# US 10,499,818 B2 · System and method for providing blood pressure safe zone indication during autoregulation monitoring > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,499,818 B2 - Document ID: US10499818B2 - Status: Granted - Kind: B2 - Application number: 15/296,150 - Filed: 2016-10-18 - Published: 2017-04-20 - Granted: 2019-12-10 - Earliest claimed: 2015-10-19 - Assignees: Covidien LP - Applicants: Covidien LP - Inventors: Paul Stanley Addison; James N. Watson; Dean Montgomery - Web page: https://patentgrep.com/patent/US10499818B2 ## CPC - A61B 5/0205: Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition - A61B 5/02028: {Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction} - A61B 5/021: Measuring pressure in heart or blood vessels - A61B 5/026: Measuring blood flow {(A61B3/1233, A61B3/1241 take precedence)} - A61B 5/14546: {for measuring analytes not otherwise provided for, e.g. ions, cytochromes} - A61B 5/14553: {specially adapted for cerebral tissue} - A61B 5/4064: {Evaluating the brain (for intracranial pressure A61B5/031; for cerebral blood gases A61B5/14553; using EEG A61B5/369)} - A61B 5/7246: {using correlation, e.g. template matching or determination of similarity} - A61B 5/742: {using visual displays (displays for heart-related electrical signals, e.g. ECG, A61B5/339)} - A61B 5/7425: {Displaying combinations of multiple images regardless of image source, e.g. displaying a reference anatomical image with a live image} - A61B 5/743: {Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots} - G16H 40/63: for local operation - G16H 50/20: for computer-aided diagnosis, e.g. based on medical expert systems - G16H 50/30: for calculating health indices; for individual health risk assessment - A61B 5/0059: {using light, e.g. diagnosis by transillumination, diascopy, fluorescence (photoacoustic A61B5/0093; optical measurement of heart rate A61B5/02416; optical measurement of blood flow A61B5/0261; optical measurement of analytes A61B5/1455)} - A61B 5/0261: {using optical means, e.g. infrared light} - A61B 5/031: {Intracranial pressure} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A method for monitoring autoregulation includes, using a processor, using a processor to execute one or more routines on a memory. The one or more routines include receiving one or more physiological signals from a patient, determining a correlation-based measure indicative of the patient's autoregulation based on the one or more physiological signals, and generating an autoregulation profile of the patient based on autoregulation index values of the correlation-based measure. The autoregulation profile includes the autoregulation index values sorted into bins corresponding to different blood pressure ranges. The one or more routines also include designating a blood pressure range encompassing one or more of the bins as a blood pressure safe zone indicative of intact regulation and providing a signal to a display to display the autoregulation profile and a first indicator of the blood pressure safe zone. ## Claims ### Claim 1 A monitor for monitoring autoregulation, the monitor comprising: a display; a memory encoding one or more processor-executable instructions; and one or more processors configured to access and execute the one or more instructions encoded by the memory, wherein the instructions, when executed, cause the one or more processors to: receive one or more physiological signals from a patient; determine a correlation-based measure indicative of an autoregulation of the patient based on the one or more physiological signals; generate an autoregulation profile of the patient based on autoregulation index values of the correlation-based measure, wherein the autoregulation profile comprises the autoregulation index values sorted into bins corresponding to different blood pressure ranges; designate a blood pressure range encompassing one or more of the bins as a blood pressure safe zone indicative of intact autoregulation; provide a first signal to the display to display the autoregulation profile and a first indicator of the blood pressure safe zone; and provide a second signal to the display to display a second indicator of a target blood pressure within the blood pressure safe zone for the patient. ### Claim 2 (depends on 1) The monitor of claim 1, wherein the correlation-based measure is one of a cerebral oximetry index, a hemoglobin volume index, or a mean velocity index. ### Claim 3 (depends on 1) The monitor of claim 1, wherein the one or more instructions, when executed, cause the one or more processors to: receive patient specific inputs, the patient specific input being physical characteristics of the patient, wherein the instructions to designate the blood pressure range encompassing one or more of the bins as the blood pressure safe zone indicative of intact autoregulation comprise instructions to designate the blood pressure range encompassing one or more of the bins as an initial blood pressure safe zone indicative of intact autoregulation utilizing at least historical population data based on the patient specific inputs, and wherein the instructions to provide the first signal to the display comprise instructions to provide a signal to display an indicator of the initial blood pressure safe zone. ### Claim 4 (depends on 3) The monitor of claim 3, wherein the instructions to designate the blood pressure range encompassing one or more of the bins as the initial blood pressure safe zone indicative of intact autoregulation comprise instructions to designate the blood pressure range as the initial blood pressure safe zone utilizing both the historical population data based on the patient specific inputs and initially measured baselines of physiological parameters of the patient. ### Claim 5 (depends on 3) The monitor of claim 3, wherein the one or more instructions, when executed, cause the one or more processors to: determine if there is sufficient data within the autoregulation profile to designate a patient-specific blood pressure safe zone; in response to determining that there is sufficient data, subsequently designate the blood pressure range encompassing one or more of the bins as a subsequent patient specific blood pressure safe zone indicative of intact autoregulation utilizing the autoregulation index values and corresponding blood pressure levels; and provide a third signal to the display to display an indicator of the subsequent patient specific blood pressure safe zone. ### Claim 6 (depends on 5) The monitor of claim 5, wherein the indicator of the initial blood pressure safe zone comprises a first color, and wherein the indicator of the subsequent patient specific blood pressure safe zone comprises a second color different from the first color. ### Claim 7 (depends on 1) The monitor of claim 1, wherein the one or more instructions, when executed, cause the one or more processors to: change a color of the second indicator displayed on the display based on a distance of a current blood pressure of the patient derived from the target blood pressure; or change a level of a blip bar displayed on the display based on the distance of the current blood pressure of the patient derived from the target blood pressure. ### Claim 8 (depends on 1) The monitor of claim 1, wherein the one or more instructions, when executed, cause the one or more processors to receive a user input of the target blood pressure. ### Claim 9 (depends on 1) The monitor of claim 1, wherein the one or more physiological signals comprise a regional oxygen saturation signal and a blood pressure signal, wherein the instructions to generate the autoregulation profile comprise instructions to generate a curve from the regional oxygen saturation signal and the blood pressure signal, and wherein the instructions to designate the blood pressure safe zone comprise instructions to: determine both a lower limit (LLA) and an upper limit (ULA) of autoregulation from the curve; and determine the target blood pressure based on the curve. ### Claim 10 (depends on 9) The monitor of claim 9, wherein the instructions to determine the target blood pressure comprise instructions to designate a point equidistant between the LLA and ULA as the target blood pressure. ### Claim 11 (depends on 9) The monitor of claim 9, wherein the one or more instructions, when executed, cause the one or more processors to: determine a first gradient of the curve at a first blood pressure portion of the curve lower than the LLA; and determine a second gradient of the curve at a second blood pressure portion of the curve higher than the ULA, wherein the instructions to determine the target blood pressure comprise instructions to determine the target blood pressure based on the first gradient, the second gradient, or a combination thereof. ### Claim 12 (depends on 9) The monitor of claim 9, wherein the instructions to determine the target blood pressure comprise instructions to designate a point of inflection of the curve as the target blood pressure. ### Claim 13 (depends on 1) The monitor of claim 1, wherein the one or more instructions, when executed, cause the one or more processors to provide a third signal to the display or other output device to provide an audible or visual indication that a current blood pressure of the patient is outside the blood pressure safe zone. ### Claim 14 (depends on 13) The monitor of claim 13, wherein the audible or visual indication comprises a first audible or visual indication that indicates that the current blood pressure is higher than the blood pressure safe zone and a second audible or visual indication that the current blood pressure is lower than the blood pressure safe zone, and wherein the first audible or visual indication is different from the second audible or visual indication. ### Claim 15 (depends on 1) The monitor of claim 1, wherein the instructions to provide the first signal to the display comprise instructions to cause the display to flash the autoregulation profile and the first indicator of the blood pressure safe zone on and off. ### Claim 16 (depends on 1) The monitor of claim 1, wherein the instructions to provide the first signal to the display comprise instructions to provide the first signal to the display to display a blood pressure history of the patient, wherein the blood pressure history depicts an amount of time blood pressure measurements within the bins are within the blood pressure safe zone. ### Claim 17 (depends on 16) The monitor of claim 16, wherein the first indicator of the blood pressure safe zone overlays a portion of the autoregulation profile corresponding to the blood pressure safe zone. ### Claim 18 A method for monitoring autoregulation, the method comprising: receiving, by one or more processors executing one or more instructions encoded on a memory, one or more physiological signals from a patient; determining, by the one or more processors, a correlation-based measure indicative of an autoregulation of the patient based on the one or more physiological signals; generating, by the one or more processors, an autoregulation profile of the patient based on autoregulation index values of the correlation-based measure, wherein the autoregulation profile comprises the autoregulation index values sorted into bins corresponding to different blood pressure ranges; designating, by the one or more processors, a blood pressure range encompassing one or more of the bins as a blood pressure safe zone indicative of intact autoregulation; providing, by the one or more processors and to a display, a signal to display the autoregulation profile and a first indicator of the blood pressure safe zone; and providing, by the one or more processors and to the display, a second signal to display a second indicator of a target blood pressure within the blood pressure safe zone for the patient. ### Claim 19 A monitor for monitoring autoregulation, the monitor comprising: a display; a memory encoding one or more processor-executable instructions; and one or more processors configured to access and execute the one or more instructions encoded by the memory, wherein the instructions, when executed, cause the one or more processors to: receive one or more physiological signals from a patient; determine a correlation-based measure indicative of an autoregulation of the patient based on the one or more physiological signals; generate an autoregulation profile of the patient based on autoregulation index values of the correlation-based measure, wherein the autoregulation profile comprises the autoregulation index values sorted into bins corresponding to different blood pressure ranges; determine if there is sufficient data within the autoregulation profile to designate a patient-specific blood pressure safe zone; in response to determining that there is sufficient data, designate a blood pressure range encompassing one or more of the bins as a patient-specific blood pressure safe zone indicative of intact autoregulation utilizing the autoregulation index values and corresponding blood pressure levels; and provide a first signal to the display to display the autoregulation profile and a first indicator of the patient-specific blood pressure safe zone. ### Claim 20 (depends on 19) The monitor of claim 19, wherein the one or more instructions, when executed, cause the one or more processors to: receive patient specific inputs, the patient specific inputs being physical characteristics of the patient; in response to determining that there is insufficient data, designate the blood pressure range encompassing one or more of the bins as an initial blood pressure safe zone indicative of intact autoregulation utilizing at least historical population data based on the patient specific inputs; and provide a second signal to the display to display an indicator of the initial blood pressure safe zone. ### Claim 21 (depends on 1) The monitor of claim 1, wherein the one or more instructions, when executed, cause the one or more processors to provide a third signal to the display or another output device to provide a visual or audible indication of a distance the current blood pressure is from the target blood pressure.