Effect of ketamine versus thiopental sodium anesthetic induction and a small dose of fentanyl on emergence agitation after sevoflurane anesthesia in children undergoing brief ophthalmic surgery

BACKGROUND: Emergence agitation (EA) in children after sevoflurane anesthesia is common. The purpose of this study was to compare the incidences of EA between ketamine and thiopental sodium induction in children underwent sevoflurane anesthesia. We also evaluated if a small dose of fentanyl could reduce the incidence of EA. METHODS: The patients who were scheduled for strabismus or entropion surgery were divided into 4 groups. The patients in Groups 1 and 2 were induced anesthesia with ketamine 1.5 mg/kg; those in Groups 3 and 4 were induced with thiopental sodium 5 mg/kg. The patients in Groups 1 and 3 received an injection of fentanyl 1.5 µg/kg, whereas the patients in Groups 2 and 4 received IV saline of the same volume. Anesthesia was maintained with sevoflurane. The recovery characteristics and EA in recovery room were assessed. RESULTS: The incidence of EA was significantly higher in Groups 2 and 4 and there was no difference between Groups 2 and 4. Group 2 had almost an eleven-fold higher risk of developing EA than did Group 1, and the incidence of EA in Group 4 was sixty-nine-fold higher than that of Group 1. The risk factor for EA was only the kind of medication. Preoperative anxiety had no significant correlation with EA. CONCLUSIONS: The incidence of EA after sevoflurane anesthesia is similar between ketamine and thiopental sodium anesthetic induction in children undergoing pediatric ophthalmic surgery. Also, the addition of a small dose of fentanyl after anesthetic induction decreases the incidence of EA.