Low-cost point-of-care wireless multimodal wearable to monitor vitals and tissue oxygen saturation

Abstract For centuries, infectious diseases have represented a leading cause of global morbidity and mortality, with high transmissibility posing persistent public health challenges. Because early physiological changes often precede overt clinical symptoms, continuous physiological monitoring may provide opportunities for earlier recognition of illness and timely intervention. In this study, we developed and evaluated a wireless wearable device capable of measuring microvascular tissue oxygen saturation, respiratory rate, respiratory rhythm, breathing depth, heart rate, and pulse strength. Device performance was assessed in a clinical study involving healthy participants performing breath-holding, paced breathing, and mild hypercapnia tasks. Breathing rate and heart rate derived from the wearable device were compared with corresponding measurements obtained from commercial physiological monitoring systems. Chest tissue oxygen saturation measured by the wearable device was additionally evaluated alongside peripheral blood oxygen saturation measured using a commercial pulse oximeter. Across all tasks, wearable-derived breathing rate and heart rate demonstrated strong agreement with commercial systems, with small biases (⩽0.19 breaths/min for breathing rate and ⩽0.47 beats/min for heart rate). Chest tissue oxygen saturation exhibited distinct and rapid responses during breath-holding and mild hypercapnia, whereas peripheral oxygen saturation showed delayed or inconsistent changes. During breath-holding, changes in tissue oxygenation preceded peripheral desaturation by approximately 10 s. Collectively, these findings demonstrate the feasibility of the wearable device for real-time, continuous monitoring of cardiorespiratory parameters and microvascular tissue oxygenation, and suggest that tissue-level oxygenation measurements may provide complementary physiological information relevant to early respiratory stress in both general health and infectious disease research contexts.