BACKGROUND: During anesthesia in children sometimes we are confronted with airway obstruction, due to for example laryngospasm or stridor just after tracheal extubation. The use of intravenous lidocaine to prevent laryngospasm or stridor is controversial. This study was undertaken to investigate the effect of intravenous lidocaine on the prevention of laryngospasm or stridor by checking oxygen saturation using a pulse oximeter. METHODS: Sixty children undergoing strabismus surgery with general anesthesia (N2O-O2-enflurane) were divided into two groups, the L group (n = 32) received intravenous lidocaine 1 mg/kg, and the S group (n = 28) received the same amount of saline, both 5 minutes before extubation. The maximal and minimal levels of oxygen saturation were checked in the operation room and in the post anesthetic recovery room (PAR) after tracheal extubation. The numbers of patients with have oxygen saturation of less than 95% were counted in each group. Respiratory depression and sedation scores were noted at PAR in both groups. RESULTS: The number of cases that experienced laryngospasm or stridor was 4 (12.5%) in the L group and 3 (10.7%) in the S group, showing no significant difference. No respiratory depression was observed in either group and no difference in the sedation scores 5, 15, 30 minutes after arrival at PAR was observed between two groups. CONCLUSIONS: The intravenous administration of lidocaine 1 mg/kg 5 minutes before extubation in strabismus surgery did not prevent laryngospasm or stridor.