First Aid

Potential Emergency Situations and Conditions

Stroke / Brain Attack

What is stroke?

Stroke, also called a brain attack, happens when the arteries leading to the brain are blocked or rupture. When the brain does not receive the needed oxygen supply, the brain cells begin to die. A stroke can cause paralysis, inability to talk, inability to understand, and other conditions brought on by brain damage. Strokes kill nearly 150,000 Americans each year and are the leading cause of adult disability.

What are the different types of strokes?

There are four main types of stroke:

cerebral thrombosis - caused by blood clots
cerebral embolism - caused by blood clots
cerebral hemorrhages - caused by hemorrhages
subarachnoid hemorrhages - caused by hemorrhages

Cerebral thrombosis and cerebral embolism are the most common types of brain attacks, accounting for about 70-80 percent of all strokes.

cerebral thrombosis:
is the most common type of brain attack.
occurs when a blood clot (thrombus) forms and blocks blood flow in an artery leading to the brain -- arteries primarily affected by atherosclerosis are more susceptible to blood clots.
most often occurs at night or first thing in the morning when blood pressure is low.
is often preceded by a transient ischemic attack (TIA) or "mini-stroke."
cerebral embolism:
occurs when a wandering clot (embolus) or some other particle forms in a blood vessel away from the brain -- usually in the heart. The clot then travels and lodges in an artery leading to the brain or in the brain.

About 15 percent of strokes occur in people with atrial fibrillation, a cardiac disorder in which the upper chambers of the heart do not beat effectively.

cerebral hemorrhages - occur when a defective artery in the brain bursts.
subarachnoid hemorrhages - occur when a blood vessel on the surface of the brain ruptures and bleeds into the space between the brain and the skull.

Problems resulting from stroke:

Problems resulting from stroke may include:

temporary or permanent impairment including weakness on one side of the body
problems with balance and/or coordination
difficulties with speech and memory
problems with vision or reading
trouble swallowing
pain
numbness
depression and/or sudden outbursts of emotions
problems with being unaware of the effects of the stroke
problems concentrating, thinking, learning, or making decisions
loss of energy and/or chronic fatigue

What are the risk factors for stroke?

high blood pressure
diabetes
smoking
high cholesterol level
heart disease
transient ischemic attacks (TIAs)

Be sure to discuss these risk factors with your physician and identify things that you can do to avoid having a stroke.

What are the symptoms of a stroke?

Stroke happens suddenly and may be prevented by immediate response to warning signs. Warning signs and symptoms may include:

sudden weakness or numbness of the face, arm, or leg on one side of the body
sudden difficulties with speech and understanding what others are saying
sudden problems with vision -- dimness or loss of vision, particularly in one eye
sudden dizziness
sudden problems with walking

Another warning sign of stroke is called transient ischemic attack (TIA), also called a "mini-stroke." A TIA can cause many of the same symptoms as a stroke, but TIA symptoms generally only last for a few minutes. Call for immediate medical assistance if you suspect a person is experiencing a transient ischemic attack, as TIAs may lead to stroke. Also call for immediate medical assistance is you suspect a person is experiencing a stroke.

This page was last updated on: January 25, 2008.

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