Definition

A subarachnoid hemorrhage (SAH) is bleeding in the space that surrounds the brain. This can raise pressure around the brain. SAH can be deadly.

Causes

SAH may be caused by:

• Head trauma
• Broken cerebral aneurysms and other unusual blood vessel problems

Risk Factors

SAH is more common in people who are aged 50 years and older. Other things that may raise the risk are:

• Having family members who have had aneurysms
• Having certain genetic syndromes, such as Ehlers-Danlos syndrome
• High blood pressure
• Smoking
• Alcohol use disorder
• Substance use disorder
• Use of combined oral contraceptives (in women)

Symptoms

Problems may be:

• Sudden, severe headache
• Nausea and vomiting
• Stiff neck
• Light sensitivity
• Loss of consciousness
• Seizures

Diagnosis

The doctor will ask about your symptoms and health history. A physical exam will be done. This may be enough to suspect the diagnosis.

Pictures may be taken of the brain and the structures around it. This can be done with:

• CT scan
• MRI scan

The fluid in the spine may need to be tested. This can be done with a lumbar puncture.

CT Scan of the Head Copyright © Nucleus Medical Media, Inc.

Treatment

Emergency care is needed right away. The goals of treatment are to:

• Stop the bleeding
• Limit harm to the brain
• Reduce the risk of another SAH

Options are:

• Surgery to stop an aneurysm from bleeding
• Medicines to help blood flow to the brain, to ease pain, and to treat other symptoms, such as seizures

Rehabilitation will be needed when a person is stable. This may include speech, physical, and occupational therapy.

Prevention

SAH cannot always be prevented. To lower the risk:

• Manage high blood pressure
• Avoid using tobacco
• Limit alcohol
• Eat a healthful diet