Ketamine as a Major Component of an Anesthetic Plan for Spinal Cord Monitoring

Since our initial experience with spinal cord monitoring (SCM), we have searched for an anesthetic plan which would provide optimal conditions for the recording of somatosensory cortical evoked potentials (SSCEPs) during surgery involving the spine and/or spinal cord. As reported in a preliminary way at the Third International Symposium on Spinal Cord Monitoring [5], when faced with small baseline signals, we have (intraoperatively) switched from our “usual/best” anesthetic plan (50% N2O + Fentanyl infusion + Thiopental infusion/or 0.2% Forane) [4] to a plan whereby ketamine is substituted for N2O, leaving the other drugs the same. We have now expanded our series of ketamine cases to 33 and will summarize our data on 29 of the most complete cases done in a period from 1985 to April 1989.