Intraoperative Methadone in Next-day Discharge Outpatient Surgery: A Randomized, Double-blinded, Dose-finding Pilot Study

Intraoperative Methadone in Spine Surgery ERAS Protocols: A Systematic Review of the Literature

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically review the use of intraoperative methadone in spine surgery and examine its effects on postoperative opioid use, pain, length of stay, and operative time.

SUMMARY OF BACKGROUND DATA

Spine surgery patients commonly have a history of chronic pain and opioid use, and as a result, they are at an increased risk of severe postoperative pain. While pure mu opioids remain the standard for acute surgical pain management, they are associated with significant short-term and long-term adverse events. Methadone presents an alternative to pure mu opioids which may improve postoperative management of pain following intraoperative use.

METHODS

A systematic review of MEDLINE, Embase, and Web of Science databases was conducted to review existing literature detailing operating time, postoperative pain, opioid usage, and hospital length of stay (LOS) following intraoperative methadone administration in spine surgery.

RESULTS

Following screening of 994 articles and application of inclusion criteria, 8 articles were included, 4 of which were retrospective. Conventional spine surgery intraoperative analgesic strategies used as comparators for intraoperative methadone included hydromorphone, ketamine, and sufentanil. Considering patient outcomes, included studies observed that patients treated with intraoperative methadone had statistically similar or significantly reduced pain scores, opioid usage, and LOS compared with comparator analgesics. However, one study observed that intraoperative methadone used in a multimodal analgesia regimen strategy with ketamine resulted in a shortened LOS compared with the use of intraoperative methadone alone. Differences in operating time between cases that used intraoperative methadone and cases that used comparator analgesics were not statistically significant among included studies.

CONCLUSION

Methadone may present an alternative option for both intraoperative and postoperative analgesia in spine surgery recovery protocols and may reduce postoperative pain, opioid use, and LOS while maintaining consistent operating time and reduced side effects of pure mu opioids.

LEVEL OF EVIDENCE

Level II.

Single-dose Intraoperative Methadone for Pain Management in Pediatric Tonsillectomy: A Randomized Double-blind Clinical Trial

BACKGROUND

More than 500,000 elective tonsillectomies are performed in U.S. children annually. Pain after pediatric tonsillectomy is common, often severe, and undertreated. There is no consensus on the optimal management of perioperative tonsillectomy pain. Methadone, with an elimination half-life of 1 to 2 days, has a longer duration of effect than short-duration opioids such as fentanyl. The primary objective of this study was to investigate the intraoperative use of methadone for pediatric tonsillectomy. It tested the hypothesis that methadone would result in less postoperative opioid use compared with short-duration opioids in children after tonsillectomy.

METHODS

This double-blind, randomized, parallel group trial in children (3 to 17 yr) undergoing tonsillectomy compared single-dose intravenous methadone (0.1 mg/kg then 0.15 mg/kg age-ideal body weight, in a dose escalation paradigm) versus as-needed short-duration opioid (fentanyl) controls. Opioid use, pain, and side effects were assessed in-hospital and 7 days postoperatively via electronic surveys. The primary outcome was total 7-day opioid use in oral morphine equivalents per kilogram (kg). Secondary outcomes were opioid use in the postanesthesia care unit, daily pain scores, and total number of 7-day opioid doses used.

RESULTS

Data analysis included 60 children (20/group), age 5.9 ± 3.7 yr (mean ± SD; median, 4; range, 3 to 17). Total 7-day opioid use (oral morphine equivalents per kg median [interquartile range]) was 1.5 [1.2, 2.1] in controls, 0.9 [0.1, 1.4] after methadone 0.1 mg/kg (P = 0.045), and 0.5 [0, 1.4] after methadone 0.15 mg/kg (P = 0.023). Postanesthesia care unit opioid use (oral morphine equivalents per kg) in controls was 0.15 [0.1, 0.3], 0.04 [0, 0.1] after methadone 0.1 mg/kg (P = 0.061). and 0.0 [0, 0.1] after methadone 0.15 mg/kg (P = 0.021). Postoperative pain scores were not different between groups. No serious opioid-related adverse events occurred.

CONCLUSIONS

This small initial study in children undergoing tonsillectomy found that single-dose intraoperative methadone at 0.15 mg/kg age ideal body weight was opioid-sparing compared with intermittent fentanyl.

EDITOR’S PERSPECTIVE