Delirium in older adults: approach and management

1. Recognise it

2. Immediate assessment: stabilise first

1. ABCDE assessment
   • Check oxygen saturation, blood pressure, pulse, temperature, respiratory rate, and capillary glucose.
   • Treat hypoxia, hypoglycaemia, shock, severe pain, seizures, or hyperthermia immediately.
2. Establish baseline
   • Ask family or carers: “When was the patient last normal?”
   • Obtain premorbid cognition, mobility, function, alcohol use, drug history, and recent illness or operation.
3. Look for red flags requiring urgent escalation
   • Focal neurological signs, headache, head injury, seizure, meningism.
   • Sepsis or haemodynamic instability.
   • Hypoxia or hypercapnia.
   • Suspected poisoning, alcohol or sedative withdrawal.
   • Severe agitation risking injury.
   • New inability to swallow or maintain hydration.

3. Find and correct the cause

• Pain, particularly unrecognised fracture, urinary retention, constipation, pressure injury.
• Infection: pneumonia, urinary infection only if symptoms/signs support it, skin, intra-abdominal, sepsis.
• Nutrition and dehydration: poor intake, electrolyte abnormalities, renal failure.
• Constipation.
• Hypoxia: pneumonia, pulmonary embolism, heart failure, COPD exacerbation, anaemia, hypercapnia.
• Medications: recent additions, dose changes, polypharmacy, anticholinergics, opioids, benzodiazepines, sedatives, antihistamines, steroids, dopaminergic drugs, withdrawal states.
• Environment and endocrine/metabolic causes: unfamiliar surroundings, sleep deprivation, sensory deprivation, hypoglycaemia/hyperglycaemia, sodium/calcium disturbance, thyroid disease, hepatic or uraemic encephalopathy.

4. Investigations, guided by history and examination

• Bedside glucose, ECG, pulse oximetry, blood gas if respiratory compromise is possible.
• FBC, urea/electrolytes/creatinine, calcium, liver tests, CRP, and other tests based on context.
• Urinalysis and urine culture only when urinary symptoms, systemic infection signs, or no better source exists.
• Chest radiograph if respiratory symptoms, hypoxia, fever, or aspiration risk.
• Blood cultures before antibiotics if sepsis is suspected.
• Bladder scan for retention; rectal examination only when appropriate for suspected impaction.
• CT brain for trauma, focal neurology, reduced consciousness, anticoagulation with possible bleed, or unexplained persistent delirium. Do not order routine neuroimaging for every case.

5. Non-drug management is first-line

• Explain simply and repeatedly what is happening.
• Use familiar staff where possible; involve family or carers.
• Ensure glasses, hearing aids and dentures are available and working.
• Promote orientation: clock, calendar, daylight, familiar objects, regular reorientation.
• Maintain hydration, nutrition, pain control, oxygenation and bowel/bladder care.
• Mobilise early with assistance.
• Protect sleep: reduce overnight noise, avoid unnecessary observations and procedures.
• Avoid ward moves, physical restraints, and indwelling catheters unless essential.
• Review all drugs daily and stop or reduce non-essential deliriogenic medications.
• Arrange one-to-one observation if safety is a concern.

6. Treat distress or dangerous behaviour

• Use the lowest dose for the shortest possible time, with frequent review.
• NICE advises considering short-term haloperidol, generally for no more than one week, only after de-escalation has failed or is inappropriate.
• In older adults, check for QT prolongation and cardiac risk, extrapyramidal adverse effects, Parkinson disease, and dementia with Lewy bodies.
• Avoid haloperidol in Parkinson disease or Lewy body dementia unless specialist advice supports an alternative.
• Avoid benzodiazepines routinely because they can worsen delirium. They are mainly appropriate for alcohol withdrawal, benzodiazepine withdrawal, or seizures, with specialist-led care.

7. Monitor and follow up

• Document baseline and serial cognition, 4AT, behaviour, hydration, intake, mobility, sleep, and likely cause.
• Review response to treatment daily and remove temporary measures promptly.
• If delirium does not settle, reassess for missed or multiple causes, medication effects, pain, retention/constipation, withdrawal, neurological illness, and underlying dementia.
• At discharge, communicate the episode to primary care and family. Reassess cognition after recovery because delirium can reveal previously unrecognised dementia.

Key exam summary