UCLA

Statement of the Problem. Approximately 2.5 million individuals suffer traumatic injuries that demand admission to an acute care hospital. Safe, effective pain management is a priority of care for hospitalized patients receiving opioids for acute trauma-related pain. Opioids remain the primary approach for management of moderate to severe pain. The persistent use of an opioid-only approach to pain management is alarming given that an estimated 0.3% to 46% of hospitalized patients receiving opioids experience serious opioid-related adverse events, such as life-threatening respiratory depression. Opioid-induced respiratory depression (OIRD) among trauma patients hospitalized on general care floors had not been previously described. In this preliminary analysis the incidence and characteristics of OIRD monitored by continuous capnography and pulse oximetry, as well as, nursing assessment is reported. Methods. From July through October 2019 patients who presented to the emergency department following traumatic injury and admitted to general care floors were continuously monitored with bedside capnography and pulse oximetry for signs of respiratory depression. The Principal Investigator (PI), an advanced practice registered nurse with expertise in pain management and critical care, also assessed every patient within 5 minutes prior to opioid administration and every 10 minutes for 60 minutes thereafter. The adjusted Wald method was used to calculate the incidence of respiratory depression. STOP-BANG and PRODIGY risk scores were calculated. Time of admission to the ward and time of first OIRD were determined and displayed on a 24-hour radar plot for visual inspection of peak occurrence of events. Summary of findings. Nineteen patients were admitted for a traumatic injury to a general care floor and underwent continuous monitoring with capnography and pulse oximetry. Indications for admission were orthopedic trauma (n=15), chest trauma (n=3), or abdominal (n=1) trauma. Twelve patients required surgical management. High-risk STOP-BANG and PRODIGY scores were calculated for 5 (26.3%) and 8 (42.1%) patients, respectively. The median duration of monitoring was 7.0 [6.4, 7.4] hours. All patients received intravenous opioids in the emergency department and general care floors. Median morphine equivalents in the emergency department were 17.5 MME (IQR 24) and 18MME (IQR 24) for patients who later experienced >1 respiratory event on the GCF as compared to those patients who did not experience a respiratory event on the GCF. Median morphine equivalents (MME) on the general care floor were 7 MME (IQR 8) and 7 MME (IQR 3.5) for patients with >1 respiratory depression event or without, respectively. Respiratory depression was detected in 14 patients (incidence 71 [95%CI 50.9 – 88.6] cases per 100 patients) with apnea (n=12) and hypoxemia (n=10) the most detected abnormalities and hypopnea (n=5) and low expired end-breath carbon dioxide level (n=4) less common. The median time to first detected OIRD was 108 (24, 275) minutes. Majority of admissions were between 1600 and 2400 (n=9, 64%) and the majority of first OIRD episodes were from 1800 to 2400 (n=9, 64%). 42.8% (n=6) of respiratory events occurred prior to the administration of intravenous or oral opioids on the general care ward. Using the Pasero Opioid-Induced Sedation Scale, sedation was observed in 78% (n=11) of patients. Fifty percent (n=7) of respiratory events were recognized by the PI. No patient received an opioid receptor antagonist (naloxone) or was transferred to a higher level of care. Conclusion. These findings revealed that respiratory depression detected by bedside capnography and pulse oximetry was common among trauma patients hospitalized on general care floors. Importantly, OIRD typically was first observed early in the hospital course. Furthermore, respiratory depression and apnea were commonly recognized by changes in exhaled carbon dioxide (ETCO2) and oxygen saturation while undetected with nursing assessment. These results offer compelling evidence of the un-met need for continuous monitoring in this patient population.