Our body is a complex system of unresolved chemical equations. In inanimate nature, everything tends to a state with the lowest entropy, wants to freeze or move evenly rectilinearly … Only life forces the atoms that make up the body to dance, moving from one cell to another, breaking into parts and uniting into new groups, giving away and taking away foreign electrons. Only death stops this falconry. Sometimes death comes as a result of the fact that the external environment takes away energy that must be spent on intra- and intercellular melteshenie. Then they say that the person froze to death.
But it is very difficult to quickly evacuate all the energy from the human body under ordinary terrestrial conditions. Even the Antarctic cold does not kill right away. Cooling down, the human body struggles with the environment, mobilizes all resources, then begins to save the leftovers, and surrenders only at the very end.
Up to 32 ° С
First, the blood vessels narrow, limiting the influx of hot blood to not very vital limbs: not to fat, enough for the heart and brain. This phenomenon is called a vasoconstrict. Then the hairs on the body rise: the body tries to make a heat-insulating fur coat out of our poor human materials.
32 – 35 ° С
The person starts to tremble: these muscle fibers are uncontrollably shortened in an attempt to warm the body. If you do not freeze almost to death, you are hardly aware of such a tremor: these are real convulsions, and not an easy twitching in a frosty evening. Trembling will continue until the muscle cells do not run out of glucose.
There is a shiver stopped, and a warm shelter has not yet been found, the body is in grave danger. Spending on cramps all the energy reserves, and now they are not enough even to support the activity of the brain – the most valuable organ. Passed through these stages, people talk about the confusion of thoughts, hallucinations, deafness. Vasoconstriction is replaced by a desperate attempt of the body to warm the cold hands and feet: the blood, still concentrated around the internal organs of the chest and abdomen, as well as the brain, suddenly rushes through the dilated vessels to the extremities, and the person becomes … hot. A clouded mind can not take advantage of this sudden warming for salvation; Instead, the freezing often begins to undress and therefore die faster.
30.5 – 29.5
In this state, the body, like a mobile phone, which sits battery, goes into an energy-saving mode: a person falls asleep, and then plunges into a coma. The heart rhythm is broken, then the heart stops. From oxygen starvation, the brain dies. But in the cold – and this is important! – not only the processes of vital activity go slowly, but also the processes of dying. This allows resuscitation physicians to pull dying from the cold from the cold in conditions in which, at normal temperature, a person would not be saved.
Sometimes this slow dying from hypothermia is used in medicine – true, only in the most extreme cases, for heart and brain operations. The patient’s body is cooled to 19-21 degrees. At this temperature, cells consume less oxygen; this allows you to turn off the heart or a large aneurysm from the bloodstream – a pathological dilatation of the blood vessel. And so that the patient does not tremble on the operating table, he is immersed in a deep anesthesia beforehand. They are cooled in different ways: they are surrounded by ice bags, blown in cold air, most often – immersed in cold water (8-10 ° C), and sometimes cools the blood outside the body with the help of tubes and special air or liquid refrigerators.
Deep hypothermia gives doctors a few extra minutes to perform an operation that is impossible at normal body temperature. When the operation is completed, the body is returned to its normal temperature. Especially easy to carry such manipulations of babies.