Comparing the analgesic effect of intranasal with intravenous ketamine in isolated orthopedic trauma: A randomized clinical trial

OBJECTIVES: Ketamine is commonly used in anesthetic and sedation before surgical procedures and acts as an analgesic in smaller doses. The aim of this study was to assess the effects of intranasal (IN) ketamine in patients with moderate to severe limb trauma (visual analog scale (VAS) > 60 mm). METHODS: In a triple-blind randomized controlled clinical trial; 154 patients with isolated orthopedic trauma and visual analog scale (VAS) ≥60 mm were included on the basis of inclusion and exclusion criteria. Patients were divided into two groups of ketamine-IN (0.4 mg/kg IN ketamine and an equal volume of placebo saline intravenously (IV)) and ketamine-IV (0.2 mg/kg ketamine IV with 0.5 ml saline IN) on the basis of balanced block randomization method. At 5, 10, 20, and 30 min, patients were assessed for VAS measurement and adverse events. Repeated measure ANOVA, independent t-test and chi square test were employed. The level of statistical significance was considered to be less than 0.05. RESULTS: Mean VAS in IN ketamine and IV group at minute 30 was 31.50 ± 13.40 and 29.35 ± 11.73, respectively. At minute 30, 31 patients (20.39%) required a low-dose of morphine as rescue analgesia (P = 0.427). The results showed that mean change score of VAS (difference of time 0 and time 30) in IN ketamine and IV ketamine VAS were 43.8 (95% confidence interval: 41.1–46.5) and 46.4 (95% confidence interval: 42.8–50.1) and there is no difference between two groups in case of score change of VAS (P = 0.245). Adverse events in nasal and intravenous ketamine in both groups were mild and transient. CONCLUSION: IN ketamine is associated with few side effects and appropriate analgesic effects in isolated orthopedic trauma patients, and it may be used in cases where there is no need for venipuncture of peripheral vessels, especially in crowded EDs.