What is a stroke?

Also called a “brain attack,” a stroke occurs when oxygen-rich blood does not flow properly to a part of the brain. When brain cells are deprived of oxygen, they begin to die within minutes. Stroke may also develop as a result of bleeding in the brain, which can damage and/or kill brain cells.

A stroke is considered a medical emergency that requires immediate treatment. Without prompt medical intervention, a stroke can cause lasting damage to the brain, disability or death.

Two types of stroke

There are two types of stroke: ischemic and hemorrhagic.

Ischemic stroke results from blocked or disrupted blood flow to the brain, often caused by blood clots. Ischemic stroke is the most common type of stroke.

Hemorrhagic stroke occurs if an artery in the brain breaks open and bleeds, or bleeds for any reason. The pressure from this bleeding causes damage to the brain cells. The bleeding that leads to hemorrhagic stroke may be caused by high blood pressure or an aneurysm, which is a balloon-like growth in an artery that can stretch and rupture.

Another type of stroke similar to an ischemic stroke is called a transient ischemic attack, which occurs when blood flow to a part of the brain is blocked for a short amount of time. Because the interruption in blood flow is minor and briefer than the other types of stroke, the damage to the brain cells is not lasting. Similar to an ischemic stroke, a transient ischemic attack is also frequently caused by blood clots. Transient ischemic attacks also require emergency care, because they greatly elevate the risk for having a stroke.

Symptoms

There are several symptoms of a stroke, including:

difficulty speaking or understanding what others are saying;
confusion or disorientation;
severe, sudden headache, sometimes combined with dizziness or vomiting;
numbness or paralysis of the face, arms or legs; inability to raise both arms over the head at the same time without one or both arms dropping;
difficulty seeing out of one or both eyes, or seeing double;
drooping of one side of the mouth; and
difficulty walking

The “FAST” approach

A good way to remember the signs of a stroke in yourself or a loved one is to use the “FAST” approach:

Face: Is there paralysis or drooping of the face?
Arms: Can you/your loved one lift both arms without one or both arms drifting downward?
Speech: Can the person repeat a simple sentence or phrase without slurring their speech?
Time: Check the time when calling emergency services so you know what time symptoms began.

Additional information can be found at these websites:

www.nhlbi.nih.gov/health/health-topics/topics/stroke

www.mayoclinic.org/diseases-conditions/stroke/home/ovc-20117264