Acute renal failure associated with cardiac operations. A case-control study.

We performed a case-control study to identify risk factors for the development of acute renal failure after cardiac operations. Forty-two cases of acute renal failure were identified in a total of 572 patients who underwent cardiac operations. They were matched with a control population of patients having cardiac operations without acute renal failure. Discriminant analysis performed with preoperative variables revealed preoperative serum creatinine values, concurrent valve and bypass surgery, and age to be significant variables for identifying patients at risk for acute renal failure. The use of these three variables in a discriminant model correctly classified 77% of patients. The addition of intraoperative variables did not significantly improve the ability of the model to correctly classify patients. Acute renal failure was associated with a significant increase in the number of postoperative complications, mortality, and length of hospitalization and intensive care unit stay.