What is the management of suspected subarachnoid hemorrhage?

Management of Suspected Subarachnoid Hemorrhage

Suspected subarachnoid hemorrhage (SAH) requires immediate diagnostic evaluation with non-contrast head CT, followed by lumbar puncture if CT is negative, and rapid transfer to a high-volume neurosurgical center for definitive treatment. 1

Initial Evaluation and Diagnosis

• SAH is a medical emergency that is frequently misdiagnosed (up to 12% of cases); maintain high suspicion in patients with acute onset of severe headache 1
• Initial diagnostic workup should include:
  • Non-contrast head CT scan as the first-line diagnostic test 2, 1
  • If CT is negative but clinical suspicion remains high, perform lumbar puncture to analyze CSF for xanthochromia and bilirubin 2, 1
  • CT sensitivity is highest (98-100%) within the first 12 hours after SAH, declining to 93% at 24 hours and 57-85% by day 6 1
• Assess clinical severity using validated scales (Hunt and Hess Scale, Fisher Scale, Glasgow Coma Scale, or World Federation of Neurological Surgeons Scale) as it is the most useful indicator of outcome 2, 1

Initial Management

• Ensure adequate airway, breathing, and circulation; consider intubation for patients with decreased level of consciousness or inability to protect airway 2
• Control blood pressure with a titratable agent to balance the risk of stroke, hypertension-related rebleeding, and maintenance of cerebral perfusion pressure 2, 1
• Transfer patients to high-volume centers with experienced cerebrovascular surgeons and multidisciplinary neurocritical care services 1, 3
• Begin oral nimodipine 60 mg every 4 hours for 21 consecutive days, starting within 96 hours of hemorrhage onset 1, 4
  • Nimodipine improves neurological outcomes but does not prevent cerebral vasospasm itself 4
  • If the patient cannot swallow, extract the contents of the capsule with a syringe and administer through a nasogastric tube 4

Definitive Treatment

• Secure the aneurysm as early as feasible to reduce the risk of rebleeding 1, 3
  • The risk of "ultraearly rebleeding" (within 24 hours of initial SAH) may be 15%, with 70% occurring within 2 hours of initial SAH 1
• For patients with ruptured aneurysms amenable to both techniques, endovascular coiling should be considered as the first option over surgical clipping 1, 3
• Complete obliteration of the aneurysm should be the goal whenever possible 1

Management of Complications

Hydrocephalus

• Acute symptomatic hydrocephalus should be managed by cerebrospinal fluid diversion (external ventricular drainage or lumbar drainage) 1, 3
• Chronic symptomatic hydrocephalus should be treated with permanent cerebrospinal fluid diversion 3

Delayed Cerebral Ischemia (DCI)

• Maintain euvolemia and normal circulating blood volume to prevent DCI 1, 3
• Induction of hypertension is recommended for patients with DCI unless blood pressure is elevated at baseline or cardiac status precludes it 1
• Prophylactic hypervolemia and triple-H therapy are not recommended as they can increase complications 3

Monitoring and Follow-up

• After aneurysm repair, immediate cerebrovascular imaging is recommended to identify remnants or recurrence 1, 3
• In the absence of contraindications, patients should have delayed follow-up vascular imaging, with consideration for retreatment if there is a clinically significant remnant 1
• Transcranial Doppler ultrasonography can be used to monitor for vasospasm development 3

Common Pitfalls and Considerations

• Misdiagnosis is common in SAH; maintain high suspicion with acute severe headache 3
• Hypervolemia is potentially harmful and associated with excess morbidity; euvolemia should be the target 3
• Bedrest alone does not reduce the risk of rebleeding and should be part of a broader treatment strategy 2
• Routine prophylactic anticonvulsants are not recommended for all patients with SAH 3