HCRT and delirium: However, at the T2 point, the serum cortisol of the patients in the Dexmedetomidine group was significantly lower than that of the Control group (P < 0.05), while the serum 5-HT and hypocretin of patients in the dexmedetomidine group were significantly higher than that of the Control group (P < 0.05), see Fig. 4, then the delirium and postoperative nausea and vomiting (PONV) at 24, 48 h were not significantly different but the PONV at 12 h was significantly lower (Table 2).