Analysis of risk factors for acute renal injury in infants and young children after cardiopulmonary bypass

Abstract

Objective To identify the risk facts for acute kidney injury (AKI) in infants and young children after cardiac surgery with cardiopulmonary bypass (CPB).Methods Data of 161 patients aged ≤3 years undergoing CPB were reviewed retrospectively from September,2012 to January,2013.According to the definition of AKI,they were divided into two groups:AKI group and non-AKI group.After univariate analysis,a binary logistic regression analysis was used to evaluate the independent risk factors in AKI after CPB.The predictive capability of risk factors for AKI was estimated by using an area under the receiver operating characteristic (ROC) curve.Results (1) Of them,23 (14.3％) patients were subjected to AKI after cardiac surgery.(2) Univariate analysis showed that age,body weight,preoperative serum concentration of cystatin C,duration of CPB time,duration of aortic cross-clamp,postponed sternum closure,RACHS-1,postoperative serum creatinine (Scr),postoperative serum cystatin C,inotropic score(IS),postoperative mechanical ventilation time,postoperative pulmonary hypertension,and postoperative nosocomial pneumonia were related to the development of AKI (P ＜ 0.05).Logistic regression analysis showed that the independent risk factors for AKI were postoperative serum cystatin C ≥ 1.02 mg/L (Odd Ratio:8.947),body weight ≤ 5 kg (OR:6.567) and Scr ≥ 35.6 μmoL/L (OR:5.387).Value for the ROC curve was 0.937.Conclusions (1) High risk population might be found out through preoperative evaluation of age,body weight and serum cystatin C before CPB.(2) The present results strongly suggest that postoperative serum cystatin C,body weight and postoperative Scr are risk factors of AKI after CPB,thereby making reliable and early diagnosis and prognosis of AKI. Key words: Infant ; Cardiopulmonary bypass ; Acute kidney injury ; Cystatin C ; Risk factor