ABSTRACT
Objective:To explore the risk factors of acute kidney injury(AKI)after liver transplantation(LT), examine its prognostic impact and construct a clinical prediction model.Methods:Clinical data are retrospectively reviewed for 220 LT recipients.They are divided into two groups of AKI(93 cases)and non-AKI(127 cases)according to the occurrence of AKI post-LT.Clinical data of two groups are compared.The variables with statistically significant inter-group differences in univariate analysis are included for multivariate analysis for obtaining the independent risk factors for AKI post-LT.Then the independent risk factors are employed for fitting a prediction model and a visual nomogram is constructed.At the same time, discrimination and calibration of the prediction model are evaluated.Extubation time, length of intensive care unit(ICU)stay, continuous renal replacement therapy(CRRT)rate, length of hospital stay, in-hospital mortality, estimated glomerular filtration rate(eGFR)at discharge, incidence of chronic renal failure(CRF)and readmission times are compared between two groups.Survival analysis is also performed between AKI and non-AKI groups and AKI 0/1 and AKI 2/3 stages.Results:The incidence of AKI post-LT is 42.3%.Age( OR=1.036, 95% CI: 1.001~1.073), preoperative serum creatinine level( OR=1.030, 95% CI: 1.011~1.049), platelet count( OR=0.992, 95% CI: 0.985~0.999), Child-Pugh class C( OR=2.678, 95% CI: 1.031~6.952), postoperative abdominal infection( OR=2.271, 95% CI: 1.120~4.603)and abdominal hemorrhage( OR=3.869, 95% CI: 1.016~14.72)are independent risk factors for AKI post-LT.The AUC/C-index of nomogram prediction model is 0.789 with a Brier score of 0.183, showing decent discrimination and calibration.According to the nomogram score, the recipients with a risk of AKI>50% are included into high-risk group while those with a risk of AKI<50% into low-risk group.Postoperative survival of low-risk group is better than that of high-risk group( P<0.001).Compared with non-AKI group, AKI group had a later extubation time( P=0.003), a longer length of ICU stay( P<0.001)and hospital stay( P=0.001), a higher rate of CRRT usage( P<0.001)and in-hospital mortality( P<0.001), a lower eGFR at discharge( P<0.001)and a higher incidence of CRF( P<0.001).Postoperative survival of non-AKI group was better than that of AKI group( P=0.048).Postoperative survival of patients with AKI 0/1 is better than that of those with AKI 2/3( P=0.002). Conclusions:Advanced age, high preoperative serum creatinine, low preoperative platelet, poor preoperative liver function, postoperative abdominal infection and abdominal hemorrhage may elevate the risks of AKI post-LT.And the nomogram prediction model based upon the above risk factors has a high value of clinical application.