Delirium

New agitation with fluctuating attention, altered awareness, pain, retention, constipation, infection

EmergentReview due

At a glance

High risk: Yes
Onset: Acute
Course: Fluctuating
Treatable: Often

Safety snapshot

Sepsis, hypoxia, hypoglycaemia, stroke, intracranial bleed, alcohol/benzo withdrawal, urinary retention, faecal impaction.

Watch forSepsishypoxiastrokewithdrawalhaemorrhageeclampsia

Presentation hinge

Inattention plus altered awareness/arousal are the key separators. Usually precipitated by acute illness, surgery, injury, retention, constipation, pain, or medicines.

Separates the Psychomotor Agitation group. It is not specific to Delirium.

Do now

1Screen with 4AT and record the baseline cognitive state from a collateral history
2Look for the precipitant: infection, urinary retention, constipation, pain, hypoxia, electrolytes, alcohol or benzodiazepine withdrawal
3Review every anticholinergic and sedating agent on the chart and stop what is not essential
4Correct the reversible cause first and reserve antipsychotics for distress or risk that non-drug measures have not settled

Locally authored, reviewed by PsychSift on 27 September 2026

Clinical review

Rows marked “Whole group”: Applies to the Psychomotor Agitation group — not specific to Delirium

Why it fits

New agitation with fluctuating attention, altered awareness, pain, retention, constipation, infection

Key features6 features

Subjective bodily torment and urge to move dominate. Mood or psychosis may be absent.
Fluctuating attention, confusion, sepsis, haemorrhage, pre-eclampsia/eclampsia, metabolic derangement
Psychotic or manic syndrome with abrupt change from baseline in the postpartum period.
Cognitive impairment, fluctuating attention, fear, pain
Aggression is often fear- or belief-driven rather than predatory.
Acute change, fluctuating course, inattention

Must-not-miss

Sepsis, hypoxia, hypoglycaemia, stroke, intracranial bleed, alcohol/benzo withdrawal, urinary retention, faecal impaction.

High-risk causes8 causes

Sepsis
hypoxia
stroke
withdrawal
head injury
medication toxicity
haemorrhage
eclampsia

Bedside question

Applies to the Psychomotor Agitation group.

Inattention plus altered awareness/arousal are the key separators. Usually precipitated by acute illness, surgery, injury, retention, constipation, pain, or medicines.

Helpful clues7 clues

Subjective bodily torment and urge to move dominate. Mood or psychosis may be absent.
Psychotic or manic syndrome with abrupt change from baseline in the postpartum period.
Aggression is often fear- or belief-driven rather than predatory.
Inattention and fluctuation dominate. Psychotic content is often fragmented or changeable.
Usually chronic, internally generated but experienced as alien, embedded in broader psychotic syndrome.
Formal thought disorder plus broader psychotic syndrome and functional deterioration.
Acute and fluctuating with inattention = delirium (medical/toxic cause).

Immediate action

Applies to the Psychomotor Agitation group.

In older or medically unwell patients, assume delirium until proved otherwise Cannabis and stimulants can closely mimic primary psychosis Reassess once partially cleared Escalate early to medical/neurology review if red flags are present Consider MRI, EEG, CSF, and autoimmune testing when the syndrome is atypical Clarify positive symptoms, negative symptoms, cognition, and functional trajectory

Priority steps8 steps

1Violence in psychosis is often defensive from perceived threat
2Mixed irritability is easy to underestimate
3One of the commonest reversible drivers of acute violence
4Agitation in dementia is frequently delirium, pain, or environment-driven
5Recognising the interpersonal trigger can prevent the next escalation
6Do vitals, BGL, sats, attention testing, collateral, and medication/substance review early
7Use 4AT in most adult settings, and ICU tools where appropriate
8Quiet hypoactive delirium is commonly missed

Investigations

Applies to the Psychomotor Agitation group.

Neuroimaging (CT/MRI), EEG, Lumbar puncture / CSF studies

Core tests5

Blood glucose
Vitals and oxygen saturation
Neuroimaging (CT/MRI)
EEG
Lumbar puncture / CSF studies

Mimics / overlap

Applies to the Psychomotor Agitation group.

Primary psychosis, dementia, severe depression, catatonia, intoxication, post-ictal state, stroke, medication overdose, stimulant intoxication

Consider8

Do now

1Screen with 4AT and record the baseline cognitive state from a collateral history
2Look for the precipitant: infection, urinary retention, constipation, pain, hypoxia, electrolytes, alcohol or benzodiazepine withdrawal
3Review every anticholinergic and sedating agent on the chart and stop what is not essential
4Correct the reversible cause first and reserve antipsychotics for distress or risk that non-drug measures have not settled

Locally authored, reviewed by PsychSift on 27 September 2026

First-line tests

Applies to the Psychomotor Agitation group — not specific to Delirium

Blood glucose
Vitals and oxygen saturation
Neuroimaging (CT/MRI)
EEG
Lumbar puncture / CSF studies

Watch for

Sepsis
hypoxia
stroke
withdrawal
haemorrhage
eclampsia

Also consider

Source and review

Review due· Unverified

v10 · exported 2026-07-11

Clinical reference — not validated decision support. Review before use.