ACUTE RENAL FAILURE AFTER CARDIAC SURGERY
Acute renal failure (ARF) following cardiac surgery occurs in 1 to 10% of patients. Patients who develop ARF have higher rates of mortality. This study was undertaken to estimate the role of perioperative variables in predicting of post cardiac surgery ARF. We studied a cohort of 398 adult patients who underwent cardiac surgery at our institution from February 2004 to February 2006. Adult patients who were scheduled for cardiac valvular surgery, coronary artery bypass grafting (CABG) or both, with or without cardiopulmonary bypass (CPB) were included. Exclusion criteria were death within two days of operation (n= 8), incomplete patient data, and preexisting renal dysfunction and dialysis requirement or a baseline serum creatinine > 4 mg/dl. Age, sex, left ventricular ejection fraction, diabetes, preoperative, presence of proteinuria (on dipstick), type of surgery, use of CPB and duration of surgery were recorded. A logistic regression analysis was performed to assess independent contribution of variables in the risk of ARF. A binary logistic regression revealed age was an independent predictor of ARF (P < 0.05). When both all variables were included in a multinominal logistic regression model, preoperative proteinuria independently predicted ARF (Odds ratio= 3.91, 95% CI: 1.55-9.91, P = 0.004). Our results revealed that special considerations should be given to elderly and patients with proteinuria when managing post cardiac surgery ARF.