Inventors:
Michael Edward Luna - Broadmoor Village CA, US
Thomas Alan Donaldson - Drews Cottage, GB
John M. Stivoric - Pittsburgh PA, US
Sidney Primas - Palo Alto CA, US
Assignee:
AliphCom - San Francisco CA
International Classification:
A61B 5/0205
A61B 5/11
A61B 5/00
Abstract:
One or more wearable devices may measure real-time blood pressure in a body using signals from multiple sensors including but not limited to a multi-axis accelerometer, a bioimpedance (BI) sensor, a capacitive touch sensor, an electrocardiography sensor (ECG), a ballistocardiograph sensor (BCG), a photoplethysmogram (PPG), a pulse oximetery sensor, and a phonocardiograph sensor (PCG), for example. Accelerometry data (e.g., from a multi-axis accelerometer or BCG sensor) may be used to derive effects of acceleration (e.g., gravity) on changes in blood pressure (e.g., due to changes in blood volume as measured using BI signals). The accelerometry data may be used to determine a baseline value for BI voltage signals that are indicative of diastolic and systolic blood pressure (e.g., in mmHg). Combinations of methods, such as BCG, ECG, PPG, blood pressure Pulse Wave and others may be used to determine pulse transit time (PTT), pulse arrival time (PAT), and pre-ejection period (PET). The wearable devices may be born on one or more body parts, such as the wrist, arm, leg, ankle, neck, chest, thorax, head, and ear.