Bleeding into the subarachnoid space, most commonly from a ruptured saccular (berry) aneurysm.
Risk factors
- • Hypertension
- • Smoking, alcohol
- • FHx, ADPKD, Ehlers-Danlos
Clinical features
- • Thunderclap headache 'worst ever'
- • Vomiting, neck stiffness
- • Photophobia, ↓GCS
- • Focal deficit, seizure
Examination
- • Meningism
- • ↓GCS, focal signs
- • Terson syndrome (retinal haem)
Investigations
- • Non-contrast CT head <6 h (>98% sensitive)
- • LP at 12 h if CT negative — xanthochromia
- • CT angiography for aneurysm
Differential diagnosis
- • Migraine
- • Meningitis
- • Cervical artery dissection
- • Reversible cerebral vasoconstriction syndrome
Management
- • Bed rest, analgesia, antiemetics
- • Nimodipine 60 mg PO q4h × 21 d (vasospasm)
- • BP control <160 systolic
- • Endovascular coiling or surgical clipping <72 h
Drug therapy
- • Nimodipine 60 mg q4h
- • Labetalol or nicardipine for BP
Complications
- • Rebleed (peak 24 h)
- • Vasospasm + delayed cerebral ischaemia (day 4–14)
- • Hydrocephalus
- • Hyponatraemia (SIADH/CSW)
Clinical pearls
- • Negative CT after 6 h does NOT exclude SAH — do LP
Related in WardRound
Educational — verify locally.
