were affected mainly older people whose exposure to extreme cold caused a decrease in body temperature and the development of hypothermia, which can be lethal.
What is the effect it can have the cold in our body?
An obvious danger is the freezing of extremities such as fingers, cheeks, nose and ears.
if stopped freezing time can be reversed, otherwise it may result in loss of tissue. Body temperature
But one of the most drastic of cold on the human body is hypothermia.
It occurs when the normal temperature of man-about-37 ° C decreases and in severe cases leads to chill uncontrolled. loss of control in the hands, feet and legs and sometimes swelling and bruising of the skin.
But the brain also slows down, that is, the thoughts are more lethargic, speech difficulties and the person becomes irrational.
Dr Kevin Fong is an expert in space medicine at the University of London. He knows better than anyone what it is to endure extreme cold or extreme heat. In space there is rarely an intermediate temperature.
According to the expert, humans operate with a very limited range of temperature.
"We are totally useless with a body temperature of two or three degrees above or below 37 º C", tells BBC scientist.
"We cook with two degrees, we 'turn off' with two degrees less."
When body temperature drops to between 32 º C and 35 º C the heart begins to slow its pace. If the temperature drops again, things start to become serious.
At the cellular level can alter the propagation of electrical impulses that control heart, increasing the risk of a heart attack.
mechanisms to face the cold
If the normal temperature falls below 30 º C the heart may stop altogether.
The agency has a range of mechanisms developed to combat the loss heat.
tremors, for example, are an attempt by the body to generate heat by means of small muscle movements around vital organs.
These are caused by a brain region that responds to small fluctuations in the normal body temperature.
But, as Fong, in humans the most basic defense is behavior.
"The way to avoid death by freezing in a ski resort is putting on a coat before leaving. We used to do the right thing when we are cold," said the BBC in conversation with the expert.
Fong is participating in a project that is being used a freezing technique to 'kill and revive' people who are undergoing heart surgery.
"I had to sit in a pool of water at a temperature of 12 º C," says the researcher.
"The hardest thing is to sit and do nothing to combat the cold. Every fiber of your body is screaming at you to do something to warm you up, like swimming."
And the cold, he adds, is a double-edged sword.
Extreme cold can cause cardiac arrest, but also preserves brain function.
So in extremely cold conditions a person may appear dead but it's still alive. Fond
quoted an ancient medical dictum, "is dead only when it is hot and lifeless." (BBC)
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