Table 1.

Causes of delirium in the perioperative period

Preoperative causes	Intraoperative causes	Postoperative causes
Age	Bypass time	Medications (benzodiazepines, steroids, acalcineurin inhibitors)
Disease severity	Surgical complexity
Prior neurological disease (Alzheimers, Parkinson's, prior CVA/TIA)	Perfusion management (MAP, flow rates, temperature, hematocrit)	Sleep deprivation
		Immobility/physical restraints
Previous psychiatric disease (major depressive disorder, schizophrenia/schizoaffective)		Disease severity (low cardiac output requiring need for mechanical support or prolonged high-dose inotropic/vasopressor support)
Substance abuse		Prolonged ICU stay
		Prolonged mechanical ventilation

TIA: Transient ischemic attack, MAP: Mean arterial pressure, ICU: Intensive Care Unit, CVA: Cerebrovascular accident