The human body is a wonderful and complicated device. This lets us do all kinds of awesome things, like seeing, thinking about, or tasting ice cream. But its complexity also leaves it vulnerable to damage. One of the ways that damage can manifest itself is as a stroke, a leading cause of mortality and disability across the world.

Although its effects are significant, a stroke is actually a very small event. So let’s take a look at exactly what they are, why they happen, and why they’re so bad for us.

Bad blockage

In essence, a stroke takes place when blood can’t properly reach part of the brain. One example would be blood vessels becoming clogged — typically due to a blood clot, but not necessarily. This cuts off the blood supply to a part of the brain, meaning neurons there don’t receive nutrients or, much worse, oxygen. Affected areas of the brain will thus quickly stop functioning, leading to a loss of control over the body parts or processes the area governs. Unless addressed quickly, strokes can lead to permanent damage in the affected areas, including tissue death.

Both internal and external factors can help cause a stroke. Sustained high acceleration rates (typically measured in “g”-s, the “acceleration of gravity”) can lead to a stroke, as can high blood pressure. They are also known as cerebrovascular accidents (‘CVA’) or less commonly as ‘brain attacks’.

In very broad lines, there are two types of strokes: ischemic, where blood flow is cut to a part of the brain by a clot, for example, and hemorrhagic, where blood doesn’t reach the areas it’s supposed to due to bleeding within the brain. Either way, it’s not good news.

What to look out for

Please keep in mind that strokes are not a harmless event. They are a medical emergency in the full sense of the phrase, and a fast reaction can help save the patient’s life. After symptoms set in, there’s a window of around 3 to 4-and-a-half hours for doctors to resolve the issue. Even so, brain tissue degrades very rapidly when deprived of oxygen, and a quick response is meant to prevent extensive damage but can’t avoid all damage. Typically, strokes lead to long-lasting brain damage that can seriously impair a person’s ability to function. The effects of such an event can range from (relatively) mild, such as general numbness in an area, to quite serious, such as losing the ability to speak or walk.

But, as I mentioned, a FAST response can help you spot the early warning signs of a stroke and help protect your loved ones. The National Stroke Association (NSA) defines FAST as:

• Face: watch for irregularities in the movements of facial muscles. A droopy face or sagging smile can be an important clue that something is not quite right in the brain.
• Arms: ask the person in question to raise both arms. Strokes affect brain activity, which can cascade into effects on muscle groups. If one or both of the individual’s arms move or drift downwards against their wishes, a stroke might be the cause.
• Speech: impaired muscle control can also reveal itself in slurry, messy speech. Ask the person in question to repeat a simple phrase and determine if they are able to do so.
• Time: as we’ve said before, the secret of success here is moving FAST. If a person has any, several, or all of these symptoms, call emergency services (i.e. 911 in the U.S.) immediately. It is quite literally a matter of life or death.

Treatment generally consists of anti-clotting medication (thrombolytics), but will obviously differ based on the cause of the stroke. Giving anti-clotting medication to someone with a hemorrhagic CVA is a surefire way to kill them. For such strokes, blood transfusions are used to stabilize the patient and, if needed, doctors will intervene to remove some of the fluid build-up and thus lower pressure on the rest of the brain. In severe cases, doctors can also attempt a mechanical thrombectomy — a direct intervention to remove the blood clot from the vessel it lodged in. This procedure isn’t available in all hospitals and care units as it requires specialized equipment; it’s usually employed up to 24 hours after symptoms onset at most.

The 3 to 4 and a half-hour time frame is used as a kind of gold standard for saving a CVA patient’s life. But the harsh truth is that once a stroke happens, some type of permanent damage to the brain (and thus, permanent symptoms) is usually unavoidable. However, it’s not a guarantee, and doing nothing will almost always be fatal. If you notice any of these signs in others or yourself, drop everything and call emergency services for help.

Exactly what happens after the stroke, how quick the recovery is, and what long-term effects it has are highly dependent upon where in the brain this stroke happened. The symptoms are caused by a lack of oxygen for neurons to feed and not the actual clot or hemorrhage that leads to it, and thus typically arise suddenly and affect one side of the body. Typical signs one is happening to you include numbness, weakness, tingling sensations, and loss of or changes in vision. Other common symptoms include difficulty speaking or understanding speech, vertigo, issues with maintaining balance or consciousness.

Strokes are sometimes accompanied by headaches, nausea, vomiting, especially for hemorrhagic strokes.

What causes them?

As a rule of thumb, keeping your circulatory system healthy should help ward off strokes — in other words, an active lifestyle and cardio help here. Keep tabs on your weight, follow a healthy diet as far as you can, exercise regularly, don’t smoke, and monitor your blood pressure to be as safe as possible. People who have high blood pressure or cholesterol levels, those suffering from diabetes, and smokers are particularly at risk of developing a stroke. Individuals who have underlying heart rhythm disturbances are also at risk, especially those with atrial fibrillation.

But no matter why it happens, you now know how to spot the signs of a stroke and how to act fast to keep everyone safe.