OBJECTIVE: Acute renal failure following heart surgery is a major complication. The aim of this study was to evaluate if duration of cardiopulmonary bypass (CPB) is an important factor that influences kidney dysfunction. METHODS: One hundred and sixteen patients from a single center referred for heart surgery were evaluated. Demographic factors, clinical data, operative and postoperative variables were evaluated. Serum creatinine and creatinine clearance were calculated until the fifth postoperative day. Acute renal failure was defined as the requirement of dialysis therapy. Patients were divided into two groups, the CPB<70min Group, patients with CPB duration equal to or less than 70 minutes and the CPB<90min Group, patients with CPB duration equal to or more than 90 minutes. RESULTS: The median increases in serum creatinine were 0.18 + 0.41(CPB<70min) and 0.42 + 0.44 (CPB>90min p=0.005). Dialysis was indicated in 1.3% (CPB<70min) and 12.5% 90min - p = 0.018). The odds ratio for dialysis was 1.12 (95% CI; 1.00-1.20) for CPB>90min. There was no significant difference in mortality (5.2 versus 7.5%, p = 0.631). CONCLUSION: The greatest likelihood of developing kidney failure after heart surgery is observed when CPB is at least 90 minutes, although creatinine clearance was not significantly altered between the groups studied.
Extracorporeal circulation; Renal insufficiency; Dialysis
