Clinical Study On Risk Factors Of Acute Kidney Injury After Liver Transplantation

Objective: The aim of this study was to investigate clinical characteristics and risk factors of acute kidney injury(AKI)in patients following liver transplantation.Additionally,we explored the clinical outcomes of patients with acute kidney injury(AKI).Methods: This was a retrospective observational study that collected date from intensive care unit(ICU)at Beijing Friendship Hospital,Capital Medical University,all the patients following liver transplantation admitted to ICU from 1 June 2013 to 31 October 2016 were included.Patients under kidney transplantation at the sametime or ever for kidney transplantation or underwent retransplantation or with endstage renal dysfunction rely on renal replacement therapy or diagnosed AKI before transplantation were excluded.AKI was diagnosed and classified according to the KDIGO criteria,adults and children were separately analysed.Information recorded from patients' charts included demographic characteristics,previous history of hypertension,diabetes mellitus,previous liver disease,MELD score.Preoperative laboratory values were also recorded: creatinine,albumin,Tbil,ALT,AST.From the intraoperative period,we recorded: duration of surgery,cold /warm ischemia time,fluid balance.Postoperative factors included: days of ICU,overall in-hospital stay and 28 day mortality rates.Univariate analysis was used to identify the difference between the two groups,and then logistic regression analysis was used to find the risk factors of acute kidney injury,and ROC curve will be used to form prediction model.Results: Among the 279 patients after liver transplantation,there were 124 adults(?18 y),68(54.8%)developed AKI according to KDIGO category,66.2%(45)of the patients belonged to the stage 1,13.2%(9)to the stage 2,and 20.6%(14)to the stage 3.There were 155 children(<18y),38(24.5%)developed AKI according to KDIGO category,47.4%(18)of the patients belonged to the stage 1,36.8%(14)to the stage 2,and 15.8%(6)to the stage 3.Multivariable logistic regression analysis revealed that the development of AKI was associated with intraoperative hypotension duration(OR=1.020),excessive loss of blood(OR=1.036)and fluid balance during surgery(OR=1.015)in adults,dividing value was 27.5min,32.5ml/kg,31.2ml/kg,AUC was 0.662 [ p=0.002,95% CI(0.567,0.757)],0.637 [ p=0.009,95% CI(0.540,0.734)],0.624 [ p=0.017,95% CI(0.526,0.723)].Preoperative PLT,preoperative infection and the length of time of vena cava occlusion were risk factors for children,dividing value for the first one and the last one was 210×109/L and 29.5min,AUC was 0.634 [ p=0.013,95% CI(0.526,0.741)],0.657 [ p=0.004,95% CI(0.561,0.790)],0.676 [ p=0.015,95% CI(0.561,0.790)].Conclusion: The incidence rate of AKI is 54.8% in adults.The risk factors for adults are intraoperative hypotension duration,excessive loss of blood and fluid balance during operation.AKI is independently associated with longer duration of hospitalization in adults.The incidence rate of AKI is 24.5% in children.The risk factors for children are preoperative PLT and infection,and the length of time of vena cava occlusion.AKI is independently associated with higher 28 day mortality rate.