Subarachnoid hemorrhage

Diagnosis

To diagnose a subarachnoid hemorrhage, you may need the following tests:

• CT scan. This imaging test is very effective at detecting bleeding in the brain. But it may not detect bleeding if you have a low red blood cell count or if there is a small amount of bleeding. Your healthcare professional may inject a contrast dye to view your blood vessels in greater detail, known as a CT angiogram.
• MRI. This imaging test also can detect bleeding in the brain. An MRI scan may show signs of a subarachnoid hemorrhage in rare cases when it's not detected by a CT scan. Your healthcare professional might inject a dye into a blood vessel to view the arteries and veins in greater detail, known as an MR angiogram.
• Cerebral angiography. You may have a cerebral angiography to get more-detailed images. Angiography also may be done if a subarachnoid hemorrhage is suspected, but the cause isn't clear or doesn't appear on other imaging. A long, thin tube known as a catheter is inserted into an artery and threaded to your brain. Dye is injected into the blood vessels of your brain to make them visible under X-ray imaging. Sometimes a cerebral angiogram does not show an aneurysm. If this happens, you may have a second angiogram if your healthcare professional thinks an aneurysm is likely.

For some people with an aneurysm that caused a subarachnoid hemorrhage, the bleeding may not appear on initial imaging. If this happens, you may need a lumbar puncture. During this procedure, a needle is inserted into the lower back. A small amount of the fluid that surrounds the brain and spinal cord, known as cerebrospinal fluid, is removed. The fluid is then studied to look for blood, which may mean that you have a subarachnoid hemorrhage.

Treatment

Treatment of a subarachnoid hemorrhage focuses on stabilizing the condition. Your healthcare team checks your breathing, blood pressure and blood flow.

If you have a burst aneurysm, you're treated for it and your healthcare team works to prevent complications.

To treat a ruptured brain aneurysm, your healthcare professional might recommend:

• Surgery. The surgeon makes an incision in the scalp and locates the brain aneurysm. A metal clip is placed on the aneurysm to stop the blood flow to it.
• Endovascular embolization. The surgeon inserts a catheter into an artery and threads it to your brain. Detachable platinum coils are guided through the catheter and placed in the aneurysm. The coils reduce blood flow into the aneurysm and cause the blood to clot. Different types of coils have been developed to treat aneurysms.
• Other endovascular treatments. Certain aneurysms can be treated with endovascular embolization that uses newer technology. These newer techniques include stent-assisted or balloon-assisted coiling or devices that divert blood flow.

Treating the ruptured aneurysm quickly can help prevent bleeding from happening again.

It's also important to prevent other complications. A subarachnoid hemorrhage may lead to low salts such as sodium in the blood. It also may cause high or low blood sugar. Your healthcare team monitors these levels and treats them if needed.

There also may be poor blood flow to the brain. A common complication of a subarachnoid hemorrhage due to a burst aneurysm is a constriction and narrowing of the blood vessels in the brain, known as vasospasm. This can cause a stroke if blood flow decreases to a certain level. A stroke may be avoided by raising blood pressure or by widening blood vessels in the brain with medicines. The medicine nimodipine (Nymalize) also can lower the risk of vasospasm.

Another common complication is a buildup of fluid in cavities within the brain, known as hydrocephalus. This can be treated with drains inserted in the head or lower back.

Sometimes, procedures need to be repeated. After your initial treatment, follow-up appointments with your healthcare team are important to watch for any changes. You also may need physical, occupational and speech therapies.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Preparing for your appointment

A subarachnoid hemorrhage is a medical emergency, so it is likely to be treated in the emergency department. Doctors who specialize in the brain and nervous system may be involved in your care. These specialists may include neurologists, neurosurgeons and neuroradiologists.

What you can do

To make the most of your time with your healthcare team, be ready with the following information. Make a list of:

• Your symptoms, including any that seem unrelated to the reason for seeking medical care.
• Key personal information, including major stresses, recent life changes and family medical history.
• All medicines, vitamins or other supplements you take, including the doses.
• Questions to ask your healthcare team.

For subarachnoid hemorrhage, some basic questions to ask your healthcare professional include:

• What's likely causing my symptoms?
• Other than the most likely cause, what are other possible causes for my symptoms?
• What tests do I need?
• Is my condition likely short-term or long-lasting?
• What's the best course of action?
• What are the alternatives to the primary approach you're suggesting?
• I have these other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?
• Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your healthcare professional is likely to ask you several questions, such as:

• When did your symptoms begin?
• Have your symptoms been constant, or do they come and go?
• How serious are your symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, appears to worsen your symptoms?