A Wearable, Wireless, and Long Lifetime Device to Detect Sleep Disorder Diseases

摘要

Sleep disorder disease (SDA) and sleep apnoeas are, at this moment, very common pathologies that affect at least 25% of the worldwide population. The method to investigate this disease is expensive, complicated, and needs hospitalization of patients. For these reasons, most cases remain undiagnosed. A comfortable wireless device has been designed to detect the main parameters of SDA as respiration rate (RR), time of apnea (TA), and activation of the autonomous central nervous system (SNA). The device consists of two simple sensors; a thermistor placed close to the nose, which detects the changing in airflow during breathing, and a galvanic skin response (GSR) sensor, which measures the conductivity of the skin. The information is extracted by a low power microcontroller, which calculates RR, TA and the activation of the SNA. The information is collected by a smartphone using the low energy Bluetooth feature to guarantee a long lifetime to the device that uses a small coin battery. Different algorithms are described to minimize the payload on the connection, and therefore power consumption too. The amount memory used to store data on the smartphone is approximately 0.01% compared to a continuous recording.