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Subarachnoid Hemorrhage


What is subarachnoid hemorrhage?

Subarachnoid hemorrhage (SAH) is bleeding inside your brain from a ruptured (burst) blood vessel. Blood collects in the area underneath the membrane that surrounds your brain, called the subarachnoid space. SAH can occur when an abnormal blood vessel or an aneurysm bursts. An aneurysm is a bulging area of a blood vessel. A head injury can also cause a blood vessel to burst. SAH is a type of stroke that is life-threatening with or without treatment.

Subarachnoid Hemorrhage

What increases my risk for SAH?

Your risk increases if you have an aneurysm that has not burst. You may also be at risk if you or a family member have had SAH. Certain genetic diseases may also put you at risk for SAH. Your risk is also higher if you are a woman or are at least 50 years old. The following can also increase your risk:

  • Hypertension (high blood pressure)
  • Alcohol, cigarettes, or illegal drugs, such as cocaine or ecstacy

What are the signs and symptoms of SAH?

Rarely, you may have no signs or symptoms. You may have a sudden, severe headache that is worse than any headache you have ever had. This may be described as a thunderclap headache. It may happen within seconds and worsen within minutes. You may have a headache for days or weeks before the severe headache occurs. You may also have the following along with your moderate or severe headache:

  • Nausea or vomiting
  • Trouble walking
  • Dizziness, drowsiness, faintness, or another person cannot wake you
  • Double vision, eye pain in light, eyes pointing down and out, and drooping eyelids
  • Stiff neck that may be the only symptom
  • Numbness on one side of your body
  • Trouble talking, reading, or writing
  • Seizure

How is SAH diagnosed?

Your healthcare provider will examine you, and ask if you have a history of SAH or blood vessel problems. He may also ask if you have had a recent head injury. He will ask which medicines you are taking. He will ask if you smoke, abuse alcohol, or use illegal drugs, such as cocaine or ecstasy. You may also need the following:

  • CT scan: This test is also called a CAT scan. An x-ray and computer are used to take pictures of your skull and brain. A CT scan shows bleeding in the subarachnoid space.
  • Lumbar puncture: This procedure is also called a spinal tap. You may need this test along with a CT scan. Your healthcare provider will remove fluid from around your spinal cord. The fluid will be checked for blood.
  • Blood tests: Your blood may be tested to check your kidney and heart function. Your blood's ability to clot will also be tested.

Which medicines are used to treat SAH?

  • Antihypertensives: These reduce high blood pressure. This may help prevent the return of SAH. It is also used to prevent stroke and heart or kidney damage caused by SAH.
  • Calcium channel blockers: These help decrease the effects of brain damage that may occur after SAH.
  • Anticonvulsants: You may be given this medicine to help prevent seizures.
  • Antianxiety or sedative medicine: This medicine may be given to treat seizures.
  • Pain medicine: You may receive medicine to decrease or take away pain. Do not wait until the pain is severe before you take your medicine.

How is SAH treated?

  • Endovascular coils: Coils are placed inside your aneurysm to prevent it from filling with blood. This may prevent the aneurysm from bursting.
  • Surgical clipping: Your aneurysm is clipped off to help prevent it from bursting.
  • Therapy: A physical therapist and an occupational therapist may exercise your arms, legs, and hands. They may also teach you new ways to do things around the house. A speech therapist may work with you to help you talk or swallow.

What can I do to prevent SAH?

  • Control your blood pressure: Ask your healthcare provider about how to control your blood pressure.
  • Do not smoke tobacco or drink excess alcohol: This will help reduce the risk of return SAH.
  • Do not use illegal drugs: Illegal drugs may increase your risk of a SAH because they make your blood vessels contract and your blood pressure go up.
  • Eat more vegetables: Vegetables may help prevent strokes.

What are the risks of SAH?

  • SAH may cause blood vessels in your brain to narrow. This will slow oxygen from reaching your brain and may cause long-term brain damage. Blood clots may form inside your brain, and lead to a stroke. SAH may also cause blood clots to form in your body. These problems may be life-threatening. You may not fully recover after SAH. You may not sleep well, think clearly, or be able to work as you did before. You may also feel anxious, tired, or depressed. This may affect your relationships.
  • You may have more than one SAH, or your bleeding may return after treatment. You may need more than one surgery to treat other aneurysms that may occur. Radiation from repeated imaging tests may burn your skin or cause hair loss. Pressure in your brain may worsen if your healthcare provider cannot control your pain. This may worsen your SAH.

How can I tell if someone is having a stroke?

Know the F.A.S.T. test to recognize the signs of a stroke:

  • F = Face: Ask the person to smile. Drooping on one side of the mouth or face is a sign of a stroke.
  • A = Arms: Ask the person to raise both arms. One arm that slowly comes back down or cannot be raised is a sign of a stroke.
  • S = Speech: Ask the person to repeat a simple sentence that you say first. Speech that is slurred or sounds strange is a sign of a stroke.
  • T = Time: Call 911 if you see any of these signs. This is an emergency.

Where can I find more information?

  • National Stroke Association
    9707 E. Easter Lane
    Centennial , CO 80112
    Phone: 1- 800 - 787-6537
    Web Address:

When should I contact my healthcare provider?

  • You have neck stiffness that does not go away.
  • You have questions or concerns about your condition or care.

When should I seek immediate care or call 911?

  • You have any of the following signs of a stroke:
    • Numbness or drooping on one side of your face
    • Weakness in an arm or leg
    • Confusion or difficulty speaking
    • Dizziness, a severe headache, or vision loss
  • You have a mild to moderate headache that lasts a few days.
  • You have eye pain when you are in bright light, or you see double.
  • You have a seizure, or someone sees you lose consciousness.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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