Raised intracranial pressure
Raised ICP (mass, bleed, oedema, hydrocephalus) → herniation risk
Overview
A pathological rise in intracranial pressure that threatens cerebral perfusion and risks herniation ("coning"). Recognised by the headache/vomiting/papilloedema triad and falling GCS with pupil change; managed by treating the cause and temporising measures. The neuro emphasis: do NOT LP if a mass/raised ICP is suspected.
Recognise
- Headache (worse lying/on waking), vomiting, papilloedema, reduced GCS
- Cushing reflex (LATE): hypertension + bradycardia + irregular breathing
- A new fixed dilated pupil = uncal herniation compressing CN III
Red flags
- Falling GCS, new fixed dilated pupil, Cushing reflex → impending herniation; neurosurgical emergency
Differentials & how to tell them apart
Investigations
Urgent CT head; do NOT LP if raised ICP/mass suspected (coning risk); identify the cause.
Management
Treat the cause; temporise (head-up 30°, normocapnia, osmotic therapy); urgent neurosurgery
- 1ABC; nurse head-up 30°, maintain oxygenation/normocapnia, avoid hypotension; urgent CT + neurosurgical referral.Gate: Do NOT perform an LP when raised ICP/a mass is suspected — it can precipitate fatal coning
- 2Osmotic therapy to temporise; dexamethasone only for tumour oedema; definitive treatment of the cause (evacuate haematoma, CSF diversion, decompression).
Key points
A unilateral fixed dilated pupil = third-nerve compression from herniation. The Cushing reflex is late/pre-terminal. The neuro exam point: no LP if raised ICP.
Monitor & prognosis
GCS, pupils, BP/HR, repeat imaging; ICP monitoring in ICU.
Depends on cause and speed of decompression.
Source: NICE NG232 (head injury); neurosurgical guidance