What is a subarachnoid hemorrhage?

Hemorrhage means heavy bleeding. The space between the brain and the tissue that covers the brain is called the subarachnoid space. So this kind of hemorrhage is bleeding in that space just outside the brain.

When blood spills into this small space, it builds up and presses on the brain. This often causes sudden and severe head pain. Other symptoms sometimes include nausea and vomiting, neck pain, or vision problems. Some people pass out or have a seizure. But the most common symptom is what many people describe as "the worst headache of my life."

This hemorrhage is a type of stroke. Quick treatment is needed to prevent brain damage and death.

The problems caused by a subarachnoid hemorrhage depend on what part of the brain was affected and how much damage it caused. For example, there may be problems with movement, senses, speech, memory, thinking, or emotions. Stroke rehabilitation, which includes training and therapy, can help with recovery.

What causes it?

Most subarachnoid hemorrhages are caused when a brain aneurysm bursts. An aneurysm (say "ANN-yuh-riz-um") is a bulging, weak area in the wall of an artery that supplies blood to the brain.

It can be hard to know what exactly caused a brain aneurysm and why it burst. Many things can raise the risk of this, such as smoking, high blood pressure, and a family history of aneurysms.

This type of hemorrhage can also be caused by many other things, including a head injury.

How is it treated?

The goal of treatment is to prevent brain damage, more bleeding, and other serious problems. You will likely be in the hospital's intensive care unit, where your medical team can keep a close watch on you. They will work to control your blood pressure, manage pain, and watch for symptoms of brain damage.

You may have more tests to find out for sure that an aneurysm caused the bleeding. If you have an aneurysm, you may have a procedure or surgery to repair it. This can help prevent another bleeding episode.

Treatments to repair an aneurysm include:

• Clipping. The doctor makes cuts (incisions) in your scalp and through the bone of your skull. Then the doctor places a tiny metal clip over the weak part of the blood vessel. This stops the flow of blood.
• Coiling. The doctor makes a cut in your groin or wrist. Then the doctor moves a small plastic tube through the cut and into a blood vessel. The tube is called a catheter. Using X-rays, the doctor gently guides the catheter through the blood vessel up to the brain aneurysm. Then the doctor uses a tool to fill up the aneurysm with tiny wire coils or block the opening. This keeps blood from getting back into the aneurysm.

You will need treatment even if your symptoms go away. This is because there is a good chance that the area will bleed again.