Synopsis
Recognise delirium as an acute syndrome of impaired attention while actively identifying focal stroke, seizure, encephalitis and other neurological emergencies that can present through apparent confusion.
- Delirium is an acute, usually fluctuating disturbance of attention and awareness with additional cognitive change. Hyperactive, hypoactive and mixed forms occur; quiet withdrawal is commonly missed.
- Obtain baseline cognition, function and communication from someone who knows the patient, then establish hours-to-days onset, fluctuation and recent precipitant rather than accepting 'confused' as a diagnosis.
- Use the 4AT or the locally mandated validated tool when delirium is suspected, but treat it as a structured assessment rather than a laboratory test that replaces clinical judgement.
Key red flags
Reduced movement, slow responses, sleepiness, poor intake and withdrawal with impaired attention may be mistaken for depression, fatigue or 'pleasant confusion'. It carries substantial risk and requires the same cause search as agitation.
Investigation priorities
Identify altered alertness, impaired attention, acute change and fluctuation in a structured way.
Management branches
Hours-to-days cognitive change, impaired attention or fluctuating alertness without an immediately dominant focal syndrome.
- Perform ABCDE and glucose, obtain collateral baseline, use 4AT or the local validated assessment, and examine for focal neurology, meningism, trauma, pain, retention, constipation and dehydration.
- Investigate and treat plausible precipitants, rationalise medicines and withdrawal risk, and implement orientation, sensory aids, hydration, nutrition, sleep, mobilisation and familiar support.
Key medicines
Short-term haloperidol in exceptional delirium-related distressIf non-drug de-escalation fails and the person remains distressed or dangerous, use the lowest clinically appropriate dose for the shortest possible time, ordinarily no longer than one week, under senior and local policy.