Abstract:

Background:To define acute kidney injury (AKI) that develops following coronary artery bypass grafting (CABG) surgery using RIFLE classification system and to determine the risk factors affecting the early and late mortality of the patients who developed acute kidney injury. Materials and Methods: A total of 213 patients who underwent isolated CABG operation in our clinic between February 2016 and September 2018 were retrospectively investigated. Preoperative and postoperative estimated glomerular filtration rates were calculated for all patients. The diagnosis and severity of AKI was determined by RIFLE classification. Results: The median age of the patients included in the study was 62, of whom 114 were male. In the postoperative period, AKI was detected in 65 (30.5%) patients according to RIFLE classification. 63.1 % of the patients were in stage R, 23.1 % were in stage I, 13.8 % were in stage F.  L and E stages of AKI did not develop in any patients. Comorbid conditions such as diabetes mellitus, hypertension, congestive heart failure and peripheral artery disease, and the duration of cardiopulmonary bypass (CPB) were detected to be independent risk factors for the development of AKI. Bleeding revision need for hemodialysis, usage of intra aortic balloon pump and respiratory complications were higher in the AKI group than in the non-AKI group. In addition, in-hospital and long term mortality rates were significantly higher in AKI group. As the severity of AKI increased, the survival rates of the patients were decreased. The patients in stage –F had the lowest survival rate. Conclusion: RIFLE classification is a low-cost and easy-to-use tool to detect AKI developing after CABG surgery and it helps to detect kidney injury at the initial stage. This classification provides a prediction about the mortality and morbidity of the patients who developed AKI following CABG surgery.