CRP and delirium: Preoperative CRP level reflects the systemic inflammation status of the patients, which may affect the neuroinflammation and blood–brain barrier permeability.[24] Similarly, the preoperative ALB level is indicative of the patients’ nutritional status, a variable with potential repercussions on immune function.[21,24] These factors may predispose the brain to delirium in response to perioperative stressors.