Does intramuscular ondansetron have an effect on intramuscular ketamine-associated vomiting in children? A prospective, randomized, double blind, controlled study.

Objective: This study was conducted to determine the effect of intramuscular ondansetron on ketamine-associated vomiting in children undergoing procedural sedation.

Methods: This randomized, double-blind, placebo-controlled, parallel-group clinical trial was conducted at the emergency departments of two university-affiliated tertiary care hospitals. Eligible participants included all 6-month to 16-year-old children who received IM ketamine for PSA in the ED. A convenience sampling approach was used and a block randomization method was applied (blocks of four) using a computer-generated random sequence. Patients received ketamine 4 mg/kg or ketamine 4 mg/kg plus ondansetron 0.1 mg/kg intramuscularly. All findings including the occurrence of vomiting and its frequency were then recorded in the data collection sheets.

Results: Of 56 patients who received ondansetron plus ketamin, 7 (12.5%) and 1 (1.8%) experienced vomiting during recovery and before discharge and Of 65 patients in the control group, 14 (21.5%) and 6 (9.2%) experienced vomiting during recovery and before discharge, respectively. The observed differences in the rates of vomiting during recovery and at discharge were statistically significant between the two groups (P-value of 0.03 and <0.001, respectively).

Conclusion: Intramuscular ondansetron is effective in controlling ketamine-associated vomiting.