ICU · Neurocritical Care
Aneurysmal subarachnoid haemorrhage
Also known as Subarachnoid haemorrhage (SAH) · Aneurysmal SAH · Vasospasm · Nimodipine · WFNS grading · Cerebral salt wasting
Aneurysmal subarachnoid haemorrhage in the ICU — epidemiology, CT sensitivity by time and the Ottawa SAH Rule, modified Fisher grading, the 2026 ESO/EANS/ESMINT guideline (oral nimodipine, coiling when both options suit, treatment within 24 h, no antifibrinolytics, statins, magnesium or endothelin antagonists), ISAT, DCI definition and monitoring, induced hypertension (Gathier RCT), hyponatraemia and systems of care.
Checked against its sources on 8 Oct 2026
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Red flags
- CT is 100% sensitive only within 6 hours of headache onset — overall sensitivity was 92.9%
- Oral nimodipine for every patient — intravenous nimodipine was not statistically significant in the Cochrane review
- No routine antifibrinolytics before aneurysm treatment (ULTRA: no reduction in poor outcome)
- MAP below 60 mmHg was associated with increased risk of delayed cerebral ischaemia
- Induced hypertension for DCI is unproven — the only RCT showed no benefit and more serious adverse events
Meet the patient
A 52-year-old woman develops a sudden, severe headache while folding laundry, vomits once and develops neck stiffness. Severe sudden-onset headache is the most common presenting symptom of SAH, variably with meningismus and transient or prolonged loss of consciousness. Two questions decide her next fortnight: is there blood on CT, and can the aneurysm be secured before it rebleeds?[1][30]
References31ShowHide
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