Diagnosis and Management of Acute Delirium in Geriatric Patients

Etiology and Risk Factors

The American Geriatrics Society recommends that a comprehensive medical evaluation be performed immediately after diagnosis of delirium to identify and address all contributing factors, as delayed treatment prolongs delirium and increases morbidity and mortality 1, 2
Urinary tract infections and pneumonia are the most common infectious causes of delirium in geriatric patients, with over 80% of patients with bacteremia showing neurological symptoms ranging from lethargy to coma 1, 2, 3
Anticholinergic medications, including antihistamines such as cyclizine, are high-risk medications for causing delirium and should be discontinued 1, 2, 3
Benzodiazepines are potent precipitants of delirium and should be discontinued unless used to treat alcohol or benzodiazepine withdrawal 1, 2, 4
Opioids, particularly in patients with renal impairment, can accumulate metabolites and contribute to delirium 2

Dehydration is a common precipitating factor that may not be apparent on initial laboratory examination 2, 3
Hypercalcemia should be suspected even with indolent symptoms such as confusion, asthenia, or somnolence, as delirium due to hypercalcemia is reversible in 40% of cases 2
Hyponatremia due to SIADH may require specific testing beyond basic metabolic panels 2

The American Geriatrics Society recommends a thorough physical examination to identify often-overlooked factors such as pain, constipation, and pressure ulcers 2
Visual and hearing impairments contribute significantly to delirium, and patients should be ensured to use their glasses and hearing aids 1, 2, 3
Sleep deprivation is both a symptom and a factor that prolongs delirium 2
The American College of Emergency Physicians recommends against restraining patients physically to manage behavioral symptoms, as it can worsen delirium 1, 2, 3

A two-step process using the Delirium Triage Screen (very sensitive) followed by the Brief Confusion Assessment Method (very specific) is recommended for delirium screening 3
Delirium screening should be repeated regularly, as mental status can fluctuate 3

Acute mental status changes may be triggered by cerebrovascular disease, including traumatic brain injury and stroke, in elderly patients, according to the American College of Radiology 5, 6
Less frequent neurological causes include status epilepticus, nonconvulsive seizure, intracranial mass effect, chronic subdural or subarachnoid hemorrhage, meningitis or encephalitis, and hydrocephalus, as reported by the American College of Radiology 5, 6

Delirium is considered a medical emergency with mortality rates twice as high if the diagnosis is missed, as stated by the American College of Radiology 5, 6
Overall mortality in patients with altered mental status is approximately 8.1% and is significantly higher in elderly patients, according to the American College of Radiology 5, 6
Up to 10-31% of patients may have delirium at admission, and it may develop in up to 56% of admitted patients, particularly following surgery or in the intensive care unit, as reported by the American College of Radiology 5, 6

The American Geriatrics Society recommends non-pharmacological multicomponent interventions as the primary and first-line approach for managing mild delirium in geriatric patients, with strong evidence supporting their effectiveness and safety 7, 8, 9
Non-pharmacological interventions carry essentially no risk of harm, making them ideal for mild delirium where the risk-benefit ratio of medications is unfavorable 10, 8
The American Geriatrics Society provides a strong recommendation for multicomponent non-pharmacological interventions in the management of delirium, though the quality of evidence is rated as low for treatment 7, 8

Cognitive reorientation, including regular orientation to person, place, time, and situation using simple, clear instructions with visual cues, is a key component of non-pharmacological management 7, 8
Sleep enhancement through non-pharmacological sleep protocols and sleep hygiene measures is recommended 7, 8
Early mobility, including physical rehabilitation and exercise distributed throughout the day in short sessions, can help prevent fatigue 7, 8
Pain management, preferably with non-opioid medications, is an important aspect of non-pharmacological management 11
Adequate oxygenation and prevention of constipation are also crucial components of non-pharmacological management 7, 8

The interdisciplinary team should include physicians, nurses, and potentially physical therapists, occupational therapists, and social workers 7, 8
Healthcare systems should implement formal educational programs with ongoing refresher sessions for all staff on delirium recognition, screening tools, risk factors, and both non-pharmacological and pharmacological approaches 7, 8, 9

Antipsychotics at the lowest effective dose for the shortest duration may be considered only when the patient is severely agitated or distressed, threatening substantial harm to self or others, or when non-pharmacological approaches have been attempted 11, 10
This is a weak recommendation, and medications should never be considered first-line treatment for mild delirium 11
Antipsychotics and benzodiazepines should be avoided for hypoactive delirium and reserved only for severe agitation threatening substantial harm 11

Hyperactive delirium is characterized by agitation, restlessness, heightened arousal, and aggression, which distinguishes it from the often‑missed hypoactive subtype. 12

Hyperactive delirium should not be confused with a primary psychiatric disorder or attributed solely to pre‑existing dementia; it reflects an acute brain dysfunction that requires immediate medical evaluation. 12

More than 50 % of delirium cases go undiagnosed, underscoring the need for a high index of suspicion and systematic use of validated screening tools. 12