# US 12,178,556 B2 · Apparatus for use with a wearable cuff > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,178,556 B2 - Document ID: US12178556B2 - Status: Granted - Kind: B2 - Application number: 17/279,646 - Filed: 2019-09-23 - Published: 2021-11-04 - Granted: 2024-12-31 - Earliest claimed: 2018-09-26 - Assignees: Koninklijke Philips N.V. - Applicants: Koninklijke Philips N.V. - Inventors: Maarten Petrus Joseph Kuenen - Web page: https://patentgrep.com/patent/US12178556B2 ## CPC - A61B 5/02141: {Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits (A61B5/02233, A61B5/0235 take precedence)} - A61B 5/022: by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers - A61B 5/02208: {using the Korotkoff method} - A61B 5/02225: {using the oscillometric method} - A61B 2503/045: Newborns, e.g. premature baby monitoring - A61B 2503/06: Children, e.g. for attention deficit diagnosis - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract There is provided an apparatus (12) for use with a wearable cuff (14) in measuring blood pressure. The cuff (14) is inflatable to pressurize a measurement site (20) of a subject (18). The apparatus (12) is configured to estimate a size of the cuff (14) during a current inflation of the cuff (14) and compare the estimated size of the cuff (14) to a previous size of the cuff (14) estimated during an inflation of the cuff (14) that immediately preceded the current inflation of the cuff (14). The apparatus (12) is also configured to, if the estimated size of the cuff (14) differs from the previous size of the cuff (14) by more than a predefined amount, change a pressure up to which the cuff (14) is inflated before deflation of the cuff (14) starts. ## Claims ### Claim 1 An apparatus for use with a wearable cuff in measuring blood pressure, wherein the cuff is inflatable to pressurize a measurement site of a subject and the apparatus is configured to: estimate a size of the cuff during a current inflation of the cuff; compare the estimated size of the cuff to a previous size of the cuff estimated during an inflation of the cuff that immediately preceded the current inflation of the cuff; and when the estimated size of the cuff differs from the previous size of the cuff by more than a predefined amount, change a pressure up to which the cuff is inflated before deflation of the cuff starts. ### Claim 2 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to change the pressure up to which the cuff is inflated before deflation of the cuff starts based on the estimated size of the cuff. ### Claim 3 (depends on 2) The apparatus as claimed in claim 2, wherein the apparatus is configured to change the pressure up to which the cuff is inflated before deflation of the cuff starts based on the estimated size of the cuff by being configured to: determine an expected blood pressure range for the subject based on the estimated size of the cuff; and change the pressure up to which the cuff is inflated before deflation of the cuff starts based on the determined expected blood pressure range for the subject. ### Claim 4 (depends on 3) The apparatus as claimed in claim 3, wherein the apparatus is configured to determine the expected blood pressure range for the subject based on the estimated size of the cuff by being configured to: compare the estimated size of the cuff to a plurality of reference sizes of the cuff, each stored with a corresponding reference blood pressure range; and determine the expected blood pressure range for the subject as the reference blood pressure range that is stored with the reference size of the cuff that is the same as or differs the least from the estimated size of the cuff. ### Claim 5 (depends on 4) The apparatus as claimed in claim 4, wherein the plurality of reference sizes of the cuff and corresponding reference blood pressure ranges are based on data acquired from a population. ### Claim 6 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to: when the estimated size of the cuff differs from the previous size of the cuff by less than the predefined amount or when the estimated size of the cuff is the same as the previous size of the cuff, determine the pressure up to which the cuff is inflated before deflation of the cuff starts based on a blood pressure value determined during a deflation of the cuff that immediately preceded the current inflation of the cuff. ### Claim 7 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to estimate the size of the cuff during the current inflation of the cuff based on a time taken for the cuff to be inflated from a baseline pressure up to a predefined pressure. ### Claim 8 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to estimate the size of the cuff during the current inflation of the cuff based on an average speed at which the cuff inflates. ### Claim 9 (depends on 8) The apparatus as claimed in claim 8, wherein the apparatus is configured to: determine the average speed at which the cuff inflates as the average speed at which the cuff inflates once a predefined time period after a start of the current inflation of the cuff has passed. ### Claim 10 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to estimate the size of the cuff during the current inflation of the cuff based on an internal volume of the cuff. ### Claim 11 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to estimate the size of the cuff during the current inflation of the cuff based on a volume of fluid into the cuff and a maximum pressure up to which the cuff is inflated. ### Claim 12 (depends on 1) The apparatus as claimed in claim 1, wherein the apparatus is configured to estimate the size of the cuff during the current inflation of the cuff based on a measure of a compliance of the cuff. ### Claim 13 (depends on 1) A system for use in measuring blood pressure, the system comprising: the apparatus as claimed in claim 1; and the cuff that is inflatable to pressurize the measurement site of the subject. ### Claim 14 A method of operating an apparatus for use with a wearable cuff in measuring blood pressure, wherein the cuff is inflatable to pressurize a measurement site of a subject, the method comprising: estimating a size of the cuff during a current inflation of the cuff; comparing the estimated size of the cuff to a previous size of the cuff estimated during an inflation of the cuff that immediately preceded the current inflation of the cuff; and based on the estimated size of the cuff differing from the previous size of the cuff by more than a predefined amount, changing a pressure up to which the cuff is inflated before deflation of the cuff starts. ### Claim 15 In an apparatus for use with a wearable cuff in measuring blood pressure, a computer program product comprising a non-transitory computer readable medium, the non-transitory computer readable medium having computer readable code stored therein, the computer readable code being configured such that, when executed by a computer or a processor, the computer readable code causes the computer or processor to: estimate a size of the cuff during a current inflation of the cuff; compare the estimated size of the cuff to a previous size of the cuff estimated during an inflation of the cuff that immediately preceded the current inflation of the cuff; and when the estimated size of the cuff differs from the previous size of the cuff by more than a predefined amount, change a pressure up to which the cuff is inflated before deflation of the cuff starts. ### Claim 16 (depends on 15) The computer program product as claimed in claim 15, wherein the computer readable code further causes the computer or processor to change the pressure up to which the cuff is inflated before deflation of the cuff starts based on the estimated size of the cuff. ### Claim 17 (depends on 16) The computer program product as claimed in claim 16, wherein the computer readable code further causes the computer or processor to change the pressure up to which the cuff is inflated before deflation of the cuff starts based on the estimated size of the cuff by: determining an expected blood pressure range for a subject based on the estimated size of the cuff; and changing the pressure up to which the cuff is inflated before deflation of the cuff starts based on the determined expected blood pressure range for the subject. ### Claim 18 (depends on 17) The computer program product as claimed in claim 17, wherein the computer readable code further causes the computer or processor to determine the expected blood pressure range for the subject based on the estimated size of the cuff by: comparing the estimated size of the cuff to a plurality of reference sizes of the cuff, each stored with a corresponding reference blood pressure range; and determining the expected blood pressure range for the subject as the reference blood pressure range that is stored with the reference size of the cuff that is the same as or differs the least from the estimated size of the cuff. ### Claim 19 (depends on 18) The computer program product as claimed in claim 18, wherein the plurality of reference sizes of the cuff and corresponding reference blood pressure ranges are based on data acquired from a population. ### Claim 20 (depends on 16) The computer program product as claimed in claim 16, wherein the computer readable code further causes the computer or processor to: when the estimated size of the cuff differs from the previous size of the cuff by less than the predefined amount or when the estimated size of the cuff is the same as the previous size of the cuff, determine the pressure up to which the cuff is inflated before deflation of the cuff starts based on a blood pressure value determined during a deflation of the cuff that immediately preceded the current inflation of the cuff.