What is stroke?
Stroke, also called brain attack, occurs when blood flow to the brain is disrupted. Disruption in blood flow is caused when either a blood clot blocks one of the vital blood vessels in the brain (ischemic stroke), or when a blood vessel in the brain bursts, spilling blood into surrounding tissues (hemorrhagic stroke).
The brain needs a constant supply of oxygen and nutrients in order to function. Even a brief interruption in blood supply can cause problems. Brain cells begin to die after just a few minutes without blood or oxygen. The area of dead cells in tissues is called an infarct. Due to both the physical and chemical changes that occur in the brain with stroke, damage can continue to occur for several days. This is called a stroke-in-evolution.
A loss of brain function occurs with brain cell death. This may include impaired ability with movement, speech, thinking and memory, bowel and bladder, eating, emotional control, and other vital body functions. Recovery from stroke and the specific ability affected depends on the size and location of the stroke. A small stroke may result in problems such as weakness in an arm or leg. Larger strokes may cause paralysis (inability to move part of the body), loss of speech, or even death.
Stroke is an emergency and should be treated as such. The greatest chance for recovery from stroke occurs when emergency treatment is started immediately. At Methodist Brain and Spine, we say “TIME IS BRAIN” – the faster a stroke is treated, the more brain function is preserved.
Stroke is the fourth leading cause of death, ranking behind diseases of the heart, lungs, and all forms of cancer. According to the NSA, strokes kill more than 137,000 Americans each year.
What are the different types of stroke?
Strokes can be classified into 2 main categories:
- -87% are ischemic strokes. These strokes are caused by blockage of an artery.
- -13% are hemorrhagic strokes. These strokes caused by bleeding.
What is an ischemic stroke?
An ischemic stroke occurs when a blood vessel that supplies the brain becomes blocked or “clogged” and impairs blood flow to part of the brain. The brain cells and tissues begin to die within minutes from lack of oxygen and nutrients. The area of tissue death is called an infarct. About 87% of strokes fall into this category.
What is a hemorrhagic stroke?
Hemorrhagic strokes occur when a blood vessel that supplies the brain ruptures and bleeds. When an artery bleeds into the brain, brain cells and tissues do not receive oxygen and nutrients. In addition, pressure builds up in surrounding tissues and irritation and swelling occur. About 13% of strokes are caused by hemorrhage.
What are the most common symptoms of stroke?
The following are the most common symptoms of stroke. However, each individual may experience symptoms differently. If any of these symptoms are present, call 911 (or your local ambulance service) immediately. Treatment is most effective when started immediately. Symptoms may be sudden and include:
- Weakness or numbness of the face, arm, or leg, especially on one side of the body
- Confusion or difficulty speaking or understanding
- Problems with vision such as dimness or loss of vision in one or both eyes
- Dizziness or problems with balance or coordination
- Problems with movement or walking
- Severe headaches with no other known cause
- Loss of consciousness or seizure
All of the above warning signs may not occur with each stroke. Do not ignore any of the warning signs, even if they go away — take action immediately. The symptoms of stroke may resemble other medical conditions or problems. Always consult your doctor for a diagnosis.
What are some other symptoms of stroke?
Other, less common, symptoms of stroke may include the following:
- Sudden nausea, vomiting, or fever not caused by a viral illness
- Brief loss or change of consciousness such as fainting, confusion, seizures, or coma
- Transient ischemic attack (TIA), or “mini-stroke”
A TIA can cause many of the same symptoms as a stroke, but TIA symptoms are transient and last for a few minutes or up to 24 hours. Call for medical help immediately if you suspect a person is having a TIA, as it may be a warning sign that a stroke is about to occur. Not all strokes, however, are preceded by TIAs.
Remember, it is critical to act quickly if you suspect that you or someone you know is experiencing signs of stroke. If any of the following symptoms occur,
F – face drooping
A – arm weakness
S – speech difficulty
T – time to call 911!
…act FAST and call 911. Remember, “TIME IS BRAIN”.
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