NEFL and delirium: Furthermore, we did not investigate markers of neuronal injury, such as S-100B, t-tau, neuronal specific enolase (NSE) and neurofilament light chain protein (NFL), which other studies have ﻿investigated 35 This was not possible within the scope of this study, however, future studies will need to examine these biomarkers and their relationship with inflammatory cytokines and the genesis of delirium.