Review article: Efficacy of prophylactic ondansetron versus placebo or control in reducing vomiting in children undergoing ketamine procedural sedation in the emergency department: A systematic review and meta‐analysis

AbstractKetamine is commonly used for procedural sedation anaesthesia in paediatric patients undergoing painful procedures in the ED. Ketamine's safety profile is excellent, but ketamine‐associated vomiting (KAV) is common. Routine ondansetron prophylaxis could reduce KAV incidence. This literature review evaluated the efficacy of prophylactic ondansetron in reducing KAV incidence. A systematic literature review was performed on databases and trial registries on 14 January 2023 to identify randomised controlled trials. The primary outcome was reduction in KAV incidence, for any route of prophylactic ondansetron, in ED and up to 24 h post‐discharge. ED length of stay, parental satisfaction and time to resumption of normal diet were secondary outcomes. Data analysis was performed using Revman 5.3. Meta‐analysis was performed using random effects modelling. Risk of bias was assessed using the Cochrane Risk‐of‐Bias 2 tool. Evidence quality was assessed using Grading of Recommendation, Assessment Development and Evaluation methodology. Five trials with 920 participants met the eligibility criteria. Prophylactic ondansetron resulted in a reduction in KAV incidence overall odds ratio of 0.51 (95% confidence interval: 0.36–0.73). Intravenous and intramuscular prophylactic ondansetron showed benefit whereas the effect of oral administration was unclear. There was no difference between groups for secondary outcomes overall. The quality of evidence was deemed to be low overall because of high risk of bias and imprecision in outcome measures. This review found low to moderate certainty evidence that prophylactic ondansetron reduces KAV incidence. Methodologically rigorous research, with appropriately timed prophylactic ondansetron based on the route of administration, would further elucidate prophylactic oral ondansetron's efficacy.