Assessment of risk factors for spinal cord ischaemia in surgery of thoracoabdominal aneurysms without use of adjuncts.

Between January 1983 and June 1986, 61 patients underwent resection of a thoracoabdominal aneurysm (TAA) by means of simple cross-clamping without the use of adjuncts. All patients survived the operation. Mortality was 6.5% at 30 days and 16.4% at 1 year. Spinal cord injury occurred in 8 patients. Three patients sustained paraplegia and 5 patients recovered from paraparesis within 6 months. In univariate analysis, risk factors were the presence of symptoms (P less than or equal to 0.01) and emergency operation (P less than or equal to 0.03). Spinal cross-clamptime (ACX), aetiology and the number of open intercostal arteries (ICA) did not appear to be single denominators for spinal cord injury. Testing clusters of variable related to spinal cord injury revealed an increased risk for the group of patients (n = 20) with type I (most of the thoracic and the upper abdominal aorta) and type III (the distal half of the thoracic and varying segments of the abdominal aorta) aneurysms, when the number of ICA was greater than or equal to 4 or less than or equal to 1, with a spinal ACX of greater than or equal to 35 min, and in the presence of symptoms and previous dissection (P = 0.001). In patients (n = 19) with type II aneurysm (involving most of the thoracic and most of the abdominal aorta) an increased risk was present when the number of open ICA was greater than or equal to 4, with a spinal ACX of greater than or equal to 35 min and in the presence of symptoms (P = 0.01). Spinal cord injury was confined to these types of TAA (P less than or equal to 0.001) and paraplegia occurred only in type I and III aneurysms.