In the past few days, the continuous high temperature in most parts of the country has started the "sauna day" mode. People have lamented that such a hot destiny is caused by the air conditioner! Heat stroke, also known as severe heatstroke, is a very dangerous emergency with a v

▍The author of this article: Wang Xiaohuan, Doctor of Medicine, Fudan University

What do you want to say is the hottest thing recently?

Of course it’s the weather!

In the past few days, most parts of the country have been experiencing high temperatures.

The "sauna day" mode has been turned on.

People have lamented that such a hot day is caused by the air conditioner!

In fact, "heat to death" is really not just a casual saying

Long-term exposure to high temperatures is very dangerous ↓↓

Picture source: News screenshot

" Heat stroke " is an important keyword

It is understood that under high temperatures Many of the deaths

were caused by "heat stroke"

So, what is heat stroke? What is the relationship between

and heatstroke? Is

really as scary as the news says?

Today, let’s find out together!

What is heat stroke?

Heat stroke, also known as severe heat stroke, is a very dangerous emergency. The mortality rate is very high, reaching 40% to 50%. For people over 50 years old, the mortality rate even reaches about 70%.

The human body has a body temperature regulation center. Under normal circumstances, it will adjust the balance of heat production and heat dissipation in the body to maintain the body temperature at around 37°C.

But in some cases, this balance of heat production and heat dissipation will be broken, causing heat to accumulate in the body, causing heat stroke.

Generally speaking, human body heat dissipation mainly relies on radiation, evaporation and a small amount of convection and conduction.

When the ambient temperature is higher than the skin temperature, the human body can only rely on evaporation and sweating to remove heat . However, when the temperature is too high, the heat dissipation capacity will decrease (this phenomenon is called sweat failure), and heat accumulation will occur in the body. This causes the organs, especially the brain, to "go out of control" and lead to heat stroke.

Heat stroke is caused by the rapid accumulation of heat in the body. Patients with often experience symptoms such as local muscle spasm, high fever, no sweating, dry mouth, coma, difficulty breathing, and even respiratory failure. is the most fatal form of heat stroke.

In addition to individual factors, the incidence of heat stroke is closely related to three factors: high temperature, high humidity and a closed, windless environment.

Heat stroke is generally mild, with the body temperature often exceeding 38°C, accompanied by facial flushing, profuse sweating, burning skin, nausea and vomiting, or cold limbs, pale face, decreased blood pressure, and rapid pulse.

The difference between heat stroke and heatstroke is that it manifests as high fever (rapid rise in body temperature), often no sweating, and even coma and shock.

Heat stroke is usually accompanied by a body temperature as high as 40℃ or above. What changes will happen to the body at this time?

What happens when the body temperature reaches 40°C?

As we all know, the highest scale of a thermometer reaches 42°C. Will people be "burned to death" if the temperature exceeds this temperature?

When the human body temperature is 37°C, the body's heat production and heat dissipation are relatively balanced, and the body's functions are the most stable. When body temperature rises, there is also an adjustment mechanism, but when it exceeds a certain limit, it will lead to organ intolerance and organ failure.

For example, for the heart, when the body temperature exceeds 37°C and gradually rises to over 40°C, the cardiac output will increase exponentially, and the oxygen consumption will also increase by about 40%.

But when the body temperature reaches 42°C, cardiac output and oxygen consumption will suddenly decrease, and myocardial necrosis will occur.

This is caused by ultrahigh temperature exceeding the tissue tolerance limit, causing organ failure. Obviously, this can be life-threatening.

Normally, if the fever reaches 39°C, you will almost doubt your life. What disease can cause the fever to reach 42°C? The answer is heat cramps, heat exhaustion, and heat stroke. Heat stroke is the most serious.

Which groups should pay special attention to heat stroke?

Heat stroke is most likely to occur in the elderly, children, pregnant women or people with underlying diseases (such as cardiovascular and cerebrovascular diseases, obesity).

The body functions of the elderly decline, and cardiac output cannot be adjusted in high temperature environments, leading to heat stroke due to circulatory disorders. Children often suffer from heatstroke due to poor sweat response.

In addition, people with colds, fever, gastroenteritis diarrhea and hypokalemia are also prone to heatstroke.

If heat stroke occurs, how should we provide correct treatment?

Immediately transfer the patient to a cool and ventilated place, then let him lie down, physically cool him , replenish water (salt water is best), etc. At the same time, call 120 for emergency treatment in time, and the treatment should not stop during the emergency route.

How to prevent heat stroke?

Outdoors, the main objective factors that affect people's heat stroke are: daily average temperature, relative humidity and maximum temperature.

If the daily average temperature is >30°C and the relative humidity is >73%, the probability of heat stroke will show a significant upward trend. If the maximum temperature is ≥37°C, the number of people suffering from heat stroke will increase dramatically. If you meet two of the conditions before going out, you should pay attention.

In addition, it should also be noted that the alternation of hot and cold can also easily lead to heat stroke. The body cannot adapt to it all of a sudden, and there may also be body temperature regulation disorders, water and electrolyte balance imbalances, and heat stroke neurological disorders. For example, if you are sweating profusely and suddenly the air conditioner blows...

For people who need to work outside for a long time or whose working environment is stuffy and airtight, it is best to prepare some salt water, ice cubes, etc. in advance.

In addition, when people suffer from heat stroke, they usually show signs of heat stroke, which generally include symptoms such as headache, dizziness, thirst, excessive sweating, and weakness of the limbs.

If it is moved to a cool and ventilated place in time, physically cooled down and replenished with water (salt water is best), it can recover in a short time.

Pay attention to getting enough sleep and drinking plenty of water. When there is a high temperature warning, go out as little as possible.

Finally, I would like to emphasize that

when the symptoms of heat stroke are severe, you must not be careless

it can really kill you!

In addition, pay attention to the rhythm when cooling down and replenishing water.

When performing physical cooling, it must be done quickly

When replenishing water, it should be appropriate. Too fast is not good.

This article was first published in "Science China (ID: Science_China)", author Wang Xiaohuan, copyright belongs to All rights reserved.

Editor of this article: Ren Xuan

Department Director: Yang Xiaoming

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