Methadone versus morphine for postoperative pain in patients undergoing surgery for gynecological cancer: A randomized controlled clinical trial

The aim of this study was to compare methadone and morphine for the management of postoperative. Open, controlled study. Postoperative recovering area, ward. Sixty-four patients, ASA I-III, undergoing gynecological surgery for cancer. Morphine or methadone 0.15 mg/kg given preoperatively. After operation an intravenous morphine or intravenous methadone infusion at doses of 12 mg/day was started. Pain intensity and opioid consumption. Methadone infusion provided a better analgesia in comparison with morphine infusion on the second day. Opioid consumption was significantly lower in the methadone group. No episodes of relevant desaturation or signs of respiratory depression were recorded. A preoperative bolus of methadone, followed by a continuous infusion of low doses post-operatively, provided a better analgesia, without adding risk of adverse effects, in comparison with morphine. •A preoperative bolus of methadone, followed post-operatively by a continuous infusion of low doses provided a potent and better analgesia than morphine in gynecological surgery.•The risks of adverse effects with methadone was similar to those produced by morphine.•Methadone could be a relevant resource for postoperative pain.