What Is Stroke?
Stroke is also called a cerebral vascular accident. Stroke occurs when a blood vessel in the brain is blocked (blood flow in the brain stops) or ruptures. It is an emergency. Blood carries a constant supply of oxygen and nutrition that the brain requires. When the blood flow in the brain is interrupted, a part of the brain does not receive enough oxygen and nutrition. This causes damage as the brain cells begin to die within a few minutes. The amount of brain cell death depends on the severity and duration of the blockage or rupture. The functions controlled by the areas with dead or damaged brain cells may be lost or limited. This may include losing the ability to:
Move, walk, or use the hands.
Speak or think.
Control the bowel, bladder, and other body functions.
Delaying treatment increases the risk of permanent brain damage, disability, or death.
There are two types of stroke:
An ischemic stroke is the most common type. It occurs when a blood vessel is blocked. A blood clot or a buildup of fatty deposits (arteriosclerosis) in the blood vessels that supply the brain can lead to blocked blood vessels. Ischemic stroke accounts for 87% of all strokes. The most common cause of ischemic stroke is fatty deposits lining the blood vessel walls.
A hemorrhagic stroke occurs when a weakened blood vessel leaks or ruptures. When a blood vessel bursts in the brain, blood builds up and damages surrounding brain tissue. The most common cause of hemorrhagic stroke is high blood pressure. Hemorrhagic stroke also can occur in people with a tangle of abnormal vessels connecting arteries and veins in the brain. This tangle is called brain arteriovenous malformation. AVM may disrupt blood flow and result in bleeding in the brain.
Both types of stroke damage brain cells. The damage causes symptoms that start to show in the parts of the body and functions controlled by those brain cells.
How Does It Feel?
A stroke is a serious medical condition that requires emergency care. It is important to know the signs of a stroke and get help quickly if you or someone you are with shows any signs of stroke. Medical treatment is most effective when started immediately. If you have one or more of the following symptoms, call 911 right away for an ambulance:
Sudden numbness or weakness of the face, arm, or leg, especially on one side of the body.
Sudden confusion or trouble speaking or understanding.
Sudden trouble seeing in one or both eyes.
Sudden trouble moving or walking.
Sudden dizziness or loss of balance or coordination.
Sudden, severe headache with no known cause.
Sudden nausea or vomiting not caused by infection or viral illness.
Loss or change of consciousness, confusion, or seizures with no known cause.
Emergency treatment with a clot-buster drug called t-PA can help reduce or even eliminate problems from stroke. The drug must be given within three hours of when symptoms start.