Comparing nebulized ketamine with Entonox for acute traumatic pain in the Emergency Department: A pilot randomized trial

Abstract

Background: In this study, we compared the efficacy, patient satisfaction, and adverse effects of nebulized ketamine to those of Entonox in reducing acute traumatic pain in the Emergency Department. Methods: This was a randomized, single-centre pilot study. Eligible patients were selected from triage and divided into two groups which was nebulized ketamine and Entonox. Nebulized ketamine 50 mg (mean 0.7 mg/kg for an average adult) was administered in a concentration of 5 mL of 10 mg/mL diluted with 1 mL normal saline in a nebulizer. Entonox delivery was self-regulated by the patients. The primary outcome was efficacy of pain reduction according to the visual analogue scale (VAS) in 30 minutes. Adverse effects were monitored in both the groups. Results: A total of 26 patients were divided equally into two groups with n = 13 for each group. Mean reduction in VAS after 5 and 30 minutes was 0.62 ± 0.77 mm and 28.5 ± 12.1 mm for nebulized ketamine and 0.46 ± 0.78 mm and 30 ± 5.8 mm for Entonox. No significant difference was seen in pain reduction (5 min p = 0.616, 30 min p = 0.684). Mean satisfaction with analgesia according to a Likert scale of 1 to 6 was ketamine 4.92 ± 0.64 and Entonox 5.0 ± 0.41 (p = 0.718). No serious adverse events were reported. Conclusion: Nebulized ketamine is a comparable substitute to Entonox in managing acute traumatic pain in the Emergency Department. Further studies are required on the use of inhaled ketamine as an adjunct in managing severe pain and reducing the need for opioids.