Subarachnoid hemorrhage

A subarachnoid hemorrhage (SAH) is a type of brain hemorrhage that often occurs between the brain and the membrane that protects it. A SAH is a medical emergency.

If you suspect you have a subarachnoid hemorrhage, call 911 immediately or get to your nearest emergency department.

What is a subarachnoid hemorrhage?

The brain has three layers of protective membranes called meninges. The outermost layer is the dura mater, the middle layer is the arachnoid, and the layer closest to the brain is the pia mater. A subarachnoid hemorrhage occurs when bleeding happens in the space below the arachnoid layer.

Symptoms of a subarachnoid hemorrhage

Most often, the hallmark symptom of a subarachnoid hemorrhage is experiencing what feels like the worst headache you've ever had. Other symptoms may include:

• Confusion, drowsiness or seizures
• Fainting or loss of consciousness
• Nausea and vomiting
• Neck stiffness and pain
• Seizures
• Vision problems
• Weakness or paralysis

Recognizing the symptoms of a subarachnoid hemorrhage and getting a prompt diagnosis and treatment is vital to improving recovery outcomes.

Diagnosing a subarachnoid hemorrhage

To diagnose a subarachnoid hemorrhage, your doctor will first ask about your symptoms and review your medical history.

Your doctor will work to locate the source of the bleeding by using imaging testing such as a CT scan or an MRI. They may also order one of the following advanced diagnostic tests for a subarachnoid hemorrhage:

• Angiogram: During an angiogram, a catheter is inserted into an artery and threaded through the circulatory system up to the brain. A dye is then injected through the catheter. This dye makes blood flow easier to see on X-rays.
• Computed tomography angiography (CTA): During a CTA test, dye is injected directly into the bloodstream. This dye makes it easy to see the arteries in your brain on a CT scan.
• Lumbar puncture: Also known as a spinal tap, a lumbar puncture is another way to make a brain bleed diagnosis.

Treatment for a subarachnoid hemorrhage

Once diagnosed, the goal is to stop the bleeding, prevent further complications and promote healing. Your treatment plan might involve:

• Bed rest: Rest allows your brain to recover from the trauma.
• Surgery: Clipping or coiling the ruptured aneurysm or repairing tangled blood vessels, known as arteriovenous malformations (AVMs), to prevent future bleeds.
• Medications: Your doctor may give you medications to control blood pressure, prevent blood clots and reduce brain swelling.

Risk factors for a subarachnoid hemorrhage

The most common risk factor of a subarachnoid hemorrhage is a brain aneurysm, which is a balloon in your blood vessel that eventually bursts.

Other underlying risk factors of a subarachnoid hemorrhage include:

• Arteriovenous malformations (AVMs): Tangled webs of blood vessels, prone to leaks.
• Traumatic brain injury: A physical blow can damage brain tissues and blood vessels.
• High blood pressure: A constant strain on your arteries, increasing rupture risk.
• Blood thinners: While beneficial for some people, they can exacerbate bleeds if not carefully monitored. Let your doctor know if you are taking blood thinner medications.

In some cases, there may not be an underlying cause of a subarachnoid hemorrhage.

Recovering from a subarachnoid hemorrhage

The prognosis for subarachnoid hemorrhage depends on the severity of the bleeding and the timing of your treatment. Some people recover fully with no long-term effects, while others may experience permanent brain damage.

Your doctor may recommend:

• Physical therapy: To regain lost muscle function and coordination.
• Speech therapy: To relearn language skills if affected by the bleed.
• Occupational therapy: To adapt to any cognitive or emotional changes.
• Support groups: To connect you with others who understand the challenges you face.

Preventing a subarachnoid hemorrhage

While predicting a subarachnoid hemorrhage can be tricky, taking preventive measures can help prevent them. These include:

• Get regularly screened for aneurysms if you have a family history or other risk factors.
• Make healthy lifestyle changes, such as adjusting your diet or getting more exercise to improve blood flow.
• Manage your blood pressure.
• Quit smoking, limit alcohol intake and maintain a healthy weight.