Risk Factors For Acute Kidney Injury Associated With Extracorporeal Membrane Oxygenation

BACKGROUNDExtracorporeal membrane oxygenation(ECMO)is a salvage treatment therapy for reversible cardiopulmonary failure in critically ill patients who are ineffective for traditional clinical treatment.Due to the complexity of ECMO technology and long duration of ECMO support,patients with ECMO have a high incidence of complications.Acute kidney injury(AKI)is one of the common critical complications,which is closely related to poor prognosis.AKI can easily cause fluid overload and multiple organ failure,increase the risk of chronic kidney disease,end-stage renal disease and death,prolong the length of hospital stay,increase medical expenses,and seriously affect the quality of life of patients.So far,the treatment of AKI is limited.Therefore,early identification of risk factors for ECMO-associated AKI and timely prevention are of great significance to avoid aggravating the progression of the disease and improve the clinical outcome of patients.At present,the exact pathogenesis of ECMO-associared AKI has not been fully clarified.There are few studies on the risk factors for adult ECMO-associared AKI,and there are few studies on the risk factors for laboratory indicators.In this study,the risk factors for ECMO-associared AKI were further discussed by collecting the general clinical data and routine laboratory indicators of patients.OBJECTIVE:To understand the incidence and clinical characteristics of ECMO-associated AKI,and to explore the risk factors and the impact on prognosis.METHODSThrough the medical record system,159 patients receiving ECMO support in Henan Province People’s Hospital from January 2017 to October 2019 were collected retrospectively.After excluding 25 patients who did not meet the requirements,a total of 134 patients were included in the study.According to the AKI clinical practice guideline proposed by Kidney Disease:Improving Global Outcomes(KDIGO)in 2012,the patients were divided into AKI group and non-AKI group,and patients with AKI were further divided into stages 1,2 and 3.The clinical data and laboratory indexes were compared between two groups.The variables with P<0.15 in univariate analysis were included in the regression model,and multivariate logistic regression analysis was used to analyze the risk factors for ECMO-associated AKI.The correlation between AKI stage and prognosis was analyzed by Spearman rank correlation test.RESULTS1.Of the 134 patients with ECMO included in the study,there were 81 patients with AKI.The incidence rate of AKI was 60.4%,including 24 patients of AKI stage 1,22 patients of AKI stage 2 and 35patients of AKI stage 3.2.There were no statistically significant differences in causes of admission and causes of ECMO support between AKI group and non-AKI group(P>0.05).3.AKI group had higher percentages of hypertension and infection,and longer of duration of ECMO,and more transfusion of red blood cells and plasma than non-AKI group,statistically significant differences(P<0.05).There were no statistically significant differences in Age,sex ratio,percentages of heart diseases and diabetes,acute physiology and chronic health evaluationⅡ,left ventricular ejection fraction,percentages of cardiopulmonary resuscitation and intra aortic balloon counterpulsation,mode of ECMO,pump speed of ECMO,blood flow rate of ECMO,mechanical ventilation time,and transfusion of platelet between two groups(P>0.05).4.AKI group had higer levels of C-reactive protein and lactate than non-AKI group before ECMO,statistically significant differences(P<0.05).There were no statistically significant differences in white blood cell count,hemoglobin,platelet count,albumin,alanine aminotransferase,aspartate aminotransferase,total bilirubin,direct bilirubin,and indirect bilirubin between two groups before ECMO(P>0.05).5.Multivariate logistic regression analysis showed that hypertension(OR=2.442,95%CI:1.005～5.935,P=0.049),infection(OR=5.980,95%CI:2.182～16.388,P=0.001),and the increase of lactic acid level before ECMO(OR=1.150,95%CI:1.037～1.275,P=0.008)were independent risk factors for ECMO-associated AKI.6.AKI group experienced higher mortality than non-AKI group(P<0.05),and it was positively correlated with the AKI stage(r_s=0.290,P=0.009).CONCLUSIONS1.The incidence of AKI in patients receiving ECMO support was 60.4%,which was a common complication of patients receiving ECMO support.2.Hypertension,infection and the increase of lactate level before ECMO increased the risk of ECMO-associated AKI.3.AKI increased the risk of death in patients receiving ECMO support,and AKI stage was closely related to mortality.The higher the stage,the higher the mortality.