CXCL8 and endothelial dysfunction: The top 6 biological variables including two PERSEVERE biomarkers IL-8 and HSP70 and four endothelial dysfunction markers ICAM-1, thrombomodulin, Angpt-2/Angpt-1, Angpt-2/Tie-2, selected based on a relative variable importance threshold of > 50% of top predictor, were used to develop simplified TreeNet® models to estimate risk of death or persistent organ dysfunctions on day 7 of septic shock.