Intraoperative administration of methadone reduced postoperative pain and opioid consumption following cadaveric renal transplantation: a randomized controlled trial

Abstract

Objective: In this randomized clinical trial study, the impact of prophylactic administration of methadone during surgery on postoperative pain and analgesic requirement following cadaveric renal transplantation was assessed.
 Methods: Ninety patients were randomized to receive either methadone 0.15 mg/kg or 0.15mg/kg morphine after tracheal intubation. Both groups were treated with acetaminophen 1 gr before extubation. Protocol of anesthesia was the same in both groups and the anesthetist was blinded to the study groups. The primary outcome was defined as total opioid consumption during recovery and first day after surgery. Secondary outcomes were pain scores and level of patients’ sedation during the recovery period and first postoperative day as well as opioid-related complications.
 Results: Data of eighty-five eligible patients were analyzed. The mean pain and sedation scores were lower in the methadone group compared to the morphine group during recovery and the first 24 hours after surgery. The time of first rescue analgesic requirement was later in the methadone group (10.4 vs 6.3 hours). Also, postoperative morphine consumption was significantly less in the methadone group compared to patients receiving morphine (3.5 vs. 6.9 mg; P < 0.001).
 Conclusion: Intraoperative administration of methadone decreased postoperative pain scores, reduced opioid consumption after surgery and improved level of sedation during the first 24 hours after surgery.