Prevalence and Risk Factors of Acute Renal Failure after Cardiac Surgery in Southern Iran

Background: Acute renal failure requiring renal replacement therapy after cardiac surgery is still a cause of major morbidity and mortality worldwide. A number of risk factors for the development of acute renal injury after cardiac surgery have been previously described and based on these variables; several scoring algorithms were proposed. Predictive value of these algorithms in Iran is not described. This study investigates these risk factors among our patients in southern Iran. Methods: Two hundred and forty patients with normal kidney function who were candidates for cardiac surgery were enrolled and their baseline data were collected. Diabetes mellitus and age were selected as more controversial preoperative risk factors. Clamp and pump time were also selected as intra-operative risk factors and the type of operation was also considered as an independent risk factor. The patients were categorized in two groups including group 1: Patients with post-operation normal kidney function and group 2: Patients with postoperation ARF. All patients were followed with serial measurement of serum creatinine post-operation. Results: The incidence of acute renal failure was 11.25%. Mean age of the patients in group 1 was 54.24±15.88 and in group 2 was 52.85±18.20 years. There was not any significant correlation between duration of clamp time and post operation acute renal failure. Clamp time in group 1 was 51.49±11.88 and in group 2 was 53.48±13.40 min. Duration of pump time in group 1 was 63.31±12.56 min and in group 2 was 78.07±10.85 min. The difference was statistically significant. Forty two (20%) of the patients in group 1 and 13 (50%) in group 2 were diabetic. Conclusion: Although several scoring algorithms are available for prediction of post-cardiac surgery complications, these can also be matched with our patients’ criteria enhancing their accuracy for our situation.