A study by Feng et al. [24] evidenced how an altered transient hyperemia response test (THRT) evaluated with TCCS in the first 6 h after resuscitation in patients with shock, was an independent predictor of SAD [OR 5.77]; patients with delirium presented a poorer outcome (survival at 28 days), a higher APACHE II score, increased biomarkers for neuronal damage (NSE, neurospecific enolase), increased ICU length of stay, and more days of ventilation. Here, ENO2 is linked to delirium.