An in vitro wrist blood pressure simulation system showed that wrist oscillometric envelope parameters highly correlate with internal radii and stiffness of the radial and ulnar arteries.
An in vitro wrist blood pressure simulation system demonstrates that pulse-pressure-stratified calibration can improve the accuracy of wrist oscillometric blood pressure measurements.
Accurate determination of systolic and diastolic blood pressure from the oscillometric cuff-pressure oscillation envelope remains a key challenge in daily monitoring. This study aims to design wrist silicone phantoms based on personalized magnetic resonance imaging and to employ an in vitro pulsatile experimental platform to investigate how wrist physiological parameters affect the envelope. Silicone materials with elastic moduli matched to those of wrist soft tissues and arteries were selected, and biomimetic wrist phantoms were fabricated by integrating 3D printing and silicone casting techniques. The image-based silicone wrist phantom was incorporated into an in vitro pulsatile platform to establish an in vitro wrist blood pressure simulation system (IV-WBPSS). Several representative human blood pressure conditions were set in the IV-WBPSS, and the oscillometric envelopes of the simulated wrists were acquired using a modified Omron T31 sphygmomanometer. By comparing the envelope characteristic parameters of silicone and human wrists under identical blood pressure conditions, the physiological relevance of the IV-WBPSS was validated. Further experiments were performed to obtain oscillometric envelopes and their characteristic parameters under various pulse pressure (PP) and arterial stiffness conditions. Results show that the characteristic parameters of the wrist oscillometric envelope are highly correlated with the internal radii and stiffness of the radial and ulnar arteries. The findings also indicate that the general amplitude coefficient exhibits substantial errors in systolic blood pressure (SBP) extraction under conditions of low PP and high PP. To address this limitation, this study proposes a pulse-pressure-stratified calibration method, which involves setting SBP amplitude coefficients by PP groups and can effectively improve the accuracy of wrist oscillometric blood pressure measurement. This study provides new insights into improving the accuracy of wrist oscillometric blood pressure measurement, and the IV-WBPSS offers a useful tool for performance evaluation of wearable medical devices.
Y et al. (Sat,) conducted a other in Blood pressure measurement. In vitro wrist blood pressure simulation system (IV-WBPSS) vs. Human wrists was evaluated on Oscillometric envelope characteristic parameters. An in vitro wrist blood pressure simulation system showed that wrist oscillometric envelope parameters highly correlate with internal radii and stiffness of the radial and ulnar arteries.