Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.
Raised intracranial pressure from brain metastases
Essential points for quick revision.
2 min synopsisUK scopeSources checked 27 Aug 2026Clinical review pending
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Impending cerebral herniation
Declining consciousness, a new fixed or unequal pupil, abnormal posturing, repeated vomiting, seizure, bradycardia with hypertension or rapidly progressive focal deficit suggests critical intracranial mass effect.
Action: Use neuroprotective ABCDE care with head elevation, urgent glucose and blood gas, give dexamethasone for tumour-associated vasogenic oedema, treat seizure, obtain immediate CT when it is the fastest safe study and contact neurosurgery, critical care and acute oncology for decompression and definitive planning.
Synopsis
Recognise intracranial mass effect and impending herniation, stabilise airway and cerebral perfusion, define metastatic number and anatomy with appropriate imaging and coordinate corticosteroid, neurosurgical, radiosurgical and systemic treatment.
Brain metastases cause raised pressure through tumour volume, vasogenic oedema, haemorrhage and obstructive hydrocephalus; posterior-fossa lesions can deteriorate with little reserve.
Key features are progressive headache worse with cough or lying flat, vomiting, papilloedema, focal deficit, seizure, cognitive change and declining consciousness.
Immediate CT head is the first emergency study for herniation, haemorrhage or sudden deficit because it is fast; contrast-enhanced MRI is the reference standard for detecting and planning brain metastases when stable.
Key red flags
Reduced consciousness, pupillary asymmetry, abnormal posturing or a Cushing physiological pattern requires immediate herniation management.
Focal cortical syndrome
Weakness, aphasia, neglect, visual-field loss or focal seizure localises a lesion or haemorrhage and requires urgent imaging.
Investigation priorities
01
First emergency non-contrast CT headFirst step
Detect haemorrhage, major mass effect, hydrocephalus and shift rapidly in an unstable or suddenly deteriorating patient.
Management branches
DeterioratingProtect brain and identify herniation
Consciousness, pupils, posture, breathing or focal neurology is worsening rapidly.
Use ABCDE with cervical-neutral head elevation, oxygen for hypoxaemia, glucose and blood gas, seizure control and avoidance of hypotension and hypercapnia.
Give dexamethasone promptly for suspected tumour-associated oedema, obtain immediate CT and contact neurosurgery, critical care and acute oncology together.
Stable symptomaticDefine all intracranial disease
A cancer patient has new headache, focal symptom, seizure or cognitive change without herniation physiology.
Key medicines
Dexamethasone for symptomatic cerebral oedemaUse 4 to 8 mg daily orally or intravenously in divided doses for mild to moderate symptoms and up to 16 mg daily for severe raised-pressure or focal symptoms under the acute neuro-oncology protocol, then taper as rapidly as clinically tolerated.
Levetiracetam after seizureA common adult starting regimen after a brain-tumour seizure is levetiracetam 500 mg orally or intravenously twice daily, increased according to recurrence, renal function and specialist neurology advice.
National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.