Intravenous methadone versus regional and neuraxial analgesic techniques in the peri-operative period: a scoping review.

There is a renewed interest in intravenous methadone as a long-acting peri-operative opioid. However, evidence comparing intravenous methadone with contemporary regional and neuraxial analgesic techniques remains unclear. This scoping review aimed to map the current evidence evaluating intravenous methadone against regional and neuraxial analgesic techniques in the peri-operative period. This review conformed to Preferred Reporting Items for Systematic Reviews and Meta-analyses (extension for Scoping Reviews) guidelines. Relevant articles were searched in Medline, Scopus, Web of Science, EMBASE and CENTRAL from January 2000 to May 2026. All studies were reviewed with no language restrictions. Four retrospective studies involving 1341 patients were included. Intravenous methadone was compared with intrathecal morphine, epidural analgesia and transversus abdominis plane blocks across cardiac, abdominal, thoracic, pancreatic and caesarean surgeries. Three studies reported higher postoperative pain scores among patients receiving intravenous methadone compared with neuraxial analgesia, although this did not translate to clinically significant differences in opioid consumption. Shorter vasopressor requirements and earlier mobilisation were reported in patients receiving intravenous methadone. Complications were inconsistently reported across studies. In conclusion, current evidence comparing intravenous methadone with regional and neuraxial analgesic techniques remains limited and highly heterogeneous. Although neuraxial techniques were associated with lower pain scores, this did not consistently translate into higher opioid consumption among patients receiving intravenous methadone. Prospective multicentre randomised controlled trials are required to better define the role of intravenous methadone within contemporary peri-operative analgesic pathways.