Opioid Administration in the Prehospital, Traumatic Injury Setting Rare Despite Efficacy

Patients with major injuries who received prehospital opioids reported decreased pain scores and experienced few adverse events, according to the results of a study published in Injury.

Investigators from Harvard Medical School sourced data for this study from the 2019 National Emergency Medical Services Information System (NEMSIS). Patients (N=3,831,768) who required emergency transfer for an injury were evaluated for prehospital opioid receipt and pain-related outcomes.

The mean age of the study population was 51.5 (standard deviation [SD], 25.4) years, 85.3% of patients had an advanced life support emergency medical service unit dispatched to them, and the median transport time was 16.50 (interquartile range [IQR], 9.05-53.00) minutes. In the prehospital setting, 269,281 patients received opioids, which included fentanyl (88.2%), morphine (11%), hydromorphone (1.7%), and other opioids (0.1%). The median dose was 10 morphine milligram equivalents.

Most patients had an injury severity score of 0 (89.9% for those who received prehospital opioids vs 88.4% of those who did not); 89.3% and 85.1% had a blunt injury, and 3.4% and 4.1% had a penetrating injury, respectively. Median initial pain scores were 9 and 4 points for those receiving prehospital opioids and those who did not, respectively; maximum pain scores were 10 and 4 points, 2.1% and 0.4% received ketamine, and 0.3% and 0.1% received ketorolac (P <.001).

Patients who received prehospital opioids reported a median reduction in pain score of 3 points.

Predictors of receiving prehospital opioids included age, severity of injury, mechanism of injury, location where injury was sustained (urban, suburban, rural, etc), initial pain score, and transport time. The strongest predictor of receiving prehospital opioids was an initial pain score of 10 (odds ratio [OR], 86.14; P <.001), 9 (OR, 48.57; P <.001), and 8 (OR, 35.23; P <.001), respectively. Patients with an injury severity score of 15 or greater (OR, 0.87; P =.002) and with altered mental status (OR, 0.88; P <.001) were less likely to receive prehospital opioids.

Adverse events associated with prehospital opioid administration, including altered mental state and respiratory compromise, were rare (0.2% and 0.1%, respectively).

A major limitation of this study was the lack of data; for example, approximately one-third of patients had either no documented pain score or only 1 pain score documented.

These data indicate that opioids delivered in the prehospital setting to acutely injured patients was associated with reductions in pain scores with few reported adverse events. Despite these trends, few patients receive prehospital opioids even if the patient reports high pain levels from a severe injury. The investigators concluded, “Given the demonstrated effectiveness and low incidence of adverse events associated with opioids in this study, 1 potential intervention to improve the prehospital treatment of pain is to reduce barriers to opioid administration.”