The objective of this trial is to determine whether an opioid-free general anesthetic (OFA) technique utilizing ketamine, dexmedetomidine, and lidocaine infusions can help reduce postoperative pain in opiate-dependent chronic pain patients (CPPs) undergoing spine surgery when compared with traditional opioid-containing techniques. It is expected that this OFA regimen will have a measurable reduction on postoperative opioid consumption and pain scores in CPPs.

Inclusion Criteria:

• Chronic pain > 6 months, opiate-using patients scheduled for thoracic or lumbar spinal surgery

Exclusion Criteria:

• Pregnant or breastfeeding women, significant hepatic, renal or cardiac disease, allergy to any of the study drugs, inability to consent, respond to pain assessments or use the patient controlled analgesia device