Intranasal Fentanyl versus Subcutaneous Fentanyl for Pain Management in Prehospital Patients with Acute Pain: A Retrospective Analysis.

: Retrospective analysis evaluating and comparing the feasibility, effectiveness and safety of intranasal fentanyl (INF) and subcutaneous fentanyl (SCF) for pain management of patients with acute severe pain in a rural/suburban Emergency Medical Services (EMS) system. : Pre- and post-pain management data of all patients (aged ≥14 years) who were transported to the emergency department (January 2015-August 2017) were extracted from EMS and online medical control center records, and compared for groups receiving INF or SCF. Kaplan-Meier analysis and the log-rank test were used to describe and compare the percentage of patients in both groups who experienced relief according to their clinically significant pain relief score. Subgroup analysis was performed by patient age (<70 years, ≥70 years). : 94.6% (SCF = 94.8%; INF = 94.4%) of patients successfully received fentanyl and 82.7% (SCF = 81.2%; INF = 84.0%) had complete data and were included in the analysis. No difference was observed in time to administration or in the effectiveness of INF and SCF, and neither route of administration resulted in major adverse events that required intervention by paramedics. Upon subgroup analysis, INF patients ≥70 years were more likely to experience relief compared to those <70 years. : This retrospective analysis of prehospital patients in the Chaudière-Appalaches EMS system demonstrates that both IN and SC are feasible, effective and safe routes for administering fentanyl. The observed effects of INF were found to be greater among patients ≥70 years. Further research is required to compare these routes with more conventional methods of pain management.