TREM2 and delirium: LM‐ and AS‐induced delirium led to microglial activation in the hippocampus as evidenced by up‐regulation of microglial activation‐related genes (such as Il6ra, Tyrobp, Cd68, Aif1, Csf1r, and Trem2) and of relevant inflammatory factors (such as Il‐1β, Tnfα, Ccl2, Ccl5, and Ccl8) (Figure 4D; Figure S6A, Supporting Information).