Flashcards in Geriatrics - Delirium Deck (29):
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 The patient is withdrawn, quiet, lacks initiative and responds poorly to interaction.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)
What factors precipitate delirium?
These risk factors are associated with causing delirium in susceptible patients. They include:
- metabolic abnormalities (e.g. electrolyte disturbances)
- acute brain disease
- systemic infection
- drug interaction/ withdrawal
"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
- previous episodes of confusion
- previous forgetfullness or confusion, has this progressed?
- drugs history
- alcohol history
- sensory deficits (i.e. previous stroke)
- functional status
What are the key areas to examine in a patient with delirium?
- conscious level: determine level of consciousness, using either GCS or AVPU
- cognitive function: use abreviated mental test score (AMT) or mini mental state exam (MMSE)
- infection screen: examine carefully for sources of infection, remove bandages and check for pressure sores (also think about urine, blood cultures and chest x ray if indicated)
- nutrition and hydration: assess
- constipation: rule out urinary retention and constipation by performing an abdominal exam and a DRE; consider a post micturition bladder scan
- neurology: perform full neurological exam
- mental state exam (MSE)
What are the questions asked as part of an AMT?
(AMT = Abbreviated Mental Test score). This is the routine test that all elderly patients receive when they are admitted to hospital. Remember that an AMT is only a screening tool, and if positive requires following up.
There are 10 questions that are asked, and they cover the following areas:
Age, Time, Address for recall, Year, Name of hospital, Recognition of 2 people, DOB, Year of first world war, Name of current Monarch, Count backwards from 20-1
What score on the AMT is considered abnormal?
A score of less than 8/10 is abnormal. But, this in itself does not make a diagnosis of delirium certain. If a patient scores less than 8/10 on AMT the next step is to perform the Confusion Assessment Method (CAM).
What is the CAM?
The CAM assessment involves assessing a patient for 4 features. The diagnosis of delirium by CAM requires the presence of features 1 and 2 and either 3 or 4.
Feature 1 = acute onset and fluctuating course
Feature 2 = inattention (does the patient have difficulty focusing attention, for example being easily distracted)
Feature 3 = disorganised thinking (is the patients thinking incoherent or disorganised, are they rambling?)
Feature 4 = altered level of consciousness (e.g. alert, lethargic, vigilant, stupor, coma)
Name some important 1st line investigations needed in cases of delirium?
FBC, ECG, CRP, Glucose, LFTs, U&Es, Ca, TFT, CXR, Urinalysis
What are some 2nd line investigations you may consider in a patient with delirium?
MRI head, CT head, specific cultures (e.g. sputum, blood), EEG, ABG, LP
What are the 4 main management principles in patients with delirium?
1) Treat the underlying cause
2) Manage the symptoms of delirium
3) Prevent complications
4) Patient and relative explanations
How is the underlying cause of delirium treated?
Once identified, it is essential to treat the underlying cause of delirium:
- Treat infection
- Correct hypoxia or metabolic abnormality
- Remove any offending medication
How as the symptoms of delirium best managed?
Whilst treating the underlying cause, attention needs to be given to relieving symptoms of delirium:
- nurse in a well lit, quiet environment
- promote orientation (e.g. clocks, orientation boards)
- analgesia as required but avoid opiates
- maintain hydration and nutrition
- good sleep hygiene
- regular clinical updates with relatives and encourage them to be in attendance
- use the least restrictive option with patients
- keep sedative drugs to a minimum
- avoid agreeing with rambling speech, tactfully change subject
- keep sedative drugs to a minimum
What are the complications of delirium and how can they be avoided?
- falls +/- injury
- pressure sores
- nosocomial infections
- medication side effects
- functional decline
These can be avoided by:
- good continence care
- MDT approach
- pressure ulcer prevention and prompt treatment
- attention to hydration and nutrition
What are the 2 main uses of sedative drugs in the context of patients with delirium?
Sedative drugs should be kept to a minimum in patients with delirium. They can also precipitate delirium in susceptible individuals.
They can be used for:
1) Rapid tranquilisation of an agitated patient who poses a risk to themselves and others
2) short term control of distress
What drugs are used for short term control of distress in patients with delirium? What are their maximum daily doses?
1) Haloperidol - 5mg/ 24 hour (0.5mg PO, 1-2mg IM)
2) Lorazepam - 3mg/24 hour (0.5-1mg PO, 0.5-1mg IM)
What is the most appropriate dosing schedule for an agitated patient with PD when the oral route is not possible?
Lorazepam 0.5-1mg IM would be the most appropriate drug, with a maximum daily dose of 3mg.
Haloperidol is contraindicated due to its extrapyramidal side effects. It is always advisable to start with the lowest dose possible.