Effect of Ketamine on Intraoperative Motor Evoked Potentials During Adult Thoracolumbar Spinal Fusion Surgery

What this Trial Is About

This research aims to understand how ketamine affects intraoperative motor evoked potentials (MEPs) in adult patients undergoing thoracolumbar spinal fusion surgeries. Spinal surgeries often use MEP monitoring to ensure the spinal cord's function is preserved during the procedure. Since ketamine is commonly used as an anesthetic adjunct to reduce pain and opioid use during these surgeries, the study evaluates its impact on this important safety monitoring technique. Participants will receive a standardized general anesthetic along with increasing doses of ketamine administered in three steps: a 0.1 mg/kg bolus followed by infusion at 3 mcg/kg/min, then a 0.3 mg/kg bolus with infusion at 15 mcg/kg/min, and finally a 0.85 mg/kg bolus with infusion at 50 mcg/kg/min. Motor evoked potentials will be recorded multiple times after each dosing step, and blood samples will be taken to measure ketamine plasma levels. After these assessments, the surgery will continue per usual care. During the procedure, participants will have neuromonitoring equipment placed as part of standard care to collect baseline and post-ketamine MEP data. Researchers will collect demographic and medical information from patient records. The primary measures include changes in threshold and supramaximal MEPs and MEP facilitation within 30 minutes of ketamine administration. The study will monitor safety and ketamine blood levels, with total participation lasting through the surgical procedure.

Effect of Ketamine on Intraoperative Motor Evoked Potentials