Subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is bleeding into the subarachnoid space. Clinical approach differs by etiology — see the appropriate page below:

• Aneurysmal subarachnoid hemorrhage — spontaneous/non-traumatic SAH (most commonly ruptured cerebral aneurysm)
• Traumatic subarachnoid hemorrhage — SAH due to blunt or penetrating head trauma