Comparison of spinal cord protection utilizing left atrial-femoral with femoral-femoral bypass in patients with traumatic rupture of the aortic isthmus.

Introduction: Postoperative paraplegia remains a dreaded complication of repair of traumatic rupture of the aortic isthmus. Claims have been made that left atrial-femoral bypass provides better spinal cord protection. To test the hypothesis that left atrial-femoral bypass is better than femoral vein-to-femoral artery bypass in regard to postoperative paraplegia, we concurrently compared the two techniques.
Methods: We compared the occurrence of paraplegia in 18 patients whose ruptures were repaired utilizing left atrial-femoral bypass with 10,000 units of systemic heparin (group A) and 72 patients with femoral-femoral bypass with heparin 300 units/kg and an oxygenator (group B) operated on between January 1995 and July 2004.
Results: The mortality rate was 5.6% (5/90), with no statistical difference between the two groups. Postoperative paraplegia was present in three (16.7%) group A patients and five group B (6.9%) patients. However, the specific etiology of the neurologic defect was not clear, as one patient's paraplegia was transient following a period of cardiac arrest, and four others had had neurologic injuries prior to the aortic repair. Median aortic cross-clamp times were shorter in group A (34 minutes vs. 49 minutes). No patient required reexploration for bleeding, and no patient developed a graft infection.
Conclusions: Paraplegia rates were higher in the left atrial-femoral group, but the difference was not statistically significant. This occurred despite the decreased cross-clamp times in this group. In patients undergoing repair of traumatic rupture of the aortic isthmus, left atrial-femoral bypass does not provide better spinal cord protection than femoral-femoral bypass.