The effect of ketamine versus fentanyl on the incidence of emergence agitation after sevoflurane anesthesia in pediatric patients undergoing tonsillectomy with or without adenoidectomy

BACKGROUND: Emergence agitation (EA) has been documented as a common side-effect of sevoflurane anesthesia. This prospective, randomized, double-blind, placebo-controlled study was designed to compare the effects of ketamine versus fentanyl, administered 10 min before the end of surgery on the development of EA. METHODS: A total of 120 children aged 3-7 years of American Society of Anesthesiologists I-II physical status were randomly assigned to one of three equal groups receiving either ketamine 0.5 mg/kg (Group K), fentanyl 1 μg/kg (Group F) or saline (Group C) at 10 min before the end of surgery. Post-operative EA was assessed with Aono's four point scale. Recovery times, the post-operative pain and adverse reactions were assessed. RESULTS: There was no significant difference between the three groups regarding recovery and discharge times from post-anesthesia care unit. The incidence of EA was significantly low in Group K and Group F (15% and 17.5%, respectively) compared to the control group (42.5%), with no significant difference between Group K and Group F. There were no significant differences in Children's Hospital of Eastern Ontario Pain Scale between the three groups. The incidence of nausea or vomiting was significantly more in Group F compared to that in other two groups. However, no complications such as somnolence, oxygen desaturation or respiratory depression occurred during the study period and there were no episodes of hallucinations or bad dreams in the ketamine group. CONCLUSION: The intravenous administration of either ketamine 0.5 mg/kg or fentanyl 1 μg/kg before the end of surgery in sevoflurane-anesthetized children undergoing tonsillectomy with or without adenoidectomy reduces the incidence of post-operative agitation without delaying emergence.