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 ₂ ) 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 ₂ with an overall root-mean-square error of 1.44% between 90 and 100% SpO ₂ 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.

中文翻译：

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用于连续生理监测的新型颈挂式可穿戴 PPG 系统概念验证

连续夜间生命体征监测对于癫痫患者来说是理想的选择，因为在睡眠期间可能会发生危及生命的低氧血症。然而，现有生理监测系统在可用性因素和/或所获取信号的有限信息方面受到限制。监控系统的主体位置是一个重要的考虑因素，很少被更广泛的社区解决。本文介绍了一种概念验证、颈戴式光电容积描记系统，该系统经过开发和测试，旨在评估颈部作为纵向监测睡眠期间心脏和呼吸反应的监测部位的可行性。在氧饱和度循环期间，将新系统与黄金标准商业多通道心肺多导睡眠图 (PSG) 系统进行比较， ₂ ) 15 名参与者。心率结果显示边际平均误差为 0.47 次/分钟，在 -3.17 和 4 bpm 之间具有 95% 置信度的一致限 (LOA)。RR 比较的总体平均误差为 0.43 次呼吸/分钟，LOA 在 -2.73 和 3.3 bpm 之间的置信度为 95%。最后，系统准确地输出 SpO ₂，在 90% 到 100% SpO ₂之间的总体均方根误差为 1.44% 使用自定义校准方法。此外，观察到颈部使系统能够在 PSG 系统之前平均 12.6 秒检测到去饱和事件，PSG 系统使用基于外围手指的 PPG 系统。最终，这项概念验证研究说明了基于颈部的传感在睡眠期间对心脏和呼吸生命体征进行微创监测的可行性。