Relation between the interval from coronary angiography to selective off-pump coronary artery bypass grafting and postoperative acute kidney injury.

The aim of this study was to investigate whether there are effects of intervals between elective off-pump coronary artery bypass grafting (OPCABG) and coronary angiography (CAG) on postoperative acute kidney injury (AKI). The clinical data of patients undergoing OPCABG and CAG from June 2010 to December 2011 in Beijing Anzhen Hospital were retrospectively analyzed. All the patients were divided into AKI and non-AKI groups. Univariate analysis was performed to find possible factors associated with AKI. Multivariate logistic regression analysis was used to identify whether the short interval was one of the independent risk factors of AKI after adjusting for potential confounding variables. Of 1,513 patients, 529 patients (34.9%) developed AKI. The mortality rate in AKI group (4.9%) was >5× higher than that in non-AKI group (0.9%). The incidence of AKI was highest (56.1%) in patients in whom OPCABG was performed ≤24 hours after CAG. Multivariate logistic regression analysis showed that the interval of ≤24 hours between OPCABG and CAG did increase the risk of AKI (odds ratio 2.15, 95% confidence interval 1.10 to 4.20) after adjusting for the following confounding variables: diabetes mellitus, New York Heart Association heart function class III and IV, lower estimated glomerular filtration rate, numbers of coronary artery bypass grafts ≥3, intraoperative or postoperative intra-aortic balloon pump, intraoperative and postoperative red blood cells transfusion of >3 units, postoperative hypotension, dosage of furosemide of >100 mg/day. In conclusion, it was one of the independent risk factors of postoperative AKI that the OPCABG was performed ≤24 hours after CAG.