Experiment with Cuffless Estimation of Arterial Blood Pressure from the Signal Sensed by the Optical PPG Sensor

Abstract

The paper describes the development, testing, and verification of practical usability of the indirect cuffless method for estimation of arterial blood pressure (ABP) values from the photo-plethysmography (PPG) signal sensed by the optical PPG sensor. The proposed procedure uses time domain features (systolic/diastolic pulse time ratios and partial areas around the pulses) extracted from the second derivative of the PPG signal. The linear regression method is next used to calculate the relation between the determined PPG wave features and the blood pressure values measured in parallel using a blood pressure monitor. ABP values are finally estimated by the inverse conversion characteristic calculated from these linear relations. Summary estimation errors obtained from first-step experiments achieve acceptable values of about 8/3% for systolic/diastolic ABPs. However, further improvements are necessary before usage of the proposed procedure.

Keywords

• arterial blood pressure
• estimation by linear regression
• photoplethysmography signal
• PPG sensor working in a reflectance mode