Understanding How Methadone Treatment During Surgery Affects Pain Levels and the Need for Pain Medications After Surgery

Modulation of Post-operative Opioid Consumption and Pain by Intraoperative Methadone for Cancer Related Spinal Surgery - An Investigator Initiated Trial (IIT), Cluster Randomization Trial

The researchers are doing this study to find out whether giving methadone during spinal surgery helps manage pain in the first 72 hours after surgery better than other standard pain medications. Participants' pain will be measured by how much pain is reported after surgery, and how much additional pain medication is needed to lower pain levels. The researchers will look at whether giving methadone during surgery reduces the need for other pain medications after surgery. In addition, the team will compare the effects of the two standard treatments- one with methadone and one without methadone to to evaluate which one works best.

Inclusion Criteria:

• Adult patients (between 18-75 years of age) scheduled for extradural spine surgery with instrumentation (greater than or equal to two levels and including minimally invasive) of expected duration ≥ 2 hours
• Postoperative hospital stay expected to be ≥ 2 nights at the time of consent

Exclusion Criteria:

• Use of methadone currently or within the previous 6 weeks
• Drug misuse history (e.g., ketamine, cocaine, heroin, amphetamine, methamphetamine, MDMA, phencyclidine, lysergic acid, mescaline, psilocybin).
• Current use of opioid antagonist/partial antagonist (i.e. buprenorphine).
• Current or past diagnosis of a Major Psychiatric disorder (such as Schizophrenia, dementia, delirium).
• Patients with a BMI ≥ 36 kg/m2
• 2nd or 3rd degree heart block as assessed by preoperative EKG.
• QTc > 450 msec on preoperative EKG.
• Documentation of congestive heart failure and/or ejection fraction < 30% if recorded in the Pre-Operative Record.
• Contraindication to use of any analgesic medications listed in the ERAS pathways (acetaminophen, gabapentin, celecoxib, IV opioids).
• Any known hypersensitivity to methadone.
• Pregnant or breastfeeding.
• Abnormal liver function tests as related to the MSK guidelines for use of IV acetaminophen: ALT greater than 2 x Upper Limit of Normal (> 75 U/L)
• Serum Creatinine > 1.5 mg/dl
• Instrumented spine cases of less than 2 levels
• All non-instrumented spine cases
• All intradural tumor resections
• All "take backs" that occur within 72 hours of surgery (wound revisions, hematomas, etc.)