Abstract: 【Abstract】Objective To evaluate the clinical characteristics and risk factors affecting the outcome of severe acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI) patients treated with extracorporeal membrane oxygenation (ECMO) combined with continuous renal replacement therapy (CRRT). Methods The severe ARDS and AKI patients required ECMO and CRRT and treated in the Intensive Care Unit (ICU) of Tongji Hospital from October 2016 to October 2020 were retrospectively studied. Clinical characteristics of the patients were analyzed. According to the survival situation within 28 days after VV-ECMO treatment, the patients were divided into survival group and death group. We compared the clinical data of the two groups at the time transferred to ICU, before and after VV-ECMO and CRRT treatment. Unconditioned logistic regression analysis was carried out to determine the independent prognostic risk factors. Results Fiftyfour patients were enrolled in the study, of whom 26 patients survived and 28 patients died. Compared with the death group, the sequential organ failure assessment (SOFA) of the survival group was significantly lower (11.8±2.4 vs. 13.7±1.9, t=-2.550, P=0.015), and the ECMO to CRRT interval was significantly shortened (4.7±3.3h vs. 11.4±6.7h, t=-3.024, P=0.005). During treatment processes, the fluid balance at ECMO day 3 in the
survival group was statistically reduced than death group (373±210ml vs. 987±482ml, t=-4.990, P=0.001). Unconditioned logistic regression analysis showed that the ECMO to CRRT interval, the fluid balance at ECMO day 3, and the SOFA score were the independent risk factors affecting patient prognosis (OR=0.254, 0.302 and 0.467, respectively; 95% CI=0.085～0.656, 0.025～0.498 and 0.217～0.887, respectively; P=0.009, 0.012 and 0.029, respectively). Conclusions The prognosis of severe ARDS and AKI patients required ECMO combined with CRRT depends mainly on the ECMO to CRRT interval, the fluid balance at ECMO day 3 and the SOFA score.

Key words: Extracorporeal membrane oxygenation, Continuous renal replacement therapy, Acute respiratory distress syndrome, Prognosis, Risk factors