Neuro - Delerium

Question 1

What is delirium?

Answer 1

Disturbance of consciousness with a change in cognition that develops over a short time period and has a fluctuating course.

1 Disordered thinking
2 Reduced attention
3 Abnormal sleep/wake cycle
4 Abnormal psychomotor activity
5 Abnormal perceptions
6 Abnormal emotional behaviour

Question 2

How can delirium be classified?

Answer 2

There are three main subtypes of delirium:
1 Hyperactive delirium (~1%)
– Confused
– Agitated
– Combative, aggressive
– Paranoid

2 Hypoactive delirium (35%)
– Inattentive
– Stuporous
– Withdrawn
– Often mistaken for depression

3 Mixed (64%)

Question 3

What are the risk factors for ICU delirium?

Answer 3

Patient factors:
- age- depression
- prior cognitive impairment
- alcoholism
- hypertension
- smoking
- prior sensory impairment

Illness factors:
- anaemia
- Hypoxiaemia
- acidosis
- metabolic disturbances
- sepsis
- illness severity

Iatrogenic/environmental:
- sleep disturbance
- pain
- medication (anticholinergics and sedatives)

Question 4

How might you assess for delirium in the ICU?

Answer 4

CAM-ICU assessment:
1. Acute onset or fluctuating course (Y/N)
2. Inattention (errors >2)
3. Altered level of consciousness (e.g. RASS anything other than zero)
4. Disorganised thinking (errors >1)1+2 & 3 or 4 = CAM-ICU positive

Question 5

Why is delirium important?

Answer 5

Delirium is associated with:
1 Short term complications:
– Risk of adverse events including accidental extubation / line removal

2 Medium term complications:
– Increased LOS on ICU and in hospital
– Increased duration of mechanical ventilation
– Increased mortality (independent risk factor for three-fold increase in mortality at 90 days)

3 Long term complications:
– Risk of post-traumatic stress disorder (PTSD)
– Risk of long term cognitive impairment

Question 6

How is delirium managed?

Answer 6

1 The ABCDE bundle (Vasilevskis, et al, Chest, 2010) can be used
– Awake and Breathing (daily sedation holds +/– spontaneous breathing
trials (SBTs) to reduce the amount of sedation given and total days of
mechanical ventilation)
– Choice of sedation (minimising the use of medications that can provoke
delirium, e.g. benzodiazepines)
– Coordination (regular orientation and ensuring patients have their glasses
and hearing aids)
– Delirium monitoring (with CAM-ICU or similar)
– Early mobilisation has been shown to reduce acute cognitive and physical
dysfunction in ICU patients

2 Sleep hygiene

3 Removing invasive devices when no longer required