Heat

You felt unwell, measured the temperature - that's right: the mercury column of the thermometer rose several degrees above the 37 degree mark. And what is the secret to conceal, the first thought, which appears in this case in many: take a febrifuge, in order to "knock down" the temperature. Do not hurry. Let's think, whether it is necessary to do it.

For millennia, nature has worked out a protective reaction, like a fever, the essence of which is precisely the increase in temperature. To respond in a similar way to any pathological impact from the outside may not be every living organism, but only standing on the high levels of the evolutionary ladder and only homoothermic. That is able to maintain a constant body temperature. The human body, endowed with the perfect mechanisms of thermoregulation, also belongs to homoyothermic. Thanks to these mechanisms, the temperature of our body fluctuates between 36-37 degrees in both heat and cold. And this is achieved through continuous balancing of two differently directed processes - heat production and heat transfer.

Heat in the body is released as a result of biochemical reactions of oxidation (combustion), where mainly fats and carbohydrates are used as a "fuel". When we are cold, the metabolic processes are intensified and more heat is released. In addition, various small and big "tricks" are used in the course. For example, the mechanisms of muscular tremor are included: individual muscle fibers reduce the mismatch, and all the biological energy of metabolic processes goes not to muscular work, but to the formation of heat.

But it is necessary to increase heat production, as soon as heat transfer processes are activated. The organism gets rid of the excess heat generated primarily by expanding the blood vessels, increasing sweating. The mechanisms of heat transfer are extremely mobile and play a leading role in regulating the constancy of body temperature.

But what happens to these well-established mechanisms in diseases accompanied by an increase in body temperature. Perhaps, excessive heat accumulates due to disruption of the thermoregulation apparatus? Not at all. Studies have shown that the increase in temperature is caused not by passive overheating. This is an active defensive reaction of the body, which is necessary for him in the fight against the disease.

As it turned out, the mechanism of this protective reaction is pyrogenic (heat-generating) substances. They are a part of various bacteria, as well as ours. Own cells and tissues. And when pathogenic bacteria enter the organism, or are destroyed under various pathological processes of its cells and tissues, pyrogenic substances are released and act on specific nerve endings embedded in tissues and organs. As a result, the characteristic changes begin in the work of the thermoregulatory center.

At first, heat transfer is sharply inhibited and heat production increases - the temperature rises. It can rise only one or two parts of a degree, or it can jump abruptly. Such an unequal temperature reaction is due, in particular, to those. That different organs are unequally equipped with nerve endings on which pyrogenic substances act. Experiments on animals have shown that the introduction of pyrogenic substance into the kidney causes a slight rise in temperature, and the same substance, introduced in the same amount in the articular bag, gives a high rise.

After the rise, the temperature stabilization phase begins, when the processes of heat production and heat transfer are balanced, and the mercury column of the thermometer keeps at a certain level for, say, 37.6 degrees. During this period, the body undergoes a series of physiological, immunological and biochemical shifts

A temperature increase of only one degree is usually accompanied by a heart rate increase of 8-10 beats per minute, while the amount of blood pumped by the heart in one contraction increases. The breathing becomes more rapid, the circulation of blood in the vessels of the brain, liver, kidneys and other organs increases. And this means that they are better supplied with oxygen and are more actively released from waste products.

The temperature rises - the activity of enzymes - biological catalysts, regulating and directing all the chemical reactions that occur in the body increases: the metabolism increases. Leukocytes and other cells that are able to capture and digest pathogenic microorganisms, their toxins and debris of deceased cells also become more active. And besides, the elevated temperature of the blood for some bacteria and viruses is a factor preventing their further reproduction. II Mechnikov wrote that "inflammation, leukocytosis and fever are hand in hand, going three times counteracting bacteria in case of their invasion of the body" .

Observations have shown that artificial suppression of fever complicates the course of some infectious processes, while a rise in temperature contributes to faster recovery in these cases. In this regard, at present specialists even resort to the artificial triggering of a feverish state in a number of diseases. So. Pharmacological preparations possessing pyrogenic properties are successfully used as an auxiliary means of treating rheumatic and nonspecific polyarthritis, eczema, furunculosis and other diseases.

Of course, one should not think that the fever has no negative consequences. After it, often come weakness, a breakdown. Chronic painful processes, particularly in the pharyngeal tonsils, can become aggravated, And besides, when the temperature rises very high, all the above-described qualities of a fever practically come to naught. Inhibits the activity of enzymes, which leads to a decrease in the intensity of metabolic processes and, consequently, the accumulation in the body of waste exchange products that have a damaging effect on the cells.

Violated the work of the nerve centers of regulation located in the brain, and this affects the functions of the heart, blood vessels, liver, kidneys, other vital organs. And it turns out that fever, at first a positive defensive reaction, now turns into a negative one.

The boundary, when negative manifestations of temperature begin to predominate over positive, usually passes at a mark of 38 degrees and above. But it can also be lower, for example, 37.8 degrees: everything depends on the individual characteristics of the organism. That is why it is right to find out what reactions prevail at the moment - positive or negative. - And decide whether it is necessary to lower the temperature or not. Can only the doctor. And if the temperature rises, do not rush to take antipyretics. Consult a doctor and he will prescribe medications that affect the underlying cause of the illness. And when the body with their help mobilizes its defenses and begins to conquer the disease, the temperature will begin to decrease. The fever will enter its third stage: heat transfer will begin to prevail over heat production, as one of the most energy-intensive processes - sweating - will turn on. This stage is perhaps the most responsible in the whole feverish reaction. Its absence indicates deep violations of thermoregulation and can lead to overheating. And overheating is dangerous for the patient and with a temperature of 38 degrees, not to mention a higher one. When a person begins to sweat profusely and heat emission prevails over heat production, high temperature is not so terrible. The appearance of sweating in a febrile patient indicates that. That the crisis has passed, the matter is on the amendment.