Portable Noninvasive and Real-time Sympathetic Nerve Activity Measurement Device: Further Validation

Sympathetic nerve activity plays a crucial role in human physiological processes, and its assessment is essential for understanding the etiology and progression of various diseases. However, reliable non-invasive methods for real-time monitoring of human sympathetic nerve activity are still lacking. Simultaneous non-invasive recording of electrocardiogram and skin sympathetic nerve activity (neuECG) is a new method for sympathetic nervous system assessment. We have developed a portable noninvasive neuECG device for measuring skin sympathetic nerve activity (SKNA). Our study demonstrated that SKNA recorded by this device serves as a powerful tool for real-time assessment of sympathetic nerve activity in humans. We validated this method by activating, inhibiting, and reactivating sympathetic nerve activity in ICU patients through pain stimulation, administration of the sedative remifentanil, and lung recruitment, respectively. Furthermore, our research documented circadian rhythm changes in sympathetic nerve activity in ICU patients over a 24-hour period, confirming the device's stability for long-term monitoring. Our findings provide a noninvasive and real-time method for assessing sympathetic nerve activity, which is of great significate to both clinical research and patient care.