Abstract
Intraoperative monitoring of motor evoked potential (MEP) has been conducted to prevent postoperative motor deficits in patients undergoing craniotomy for cerebral aneurysm and brain tumor, spine/spinal surgery and thoracoabdominal aortic aneurysm surgery. During craniotomy, selection of transcranial or direct cortical electrical stimulation and intensity of stimuli are important determinants for successful MEP monitoring. During spine/spinal surgery, MEP recording may be occasionally difficult in patients with preoperative motor dysfunction or scoliosis, so techniques to augment MEP amplitude such as post-tetanic MEP may be applied. During thoracoabdominal aortic aneurysm surgery, careful anesthetic management is essential, because the induction of hypothermia and cardiopulmonary bypass with aortic clamping can markedly affect MEP responses. Proper interpretation of intraoperative MEP changes during thoracoabdominal aortic aneurysm surgery is crucial. We describe the methodology and pitfalls of MEP monitoring and anesthetic management during MEP monitoring.
