Fentanyl versus nebulized ketamine for prehospital analgesia: A retrospective data review

To evaluate the comparative effectiveness of fentanyl and ketamine via Breath Actuated Nebulizer (BAN) for analgesia in the prehospital setting.

We conducted a retrospective cross-sectional evaluation of patients receiving fentanyl or ketamine via BAN for pain management in a large suburban EMS system between 3/1/2022 and 6/1/2023. The primary outcome was change in first to last pain score. Subgroup analysis was performed on patients with traumatic pain. We used inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) to estimate the treatment effect of fentanyl vs ketamine via BAN among all patients and the subgroup of those with traumatic pain.

Of the total 1480 patients included, 1317 (89.0 %) received fentanyl and 163 (11.0 %) received ketamine via BAN. The unadjusted mean change in pain score was -2.9 (SD 3.0) for fentanyl and -3.5 (SD 3.4) for ketamine. In the propensity score analyses, there was no statistically significant difference in pain score change for the fentanyl group versus ketamine among all patients (mean difference, IPTW: -0.45, 95 %CI -1.18, 0.28; PSM: -0.36, 95 %CI -0.93, 0.21). Subgroup analysis of patients treated for traumatic pain showed a significant reduction in pain for patients treated with ketamine compared to fentanyl, indicating a higher degree of analgesia from ketamine for traumatic pain (unadjusted: -1.37, 95 % CI -2.20, -0.54; IPTW: -1.10, 95 % CI -1.96, -0.23; PSM: -0.92, 95 % CI -1.17, -0.12).

We found no statistically significant difference in the analgesic treatment effect for the overall fentanyl and ketamine groups. Subgroup analysis of patients treated for traumatic pain showed greater analgesia for ketamine via BAN over fentanyl. Given the ease of administration and lack of need for intravenous access, ketamine via BAN is a reasonable and effective choice for prehospital pain management.