Electrophysiologic neuromonitoring during repair of the thoracoabdominal aorta by anesthesiologists

Surgical repair of the thoracoabdominal aorta is associated with risk of spinal ischemia. Electrophysiologic neuromonitoring reduces this risk, but is usually performed by neurophysiologists not always available. In this study repair of the thoracoabdominal aorta monitored by anesthesiologists has been investigated.

Somatosensory and transcranial electrical motor evoked potentials were monitored in 20 patients. A lumbar intraspinal fluid drainage was inserted. Dacron graft replacement of the aorta was performed by sequentially clamping during partial cardiopulmonary bypass. Loss or decrease of amplitudes of evoked potentials of more than 50% prompted reinsertion of spinal arteries in the graft.

One patient not monitored with motor evoked potentials due to indwelling cardiac pacemaker had postoperative paraplegia. Somatosensory and motor evoked potentials were recordable in all other patients. Two patients died during surgery, one patient died postoperatively. No surviving patient monitored with somatosensory and motor evoked potentials had neurologic deficits.

Electrophysiologic neuromonitoring during surgical repair of the descending aorta can be successfully provided by anesthesiologists and should be predominately encouraged where neurophysiologists are not available due to organizational or financial shortcomings.