Intracranial hemorrhage
Epidural hematoma
Subarachnoid hemorrhage
Etiology
- Traumatic SAH: traumatic brain injury
- Nontraumatic (spontaneous) SAH
- Ruptured intracranial aneurysms
- Most commonly occur in the circle of Willis
- Berry aneurysms account for approx. 80% of cases of nontraumatic SAH.
- Also known as Saccular aneurysm because of the shape
- Round, saccular shape
- Most common type of cerebral aneurysm
- Typically occur at vessel junctions in the circle of Willis, most commonly between the anterior communicating artery and anterior cerebral artery
- Account for ∼ 80% of cases of nontraumatic subarachnoid hemorrhage
- Also known as Saccular aneurysm because of the shape
- Ruptured arteriovenous malformations (AVM)
- Ruptured intracranial aneurysms
| Feature | Charcot-Bouchard Microaneurysms | Saccular (Berry) Aneurysms |
|---|---|---|
| Associated Conditions | Hypertension | ADPKD, Ehlers-Danlos syndrome, hypertension |
| Location | Basal ganglia Cerebellum Thalamus Pons |
Circle of Willis |
| Size | <1 mm | Variable, 2-25 mm |
| Result of Rupture | Intracerebral hemorrhage | Subarachnoid hemorrhage |
| Symptoms of Rupture | Progressive neurologic deficits Headache may follow |
Sudden severe headache Focal neurologic deficits uncommon |
- Saccular: This term means "resembling a sac." Saccular aneurysms are outpouchings or bulges on one side of a blood vessel wall.
- Berry: The "berry" description refers to the characteristic round shape of these aneurysms. They look like a berry connected to the main artery.
Diagnosis
CT head without contrast
- Defining feature: blood in subarachnoid space (hyperdense) with variable extension and location
Treatment
Initial management
- Prevention of rebleeding
- Anticoagulant reversal
- Management of blood pressure and cerebral perfusion pressure
- Target SBP < 160 mm Hg
- Other neuroprotective measures
- Start ICP management (e.g., elevate head 30°, IV mannitol, short-term controlled hyperventilation).
Treatment of aneurysmal SAH
- Intracranial aneurysm repair
- Endovascular coiling
- Microsurgical clipping
- Prevention of vasospasm and delayed cerebral ischemia
- Administer oral nimodipine
- Only administer nimodipine orally or via enteral tube; Parenteral administration is associated with significant adverse effects (e.g., severe hypotension and cardiac arrest).
- Treatment of hydrocephalus: may include an external ventricular drain (EVD), lumbar drainage, or permanent ventriculoperitoneal shunt
- Administer oral nimodipine
Warning
Generally avoid nitrates for blood pressure control in brain injury, as they may elevate ICP. Consider alternative agents (e.g., titratable nicardipine or labetalol).
Complications
Vasospasm
- Occurs in approx. 30% of patients with SAH
- Pathophysiology
- Impaired CSF reabsorption from the arachnoid villi → nonobstructive (communicating) hydrocephalus → ↑ intracranial pressure → ↓ cerebral perfusion pressure → ischemia
- Release of clotting factors and vasoactive substances → diffuse vasospasm of cerebral vessels → ischemia
- Impaired CSF reabsorption from the arachnoid villi → nonobstructive (communicating) hydrocephalus → ↑ intracranial pressure → ↓ cerebral perfusion pressure → ischemia
- Can lead to ischemic stroke
- Most common in patients with nontraumatic SAH due to a ruptured aneurysm
- Usually occurs between 3–10 days after SAH
- Oral nimodipine should be given after subarachnoid hemorrhage to prevent vasospasm