Comparison of the effects of intravenous premedication: Midazolam, Ketamine, and combination of both on reducing anxiety in pediatric patients before general anesthesia

OBJECTIVE: In some medical circumstances, pediatric patients may need premedication for transferring to the operating room. In these situations, using intravenous premedication is preferred. We assessed the efficacy and safety of intravenous midazolam, intravenous ketamine, and combination of both to reduce the anxiety and improve behavior in children undergoing general anesthesia. METHODS: In a double-blind randomized clinical trial, 90 pediatric patients aged 6 months to 6 years with American Society of Anesthesiologist grade I or II were enrolled. Before anesthesia, children were randomly divided into three groups to receive intravenous midazolam 0.1 mg/kg, or intravenous ketamine 1 mg/kg, or combination of half doses of both. Behavior types and sedation scores were recorded before premedication, after premedication, before anesthesia, and after anesthesia in the postanesthesia care unit. Anesthesia time, recovery duration, blood pressure, and heart rate were also recorded. For comparing distribution of behavior types and sedation scores among three groups, we used Kruskal–Wallis test, and for comparing mean and standard deviation of blood pressure and heart rates, we used analysis of variance. FINDINGS: After premedication, children's behavior was significantly better in the combination group (P < 0.001). After anesthesia, behavior type was same among three groups (P = 0.421). Sedation scores among three groups were also different after premedication and the combination group was significantly more sedated than the other two groups (P < 0.001). CONCLUSION: Combination of 0.05 mg/kg of intravenous midazolam and 0.5 mg/kg of intravenous ketamine as premedication produced more deep sedation and more desirable behavior in children compared with each midazolam 0.1 mg/kg or ketamine 1 mg/kg.