Wearable Biosensors for Continuous Monitoring in the Post-Anesthesia Care Unit

Abstract

Post-anesthesia care unit (PACU) monitoring has traditionally relied on intermittent, nurse-driven vital-sign checks, a model that struggles to detect the gradual, often nocturnal onset of hypoventilation and hypoxemia associated with residual anesthetic and opioid effects. Wearable biosensors, including photoplethysmography-based chest patches, arm bands, and in-ear devices, have emerged as a means of providing continuous, cableless surveillance through the PACU stay and across the vulnerable transition to the surgical ward. Validation studies indicate reasonable agreement between these devices and reference monitors for heart rate, oxygen saturation, and respiratory rate, while cuffless blood pressure estimation remains comparatively immature, and observational and meta-analytic data link continuous monitoring to earlier detection of deterioration and fewer opioid-induced respiratory depression events. The principal unresolved challenges lie less in sensor accuracy than in translating continuous data streams into well-calibrated clinical alerts that avoid alarm fatigue and integrate into existing nursing and rapid-response workflows, an area where ongoing randomized trials are expected to clarify outcome benefit. This review synthesizes the current evidence on wearable biosensor technology, validation, and implementation in perioperative recovery, and identifies where further prospective research is most needed.