[Motor Evoked Potentials and Aortic Surgery]

Motor dysfunction following descending and thoracoabdominal aortic surgery including thoracic endovascular aortic repair remains as one of their devastating complications, although several interventions have tried to preserve spinal cord blood flow during and after aortic aneurysm surgery for the purpose of reducing the incidence of postoperative paraplegia. One of the main limitations of protective strategies is the inability to assess the adequacy of spinal cord perfusion and spinal cord function intraoperatively. Advances in stimulation technique using short train pulses could make intraoperative monitoring of functional integrity of motor pathways possible by recording myogenic motor evoked potentials (MEP), which is a highly sensitive technique to assess spinal cord integrity, identifying insufficient blood flow. To reduce the risk of neurologic injury, anesthesiologists are required to properly understand monitoring of MEP and to manage anesthesia and hemodynamics appropriately. Here, we summarize the strategies for spinal cord protection, including the functional monitoring of spinal cord and anesthetic techniques.