What is a stroke? Blood flow is cut off to brain cells, which begin to die. Most strokes can be prevented. About a third of survivors recover completely.
What is a stroke?
If blood flow is cut off to an area of the brain, the cells there lose the oxygen they need and begin to die. The end result depends on which cells die. About a third of people who have a stroke recover completely. For instance, if you have a very small stroke, you might only experience temporary weakness in one arm or leg.
What are the signs of a stroke?
- Sudden numbness or weakness in your face, arm, or leg, especially on one side of your body
- Sudden confusion, trouble speaking, or understanding
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance, or coordination
- Sudden severe and unexplained headache
Have someone call “911” if you have any of these symptoms or see them in someone else. Speed is essential: for each minute blood is blocked in the brain, a person loses about 1.9 million neurons. Emergency medication works best within three hours.
What are the risk factors of stroke?
- Your chance of stroke begins to increase at blood pressure readings higher than 120/80 millimeters of mercury (mm Hg).
- A total cholesterol level above 200 milligrams per deciliter is also a problem.
- Overweight and physically inactive people are more at risk of stroke.
- Heavy or binge drinking, using cocaine or methamphetamines, and smoking are also risk factors.
- Diabetes, sleep apnea, heart disease, and a family history of stroke can all contribute.
Strokes are more common after the age of 55. But they have risen steadily among Americans under the age of 45 since 1995, probably triggered by rising rates of obesity, diabetes, and high blood pressure.
Only 15 percent of all strokes are hemorrhagic — when blood spills into the brain after a blood vessel bursts and leaks. The usual cause is high blood pressure and or simply age. Some people have a genetic vulnerability that leads to bleeding vessels in the brain. A bleeding disorder, head injury, or blood thinners can also lead to a hemorrhagic stroke.
Strokes most commonly occur when a blood clot or fragment of plaque travels to the brain from somewhere else, usually the heart, and gets stuck in a blood vessel. This is called an ischemic stroke. The cause is sometimes an irregular heartbeat.
Sometimes a blood clot forms inside one of the arteries feeding blood to the brain, causing a “thrombotic” stroke. The cause may be in the large or small vessels of the arteries. High cholesterol levels and atherosclerosis can trigger this type of stroke. Two types of blood clots can cause thrombotic stroke: large vessel thrombosis and small vessel disease.
Transient ischemic attack
Blood flow to the brain can stop very briefly, causing symptoms of a transient ischemic attack (or TIA) for less than 24 hours. You’re not likely to have lasting damage, but you should take action to prevent a future stroke.
Hospitals once could provide only blood thinning medicine, the sooner the better. Now there are surgical interventions possible during the stroke and afterwards, better ways to help patients restore their functioning. For example, doctors can thread a catheter through an artery in the groin and up to the brain. The catheter ends with a wire-cage device called a stent retriever. It opens and grabs large blood clots.
Doctors could also use special tubes to suction out a clot.
These procedures work best within 6 hours of the first acute stroke symptoms, but can sometimes be helpful up to 24 hours later.
May 25, 2020
Janet O’Dell, RN