Risk Factors for Acute Kidney Injury in Coronary Artery Bypass Graft Surgery Patients Based on the Acute Kidney Injury Network Criteria

Background: Acute kidney injury (AKI) after coronary artery bypass graft surgery (CABG) is a common complication. The present study sought to determine AKI risk factors based on the Acute Kidney Injury Network (AKIN) classification. Methods: In a cross-sectional study, performed from March 2010 to April 2012 at Tehran Heart Center, affiliated with Tehran University of Medical Sciences, 29 independent risk factors for AKI based on the AKIN criteria were examined in isolated post-CABG patients. The patients’ demographic data and risk factors were extracted from the Electronic Database of Tehran Heart Center. According to restricted inclusion and exclusion criteria as well as a creatinine rise to AKI Stage 1, the patients were divided into 2 groups of AKI-negative and AKI-positive and the risk factors were compared between these groups. Results: Out of 3473 included patients at a mean age of 60.78 (±9.46) years, the majority (2474 [71.23%]) were male. Totally, 958 (27.7%) patients had AKI, according to a creatinine rise to AKI Stage 1. Logistic regression analysis demonstrated that higher age (OR=1.021; P<0.001), higher body mass index (OR=1.035; P<0.001), lower preoperative creatinine level (OR=0.417; P<0.001), longer cardiopulmonary bypass time (OR=1.004; P=0.007), blood transfusion in the ICU (OR=1.408; P=0.001), and lack of intraoperative blood transfusion (OR=0.823; P=0.044) were the independent risk factors for AKI after CABG. Conclusion: Based on the findings of the current study, older age, higher body mass index, lower preoperative creatinine level, more blood transfusion in the intensive care unit (ICU), lack of intraoperative blood transfusion, and high cardiopulmonary bypass time may serve as risk factors for the development of AKI in CABG patients.