RENAL-FAILURE AFTER THORACOABDOMINAL AORTIC-SURGERY

Purpose: Renal failure remains a common and morbid complication after complex aortic surgery. This study was performed to identify periopera tive factors that contribute to postoperative renal failure. Methods: The perioperative outcomes of 183 patients who underwent thoracoabdomi nal aortic surgery with supraceliac clamping were reviewed. During the interval from Tan. 1987 to Nov. 1996, thoracoabdominal aneurysm repai r was performed in 154 patients (type I, 49 patients [27%]; type II, 2 1 patients [11.5%]; type III, 55 patients [30%]; type TV, 29 patients [16%]), suprarenal abdominal aortic aneurysm repair in 17 patients (9% ), and visceral/renal revascularization procedures in 12 patients (6.5 %). Intraoperative management included thoracoabdominal aortic exposur e and clamp-and-sew technique with renal artery cold perfusion wheneve r the renal arteries were accessible (79% of cases). Results: Relevant clinical features included preoperative hypertension (85%), diabetes mellitus (8%), single functioning kidney (10%), recent intravenous con trast injection (34%), renal insufficiency (creatinine level greater t han 1.5 mg/dl; 24%), and emergent operation (19%). Acute renal failure , defined as both a doubling of serum creatinine level and an absolute value greater than 3.0 mg/dl, occurred in 21 patients (11.5%), of who m five required hemodialysis (2.7%). Variables associated with this co mplication included a preoperative creatinine level greater than 1.5 m g/dl (p = 0.004) and a total cross-clamp time greater than 100 minutes (p = 0.035). The operative mortality risk (within 30 days; 8%) was si gnificantly increased with renal failure (odds ratio, 9.2; 95% confide nce interval, 2.6 to 33; p < 0.005). Conclusions: Renal failure, altho ugh uncommon in contemporary practice, greatly increases the risk of e arly death after thoracoabdominal aortic surgery. The overall incidenc e of renal failure and dialysis requirement in the present series comp are favorably with those reported using other operative techniques, sp ecifically partial left heart bypass and distal aortic perfusion. Thes e data suggest that patients who have preoperative renal insufficiency are prone to postoperative renal failure. Furthermore, regional hypot hermic perfusion and minimal clamp times are important elements in the prevention of renal failure after thoracoabdominal aortic surgery.