Operation for an infected thoracoabdominal aneurysm in a patient previously treated with an axillobifemoral bypass for an infected abdominal aortic prosthesis: a case report.

High operative mortality of infected thoracoabdominal aortic aneurysms (ITAA) is partly attributable to ischemic injury during aortic clamping. A case is presented of an 88-year old man who was admitted with imminent rupture of an ITAA. Axillobifemoral bypass grafting had been performed after removal of an infected abdominal aortic prosthesis six years earlier. In situ graft replacement was performed during 70 minutes of aortic clamping just below the pulmonary hilum without causing any but transient renal ischemic injury. Since the infrarenal aorta was absent after previous removal of an infected aortic prosthesis, the axillobifemoral bypass provided sufficient blood supply to intestines, kidneys and spinal medulla via arterial collaterals. Blood supply was sufficient, although a previous rectosigmoid resection must have destroyed some of the collaterals and one iliac artery was chronically occluded. The most important message from this case is that an axillobifemoral bypass may prevent ischemic injury during operations for ITAA even when collateral circulation is reduced, possibly on the condition that backbleeding from end-organ arteries is prevented, and there is a pressurized aortic segment that can redistribute blood that arrives via arterial collaterals.