What is the recommended management for subarachnoid hemorrhage?

Management of Subarachnoid Hemorrhage

Immediate Diagnosis and Initial Stabilization

Obtain 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

Definitive Aneurysm Treatment

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

Nimodipine Administration (Critical for All Patients)

Administer oral nimodipine 60 mg every 4 hours for 21 consecutive days starting within 96 hours of hemorrhage onset. 3, 4

• Nimodipine reduces cerebral infarction by 34% and poor outcomes by 40%, though it does not prevent angiographic vasospasm 5
• This is a Class I, Level of Evidence A recommendation 3
• Never administer nimodipine intravenously—this can cause life-threatening hypotension 4
• If the patient cannot swallow, extract capsule contents with an 18-gauge needle into an oral syringe labeled "Not for IV Use" and administer via nasogastric tube followed by 30 mL normal saline flush 4
• Avoid grapefruit juice, which interferes with metabolism 4

Managing Nimodipine-Related Hypotension

• Significant blood pressure drops (>10%) occur in 30% of patients after IV formulation initiation and 9% after oral doses 6
• In patients with severe liver dysfunction, reduce dose to 30 mg every 4 hours with close blood pressure monitoring 4
• If recurrent hypotension occurs, reduce dose by 50% rather than discontinuing entirely, as full-dose nimodipine is associated with better outcomes (OR 0.895, p=0.029) 7
• Support blood pressure with vasopressors (noradrenaline) rather than stopping nimodipine when possible 6

Prevention and Management of Delayed Cerebral Ischemia

Maintain euvolemia and normal circulating blood volume; avoid prophylactic hypervolemia and hemodynamic augmentation. 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
• This approach reduces progression and severity of delayed cerebral ischemia 3
• If hemodynamic augmentation fails, consider endovascular balloon angioplasty for proximal vessels or intra-arterial vasodilators (verapamil preferred over papaverine due to lower risk of elevated intracranial pressure) for distal vessels 3

Hydrocephalus Management

Treat acute symptomatic hydrocephalus with external ventricular drainage or lumbar drainage depending on clinical scenario. 3, 1

• Acute hydrocephalus occurs in 15-87% of patients and requires cerebrospinal fluid diversion (Class I, Level of Evidence B) 3
• Do not wean external ventricular drainage over >24 hours, as this does not reduce need for permanent shunting 3
• Chronic symptomatic hydrocephalus (occurring in 8.9-48% of survivors) requires permanent cerebrospinal fluid diversion with ventriculoperitoneal shunt placement 3, 2

Invasive Monitoring

• Invasive monitoring (intracranial pressure monitoring, arterial lines) is useful in high-grade subarachnoid hemorrhage patients with limited neurological examination 3

Follow-Up Imaging and Surveillance

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
• Give strong consideration to retreatment if clinically significant or growing remnants are identified 2
• In younger patients with multiple aneurysms or ≥2 first-degree relatives with subarachnoid hemorrhage, continue surveillance imaging at ≤5-year intervals to detect de novo aneurysms 3, 2

Long-Term Management and Rehabilitation

Refer all survivors for comprehensive multidisciplinary evaluation including cognitive, behavioral, and psychosocial assessments using validated screening tools. 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
• Consider noninvasive screening for additional aneurysms in patients with familial subarachnoid hemorrhage 2

Medications to Avoid

• Do not use routine statin therapy or intravenous magnesium for vasospasm prophylaxis 3
• Aspirin, enoxaparin, and tirilazad have been shown ineffective 3

Common Pitfalls

• Misdiagnosing subarachnoid hemorrhage occurs in up to 12% of cases—maintain high suspicion with acute severe headache 1
• Discontinuing nimodipine prematurely due to hypotension rather than dose-reducing and supporting blood pressure with vasopressors 7
• Inadequate follow-up after endovascular coiling leads to missed recurrences 2
• Failing to address cognitive and behavioral deficits significantly impacts quality of life 3, 2