OBJECTIVETo evaluate the effect of aorta-iliac bypass total thoracoabdominal aorta aneurysm repair to spinal cord function.

METHODSThis was a prospective study. From June 2014 to April 2015, 31 patients underwent total thoracoabdominal aorta aneurysm repair were treated with aorta-iliac bypass technique. There were 23 male and 8 female patients with a mean age of (36±12) years. A 4-branched tetrafurcate graft was used. The aorta-iliac bypass was established, then distal descending aorta was perfused in a retrograde fashion via bypass graft. Thoracic and abdominal aorta were replaced in a staged fashion. Evoked potentials (EP) monitoring was adopted to assess the spinal cord ischemia throughout the procedure. The intraoperative evoked potentials results, clinical outcomes and follow-up results of this technique were evaluated.

RESULTSThe EP wave disappeared after proximal descending aorta clamped and gradually recovered after the patent segmental arteries reattached. Motor evoked potentials disappeared for (56±18) minutes, somatosensory evoked potentials disappeared for (50±19) minutes. The EP wave was restored to normal at the end of operation in all cases. The somatosensory evoked potentials remained unchanged in 2 cases (false negative). One case died after operation. There were acute kidney dysfunction in 3 cases, and pulmonary haemorrhage in 1 case. No spinal cord injure occurred. The median follow-up after operation was 8 months (ranging from 1 to 11 months). There was no delayed neurologic deficit or relative death.

CONCLUSIONSThere is a transient function loss of spinal cord during the aorta-iliac bypass total thoracoabdominal aorta aneurysm repair. But the process is reversible. The technique of the aorta-iliac bypass is practicable.