RESUMO
In the repair of aneurysms of the descending thoracic aorta, interruption of aortic flow has usually been accomplished by cardiopulmonary bypass, which has been associated with excessive bleeding due to the systemic heparinization required. To avoid this problem, the authors have used an external (Gott aneurysm) shunt, which does not require systemic heparinization. In 50 patients with an aneurysm of the descending thoracic aorta a Gott aneurysm shunt was used as an external bypass. The shunt is a flexible, transparent, polyvinyl chloride tube and its heparin-coated wall prevents clotting. Forty-two (84%) patients survived the operation. Thirty-two patients had surgical repair of a traumatic rupture of the descending aorta; 29 (91%) survived. Of 18 patients operated on for an arteriosclerotic aneurysm or a DeBakey type III dissection 13 (72%) survived. Most of the deaths occurred early in the series; among the last 14 patients treated for an arteriosclerotic aneurysm or dissection 13 (93%) survived. Paraplegia occurred once (2%) because a shunt was accidentally introduced outside the lumen of the descending aorta and therefore did not function. Another patient with an acutely transected aorta and bleeding had rapid cross-clamping of the aorta without a shunt but suffered a cardiac arrest due to postclamping acidosis. He was successfully resuscitated. No heart failure, paraplegia or renal failure occurred in the 48 patients properly protected with the Gott aneurysm shunt. Regardless of their etiology, thoracic aneurysms are unpredictable and the authors recommend surgical treatment in most patients, using this external bypass technique as a method of organ protection.
