Management of Patients With Aneurysmal Subarachnoid Hemorrhage: Guidelines From the AHA and ASA

Aneurysmal subarachnoid hemorrhage (SAH) presents at a mean age of 55 years and affected patients are more likely to be Black, female, or tobacco users or have hypertension. Although patients rarely have a family history of cerebral aneurysm, two or more first-degree relatives with the condition confers a 12% prevalence of cerebral aneurysm. The American Heart Association (AHA) and American Stroke Association (ASA) released guidelines for the management of patients with aneurysmal SAH.

Classically, aneurysmal SAH presents with sudden-onset headache that immediately reaches its maximum intensity. Warning or sentinel headaches precede up to 43% of these hemorrhages. Aneurysmal SAH can be ruled out in alert patients 15 years or older with sudden-onset nontraumatic headache that reaches maximum intensity within 1 hour, and who have none of the signs or symptoms listed in the Ottawa SAH rule: age 40 years or older, neck pain or stiffness, witnessed loss of consciousness, onset during exertion, thunderclap headache, or limited neck flexion on examination.

All other patients should receive noncontrast computed tomography (CT) of the head, which, if obtained within 6 hours of onset, has 99% sensitivity and can rule out aneurysmal SAH. Lumbar puncture is recommended after 6 hours of symptom onset.

Patients with positive noncontrast CT results should undergo CT angiography unless the hemorrhage visible on CT is diffuse, in which case digital subtraction angiography provides better resolution.

Hospital Systems of Care

Most observational studies suggest that treatment of aneurysmal SAH at centers that treat more than 35 cases per year have superior outcomes. Stroke center designation is associated with lower in-hospital mortality for aneurysmal SAH.

Medical Treatment to Prevent Rebleeding

Blood pressure variability worsens outcomes in aneurysmal SAH and severe hypertension and relative hypotension should be avoided. Systolic blood pressure should be maintained at 160 mm Hg or less.

Reducing bleeding risk may not be beneficial once aneurysmal SAH is diagnosed. Treatment of bleeding with tranexamic acid does not reduce rebleeding or improve functional outcomes. Emergency anticoagulation reversal has not been studied in aneurysmal SAH, although it has been shown to be beneficial in other forms of intracerebral hemorrhage.

Aneurysm Repair

Aneurysm repair within the first 24 hours is recommended, unless the prognosis is very poor. Severe aneurysmal SAH, defined as a grade 4 or 5 on the Hunt and Hess or World Federation of Neurosurgical Societies scale, has a favorable outcome with treatment in 40% of patients. Although older patients tend to have worse outcomes after aneurysmal SAH, 42% of patients older than 65 years reach functional independence after treatment. Treatment is not recommended for patients who have partial loss of brainstem reflexes, lack of purposeful response to noxious stimuli, or imaging showing a large completed ischemic infarct or the global cerebral edema of anoxic brain injury.