In an attempt to prevent paraplegia, a devastating complication common after the repair of traumatic rupture of the aorta, we have used partial cardiopulmonary bypass. Most of the patients in our series (79.5%) underwent other major surgical procedures immediately before or after the aortic repair. Eight of the 110 patients died before aortic repair could be performed. The aorta was not repaired in 3, because of other injuries. In 9, the repair was done without a shunt or bypass; 4 patients died and 2 (22.2%) survived without paraplegia. One of the 2 who underwent repair with a Gott shunt died; the survivor suffered no cord damage. Of the 88 patients whose repair was carried out under cardiopulmonary bypass, 6 died and 80 (90.9%) survived without paraplegia. None of the last 39 patients has become paraplegic, as vasodilator treatment is now discontinued during the cross-clamp period. Serious intracranial injury was present in 19 patients; in 3 (15.8%) the injury became worse after repair. There was no evidence of new or increased intraabdominal bleeding during heparinization. Except in the event of pulmonary lacerations, systemic heparin therapy was not associated with major problems.