Home Monitoring of High-Risk Individuals Receiving Opioids Post Orthopedic Surgery

Background: Postoperative patients receiving opioids are at risk for morbidity and mortality caused by opioid-induced respiratory depression (OIRD). Guidelines advocate electronic monitoring for OIRD during postoperative hospitalization, but the utility of home monitoring following ambulatory surgery has not been assessed. We describe the utilization of capnography and pulse oximetry in an ambulatory orthopedic cohort to determine subject/home caregiver acceptance and utility of continuous monitors at home. The specific aims of this initiative were to (1) determine the subject/home caregiver acceptance of home monitoring to detect OIRD in patients after hospital discharge following orthopedic surgery, (2) determine the rate of OIRD and associated morbidity after hospital discharge following orthopedic surgery, and (3) determine patient understanding of the risk of OIRD. Methods: This prospective, subject/home caregiver acceptance quality improvement initiative was conducted from September 28, 2019, to October 31, 2020. Ambulatory subjects undergoing orthopedic surgical procedures had cardiorespiratory data monitored with a commercially available device at home for 4 days while napping/sleeping. Recorded data were analyzed for reliability comparing end-tidal carbon dioxide pressure (P_ETCO2), S_pO2, breathing frequency (f), and heart rate (beats/min). Results: Three hundred fifty-nine subjects were enrolled and had complete data. Two hundred fifty-two (70%) were discharged with supplemental oxygen. When comparing audible alarms with/without delays, there were 4,770/22,409 low P_ETCO2, 1,601/6,246 high P_ETCO2, 460/4,211 low frequency, 1,572/6,547 low heart rate, and 462/5,520 low S_pO2 alarms. Twenty-six (7.2%) subjects visited the emergency department in response to low S_pO2 audible alarms. Of these, 14 (3.9%) were diagnosed with a clinically relevant opioid-induced event, 95% CI 2.1%-6.5%, and 1 subject was administered naloxone by home caregivers. Conclusions: This study demonstrates home monitoring of oxygenation (S_pO2), but not respiration (P_ETCO2), following ambulatory orthopedic procedures is feasible. Subjects at risk for clinically relevant opioid events may experience higher rates of postoperative complications, hospital readmissions, clinically relevant events, or death.