Wireless wearable multi-sensory system for monitoring of sleep apnea and other cardiorespiratory disorders

This paper reports the development of a wireless, wearable, multi-sensor suite and its integration as part of a smart garment for point-of-care diagnosis of cardiorespiratory disorders with a particular focus on sleep apnea screening. The suite is designed to synchronously gather 3-lead vectorcardiogram signals sampled at 250 Hz from a custom-designed hardware, heart sound signals gathered at 250 Hz from a MEMs sound sensor (model MT-201 from ADinstrument), digitized oxygen saturation (SPO₂) signals at 250 Hz (model PC-60B from St. Alban Medical), and respiratory signals. The signals are transmitted to a nearby processing and graphical visualization unit via a Bluetooth module (model RN-800S-CB from Roving Network). The system can serve as an out-of-center Type III sleep apnea screening device. Extensive tests suggest that the quality of the signals is comparable to that of commercial and standard recording systems. While this unit offers enhanced functionality in terms of simultaneous electro- and phonocardiorespiratory analysis, the power consumption rates and diagnostic performance are comparable to those of commercial point-of-care wireless medical devices for cardiorespiratory diagnosis.