Geriatrics - Delirium Flashcards
What is the definition of delirium?
Delirium is a state of mental confusion that develops rapidly and usually fluctuates in intensity. The key features are an acute onset with a fluctuating course. It is often referred to as an acute confusional state.
What are the key diagnostic criteria for delirium?
These are outlined in the DSM-IV.
Key features are:
1) disturbance of consciousness
2) worsening confusion
3) tendency to fluctuate during the course of the day with disturbance of the sleep wake cycle
4) evidence that the delirium is caused by general medical condition, drug withdrawal or intoxication
How can disturbances of consciousness be assessed in a patient with delirium?
Disturbance of consciousness is one of the key diagnostic criteria for diagnosing delirium (remember that ALL 4 must be present for a diagnosis to be made).
The key is reduced attention, which is the ability to focus, sustain or shift mental focus. It is mostly observed during interviews, but can test it with tasks that require concentration - e.g. counting backwards, serial 7’s or digit span
What are other associated clinical features of delirium?
As well as the core diagnostic features there are several associated features:
- delusions (often paranoid)
- emotional changes (anxiety, depression, fear)
- motor changes (slowness, restlessness, agitation)
- hallucinations (often formed and animated)
Delusions if present tend to be fleeting and lack any thought or logic.
What is hypoactive or apathetic delirium?
This type of delirium is hard to spot. The patient is withdrawn, quiet, lacks initiative and responds poorly to interaction.
How common is delirium?
It is very common in the in hospital setting, with a prevalence of about 20%.
Patients with dementia are 5-10 times more likely to develop delirium.
Why is it important to “think delirium”?
Delirium is associated with:
- increased mortality (1 year mortality following an admission with delirium is 40%)
- prolonged hospital admission
- higher complication rates
- 3x increased risk of developing dementia
Delirium should be taken seriously because it more often points to a serious underlying medical problem that requires investigation.
What factors predispose to delirium?
Patients with these risk factors are more likely to develop delirium. They include:
- sensory impairment
- multiple co-morbidities
- physical frailty
- older age (>65)
- dementia
What factors precipitate delirium?
These risk factors are associated with causing delirium in susceptible patients. They include:
- metabolic abnormalities (e.g. electrolyte disturbances)
- hypoxia
- acute brain disease
- systemic infection
- drug interaction/ withdrawal
- surgery
“PINCH ME” is a good mnemonic to help remember the causes of delirium: Pain, Infection, Nutrition, Constipation, Hydration/ Hypoxia, Medication, Environmental
How can delirium be prevented?
Patients who are at high risk (i.e. those with significant predisposing factors) should be identified on admission and prevention strategies incorporated into their care plans:
- keep orientated, promote familiar
- facilitate vision and hearing
- keep hydrated and well fed
- reduce medication, avoid anticholinergic drugs and opioids if possible
- promote night time sleep
What are the 3 types of delirium?
1) hypoactive (40%) - easy to miss
2) hyperactive (25%)
3) mixed (30%)
What are the features of hypoactive delirium?
Characterised by apathy, withdrawal, lethargy and reduced motor responses.
It is the most common type of delirium but often goes unrecognised. It can be mistaken for depression.
These patients have longer in hospital stays and are associated with increased risk of complications - e.g. pressure sores.
What is hyperactive delirium?
This is characterised by increased motor activity and associated agitation, hallucinations and challenging behaviour.
This type of delirium is most likely to be recognised but patients are often inappropriately treated - e.g. with sedating drugs.
How should a patient with delirium be assessed?
A logical assessment of any patient follows history, examination, investigation and management.
What are important features of history taking in a patient with delirium?
An accurate history is often difficult to obtain in a patient with delirium.
1) Gain a collateral history from family members, friends, care home workers, GPs etc
2) As well as presenting complaint, think about other important pieces of information to gather:
- onset and course of confusion
- symptoms suggestive of underlying disease
- co-morbidities
- previous episodes of confusion
- previous forgetfullness or confusion, has this progressed?
- drugs history
- alcohol history
- sensory deficits (i.e. previous stroke)
- functional status
