REDUCTION OF NEUROLOGIC INJURY AFTER HIGH-RISK THORACOABDOMINAL AORTIC OPERATION

Background. Of all aortic operations, thoracoabdominal aortic repairs have the highest risk of spinal cord neurologic injury, manifest by lo wer limb paraplegia or paraparesis. Cerebrospinal fluid drainage combi ned with intrathecal papaverine (CSFDr + IP) may reduce the risk and s everity of neurologic injury. The objective of this study was to evalu ate the effect of CSFDr + IP to prevent neurologic injury after high-r isk thoracoabdominal aneurysm repairs. Methods. We screened 64 patient s before operation with descending thoracic or thoracoabdominal aneury sms for possible inclusion in a prospective, randomized study. Thirty- three patients with high-risk type I and II thoracoabdominal aneurysms met inclusion criteria and 17 were randomly assigned to CSFDr + IP an d 16 to the control group. The study was terminated early after interi m analysis revealed a significant difference. Results, Of 64 patients screened, 2 patients died after operation (3.1%, 2/64); both were in t he randomized study (6%, 2/33), and neither had a neurologic injury. N eurologic injury developed in 2 CSFDr + IP patients and 7 control pati ents (p = 0.0392). Control patients also had lower postoperative motor strength scores (p = 0.0340). On multivariate analysis, risk factors for neurologic injury included (p < 0.05) longer cross-clamp time, fai lure to actively cool with bypass, and postoperative hypotension, wher eas CSFDr + IP was protective. Logistic regression showed that CSFDr IP and active cooling significantly reduced the risk of injury and th at the two combined modalities were additive. Of 64 patients screened, only 2 (3%) had a permanent neurologic deficit preventing ambulation. Conclusions. For high-risk thoracoabdominal aneurysms, CSFDr + IP was effective in reducing the incidence and severity of neurologic injury . Active cooling may be further additive to CSFDr + IP protection, alt hough this needs to be confirmed in a larger study. (Ann Thorac Surg 1 998;66:132-5) (C) 1998 by The Society of Thoracic Surgeons.