Evaluation of Carotid Artery Blood Pressure Waveform Using a Wearable Ultrasound Patch

This work presents a technique for measuring blood pressure waveform using a lightweight, stretchable, and wearable ultrasound patch. A system containing ultrasound transceiver hardware and signal processing software was developed for blood pressure waveform evaluation. By acquiring echo frames from 3 to 4 adjacent arterial locations and employing peak tracking techniques, stable arterial distension waveforms were evaluated. The time delay between channels was utilized to determine local pulse wave velocity (PWV) and arterial compliance, followed by the calculation of arterial blood pressure waveform based on arterial diameter. This technology has been validated on the carotid arteries of 10 human subjects, and the blood pressure waveform measured by the ultrasound patch demonstrated good consistency when compared with the arterial tonometer. The current results indicate that the wearable ultrasound patch can measure blood pressure waveform at central artery sites.