Prediction Of Postoperative Acute Kidney Injury In Patients With Acute Type A Aortic Dissection Using Cystatin C

Objective:The research aimed to predict postoperative acute kidney injury in patients with acute type A aortic dissection preliminarily by exploring the correlation of preoperative serum cystatin C level and incidence of postoperative acute kidney injury and combining with relevant risk factors.Methods:The research was a case-control study.249 patients of Qilu Hospital of Shandong University from January 2018 to December 2020 were enrolled in the research according to the predetermined inclusion and exclusion criteria.Patients were divided into acute kidney injury group(n=93)and non acute kidney injury group(n=156)according to the occurrence of postoperative acute kidney injury.Results:Postoperative acute kidney injury occurred in 93 patients(37.35%).The univariable analysis indicated differences between groups of male(P=0.049),preoperative history of hypertension(P=0.002),white blood cell count(P<0.001),alanine aminotransferase(P=0.025),aspartate aminotransferase(P=0.028),indirect bilirubin(P=0.012),serum creatinine(P<0.001),blood urea nitrogen(P<0.001),cystatin C(P<0.001),postoperative duration of mechanical ventilation(P<0.001)and intensive care unit length of stay(P<0.001),postoperative acute respiratory failure(P=0.001),postoperative nervous dysfunction(P<0.001),death within 30 days after surgery(P<0.001)were significant statistically.The preoperative variables above were enrolled into the multivariable analysis.The result indicated preoperative history of hypertension(OR:3.766;95%CI:1.637-8.665;P=0.002),white blood cell count(OR:1.128;95%CI:1.031-1.234;P=0.009),cystatin C(OR:6.606;95%CI:3.549-12.295;P<0.001)might be independent risk factors of postoperative acute kidney injury.The crude analysis(P<0.001)and subgroup analysis(P<0.001;P=0.019)of survival curve both indicated that preoperative level of cystatin C was correlated with postoperative acute kidney injury.The dataset was divided into the training set and validation set randomly according to the ratio of 7:3.Lasso regression was used to reduce the dimension of variables,and the variables whose coefficient was larger than 0.01 when λ=0.04102031 were taken into the building of prediction model.The clinical prediction model(https://auguster.shinyapps.io/DynNomapp/)was developed based on the multivariable logistic analysis.The internal validation demonstrated that the Concordance statistics(C-index)were 0.801(training set 95%CI:0.732-0.871)and 0.741(validation set 95%CI:0.620-0.862),respectively.The net benefit of the model was better between threshold probabilities of 0.25-0.99 in decision curve analysis.Conclusion:The research showed that the preoperative serum cystatin C level was correlated with the incidence of postoperative acute kidney injury.The incidence of postoperative acute kidney injury might be correlated with poor prognosis.Preoperative serum cystatin C combined with related risk factors might contribute to the prediction of postoperative acute kidney injury in patients with acute type A aortic dissection.