UCHL1 and delirium: Tau protein at day 3 (15.3 [10.4, 25.1] pg/ml vs. 10.4 [5.2, 13.4] pg/ml, p = 0.019), as well as UCHL-1 at day 3 (25.2 [20.2, 35.7] pg/ml vs. 11.2 [9.3, 21.3] pg/ml, p = 0.034) and day 5 (20.7 [16.5, 27.2] pg/ml vs. 9.1 [6.8, 17.0] pg/ml, p = 0.023) were significantly higher in patients with delirium compared to non-delirious children.