Delirium (Acute Confusion) Flashcards
What is delirium?
Acute brain failure
Delirium is a syndrome consisting of…
1) Acute onset, typically over hours or days followed by a fluctuating course
2) Impaired attention and altered awareness
3) A variety of cognitive and neuropsychiatric disturbances
What is the diagnostic criteria for delirium called?
DSM5
What are the 5 parts of DSM5?
1) Disturbance in attention and awareness
2) Disturbance develops over short period of time, is a change from baseline and fluctuates in severity over the day
3) Additional disturbance in cognition
4) Disturbances in 1 and 2 are not explained by other neurocognitive disorders and are not in the context of severely reduced level of arousal e.g. coma
5) Evidence that disturbance is a direct physiological consequence of another medical condition, medication, withdrawal, toxin, or mixture
What is the effect of delirium on dementia?
Increases rate of progression of dementia
What are the predisposing factors to delirium?
1) Dementia
2) Cognitive impairment
3) Previous delirium
4) Functional impairment
5) Visual impairment
6) Hearing impairment
7) Comorbidity
8) > 75
9) Depression
10) Alcohol misuse
What the the precipitating factors of delirium?
1) Drugs (psychoactive and sedatives + anticholinergics)
2) Physical restraints
3) Bladder catheter
4) Dehydration/electrolyte disturbance
5) Infection
6) Hip fracture
7) Major surgery
8) Pain
9) Polypharmacy
10) Constipation (can be due to codeine/morphine)
What is the mnemonic to remember causes of delirium?
DELIRIUM
What are the causes of delirium under DELIRIUM?
1) Drugs/Dehydration
2) Electrolyte imbalance (hypercalcaemia/hyponatraemia)
3) Level of pain
4) Infection/Inflammation (post surgery)
5) Respiratory failure
6) Impaction of faeces
7) Urinary retention
8) Metabolic disorder (liver/renal failure, hypoglycaemia)/MI
What is the pathophysiology of delirium?
- Complicated
- Likely to be > 1 cause
- Cholinergic deficiency, dopaminergic excess
What are the two types of delirium?
Hyperactive and hypoactive
What are the features of hyperactive delirium?
1) Increased confusion
2) Hallucinations/delusions
3) Sleep disturbances
4) Less co-operative
5) Restless, agitated, aggressive
What are the features of hypoactive delirium?
1) Poor concentration
2) Less ware
3) Reduced mobility/movement
4) Reduced appetite
What is mixed delirium?
Mixture of hyperactive and hypoactive
What are the % in how common the different types of delirium are?
20% hyperactive
40% hypoactive
30% mixed
What is carphologia (can occur in hyperactive delirium)?
Tugging at bed sheets/picking at lint
What do you need to consider when assessing delirium?
1) Think delirium
2) Age 65 or older
3) Cognitive impairment/dementia
4) Current hip fracture
5) Severe illness
What are two methods for assessing delirium?
1) CAM (confusion assessment method)
2) 4-AT
What are the sections of the CAM and how do you use to it diagnose delirium?
1) Acute onset and fluctuating course
2) Inattention
3) Disorganised thinking
4) Altered consciousness (hypo or hyper alert)
- To diagnose need 1 and 2 + 3/4
How do you assess acute onset and fluctuating course?
1) Identifying change from baseline
2) Collateral history (family and staff) → has pt been more confused lately?
3) Have there been fluctuations across hours and days?
How do you assess inattention?
1) Difficulty maintaining attention or shifting attention between tasks
2) May be manifested by vagueness, distracted by sounds, objects, thoughts
3) Bedside tests of attention → counting backwards numbers or months
How do you assess disorganised thinking?
1) Problems making sense of what is going on
2) Misinterpreting the environment e.g. real stimulus but misinterpreting situation
3) May be hallucinations or persecutory ideas
4) Mumbling or rambling speech which is difficult to understand
How do you assess altered consciousness level?
- Hyper alert → agitated, restless, aggressive, disturbed sleep
- Hypo alert → sleepy, withdrawn, no interest in environment, poor oral intake
What is the 4-AT?
A brief clinical instrument for delirium detection with basic orientation questions
What is involved in taking a full history of a delirious patient?
1) Ask for potential causes of delirium
2) Alcohol/drugs and medication history
3) Collateral history from family/friends/staff
What is involved in a full examination of a delirious patient?
1) Full examination for causes of delirium
2) Look for infection, dehydration, sensory impairment e.g. broken glasses, hearing aid on side, external head injury
3) Baseline cognitive assessment e.g. AMT, MMSE
4) Assess for presence of delirium
5) Assess for pain → pressure sores, constipation
What are high risk medications for delirium?
1) Analgesics
2) Anticholinergics
3) Antidepressants
4) Sedative-hypnotics
5) Corticosteroids
6) Dopamine agonists
What are low risk medications for delirium?
1) Cardiovascular agents
2) Antimicrobials
3) Anticonvulsants
4) Gastrointestinal agents
5) Skeletal muscle relaxants
What investigations should you do to diagnose delirium?
1) FBC, U&E, calcium, glucose, LFT
2) Microbiology
3) Pulse oximetry
4) ECG
5) CXR
6) Neuroimaging → subdural haemorrhage esp. in patients on blood thinners
7) Lumbar puncture
8) EEG
9) Consider ABG, drug levels, B12, TFTs, ammonia, cortisol, vitamin B12
What are common differential diagnoses of delirium?
1) Depression
2) Dementia
3) Another psychotic diagnosis
4) Non-convulsive epilepsy
How do you manage delirium?
1) Address acute medical issues
2) Re-orientate
3) Maintain safety
4) Promote normal sleep-wake cycle
5) Monitor symptoms of delirium and record progress
Describe pharmacological treatment of delirium (last resort)
- Start low dose and review daily
- Should be short term (<1 week)
- Haloperidol → do ECG first
- Lorazepam → if antipsychotics are contraindicated
- Chlordiazepoxide for alcohol withdrawal
- Can prolong delirium if sedative
When are antipsychotics contraindicated?
- Parkinson’s
- Lewy body dementia
- Seizures
- Elongated QTc (>470ms)
