Impact of anesthesia on transcranial electric motor evoked potential monitoring during spine surgery: a review of the literature.
OBJECTIVE
Transcranial motor evoked potential (TcMEP) monitoring is frequently used in complex spinal surgeries to prevent neurological injury. Anesthesia, however, can significantly affect the reliability of TcMEP monitoring. Understanding the impact of various anesthetic agents on neurophysiological monitoring is therefore essential.


METHODS
A literature search of the National Library of Medicine database was conducted to identify articles pertaining to anesthesia and TcMEP monitoring during spine surgery. Twenty studies were selected and reviewed.


RESULTS
Inhalational anesthetics and neuromuscular blockade have been shown to limit the ability of TcMEP monitoring to detect significant changes. Hypothermia can also negatively affect monitoring. Opioids, however, have little influence on TcMEPs. Total intravenous anesthesia regimens can minimize the need for inhalational anesthetics.


CONCLUSIONS
In general, selecting the appropriate anesthetic regimen with maintenance of a stable concentration of inhalational or intravenous anesthetics optimizes TcMEP monitoring.
Department of Neurosurgery, University of Michigan Health System, Ann Arbor, Michigan 48109-5338, USA.
Anthony C
AC
Wang
Khoi D
KD
Than
Arnold B
AB
Etame
Frank
F
La Marca
Paul
P
Park
D000758:Anesthesia / Q000009:adverse effects / Q000379:methods*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000009:adverse effects; D004558:Electric Stimulation / Q000379:methods; D019054:Evoked Potentials, Motor / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008523:MEDLARS / Q000706:statistics & numerical data; D016343:Monitoring, Intraoperative / Q000379:methods*; D019148:Neuromuscular Blockade / Q000009:adverse effects / Q000379:methods; D009482:Neurophysiology / Q000706:statistics & numerical data; D019637:Orthopedic Procedures / Q000379:methods; D013119:Spinal Cord Injuries / Q000517:prevention & control; D013131:Spine / Q000601:surgery*
D018685:Anesthetics, Inhalation