# US 10,945,661 B2 · Physiological feedback systems and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,945,661 B2 - Document ID: US10945661B2 - Status: Granted - Kind: B2 - Application number: 15/960,324 - Filed: 2018-04-23 - Published: 2018-10-25 - Granted: 2021-03-16 - Earliest claimed: 2017-04-21 - Assignees: Physio-Control, Inc. - Applicants: Physio-Control, Inc. - Inventors: Robert G. Walker; Fred W. Chapman - Web page: https://patentgrep.com/patent/US10945661B2 ## CPC - A61B 5/486: {Biofeedback (using electroencephalography [EEG] A61B5/375)} - A61B 5/0836: {Measuring rate of CO2 production} - A61B 5/14551: {for measuring blood gases} - A61B 5/4836: {Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence)} - A61H 31/004: {Heart stimulation} - A61H 31/005: {with feedback for the user} - A61B 5/0002: {Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network (endoradiosondes A61B5/07)} - A61B 5/0205: Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition - A61B 5/085: Measuring impedance of respiratory organs or lung elasticity - A61B 5/7275: {Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor} - A61B 5/742: {using visual displays (displays for heart-related electrical signals, e.g. ECG, A61B5/339)} - A61H 2201/501: connected to external computer devices or networks - A61H 2230/045: used as a control parameter for the apparatus - A61H 2230/065: used as a control parameter for the apparatus - A61N 1/36521: {the parameter being derived from measurement of an electrical impedance} - A61N 1/37: Monitoring; Protecting - A61N 1/3904: {External heart defibrillators [EHD]} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61H: PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY (electrotherapy, magnetotherapy, radiation therapy or ultrasound therapy A61N) - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## Abstract The disclosed physiological feedback systems and methods assist with assessing, monitoring and/or treating a patient experiencing a cardiac arrest event. The systems and methods receive multiple inputs and are continuous and/or iterative during a treatment session to provide physiological state trends of the patient. An index of the physiological state of the patient can be derived and confounders, and/or their effects, can be identified, and/or removed, from the index. Additionally, the systems and methods can assist with determining ischemic injury in a patient based on cerebral tissue oxygenation and/or other physiological data. ## Claims ### Claim 1 A medical device, comprising: a processor configured to: receive physiological parameter data comprising measurements of physiological parameters of a patient, determine an effectiveness index based at least in part on a positive correlation between the physiological parameters in the physiological parameter data, the effectiveness index being indicative of a hemodynamic adequacy of the patient; generate an instruction to alter a treatment of the patient based at least in part on the effectiveness index; and output the instruction. ### Claim 2 (depends on 1) The medical device of claim 1, wherein the measurements comprise transthoracic impedance measurements, electrocardiogram (ECG) measurements, blood pressure measurements, blood flow measurements, cardiac performance measurements, or cardiopulmonary resuscitation (CPR) measurements. ### Claim 3 (depends on 1) The medical device of claim 1, wherein the processor is further configured to receive confounder data and to output the confounder data. ### Claim 4 (depends on 3) The medical device of claim 3, wherein the confounder data indicates an administration of a medication to the patient, an observation of a behavior of the patient, or an administration of the treatment to the patient. ### Claim 5 (depends on 1) The medical device of claim 1, wherein the processor is further configured to receive confounder data and to determine the effectiveness index based at least in part on the confounder data. ### Claim 6 (depends on 1) The medical device of claim 1, wherein the processor is further configured to iteratively determine the effectiveness index. ### Claim 7 (depends on 1) The medical device of claim 1, wherein the physiological parameter data comprises oxygenation data, and wherein the processor is further configured to calculate an oxygenation trend based at least in part on the oxygenation data and to determine the effectiveness index based at least in part on the oxygenation trend. ### Claim 8 (depends on 7) The medical device of claim 7, wherein the processor is further configured to identify a trajectory of the oxygenation trend and to determine the effectiveness index based at least in part on the trajectory. ### Claim 9 (depends on 8) The medical device of claim 8, wherein the processor is further configured to identify, based at least in part on the trajectory, a return of spontaneous circulation (ROSC) of the patient, a likelihood of ROSC of the patient, or a re-arrest of the patient. ### Claim 10 (depends on 1) The medical device of claim 1, wherein the processor is further configured to calculate a physiological parameter trend based at least in part on the physiological parameter data and to determine the effectiveness index based at least in part on the physiological parameter trend. ### Claim 11 (depends on 1) The medical device of claim 1, wherein the processor is further configured to identify, based at least in part on the effectiveness index, a return of spontaneous circulation (ROSC) of the patient, a likelihood of ROSC of the patient, or a re-arrest of the patient. ### Claim 12 (depends on 1) The medical device of claim 1, wherein the processor outputs the instruction by transmitting the instruction to a display. ### Claim 13 (depends on 1) The medical device of claim 1, wherein the processor is further configured to transmit the effectiveness index to a computing device. ### Claim 14 A medical device, comprising: multiple patient sensors configured to generate physiological parameter data by measuring respective multiple physiological parameters of a patient, the multiple patient sensors comprising an oxygenation sensor that is configured to sense tissue oximetry measurements of the patient or an airway CO2 sensor configured to sense capnography measurements of the patient; a processor electrically coupled to the multiple patient sensors and configured to receive the physiological parameter data, the processor further configured to: determine an effectiveness index based at least in part on a positive correlation between the physiological parameters in the physiological parameter data, the effectiveness index being indicative of a hemodynamic adequacy of the patient; generate an instruction to alter a treatment of the patient based at least in part on the effectiveness index; and output the instruction. ### Claim 15 (depends on 14) The medical device of claim 14, wherein the processor is further configured to receive confounder data indicating an administration of a medication to the patient, an observation of a behavior of the patient, or an administration of the treatment to the patient and to determine the effectiveness index based at least in part on the confounder data. ### Claim 16 (depends on 14) The medical device of claim 14, wherein the processor is further configured to calculate a physiologic trend based on the tissue oximetry measurements or the capnography measurements and to determine the effectiveness index based at least in part on the physiologic trend. ### Claim 17 (depends on 16) The medical device of claim 16, wherein the processor is further configured to identify a trajectory of the physiologic trend and to determine the effectiveness index based at least in part on the trajectory. ### Claim 18 (depends on 14) The medical device of claim 14, wherein the processor is further configured to identify, based at least in part on the effectiveness index, a return of spontaneous circulation (ROSC) of the patient, a likelihood of ROSC of the patient, or a re-arrest of the patient. ### Claim 19 A method, comprising: generating, by multiple sensors, physiological parameter data comprising oxygenation measurements of a patient and CO2 measurements of the patient, determining, by a processor, an effectiveness index based at least in part on a positive correlation between the oxygenation measurements and the CO2 measurements, the effectiveness index being indicative of a hemodynamic adequacy of the patient; generating, by the processor, an instruction to alter a cardiopulmonary resuscitation (CPR) treatment of the patient based at least in part on the effectiveness index; and outputting, by a display, the instruction and the effectiveness index. ### Claim 20 (depends on 19) The method of claim 19, further comprising: identifying, by the processor and based at least in part on the effectiveness index, a return of spontaneous circulation (ROSC) of the patient; and outputting, by the display, an alert indicating the ROSC.