Methadone and ketamine combo effective for pain control after spinal surgery: Study
USA: Perioperative administration of a combination of methadone and ketamine improves postoperative analgesia and reduces opioid need in patients who have undergone spine surgery, finds a recent study in the journal Anesthesiology. The combo could be considered in patients recovering from spine surgery.
Patients undergoing spinal fusion surgery frequently report severe postoperative pain despite application of multimodal pain management strategies. Methadone and ketamine, N-methyl-d-aspartate receptor antagonists, have been shown to facilitate postoperative pain control. The study by Glenn S. Murphy, Northwestern University Feinberg School of Medicine, Chicago, Illinois, and colleagues, therefore, tested the primary hypothesis that patients recovering from spinal fusion surgery who are given ketamine and methadone use less hydromorphone on the first postoperative day than those give methadone alone.
For this purpose, the researchers conducted a randomized, double-blind, placebo-controlled trial that included 130 spinal surgery patients. They were randomized to receive either methadone at 0.2 mg/kg (ideal body weight) intraoperatively and a 5% dextrose in water infusion for 48 h postoperatively (methadone group) or 0.2 mg/kg methadone intraoperatively and a ketamine infusion (0.3 mg · kg−1 · h−1 infusion [no bolus] intraoperatively and then 0.1 mg · kg−1 · h−1 for next 48 h [both medications dosed at ideal body weight]; methadone/ketamine group).
Anesthetic care was standardized in all patients. The primary outcome was intravenous hydromorphone use on postoperative day 1. Pain scores, intravenous and oral opioid requirements, and patient satisfaction with pain management were assessed for the first 3 postoperative days.
Key findings of the study include:
- Median (interquartile range) intravenous hydromorphone requirements were lower in the methadone/ketamine group on postoperative day 1 (2.0 vs. 4.6 mg in the methadone group, median difference 2.5 mg) and postoperative day 2.
- In addition, fewer oral opioid tablets were needed in the methadone/ketamine group on postoperative day 1 (2 vs. 4 in the methadone group) and postoperative day 3.
- Pain scores at rest, with coughing, and with movement were lower in the methadone/ketamine group at 23 of the 24 assessment times.
- Patient-reported satisfaction scores were high in both study groups.
"Postoperative analgesia was enhanced by the combination of methadone and ketamine, which act on both N-methyl-d-aspartate and μ-opioid receptors," wrote the authors. "The combination could be considered in patients having spine surgery."
The study titled, "Perioperative Methadone and Ketamine for Postoperative Pain Control in Spinal Surgical Patients: A Randomized, Double-blind, Placebo-controlled Trial," is published in the journal Anesthesiology.