Abstract
Continuous overnight vital signs monitoring would be ideal for patients suffering from epilepsy, where life-threatening hypoxemias can occur during sleep. However, the existing physiological monitoring systems suffer from limitations in terms of usability factors and/or limited information of the signals being acquired. The body location of the monitoring system is a crucial consideration, seldom addressed by the wider community. This article presents a proof-of-concept, neck-worn photoplethysmography system, which was developed and tested to assess the feasibility of the neck as a monitoring site for longitudinal sensing of cardiac and respiratory responses during sleep. The novel system was compared against a gold-standard commercial multichannel cardiorespiratory polysomnography (PSG) system during oxygen desaturation cycles, to assess its ability to measure heart rate, respiratory rate (RR), and peripheral blood oxygen saturation (SpO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) on 15 participants. The findings for heart rate showed a marginal mean error of 0.47 beats/min with limits of agreement (LOA) at 95% confidence between -3.17 and 4 bpm. RR comparisons had an overall mean error of 0.43 breaths/min, with LOA at 95% confidence between -2.73 and 3.3 bpm. Lastly, the system accurately outputs SpO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> with an overall root-mean-square error of 1.44% between 90 and 100% SpO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> using a custom calibration method. Moreover, it was observed that the neck made it possible for the system to detect desaturation events on an average 12.6 s prior to the PSG system, which used a peripheral finger-based PPG system. Ultimately, this proof-of-concept study illustrates the viability of neck-based sensing for minimally invasive monitoring of cardiac and respiratory vitals during sleep.
Highlights
E PILEPSY is a neurological condition affecting the central nervous system, resulting in bursts of electrical activity in the brain, resulting in seizures with a variety of physical and/or cognitive manifestations [1]
The Bland–Altman and scatter plots were used to assess the agreement between the Neck Worn PPG System (NWPPGS) and SOMNOScreen for heart rate (HR), respiratory rate (RR), and SpO2
The overall Root-mean-square error (RMSE) (ORMSE) was obtained by averaging individual RMSE j for all subjects based on the sample size for each subject
Summary
E PILEPSY is a neurological condition affecting the central nervous system, resulting in bursts of electrical activity in the brain, resulting in seizures with a variety of physical and/or cognitive manifestations [1]. The disease affects more than 500 000 people in the U.K. and 50 million worldwide [2]. It is Manuscript received February 19, 2021; revised April 11, 2021; accepted April 26, 2021. Date of publication May 26, 2021; date of current version June 10, 2021. The Associate Editor coordinating the review process was Dr Subhas Chandra Mukhopadhyay. The Associate Editor coordinating the review process was Dr Subhas Chandra Mukhopadhyay. (Corresponding author: Sukhpreet Singh.)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
