Safety profile of intraoperative methadone for analgesia after major spine surgery: An observational study of 1,478 patients. Categories: Multimodal Analgesia in Spine Surgery Author: Alpert SB, Dunn LK, Durieux ME, Fang S, Hanak MF, Leibowitz MK, Naik BI, Nemergut EC, Tsang S, Yerra S