Wearable Blood Pressure Monitoring Based on Bio-Impedance and Photoplethysmography Sensors on the Arm

Abstract

In this paper, a wearable beat-to-beat blood pressure (BP) monitoring system using the pulse transit time (PTT), based on the bio-impedance (BI) and photoplethysmography (PPG) sensors is proposed. PTT is calculated as the time difference between the pulse signal from the BI sensor and the PPG sensor. To verify the feasibility of the proposed bio-impedance - PPG (BI-PPG) method, experimental measurements have been conducted on 5 young healthy male subjects. The results show that the beat-to-beat pulse wave velocity (PWV) derived from the BI-PPG method is highly correlated with the measured beat-to-beat reference systolic and diastolic BP. Therefore, the proposed method can potentially facilitate the development of beat-to-beat continuous BP monitoring system.