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Hyperactive delirium in dementia with Lewy bodies — MRCEM SBA MCQ

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HardMental health and behavioural emergenciesHyperactive delirium in dementia with Lewy bodiesMRCEM SBA

A 74-year-old woman with dementia with Lewy bodies is brought to the emergency department because she has become markedly confused over 18 hours. She usually recognises her daughter despite occasional visual hallucinations; she is now unable to sustain attention or recognise her surroundings. She has a productive cough, temperature 38.4°C, respiratory rate 25/min and right basal crackles. Capillary glucose is 6.1 mmol/L. She repeatedly strikes staff when they approach and prevents assessment and treatment. Her daughter’s reassurance, a quiet room and verbal de-escalation have not reduced the risk. She refuses oral medication. Trained staff, monitoring and resuscitation equipment are available. Which immediate management and disposition plan is most appropriate?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: D — Give intramuscular lorazepam, investigate and treat the suspected infection, and admit under acute medicine.

The acute loss of attention and orientation is a change from her established dementia and suggests delirium. Fever, productive cough, tachypnoea and focal crackles point to a respiratory infection that needs prompt medical investigation and treatment; assessment for delirium, including a 4AT when feasible, should accompany this care. Reassurance and de-escalation were appropriate first steps, but they have failed and her behaviour now prevents essential care. An intramuscular medicine may therefore be needed to make assessment and treatment safe. Dementia with Lewy bodies is the decisive prescribing constraint. Haloperidol is contraindicated because of the risk of serious neurological adverse effects, so A is unsuitable despite its otherwise appropriate medical plan. Intramuscular lorazepam is an option for urgent tranquillisation when oral medication is not possible; use a cautious dose and monitor closely for sedation and respiratory compromise. B cannot address the immediate situation because she refuses oral medication; antipsychotics also require particular caution in Lewy body dementia. C chooses a suitable immediate route and agent, but suspected infection with delirium calls for medical rather than psychiatric admission. E preserves the preferred non-drug approach, but its continuation alone is insufficient while she remains a danger and essential treatment is obstructed.

Reference: NICE CG103: Delirium — recommendations (18 January 2023) — https://www.nice.org.uk/guidance/cg103/chapter/Recommendations NICE NG10: Violence and aggression — recommendations (2015) — https://www.nice.org.uk/guidance/NG10/chapter/recommendations MHRA: Haloperidol (Haldol) — reminder of risks in elderly patients with delirium (10 December 2021) — https://www.gov.uk/drug-safety-update/haloperidol-haldol-reminder-of-risks-when-used-in-elderly-patients-for-the-acute-treatment-of-delirium