Table 4.

Neurotransmitter-based and other biomarkers reported in research on post-cardiac surgery delirium.

Biomarker	Localization/Function	Research First Author [Reference]	Cardiac Surgery Research Main Findings and Other Main Comments
IGF-1	Serum/growth factor	Çinar [98]	Low pre-operative levels are detected in the delirium group
AChE BChE	Serum/neurotransmitter	John [105]	No evidence in the diagnosis of POD after cardiac surgical procedures
Neopterin	Serum/pteridines	Osse [108]	Preoperative high levels of neopterin
HVA	Serum /amino acid	Osse [108]	Increased postoperative level associated with POD
Cortisol	Serum/hormone	Kazmierski [111]	High plasma levels in delirious patients

Legend: AChE Acetylcholinesterase, BChE Butyrylcholinesterase, HVA homovanillic acid, ICU intensive care unit, IGF-1 Insulin-like growth factor, POD postoperative delirium.