Methadone for Emergence Delirium in Ambulatory Pediatric Strabismus Surgery

Background: Emergence delirium in children following strabismus surgery is a distressing and potentially dangerous condition and is likely attributable to visual disturbances, pain, and anesthetic gases. We explored whether a single intraoperative dose of methadone could reduce emergence delirium. Methods: Our study was an institutional review board-approved prospective, controlled, before-and-after investigation. Inclusion criteria were age <18 years and American Society of Anesthesiologists (ASA) classification 1 or 2. Patients were excluded for obesity, documented sleep apnea, significant neurologic disease, or inpatient status. Control group patients were recruited sequentially, and the anesthetic was performed per preference. The study group was recruited similarly and received an intravenous dose of methadone 0.15 mg/kg at induction. The primary outcome was peak score on the Pediatric Anesthesia Emergence Delirium (PAED) scale. Secondary outcomes included time to anesthetic emergence, postoperative pain scores, postanesthesia care unit (PACU) length of stay, and postdischarge respiratory complications. Results: Forty-nine control group and 55 study group patients were recruited. No significant differences were found between groups for age, sex, weight, ASA classification, or duration of surgery. The control group received more preoperative midazolam, intraoperative fentanyl, and intraoperative ketorolac. Compared to the control group, the study group had 42% and 85% reductions in peak and severe PAED scale scores, respectively, in the PACU and required less rescue pain medications. Anesthetic emergence time and length of stay were not different between the groups. No significant postoperative complications occurred. Conclusion: Emergence delirium following outpatient pediatric strabismus surgery was substantially mitigated by the use of intraoperative methadone without affecting PACU throughput. No significant complications occurred. Further study is warranted to corroborate routine use of this drug for emergence delirium.