Dosing of Methadone for Spine Surgery

Patients with spine surgery experience a significant amount of pain that can interfere with healing, rehabilitation and contribute to morbidity in the post-operative period. This study will compare post-operative opioid requirement at 24 and 48 hours to determine if methadone given in small aliquots until respiratory depression can act as a self-control to determine the correct dose required.

Subjects will be randomly assigned to one of two different protocols by a designated study team member based on a computer generated randomization table. Randomization will occur on the day of surgery. Randomization will be 1:1.

Post-operative data will be collected by blinded staff. Patient daily pain based on the analog scale of 0-10 post-operative for the first 72 hours, total opioid usage, length of stay, time to get out of bed.

Receive 0.2 mg/kg based on ideal body weight of methadone after the intubation and before positioning.

Receive incremental aliquots of methadone up to 0.5 mg/Kg based on ideal body weight titrated to apnea. Each subject will receive a 5-10 mg loading dose then aliquots of 5mg each, given at 3 to 5 minute time intervals. The practitioner will continue to coach patient to take deep breaths. After reaching the apnea threshold as determined by respiratory rate less than 8 breaths/min, induction of general anesthesia and intubation will proceed.

Subject will receive 0.2 mg/kg based on ideal body weight of methadone after the intubation and before positioning.

Subjects will receive incremental aliquots of methadone up to 0.5 mg/Kg based on ideal body weight titrated to apnea. Each subject will receive a 5-10 mg loading dose then aliquots of 5mg each, given at 3 to 5 minute time intervals.

Titrating methadone to respiratory depression allows the patient to act as his own control determining the dose he will require, improving pain control and consequently decreasing side effects and complications.

Inclusion Criteria: Patients must consent to participate and sign the IRB-approved informed consent prior to beginning any study specific procedures. At or between the ages 18 to 75 years. Undergoing multilevel thoracic, thoracolumbar and/or lumbar spine surgery with instrumentation and fusion. Exclusion Criteria: Methadone or buprenorphine use. Morbid obesity with BMI>40 Kg/m2. Chronic renal failure with creatinine>2.0 mg/dL. Liver failure as determined by cirrhosis or history of fulminant hepatic failure. Current or historical alcohol abuse. Current or historical drug abuse. Patients with history of prolonged QTc, as defined as a QTc value >450 ms in males and >460 ms in females. Patients with ASA status IV or V. Surgical diagnosis including spine tumor, infection, or trauma. In the Principal Investigator's opinion is not a candidate for the study. Unwilling to sign the informed consent form.

Gottschalk A, Durieux ME, Nemergut EC. Intraoperative methadone improves postoperative pain control in patients undergoing complex spine surgery. Anesth Analg. 2011 Jan;112(1):218-23. doi: 10.1213/ANE.0b013e3181d8a095. Epub 2010 Apr 24.