Spinal cord ischemia following operations on the abdominal aorta.

Spinal cord ischemia following operations on the abdominal aorta is considered an unpredictable event attributable to variations in spinal cord blood supply. Our experience with seven cases of spinal cord ischemia contradicts this hypothesis. All patients had a bifurcation graft implanted. Three patients had bilateral interruption of hypogastric circulation. Each had gluteal necrosis and two had left colon ischemia. Two patients had unilateral hypogastric ligation. In both of these patients, early postoperative hypotension preceded recognition of spinal cord ischemia. Two patients without known interruption of hypogastric flow had proximal side-to-end anastomoses placed in an atheromatous aorta. Intraoperative peripheral emboli occurred in one and postoperative visceral emboli occurred in the other patient. In the latter case spinal cord ischemia occurred late concomitantly with embolization. The surmised important details in patients' courses with spinal cord ischemia are (1) interference with pelvic blood flow (five of seven patients) severe enough in three cases to cause gluteal necrosis and (2) a high incidence of perioperative complications. Interruption of an anomalous spinal artery was probably not a factor as cord lesions were mostly distal and no case of spinal cord ischemia occurred after a cylinder graft was placed. Spinal cord ischemia is potentially preventable. Our experience reemphasizes the importance of hypogastric perfusion, the dangers of handling the atheromatous aorta, and the necessity for avoiding postoperative hypotension.