Management of Subarachnoid Hemorrhage

Diagnosis and Initial Management

The American Heart Association recommends obtaining noncontrast head CT immediately; if negative and clinical suspicion remains high, proceed directly to lumbar puncture looking for xanthochromia and elevated bilirubin 1
CT sensitivity is 98-100% within 12 hours but declines to 93% at 24 hours and 57-85% by day 6, making early imaging critical 1
Rapidly assess clinical severity using Hunt and Hess or World Federation of Neurological Surgeons scales, as initial grade is the strongest predictor of outcome 1
Control blood pressure with titratable agents between symptom onset and aneurysm obliteration, balancing rebleeding risk against maintaining cerebral perfusion pressure 1

Perform surgical clipping or endovascular coiling as early as feasible to reduce rebleeding risk, with endovascular coiling preferred when both techniques are feasible 1
Rebleeding risk is highest in the first 24 hours (15% "ultraearly rebleeding"), with 70% occurring within 2 hours of initial hemorrhage 1
For aneurysms amenable to both approaches, endovascular coiling is associated with lower long-term seizure rates compared to surgical clipping 2
Complete aneurysm obliteration should be achieved whenever technically possible 1

Administer oral nimodipine 60 mg every 4 hours for 21 consecutive days starting within 96 hours of hemorrhage onset, as recommended by the American Heart Association 3
Nimodipine reduces cerebral infarction by 34% and poor outcomes by 40%, though it does not prevent angiographic vasospasm 4, 5
This is a Class I, Level of Evidence A recommendation 4, 5

Maintain euvolemia and normal circulating blood volume; avoid prophylactic hypervolemia and hemodynamic augmentation, as recommended by the American Heart Association 3
Prophylactic triple-H therapy (hypervolemia, hypertension, hemodilution) should not be performed to minimize iatrogenic risks 3
For symptomatic delayed cerebral ischemia, elevate blood pressure (induced hypertension) and maintain euvolemia 3, 4
This approach reduces progression and severity of delayed cerebral ischemia 3

Treat acute symptomatic hydrocephalus with external ventricular drainage or lumbar drainage depending on clinical scenario, as recommended by the American Heart Association 4, 1
Acute hydrocephalus occurs in 15-87% of patients and requires cerebrospinal fluid diversion (Class I, Level of Evidence B) 4
Do not wean external ventricular drainage over >24 hours, as this does not reduce need for permanent shunting 4

Invasive monitoring (intracranial pressure monitoring, arterial lines) is useful in high-grade subarachnoid hemorrhage patients with limited neurological examination 3
Obtain immediate post-treatment cerebrovascular imaging to identify aneurysm remnants, then perform delayed follow-up imaging at 6 and 18 months 2, 1
For coiled aneurysms, follow-up angiography at 6 months and 18 months is recommended 2

Refer all survivors for comprehensive multidisciplinary evaluation including cognitive, behavioral, and psychosocial assessments using validated screening tools, as recommended by the American Heart Association 3, 2
Physical, cognitive, behavioral, and quality of life deficits are common and can persist long-term 3
Early identification of mood disorders allows for interventions that improve long-term outcomes 3
Target systolic blood pressure <160 mm Hg in the chronic phase to prevent aneurysm recurrence 2

Do not use routine statin therapy or intravenous magnesium for vasospasm prophylaxis, as recommended by the American Heart Association 3
Aspirin, enoxaparin, and tirilazad have been shown ineffective 6