Abstract

Real-time physiological monitoring faces inevitable challenges arising from physical activity accompanying body motion and contact pressure variations, disturbing photoplethysmography (PPG) based monitoring. Opto-physiological modelling (OPM) underpins the radiative transfer theorem (RTT) to reveal the essence of light trans-illumination beyond the standard Beer-Lambert law driving PPG technologies. The principles of OPM have been well established through a new multiwavelength optoelectronic patch sensor (mOEPS) that overcomes drawbacks of present PPG sensors caused by gravity, imbalance, skin tone, thermoregulation, and contact force. A protocol engaging six healthy subjects has been implemented to obtain high-quality pulsatile signals using mOEPS system, and corresponding perfusion indices were computed. Comparative results with two selected clinical grade pulse oximetry probes are presented. The outcomes demonstrate the capability of the mOEPS system to provide real-time and any time physiological monitoring across different variations of skin types (I - VI, Fitzpatrick scale). Upcoming mOEPS validation work against gold-standards will be performed to validate a prospective wearable system for clinical grade monitoring and assessment over continuous physiological statuses.

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