion of the peak value and the control signal. ### Claim 103 (depends on 102) The apparatus of claim 102 wherein the derivation of the control signal comprises setting the control signal to equal the muscle effort signal if the muscle effort signal is increasing. ### Claim 104 (depends on 103) The apparatus of claim 103 wherein the derivation of the control signal further comprises setting the control signal to zero upon detection of inspiration or if the muscle effort signal is decreasing. ### Claim 105 (depends on 100) The apparatus of claim 100 wherein the processor further controls cycling a pressure treatment controlled by the apparatus is a function of the switching control signal. ### Claim 106 (depends on 100) The apparatus of claim 100 wherein the processor further controls triggering a pressure treatment controlled by the apparatus is a function of the switching control signal.