Preoperative chronic kidney disease as a strong predictor of postoperative infection and mortality after coronary artery bypass grafting

Abstract

Background: The aim of this study was to determine the influence of preoperative kidney dysfunction (ie, chronic kidney disease (CKD)) on postoperative cardiovascular events, infection, acute kidney injury and hospital mortality in patients undergoing coronary artery bypass grafting (CABG). Methods and Results: A multi-institutional retrospective study was performed at 14 hospitals of adult patients undergoing isolated CABG from 2007 to 2008 (n=1,522). We classified CKD level according to preoperative estimated glomerular filtration rate (eGFR): normal, eGFR >90 ml•min–1•1.73 m–2; mild, eGFR 60–90 ml•min–1•1.73 m–2; moderate, eGFR 30–59 ml•min–1•1.73 m–2; and severe, eGFR <30 ml•min–1•1.73 m–2, and assessed postoperative outcome. Preoperative CKD distribution was as follows: normal, n=121 (8%); mild, n=713 (47%); moderate, n=515 (34%); and severe, n=169 (11%). Risk of infection was strongly correlated with CKD level (normal, 3.3%; mild, 7.0%; moderate, 8.3%; severe, 17.0%; P<0.01). The risk of in-hospital death was also strongly correlated with CKD level (normal, 1.7%; mild, 1.0%; moderate, 1.6%; severe, 5.9%; P<0.01). On multivariate logistic regression analysis, CKD level was identified as a significant risk factor for postoperative infection, acute kidney injury, and in-hospital death. Conclusions: Advanced preoperative CKD is a strong predictor of postoperative infection, acute kidney injury and in-hospital death after CABG.