Comparison of Morphine and Fentanyl For Pain Due to Traumatic Injury in the Emergency Department

Abstract

OBJECTIVES: To compare fixed equianalgesic doses of morphine and fentanyl with regard to analgesic response for patients who presented to the ED with moderate to severe pain. METHODS: A retrospective cohort study of clinical data obtained through patient medical record review. Median pain reduction on the numeric pain scale was compared between the morphine and fentanyl groups. Independent variables of interest included: Age, sex, weight, initial pain score, injury severity, triage severity and injury type. RESULTS: : Pain scores were reported to be worse in the fentanyl group, p= 0.0002. However pain reduction was similar between the groups; median (IQR) of 2 (1-3) and 2 (1-4) in the morphine and fentanyl groups respectively, p= 0.6707. Injuries were more severe in the fentanyl group; injury severity score (ISS) median (IQR) of 5 (1-9) and 9 (3-12), p=0.0312 and more patients in the fentanyl group required additional opioids within 30 min of their first ED opioid dose, 15 (18%) and 31 (37%), p=0.006. CONCLUSION: Patients in both the morphine and fentanyl groups received similar analgesic response. Patients in the fentanyl group had a higher severity of injury, received higher doses of opioids from the EMS, and required the second dose of opioid sooner than patients in the morphine group.