# Confused over a day and a half, a 79-year-old in a care home: a case to work up

> A geriatric medicine case for medical students: a 79-year-old who has become sleepy, frightened and aggressive over a day and a half. Delirium versus dementia, what to ask, first tests and the causes to find.

- Geriatric Medicine · Intermediate · about 20 minutes
- Web page: https://www.medikarya.in/case-studies/79-year-old-man-in-a-care-home-who-has-become-confused
- Work up this patient: https://www.medikarya.in/case-studies/79-year-old-man-in-a-care-home-who-has-become-confused

## How the patient presents

Over the last day and a half, a 79-year-old man in a residential home has become sleepy, frightened and aggressive, accuses the staff of plotting against him, keeps falling and has become incontinent. The staff think he has dementia and want him moved. The nurse in charge gives you the story.

## Why sudden confusion in an older person matters

A change in behaviour over hours or days is delirium until proven otherwise, not dementia getting worse. Delirium is a medical emergency with a cause to find: often an infection, a medicine, dehydration, or urine or stool that is not passing.

## What to ask in the history

- How he was before: memory, behaviour, what he could do
- When the change started; does it come and go
- New or changed medicines
- Falls, head injury
- Passing urine, bowels
- Eating and drinking
- Pain
- Fever, cough
- Alcohol

## Red flags

- A fall with a head injury, especially on blood thinners
- Fever
- Drowsiness
- Signs on one side of the body
- Not eating or drinking

## What to examine

- Observations, glucose
- Hydration
- Bladder (is it full), constipation
- Chest, skin, mouth
- Neurological examination
- A short delirium screening test

## First investigations

- Glucose
- Full blood count, CRP
- Sodium, calcium, kidney and liver function
- Urine culture, without relying on a dipstick at his age
- Chest X-ray, ECG
- CT head after a fall or with focal signs or blood thinners
- A review of every medicine

## Differential diagnosis of sudden confusion in an older person

Grouped, not ranked. Which one fits this patient is for you to work out in the case.

### Causes of delirium

- Infection
- Medicines that act on the brain
- Dehydration
- Low or high sodium, high calcium
- Urinary retention or constipation
- Low oxygen
- Alcohol withdrawal

### In the brain

- Subdural haematoma
- Stroke
- Seizure

### Not delirium

- Dementia getting worse, only once delirium is excluded
- Depression or psychosis

## Common mistakes

- Putting it down to dementia.
- Diagnosing a urine infection from a dipstick.
- Sedating him before looking for the cause.

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A study guide for medical students, not medical advice. Follow your institution's protocols in practice.