Patient-specific risk factors can be classified as:
It is important to identify patients at high risk for delirium in the ED and initiate preventive strategies when indicated.
For patients with predisposing risk factors, several nonpharmacologic interventions can be implemented early to help prevent delirium. For example, providing glasses or hearing aids to patients with sensory impairment, allowing extended hours for family at bedside, trying to expedite admission or discharge.
Drugs, dehydration, deprivation (sleep)
Electrolyte abnormalities (Na, Ca)
Lack of drugs (withdrawal)
Infection, ingestion
Reduced sensory input
Intracranial problems, increased pain
Urinary retention
Metabolic problems, malnutrition
Drug levels: digoxin, lithium, acetaminophen, salicylate
Most common meds that lead to delirium are those with psychoactive effects: sedatives-hypnotics, narcotics, meds with anticholinergic effects.
Differential for delirium is broad. Need to consider metabolic derangements, infection, acute neurologic or cardiac event, urinary retention, severe constipation, etc.
1potentially modifiable predisposing risk factors
Ahmed S, et al. Age Ageing. 2014;43(3):326–333.
Aslaner MA, Boz M, Celik A, et al. Etiologies and delirium rates of elderly ED patients with acutely altered mental status: a multicenter prospective study. Am J Emerg Med. 2017;35(1):71–76
Elie M, et al. J Gen Intern Med. 1998;13(3):204–212.
Inouye SK. Clin Geriatr Med. 1998;14(4):745–764.
Naeije G, Pepersack T. Delirium in elderly people. Lancet. 2014;383(9934):2044–2045
ADL, activities of daily living
ED, emergency department