Impact of acute kidney injury on prognosis of chronic kidney disease after aortic arch surgery

OBJECTIVES: Postoperative acute kidney injury (AKI) is a common complication associated with increased long-term mortality after cardiothoracic surgery. However, AKI after total aortic arch replacement (TAR) is not well studied. This study aimed to investigate the prognosis and impact of AKI on the long-term outcomes of chronic kidney disease (CKD) patients undergoing TAR. METHODS: We included 208 patients who underwent TAR between September 2003 and December 2014. Patients were divided into a CKD (n = 83, 40%) and non-CKD (n = 125, 60%) group. The definition of AKI followed the Risk, Injury, Failure, Loss of kidney function and End-stage kidney disease (RIFLE) criteria. Independent risk factors for all-cause death and AKI were identified with multivariable analysis. RESULTS: Postoperative AKI was observed in 24 patients (29%) and 39 patients (31%) of CKD and non-CKD groups, respectively. The survival rate of CKD patients was significantly lower than that of non-CKD patients (P = 0.02). Among CKD patients, the 5-year survival rate was 57% in those with AKI group and 92% in those without AKI; prognosis was significantly poorer in patients with AKI (P = 0.001). In the non-CKD group, there was no difference in prognosis between patients with or without AKI (P = 0.77). Multivariable logistic regression analysis revealed that intraoperative blood loss of >= 600 ml was the only predictor of AKI in the CKD group (odds ratio 4.32, P = 0.04). CONCLUSIONS: CKD is associated with reduced long-term survival after TAR. Postoperative AKI strongly influences long-term survival in CKD patients only.