Heparinless partial cardiopulmonary bypass for the repair of aortic trauma

Objective: We hypothesized that partial cardiopulmonary bypass with a heparin-bonded system would be a technically simple, effective adjunct for reducing paraplegia during repair of traumatic aortic rupture. It avoids the risk of heparin, but, unlike left atrial-arterial bypass, it can heat, cool, oxygenate, and rapidly infuse volume if needed. Methods: A retrospective review was conducted of patients admitted for aortic trauma from July 1994 to December 1999. Bypass consisted of femoral venous (right atrial) cannulation, a centrifugal pump, and an oxygenator-heater/cooler. Arterial return was to the femoral artery or distal aorta. The entire system was heparin-bonded and no systemic heparin was given. Results: Heparin-bonded partial bypass was established in 50 patients (mean age 43 ± 17 years). Crossclamp time was 32 ± 11 minutes (range 14-70 minutes), mean flow 3.0 ± 0.8 L/min, and bypass time 64 ± 43 minutes. During repair, 58% of patients received volume through the system (mean 1.1 ± 1.9 L). Core temperature rose slightly (35.9°C ± 0.7°C to 36.3°C ± 0.8°C). Three of the 15 patients who underwent percutaneous femoral arterial and venous cannulation concomitant with their angiograms had vessel injury, with one limb loss, and this procedure was discontinued. Thirty-five patients underwent percutaneous femoral vein and direct distal aortic cannulation without event. The mortality rate for patients supported by bypass was 10%, and all deaths were due to other injuries. There were no new cases of paraplegia and no worsening of intracranial or pulmonary injuries. Conclusions: Heparin-bonded bypass is technically simple to use and avoids the risk of anticoagulation. Paraplegia was avoided. The ability to correct hypothermia, oxygenate, and rapidly infuse volume may simplify management and improve outcomes.