CALCA and delirium: After surgery, PCT was significantly higher in the delirium than the non-delirium group: ICU admission after surgery: 0.08 ng/mL vs. 0.05 ng/mL p = 0.011), and for consecutive days (day 1: 0.59 ng/mL vs. 0.25 ng/mL, p = 0.003; day 2: 1.21 ng/mL vs. 0.36 ng/mL, p = 0.006; day 3: 0.76 ng/mL vs. 0.34 ng/mL, p = 0.001).