Multivariate logistic regression analysis using backward elimination, including four endothelial dysfunction and injury biomarkers, gender, CKD, hepatic failure, coagulation failure, vasopressor use, pulmonary sepsis, and APACHE II scores, showed that among the four biomarkers, only angiopoietin-2 was an independent risk factor associated with severe AKI within the four study days (odds ratio 6.07 per log increase, 95% CI 2.34–15.78, p < 0.001, Table 2). The gene discussed is ANGPT2; the disease is endothelial dysfunction.