# US 11,896,767 B2 · Model-driven system integration in medical ventilators > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,896,767 B2 - Document ID: US11896767B2 - Status: Granted - Kind: B2 - Application number: 17/178,349 - Filed: 2021-02-18 - Published: 2021-09-23 - Granted: 2024-02-13 - Earliest claimed: 2020-03-20 - Assignees: Covidien LP - Applicants: Covidien LP - Inventors: Nancy F. Dong; Gabriel Sanchez; Kun Li - Web page: https://patentgrep.com/patent/US11896767B2 ## CPC - A61M 16/00: Devices for influencing the respiratory system of patients by gas treatment, e.g. ventilators (iron lungs A61H31/02); Tracheal tubes - A61M 16/08: Bellows; Connecting tubes {(having means for taking samples G01N1/22); Water traps; Patient circuits} - A61M 16/0003: {Accessories therefor, e.g. sensors, vibrators, negative pressure} - A61M 16/024: {including calculation means, e.g. using a processor} - A61M 16/20: Valves specially adapted to medical respiratory devices - A61M 16/205: {used for exhalation control} - G16H 20/40: relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture - G16H 40/40: for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades - G16H 40/63: for local operation - A61M 16/202: {electrically actuated} - A61M 16/208: {Non-controlled one-way valves, e.g. exhalation, check, pop-off non-rebreathing valves} - A61M 2016/0027: {pressure meter} - A61M 2016/003: {with a flowmeter} - A61M 2016/0039: {in the inspiratory circuit} - A61M 2016/0042: {in the expiratory circuit} - A61M 2205/18: with alarm - A61M 2205/33: Controlling, regulating or measuring - A61M 2205/3334: Measuring or controlling the flow rate - A61M 2205/3368: Temperature - A61M 2205/3569: sublocal, e.g. between console and disposable - A61M 2205/3584: using modem, internet or Bluetooth® - A61M 2205/3592: using telemetric means, e.g. radio or optical transmission - A61M 2205/50: with microprocessors or computers - A61M 2205/502: User interfaces, e.g. screens or keyboards - A61M 2205/505: Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches - A61M 2205/70: with testing or calibration facilities - 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)} - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract Systems and methods for model-driven system integration on a ventilator comprise a modeled exhalation flow. Ventilator flow sensors contain components that are easily damaged or impacted and have high rates of failure. Knowledge failure frequency and type may help determine when to replace, clean, or calibrate a flow sensor. A modeled exhalation flow may be trained for a ventilator. Additionally, the modeled exhalation flow may be compared to a flow sensor flow to determine a specific failure. Additionally or alternatively, the modeled exhalation flow may supplement, weight, or replace a faulty flow sensor measurement. These systems and methods may assist in identifying an inaccurate flow sensor measurement and/or providing a more accurate modeled flow estimate, thus increasing accuracy in patient-ventilator interactions. ## Claims ### Claim 1 A method for operating a ventilator without an operational exhalation flow sensor, comprising: measuring an exhalation pressure of a breathing circuit at a pressure sensor associated with an exhalation valve; measuring an electrical current provided to the exhalation valve; determining a set pressure of the exhalation valve based on the measured electrical current; determining a difference between the set pressure and the measured exhalation pressure; based on the difference, estimating exhalation flow through the breathing circuit, estimating the exhalation flow is based on a flow estimation model; and controlling the exhalation valve based on the estimated exhalation flow. ### Claim 2 (depends on 1) The method of claim 1, wherein the operations further comprise training the flow estimation model. ### Claim 3 A ventilator, comprising: a flow sensor comprising a temperature element or a flow element; a pressure sensor; an exhalation valve; a processor; and a memory storing computer executable instructions that when executed by the processor cause the ventilator to perform a set of operations comprising: receiving, from the flow sensor, a measured exhalation flow of breathing gases; receiving, from the pressure sensor, a measured pressure; determining a modeled exhalation flow based on an electrical current provided to an exhalation valve and the measured pressure; evaluating a flow difference between the modeled exhalation flow and the measured exhalation flow; identifying a sensor failure of the flow sensor based on the flow difference and; in response to determining the sensor failure, use the modeled exhalation flow, instead of the measured exhalation flow, for controlling operation of the ventilator. ### Claim 4 (depends on 3) The ventilator of claim 3, wherein the sensor failure is associated with one or more of: the temperature element and the flow element. ### Claim 5 (depends on 4) The ventilator of claim 4, wherein the sensor failure associated with the temperature element is one or more of: a bent thermistor failure and a contaminated sensor failure. ### Claim 6 (depends on 4) The ventilator of claim 4, wherein the sensor failure associated with the temperature element is determined based on the flow difference between the modeled exhalation flow and the measured exhalation flow exceeding a threshold. ### Claim 7 (depends on 3) The ventilator of claim 3, wherein the sensor failure is determined to be a broken hot wire failure based on the measured exhalation flow being a constant value. ### Claim 8 (depends on 3) The ventilator of claim 3, wherein the sensor failure is determined to be a saturated filter failure based on a spike in the flow difference. ### Claim 9 (depends on 3) The ventilator of claim 3, wherein the operations further comprise displaying a failure message indicating the sensor failure. ### Claim 10 (depends on 3) The ventilator of claim 3, wherein determining the modeled exhalation flow is based on a difference between the measured pressure and a set valve pressure of the exhalation valve. ### Claim 11 A ventilator, comprising: a flow sensor; a pressure sensor; an exhalation valve; a processor; and a memory storing computer executable instructions that when executed by the processor cause the ventilator to perform a set of operations comprising: measuring an exhalation flow using the flow sensor; measuring an exhalation pressure using the pressure sensor; determining a modeled exhalation flow based on an electrical current provided to the exhalation valve and the measured exhalation pressure; evaluating a flow difference between the measured exhalation flow and the modeled exhalation flow; generating a weighted average flow based on the measured exhalation flow, the modeled exhalation flow, and the flow difference; and using the weighted average flow to control the ventilator to deliver positive pressure ventilation. ### Claim 12 (depends on 11) The ventilator of claim 11, wherein determining the modeled exhalation flow comprises using a flow estimation model trained to determine the modeled exhalation flow. ### Claim 13 (depends on 11) The ventilator of claim 11, wherein the operation of generating the weighted average flow is based on a determination that the flow difference exceeds a threshold value.