Predictors of acute kidney insufficiency post isolated coronary artery bypass grafting surgery

Background Despite the advances of cardiac surgery in the last decades, the incidence of acute kidney insufficiency (AKI) post isolated coronary artery bypass grafting surgery (iCABG) is increasing. The purpose of this study was to identify the potential predictors of postoperative AKI in iCABG in order to implement measures to reduce its incidence. Results We reviewed the data of 1914 patients who had on-pump iCABG from January 2008 to December 2015, using the cardiothoracic surgery unit database of Liverpool Hospital, Sydney, New South Wales, Australia. Patients were divided into two groups according to the occurrence of postoperative AKI. The incidence of postoperative AKI was 5.3% in 8 years ( n = 101/1914 patients). Multivariable analysis has identified the following independent predictors of postoperative AKI; age older than 80 years (OR 4.27; 95% CI 1.6–11.81) ( p < 0.005), diabetes mellitus (OR 1.96; 95% CI 1.073–3.65) ( p = 0.034), peripheral vascular disease (OR 2.55; 95% CI 1.16–5.59) ( p < 0.01), severe congestive cardiac symptoms (i.e., NYHA III & IV) (OR 1.9; 95% CI 1.26–2.92) ( p = 0.002), surgical re-exploration (OR 2.49; 95% CI 1.07–5.76) ( p = 0.04), postoperative red blood cell (RBC) transfusion (OR 4.93; 95% CI 2.25–10.80) ( p < 0.0001), and postoperative low cardiac output syndrome (OR 2.85; 95% CI 1.49–5.46) ( p < 0.0001). Conclusion Postoperative AKI after iCABG is a complex problem. Predictors of postoperative AKI can be mitigated by accurate risk-based assessment and intraoperative proper surgical hemostasis.