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

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.)