Microflotronic arterial tonometry for continuous wearable non-invasive hemodynamic monitoring

Personalized mobile medicine will continue to advance through the development of wearable sensors that can wirelessly provide pertinent health information while remaining unobtrusive, comfortable, low cost, and easy to operate and interpret. It is the intention that the sensor presented hereafter can contribute to such innovation. By applying a combination of emerging microfluidic and electronic technologies, a miniature, flexible, transparent, highly sensitive and wearable pressure sensor with microfluidic elements has been implemented, referred to as a microflotronic device. High sensitivity of 0.1 kPa(-1) and fast response time on the order of tens of milliseconds has been achieved on the microflotronic sensor design. Its sensitivity is among the highest in impedance-based flexible pressure sensors. Once configured into an array, the transparent device can be easily aligned over the target artery to measure blood pressure noninvasively and continuously. In addition, the ultraflexible and thin plastic construct of the microflotronic sensor (of 270 µm in height) can be worn comfortably for extended periods of time. Importantly, the proposed microflotronic sensor has been utilized to perform arterial tonometry with the capability of noninvasive monitoring of arterial blood pressure waveforms in a real-time and continuous fashion.