Background: Inhalation anesthesia with sevoflurane is widely used for pediatric patients. However, emergence agitation after sevoflurane anesthesia has been reported. This study examined whether or not a lidocaine injection into subtenons space and/or preoperative anxiety affects emergence agitation after pediatric strabismus surgery with sevoflurane anesthesia.

METHODS: Two hundred children receiving sevoflurane anesthesia for strabismus surgery were randomly assigned into four groups. Before induction, the anesthesiologist explained the general anesthesia and its possible complications to the children in groups 2 and 4, while it did not in groups 1 and 3. The anxiety score was then evaluated. Anesthesia was induced with 4-6 mg/kg thiopental sodium and 0.8 mg/kg rocuronium, and was maintained with O2-N2O-sevoflurane. Before the end of surgery, a surgeon injected the subtenons space with 2% lidocaine 1 ml in groups 3 and 4, while there was no injection in groups 1 and 2. The degree of emergence agitation was assessed at the postanesthetic care unit using a five point scoring scale.

Results: The preoperative anxiety score was similar in the preoperative explanation (Gp 2, 4) and non preoperative explanation groups (Gp 1, 3). The incidence of emergence agitation was significantly higher in patients with a higher preoperative anxiety score (P < 0.05). The incidence of emergence agitation was 17% in the subtenons lidocaine injection group, which was significantly lower than in the control group (36%) (P < 0.05).

CONCLUSIONS: A lidocaine injection into the subtenons space reduces emergence agitation after sevoflurane anesthesia in pediatric strabismus surgery.