The Effect of Alfentanil on Emergence Delirium Following General Anesthesia in Children: A Randomized Clinical Trial

Background Emergence delirium can occur after general anesthesia in children. An intravenous infusion of alfentanil may reduce the incidence or severity of emergence delirium after sevoflurane anesthesia. Objective The study aimed to investigate the effects of alfentanil intravenous infusion on emergence delirium and other perioperative complications. Method This was a single-center, randomized, placebo-controlled, double-blind clinical trial. A total of 172 children undergoing ambulatory dental treatment were randomized into three groups. Alfentanil group Alf2 received 0.2 mu g/kg/min of alfentanil for continuous infusion, alfentanil group Alf4 received 0.4 mu g/kg/min alfentanil, and the saline group (group Sal) received a continuous infusion of normal saline, with the same volume as the two other groups, as a placebo. The incidence of emergence delirium (assessed by the Paediatric Anaesthesia Emergence Delirium [PAED] scale), hemodynamic parameters, and recovery characteristics were recorded during the recovery period. The Aono scale was also used to assess for emergence delirium. A WeChat applet was designed to facilitate a caregiver teleconsultation and to provide feedback on postoperative nausea and vomiting and any other complications after discharge. Results The incidence of emergence delirium in group Alf2 (22.9%) and group Alf4 (21.1%) was significantly lower than that observed in the Sal group (48.3%). The PAED scores in group Alf2 (6.4 +/- 3.5) and group Alf4 (5.8 +/- 3.8) were significantly lower than those for group Sal (9.6 +/- 5.1) (p < 0.01). Ten children in the Alf4 group needed manual ventilatory assistance to maintain end-tidal carbon dioxide (ETCO2) < 55 mm; children in group Alf2 did not. There was no significant difference between the discharge time of groups Alf2 and Sal (31.2 +/- 4.64 vs 30.5 +/- 2.82 min; 0.659 [95% confidence interval {CI} -1.052 to 2.369], p = 0.643); the time to discharge of group Alf4 (35.16 +/- 3.97 min) was significantly longer than that of groups Alf2 and Sal (p < 0.01). The incidence of nausea and vomiting was similar in the three groups. No other clinically relevant adverse events were observed. Conclusions Intravenous infusion of 0.2 mu g/kg/min and 0.4 mu g/kg/min alfentanil decreased the incidence of emergence delirium in the post-anesthesia care unit. The 0.2 mu g/kg/min dose of alfentanil resulted in less respiratory depression and discharge delay than the 0.4 mu g/kg/min alfentanil dose.