Methadone vs desflurane as an adjunct to remifentanil may help reduce perioperative opioid requirements in adolescents undergoing spinal surgery, according to a study published in the Journal of Anesthesia.
The study included 60 adolescents scheduled to undergo posterior spinal fusion to treat idiopathic scoliosis. Participants were randomly assigned to receive desflurane plus remifentanil, remifentanil plus methadone (0.1 mg/kg intravenously over 15 minutes), or remifentanil plus magnesium (50 mg/kg bolus over 30 minutes followed by 10 mg/kg/hour). The primary outcomes were opioid requirements and postoperative pain scores, and secondary outcomes included intraoperative anesthetic requirements, neurophysiologic monitoring conditions, and emergence times.
Patients receiving desflurane plus remifentanil had a total opioid requirement of 34±0.11 mg/kg compared with 0.26 ± 0.10 mg/kg for participants administered remifentanil plus methadone (95% CI, of difference: −0.14, −0.01; P =.035). This difference in opioid requirements was attributed to intraoperative dosing (0.04±0.02 mg/kg in the desflurane plus remifentanil group vs 0.02±0.01 mg/kg in the remifentanil plus methadone group; 95% CI of difference: −0.01, −0.02; P =.003). Pain scores were comparable when methadone vs desflurane was used as an adjunct to remifentanil, and the use of magnesium vs desflurane did not have an effect on opioid requirements or pain scores.
“Given the potential for hyperalgesia with the intraoperative use of remifentanil, the adjunctive use of methadone may be warranted in this patient population,” the researchers wrote.
Martin DP, Samora WP III, Beebe AC, et al. Analgesic effects of methadone and magnesium following posterior spinal fusion for idiopathic scoliosis in adolescents: a randomized controlled trial [published online August 4, 2018]. J Anesth. doi:10.1007/s00540-018-2541-5