Comparison of of different equations of creatinine clearance and their prognostic performance in euroscore 2, mortality and acute kindney injury after cardiac surgery, a retrospective cohort study from 2012 to 2019

Abstract

Introduction Eurocore2 is widely used to predict perioperative mortality risk. Preoperative renal function has an important impact on mortality and morbidity after cardiac surgery: in the Euroscore2 renal function is appreciated by the glomerular filtration rate (GFR) calculated by Cockgroft and Could (CC), divided in 4 different categories. Recent studies suggested that different equation will predict more accurately postoperative AKI. The aim of this study was to evaluate if more recent ways to assess renal function (CKD-EPI, MDRD, Mayo-Clinic equation) or the simple preoperative creatinine level (SCr) would improve the accuracy of the euroscore2. Methods We used data of a cohort using our prospective database from September 2012-Juin 2019 of patients undergoing cardiac surgery. We excluded emergent surgery and left heart assistance devices. GFR was calculated with the different equations. We then calculated the Euroscore2 without the weight of the GFR and used statistic regression to build 4 new Euroscore2 including the different GFR (CKD-EPI, MDRD, Mayo-Clinic equation) in a logistic regression as a continuous variable or creatinine level. The area under the ROC curve (AUC) for the to the different Euroscore2 to predicted mortality, for AKI and for hospital stay. AKI was classed with RIFLE criteria. Results We included 3954 patients, with a mean age of 67 years, undergoing mainly for a coronary bypass surgery (37.9%) or valvular surgery (36.6). Overall mortality was 3.2% (127) and was higher (12.6%) in patients with postoperative kidney injury (RIFLE 1 criteria n=842). The AUC for mortality predicted by the Euroscore2 was significantly higher (0.861, p Discussion The Mayo, CKD EPI and MDRD equations might be more specific to predict renal failure. However, it was not possible to improve the mortality prediction of Euroscore using other evaluation of renal function.