Delirium

What is delirium?

Disorder of attention of cognition defined by its acute onset and fluctuating course of symptoms, inattention, impaired level of consciousness, and disturbance of cognition

Key features in diagnosis (4)

• fluctuations

• inattention

• impaired consciousness

• cognitive disturbances

Supportive features of diagnosis

• sleep disturbances

• perceptual disturbances (hallucinations)

• psychomotor disturbances (hypo/hyper activity)

• inappropriate behaviour

• emotional lability

How is delirium diagnosed?

Diagnostic tool: CAM (confusion assessment method)

• FAM CAM - family CAM, identifies delirium from collateral history

What are the 2 major forms of presentation?

Hyperactive:

• increased arousing, agitation, hallucination, sleep disturbances, aggressive

• treatment→ antipsychotics/benzodiazepines

Hypoactive:

• confusion, lethargy, hypoactivity

• greater risk of being missed

• worse prognosis

4AT scoring

CAM assessment

Leading risk factors (8)

• dementia

• functional impairment

• sensory impairment

• alcohol abuse

• comorbidity burden

• poly pharmacy (especially psychoactive drugs)

• physical restraints

• electrolyte disturbance

Key reasons for hospitalised patients (5)

• constipation

• pain

• acute illness

• medications

• change of environment

Pathophysiology

• multiple biological factors interacting → disruption on neuronal networks→ acute cognitive dysfunction

• interference with cellular metabolism/neurotransmission→ cholinergic deficiency/ dopamine excess

• inflammatory changes → neuroinflammation and microglial over activation → neurotics response and neuronal injury

• permanent damage to neurons + cerebrovascular disease + head trauma

Does delirium lead to dementia?

can lead to dementia

• may bring unrecognised cognitive impairments to attention

• commonly coexist, bidirectional relationship

Formal cognitive screening tests

• short portable mental status questionnaire

• Montreall cognitive assessment

• mini-Cog

• CAM, 4As

How is an EEG used for delirium? (4)

•Differentiate functional/psychiatric disorders from organic

•Spot non convulsive epileptic episodes

•Deteriorating dementias

•Creutztfeldt-Jakob

How is an MRI/CT head used for delirium? (4)

•Acute neurological findings

•Hx or signs of fall with head trauma

•Suspected encephalitis

•Decreased level of consciousness and no other etiology

How can a lumbar puncture be used in delirium?

suspected meningitis, encephalitis or subarachnoid haemorrhage. Persistent delirium

What is the Hospital Elder Life Programme? (HELP) (5)

non pharmacological treatment

• reorientation, mobility, therapeutic activities

• reduction of psychoactives, sleep hygiene

• hydration and nutrition

• providing hearing/visual aids

• interdisciplinary team

What pharmacological treatment is used in delirium?

Only use if high risk of self/harm others, or interrupting life sustaining treatment

• rapid tranquillisation with lorazepam 0.5mg or midazolam 1mg IM → reassess every 15 mins

• if important psychotic symptoms, lease with geriatrician or mental health advice on antipsychotics

Treatment for persistent hyperactive delirium >24h

Antipsychotics (1 week or less)

• 1st line quetiapine 25mg

• 2nd line olanzapine 2.5mg

• 3rd line risperidone 250mcg

Check QTc before starting