The Use of Methadone and Ketamine for Intraoperative Pain Management in Cardiac Surgery: A Retrospective Cohort Study.
Journal of cardiothoracic and vascular anesthesia – February 01, 2025
Source: PubMed
Summary
Combining ketamine with methadone during cardiac surgery delayed patients' need for additional pain medication by over 2 hours compared to using methadone alone. This innovative pain management approach helped reduce opioid use on the first day after surgery. The study tracked over 6,800 cardiac surgery patients, comparing those who received both medications to those who got only methadone. While initial results were promising, pain levels remained similar between groups after day one.
Abstract
To evaluate whether the addition of ketamine to intraoperative methadone is associated with superior postoperative pain management and decreased opioid consumption compared with methadone alone in cardiac surgery patients. A retrospective cohort study. A large academic medical system comprising four sites. A total of 6,856 patients who underwent cardiac surgery with cardiopulmonary bypass and received intraoperative methadone between 2018 and 2023 were included. Patients were divided into two groups: those who received both methadone and ketamine (Group M+K; n = 5,696) and those who received methadone alone (Group M; n = 1,160). Intraoperative administration of methadone with or without ketamine. Some patients also received additional opioids such as hydromorphone and fentanyl. The primary outcomes were daily total oral morphine equivalents (OMEs) until postoperative day (POD) 7 and the time to first postoperative opioid administration. The secondary outcome was daily postoperative pain scores until POD 7. Exploratory outcomes included delirium and intensive care unit length of stay. The median time to first postoperative opioid administration was longer in Group M+K (7.2 hours) compared with Group M (5.0 hours) (hazard ratio = 0.88, 95% confidence interval: [0.82, 0.95]). Total OMEs were significantly lower in Group M+K on POD 0 (ß = -2.24; 95% confidence interval: [-3.2, -1.3]), with no significant differences beyond POD 0. No significant differences were found in pain scores or exploratory outcomes. Adding ketamine to methadone prolonged the time to first opioid consumption postoperatively but showed no benefits beyond POD 0. Future studies should consider protocolized dosing to optimize pain control.