Hypothermia is the loss of body heat. Causes, types, symptoms. Human hypothermia: everything you need to know about hypothermia

Under the general hypothermia of the body is meant a pathological condition (hypothermia), in which, under the influence of adverse cold environmental factors, the thermoregulation system is disturbed and the body temperature drops below the minimum threshold (34 ° C) necessary to maintain the functioning of vital body systems.

Body temperature is one of the main constants and its maintenance in a certain and rather narrow range is the most important condition for the adequate functioning of the organs and systems of the human body. Even slight deviations from the norm can cause a violation with the development of cold / heat illness. Maintaining body temperature in the individual norm is carried out through a complex physiological system of regulation of heat balance, regulated by the processes of heat production and heat transfer.

Heat balance in the body

In the human body, there are nucleus”, including all internal organs and the brain, and the external part - "shell", formed by muscles, subcutaneous tissue and skin. For the share shells» accounts for almost half of the body weight, and lowering its temperature even by a few degrees causes significant changes in the heat content of the body.

The temperature of different sections of the shell is not the same and can vary significantly. At the same time, the level of core temperature fluctuates within insignificant limits (daytime temperature is higher than nighttime). Under cold exposure, the tissue mass of the core and shell changes in the direction of compression of the core tissues.

Temperature constancy is maintained by the balance of heat production and heat transfer processes. At the same time, the thermal conductivity of living tissue is a constant value and is not regulated by anything. The temperature of the body surface is maintained due to heat transfer from the tissue mass of the core to the surface of the skin, which occurs by conduction (contact thermal conductivity) and convection (heat transfer by blood). The body of a healthy person is able to maintain an internal temperature within the range of 36.0 - 37.5 ° C due to thermoregulation and biological processes of homeostasis.

Heat generation is a by-product of metabolic processes (primary heat) and physical (muscular) work (secondary heat). The level of heat generation is determined by the intensity of the main metabolism, " specific dynamic action» food entering the body, muscle activity, metabolic rate in various tissues. The contribution to the total heat production of the body of different organs and tissues varies significantly.

The most significant mechanism of heat generation is contractile thermogenesis , that is, heat is generated by skeletal muscles during their tonic contraction (800 - 1000 kcal / day). An additional mechanism of heat generation is non-contractile thermogenesis, which is based on the metabolic activity (oxidation) of adipose tissue under the influence of norepinephrine , the production of which increases under the influence of cold on the body.

In general, there are several leading mechanisms in the process of heat generation:

• Increase in basal metabolism (the higher the metabolism, the more heat the body produces). The rate of metabolic processes is regulated by direct action through the autonomic nervous system.
• Increased muscle activity (one of the body's reactions to cold is chills and shivering - involuntary high-frequency / low-amplitude contraction of muscle fibers, which increases heat generation by 150-200%).
• SPDP (specific dynamic action of food) - the release of an additional amount of energy in the process of processing nutritional ingredients, which is included in the process of heat generation.
• Increase in circulating blood volume. An increase in the intensity of basal metabolism requires an increase in the amount of blood. Accordingly, it is removed from the depot and enters the circulatory system, accelerating the transfer of heat from the core to the surface of the body.
• Acceleration of metabolism in the liver system (as a result of chemical reactions in the liver, 350 - 500 kcal of heat / day is produced).
• Increase in heart rate (the heart in the process of functioning releases 70-90 kcal / day of heat, and when the heart rate accelerates, this figure increases to 150 kcal / day).
• Acceleration of the functions of other organs (muscles of the diaphragm, kidneys, brain and other organs produce up to 500 kcal/day during the acceleration of functioning).

There is a constant exchange of heat between the human body and the environment, which is carried out in several ways:

• conducting (conduction);
• radiation (radiation);
• evaporation of water from the surface of the body and convection (transfer with the flow of the medium).

Obviously, the constant maintenance of temperature in a narrow range is possible only if the processes of heat generation and heat transfer are equal.

thermoregulation

Thermoregulation is carried out by a highly differentiated and multicomponent system, which includes deep and superficial thermosensitive receptors. The main organs in which deep receptors are concentrated are the midbrain and medulla oblongata, the reticular formation and other structures of the brain stem, and centers of sympathetic innervation. Surface temperature-sensitive receptors, the number of which is approximately 250 thousand, are located throughout the thickness of the mucous membranes and skin, and about 200 thousand more receptors are located in various internal organs and tissues - kidneys, liver, gallbladder, pleura and others.

Such a wide spread and abundance of thermosensitive receptors is explained by the fact that temperature homeostasis is regulated not by the temperature of any one part of the body, but by the average body temperature. All receptors respond to fluctuations in the temperature of the environment in the range of 10-41 degrees, at the exit from which the functioning of the receptors is disturbed. So, when the temperature of the skin drops to + 12 ° C, the surface skin receptors are blocked and cease to perform their function. With a decrease in the temperature of the external environment, the frequency of impulses sent to the brain increases, and with an increase, it decreases.

Mechanisms of thermoregulation during hypothermia

Mechanisms of heat generation

With hypothermia, due to a decrease in body and blood temperature, the activity of cold receptor fibers sharply increases, which contributes to the stimulation of the nuclei of the posterior hypothalamus, which is responsible for activating the mechanisms of heat generation. That is, heat generation reactions are activated, and heat loss processes are suspended by turning on adaptive mechanisms: immediate - through the autonomic nervous system and delayed - with the participation of the endocrine system, realized through the mechanisms of physical, chemical thermoregulation:

• Chemical thermoregulation - strengthening of tissue metabolism (acceleration of the oxidation of proteins, fats and carbohydrates) with the acceleration of heat production. Increased levels of adrenal/thyroid hormones that speed up basal metabolism and heat production.
• Physical thermoregulation - centralization of blood circulation (reduction of the lumen of the blood vessels of the skin - arterioles and small arteries and a decrease in blood flow to the surface of the body), which reduces heat transfer to the external environment. The reaction of the skin muscles, which reduces heat loss through evaporation.
• Adaptive response in the form of increased physical activity.
• Extrapyramidal skeletal muscle stimulation and muscle tremors.

Heat loss reduction mechanisms

At low temperatures, the adaptive reaction of the body is the maximum reduction in heat loss. To accomplish this task, the hypothalamus, as in the previous case, acts by influencing the autonomic nervous system.

These mechanisms are:

• Centralization of blood circulation . It is carried out by reducing the flow of blood to the surface of the body with the redirection of its circulation along the " core", since the rate of heat loss depends directly on the volume of blood passing through the" shell". So, at a temperature of 15 0 C, the blood flow in the hand is reduced by 6 times. With further cooling, spasm of peripheral tissue vessels may develop. Along with a positive effect, a sharp decrease in blood flow, combined with low temperature, causes frostbite.
• Decreased open body area. The rate of heat loss depends not only on temperature, but also on the area of ​​contact of the body with the external environment. Accordingly, in order to change the contact area, the body takes a more economical (closed) position in terms of energy costs (subconsciously pulls the knees to the chest, curling up into a ball).
• The reaction of the skin muscles. This mechanism occurs quite often and is realized by the tension of the muscles that raise the hair follicles, which is commonly called " goose bumps". As a result, the undercoat and cellularity of the coat increase, contributing to an increase in the layer of warm air around the body. Theoretically, this improves thermal insulation, since air is a poor conductor of heat, but the practical value of this rudimentary mechanism is not great.
• Reduction of heat loss by evaporation . When water evaporates from the surface of the body, heat is also lost. Evaporation of 1 ml of water leads to a loss of 0.58 kcal of heat, since on average a person loses 1400 - 1800 ml of moisture through evaporation (sweat, with breathing), then when hypothermia stops sweating and slows down breathing, heat loss decreases by 12 - 15%.
• Increase in subcutaneous fat . This mechanism is realized only when a person lives for a long time at low temperatures and consists in an increase in the layer of adipose tissue and its more uniform distribution over the surface of the body.

Disorders of life in unintentional hypothermia

With a general cooling of the body, the heat balance is disturbed due to the fact that heat transfer exceeds heat production. Cooling the body leads to a decrease in the rate of metabolic processes, metabolic disorders and the development of hypothermic pathology. During hypothermia, the temperature of the body's core decreases below optimal values. In the process of general cooling of the body, phases of compensation and decompensation are distinguished.

Pathogenesis, stages of development

In the development of cold sickness, several vicious circles of pathogenesis are distinguished. The main ones are:

• metabolic vicious circle . With a decrease in body temperature, there is a sharp slowdown in metabolic processes (depending on the temperature of the core by 2-3 times), which is accompanied by a decrease in heat generation. As a result of a decrease in body temperature, metabolism is additionally suppressed, that is, " metabolic vicious circle».
• vascular vicious circle . The decrease in body temperature during body cooling in the range of 30-33 0 C is accompanied by the phenomenon of expansion of arterial vessels of the mucous membranes, subcutaneous tissue and skin. This, in turn, causes an influx of warm blood from the core organs to the skin, which accelerates the body's heat transfer with the development of a pathological circle (a decrease in body temperature causes additional vasodilation, an influx of warm blood and heat loss).
• neuromuscular vicious circle . In the body, in the process of lowering the temperature, there is a decrease in the excitability of the nerve centers, in particular, the centers that control muscle contraction, which turns off one of the most important mechanisms from the heat production system - contractile thermogenesis . That is, the body temperature drops even more, which leads to further suppression of neuromuscular excitability and, accordingly, further suppression of the thermogenesis process.

The increase in cooling of the body causes an increase in inhibitory processes in the nerve centers of the cortical and subcortical structures, which leads to, in extreme cases, ending. With an increase in the intensity of the cold factor, complete freezing and death from hypothermia occurs. As a rule, a person dies as a result of the cessation of cardiac activity and respiratory arrest. Death occurs when the rectal body temperature drops below 25-20 0 C.

Stages of development

In the process of general hypothermia of the body, phases of compensation and decompensation are distinguished.

Compensation phase

This stage is characterized by a set of standard reactions:

• Reducing the level of heat and mass transfer due to narrowing of the blood vessels of the subcutaneous tissue and skin of the body (the blood supply to the skin decreases on average by 1.5-2.0 times when the core temperature drops by 1°C below normal).
• Increased heart rate by 20-22%.
• The volume of pulmonary ventilation increases.
• Increasing selection catecholamines .
• Contractile thermogenesis increases (due to active movements).
• Non-contractile thermal production increases (due to the acceleration of oxidative processes).

Along with an increase in heat generation, there is a limitation of heat transfer due to the regulation of vascular tone (decrease in tissue blood flow in the surface tissues of the body).

Decompensation phase

This stage is characterized by:

• Decreased metabolic rate.
• A sharp depletion of the cells of the structures of the central nervous system and glands of the endocrine system.
• Decrease in the tone of the arterial system, decrease in capillary pressure and efficiency of the cardiovascular system.
• Loss of electrolytes with the development of severe disturbances in water and electrolyte balance.
• and development.
• Plethora of internal organs with the development of pulmonary edema, hemorrhage and necrosis in the gastric mucosa, necrobiotic changes in the mucous membrane of the renal tubules, a decrease in glomerular filtration and renal blood flow, wrinkling of adrenal cells.
• With an increase in hypothermia, cerebral blood flow decreases, cerebrospinal fluid pressure drops, coronal blood flow decreases, cardiac output decreases, and heart rhythm is disturbed. At 28–30°C, consciousness is lost, and at 14–20°C, the bioelectrical activity of the brain begins to disappear.

Classification, stages of hypothermia

Causes of development and factors contributing to the disease

Primary hypothermia - a common phenomenon, especially in a mild form. Predominant among young males in an urban environment. Often the victims of hypothermia are people who are not sufficiently prepared to stay outdoors in the autumn-winter period due to various circumstances or who live in insufficiently heated rooms.

Extreme cases are various kinds of catastrophes (falling into an avalanche, cold water environment), extreme sports, travel in difficult weather conditions, loss of the ability to move, disorientation in the area (in the forest).

A sharp increase in heat loss

The main factors affecting the likelihood of hypothermia are:

• ambient temperature;
• air humidity;
• wind power.

Weather

The most significant is the ambient temperature. There is a direct relationship between the ambient temperature and the rate of heat loss.

Atmospheric humidity also directly affects the rate of heat loss. As humidity increases, the rate of heat loss increases. The highest heat loss rate is observed when a person enters the aquatic environment, which is a good heat conductor compared to air.

Wind is the unidirectional movement of air. When the wind increases, the air around the body is quickly replaced by colder air. So, when the wind moves at 5 m/s, the heat transfer increases twice, at 10 - four times. In addition, the wind dehydrates exposed areas of the body.

Of particular danger is the combined effect of all three factors. High humidity does not pose a serious threat. However, getting your clothes wet when exposed to cold rain or immersion in cold water greatly increases the risk of hypothermia. Many people underestimate the risk of hypothermia and often ask if it is possible to get sick from hypothermia while being in positive temperatures. In the presence of high humidity and strong wind, it is possible to supercool even at plus / zero temperatures.

Quality and seasonality of clothing and footwear

Clothing/shoes can significantly reduce the rate of heat loss from the body. The determining factor is the material of the clothing, the ability to retain heat, as well as the correct size of the item / shoe. In the cold season, the most preferred material is natural wool / fur, which has a high cellularity, in which there is a lot of air that prevents the body from losing heat. Their artificial counterparts follow. The main disadvantage of synthetic clothing is their ability to accumulate moisture under clothing, which increases the rate of heat loss, contributing to faster hypothermia.

Shoes and clothing must be sized carefully, as tight clothing reduces the amount of warm air. The same applies to shoes, the thickness of the sole of which must be at least 1 cm, and the shoes must not squeeze the limbs. The same applies to clothes / shoes that are oversized and do not fit snugly enough to the contour of the body, forming gaps through which warm air escapes.

Factors leading to hypothermia

Most often, hypothermia occurs due to:

• Underestimation of weather conditions.
• Reassessment of their physical abilities.
• Non-seasonal use or prolonged exposure to wet clothes.
• Inability to assess their condition and self-diagnose hypothermia in the early stages.

Increased heat loss due to intoxication

Heat loss occurs due to vasodilation caused by intoxication (usually alcohol) or medication. The minimum amount of an alcohol-containing drink required to expand the blood vessels of the subcutaneous fat and skin is 15-30 ml (in terms of pure alcohol), and for the elderly - half as much. At the same time, drinking alcohol creates an illusory sensation of warming the body.

The catch is that this sensation is caused by the flow of warm blood from the core of the body to the cold skin, which quickly cools, quickly returns to the core, causing a sharp decrease in body temperature. In fact, alcohol, by expanding blood vessels, prevents the mechanism of centralization of blood circulation, which has been developed in the process of evolution and is aimed at preserving human life when it enters low temperatures. Therefore, if a person in a state of intoxication often falls asleep on the street, even at an ambient temperature close to zero, most often it ends with frostbite, pneumonia, and even death.

Violations of thermoregulation

Violations of the processes of thermoregulation are most often due to the presence of a number of diseases and pathological conditions. Hypothermia is promoted by:

• Heart failure . It is characterized by a decrease in blood flow velocity, which increases the duration of blood stay in the peripheral part of the body, and contributes to its stronger cooling. In the presence of edema, which is characteristic of heart failure, blood circulation in the extremities worsens even more and leads to even greater cooling of the blood.
• . Thyroid hormones are involved in the regulation of various biological reactions, including supporting reactions accompanied by the release of heat. Accordingly, with a decrease in the level of thyroxin, the body temperature decreases. At the same time, the greater the deficiency of hormones, the lower the body temperature, and such patients quickly become supercooled in the cold.
• cachexia . Lack of body weight and cachexia as an extreme option, regardless of the causes that caused such conditions, are accompanied by a decrease in muscle tissue and thinning of subcutaneous fat, which, in fact, is a natural thermal insulator in the body. With its lack, the rate of loss of body temperature increases dramatically. In addition, in the absence of adipose tissue, the ability to produce heat is lost due to the oxidation of fats, the efficiency of which for the production of heat is several times higher than that of any other tissue. The same applies to the muscles that generate most of the heat energy. With a decrease in muscle mass, the level of heat production decreases proportionally. In general, being underweight increases the risk of hypothermia.
• . Adrenal cortex insufficiency is manifested, that is, a lack of blood content, and androsterone . With a deficiency of aldosterone and cortisol, blood pressure decreases, which leads to a slowdown in blood flow and, accordingly, greater cooling of the blood on the surface of the body and less heat. The lack of cortisol reduces the rate of basal metabolism (the rate of chemical reactions), which are accompanied by the release of energy. Accordingly, less heat is produced in the "core", which, in combination with a stronger cooling of the blood, contributes to a high risk of developing hypothermia, even when a person is in conditions of moderately low temperatures.
• . The mechanism of hypothermia during blood loss is simple - blood is a heat carrier from the core to the surface of the body and, accordingly, blood loss is directly proportional to heat loss. At the same time, a person tolerates chronic/slow bleeding much better than acute bleeding, since compensatory organisms do not work in acute significant blood loss. Blood loss in the amount of 300 - 500 ml is tolerated by the body almost imperceptibly, 500 to 700 ml is accompanied by nausea, dizziness, thirst and the need to take a horizontal position. Up to this level of blood loss, the body compensates for its loss due to the flow of blood from the depot. Blood loss of more than 1 liter, especially at low temperatures, is dangerous with a high risk of losing consciousness for 1-3 hours and turning off all thermoregulation mechanisms. That is, the rate of drop in the body temperature of a person who has lost consciousness is similar to the rate of drop in the temperature of a corpse, which is 1 0 C / hour (with standard air humidity and no wind). Thus, the first degree of hypothermia will come after 3, the second - 6-7, and the third - 9-12 hours.
• Traumatic brain injury . The danger lies in the high risk of loss of consciousness with the shutdown of all protective mechanisms.

The lack of heat production also occurs in elderly people, premature babies suffering from acute / chronic diseases.

Symptoms of hypothermia

Symptoms of hypothermia vary depending on the stage of hypothermia:

• Light degree (35-32.2 0 С): adynamia and lethargy, severe drowsiness are characteristic. Complaints of fatigue, chills, weakness, thirst, sometimes dizziness and headache. Speech is slow, scanned (separate pronunciation of words). Consciousness is preserved in most cases. The skin is pale, the presence of goosebumps syndrome. The pulse slows down to 60-65 / minute, the pressure is moderately increased (140/100 mm Hg).
• Average degree (32.2-29 0 C): consciousness is depressed, severe drowsiness, pulse of weak filling decreases to 35-50 beats / min, articular movements are constrained, the look is meaningless, the skin is pale, bluish, to the touch - cold breathing is superficial, rare 10 -12/minute), the pressure is reduced (up to 80-90/40-50 mm Hg).
• Severe degree (below 29 0 C): consciousness is absent, the tongue is often bitten, the reaction of the pupils to light is absent or weakly expressed, the muscles are sharply tense, including the abdominal muscles and chewing muscles are bent, there may be convulsions, there are signs of hypothermia in the form of stiffness (inability to unbend limbs), the skin is cold to the touch, pale, cyanotic. The scrotum is reduced, the testicles are tightened. The pulse is arrhythmic, rare (about 30/minute), hardly palpable, blood pressure is not determined. Involuntary urination. It is important to understand that the clinical picture of severe hypothermia, due to the high potential reversibility of freezing processes, does not predetermine a fatal outcome.

Analyzes and diagnostics

The diagnosis of hypothermia is established by the doctor on the basis of an external examination, anamnesis (according to the persons who found the victim) and the results of measuring body temperature. At the same time, only the indicators of rectal temperature, made by special electronic thermometers with a fine scale calibration in the range of low temperatures, are reliable. Sometimes it is practiced to measure the temperature of a fresh portion of urine.

It should be borne in mind that the absence of breathing / heartbeat and a decrease in the base body temperature below critical values ​​are not evidence of death. Death is declared only after all measures for warming have been carried out and there are no signs of life against this background.

To confirm the diagnosis, an ECG is performed, on which the presence of an Osborne wave is a characteristic feature, as well as other laboratory tests and instrumental studies: general blood / urine tests, determination of glucose, electrolytes, urea, creatinine, and blood pH, pulsometry, measurement of blood pressure, determination hourly diuresis, if necessary - ultrasound, chest x-ray.

It should be noted that attempts to independently determine " When is hypothermia considered mild?"and determining the possibility of getting out of it yourself are unacceptable, since the symptoms of hypothermia often vary in different people and are often atypical and erased. Moreover, most people rarely realize that they already have symptoms of general hypothermia of the body and believe that they are all right, forgetting that the processes of hypothermia occur imperceptibly.

Treatment

The state of hypothermia is an emergency, and the further condition of the patient and the prognosis depend on how correctly the first aid is provided for hypothermia.

What should be done in case of hypothermia?

With mild hypothermia, a person is conscious, there is shivering, the temperature is 35-32 0. shiver reflex - this is a mechanism of heat production, which increases it by 5 times if a person is in a stationary state. Trembling stops when energy reserves in the body are depleted. As long as the victim does not experience circulatory arrest, all actions focus on preventing further heat loss and rewarming.

After calling an ambulance on the spot, first aid consists of:

• Dacha warm and sweet, but not alcohol-containing drink, which depresses the vital centers of the brain. Warm sugary drinks provide carbohydrates, but they don't provide the body's needed warmth.
• Gradual warming outdoor procedures (various methods of insulation and the use of heat sources). It is impossible to warm the victim too quickly because of the possible decrease in internal temperature when cooled blood enters from the periphery after the expansion of peripheral vessels.
• In the active exercise of the victims - this is possible only with a mild degree. If a person can move, it is impossible to limit him in his movements, since in active movement he warms up faster and subsequently there will be no adverse outcomes.
• In more severe cases, on the contrary, it is very important to carefully shift the victim and prevent sudden movements due to the readiness of the myocardium for fibrillation. In an ambulance, they must be transported on a stretcher to warn venous return , dangerous cardiac arrest (collapse "from rescue").

If we consider the methods of warming, they can be divided into passive (insulation and protection from further heat loss), active surface (thermal warming procedures) and active internal (in a hospital) warming. The most important is gradual warming.

Passive warming methods

Warming activities at the pre-hospital stage in the street are the simplest passive methods of warming: the creation of a vapor barrier (if the patient is wet), a heat-insulating and windproof layer. As a heat-insulating layer, water-tight bubble wrap can be used. Removing wet clothes certainly creates more comfortable conditions, but if done in cold and windy conditions, it will cause even more cooling.

If a vapor barrier is created, then changing clothes to dry is not necessary. The top layer of the shelter must be windproof. When in nature, you need to place the victim in a sleeping bag, and when wet clothes, create a waterproof barrier (the same bubble wrap or polyethylene). If possible, use a heat source (hot water bottles).

If conditions permit:

• remove wet clothes and shoes;
• change into dry clothes;
• carefully cover with a blanket with your head;
• warm the victim.

Passive rewarming is effective for mild hypothermia, when the ability to generate heat (muscle tremors) has not been lost. Sometimes isolation from the cold is enough and the victim is gradually warmed by his own thermogenesis.

Active external warming

Active external (superficial) warming at the prehospital stage is carried out by applying heat to the skin. Bottles with warm water, heating pads, water bags should be applied to the chest area, head, large vessels (groin, neck, axillary region). Direct skin contact should be avoided as there is a risk of burns. If warming is carried out at home, then radiators, convectors, heated mattresses, electric sheets and blankets are used.

You can not completely immerse a person in a warm bath, as rapid heating leads to a pronounced vasodilation, which is associated with a risk of development. However, warming by immersion in 42–45°C water for the hands, feet, and lower legs can be used and has a good effect. This method allows you to increase body temperature by 9 0 per hour. . It is impossible to warm frostbitten limbs until the temperature is more than 34 0 С.

If, with a mild degree, only warming is enough and the temperature returns to normal on its own, then with moderate and severe, medical care is needed in a hospital. Active warming during hypothermia of the III degree (a person is unconscious, but signs of life are determined) and IV degree (cardiac arrest) is especially important during long journeys. Rescue teams are equipped with warm air blankets. Patients with IV degree hypothermia during transportation to the center are better to maintain their original temperature. Heat is supplied but dosed to maintain this temperature level. The task is to prevent further cooling and prevent warming.

Grade III has a high risk ventricular fibrillation and cardiac arrest , therefore, such patients are hospitalized in clinics equipped with artificial blood circulation devices and apparatus for extracorporeal membrane oxygenation .

With an extremely severe IV degree, there is a high probability of death. Circulatory arrest and lack of breathing is an indication for resuscitation and it is desirable to adjust the supply of warm oxygen through the mask. Cardiopulmonary resuscitation is started immediately and continues on the way to hospitalization, where extracorporeal life support will be performed. Termination of resuscitation can be fatal for the victim.

High-quality resuscitation is the key to a good prognosis. The retraction of the tongue is eliminated, do endotracheal intubation to supply oxygen after suction of mucus from the respiratory tract. Perform closed heart massage . Under difficult evacuation conditions, manual resuscitation can be difficult, so mechanical devices are used. They provide 50% of the required level of blood flow to the brain and a sufficient supply of oxygen to important organs. With ventricular fibrillation in conditions of hypothermia defibrillation perform inefficiently. One or two attempts are made, and if there is no effect, the procedure is postponed until the temperature rises to 30 ° C and above.

The warming rate at the prehospital stage should not be more than 1 0 C per hour, since there is a risk of developing " afterdrop» - expansion of peripheral vessels and a repeated drop in internal temperature due to the inflow of cooled blood from the periphery. This enhances the violations: increases the risk of pressure reduction, development arrhythmias , heart failure and cardiac arrest .

Active internal warming

Active internal (central) warming in a hospital helps to normalize the heart rhythm and correct coagulation system disorders, sometimes even without the use of drug treatment. Internal heating is provided by:

• Inhalation of warm (40–45°C) oxygen through a mask or tube. This procedure reduces heat transfer during breathing and increases the rate of warming by 1-1.50 per hour.
• Intravenous infusions of warm solutions.
• Lavage (introduction of heated solutions into the body cavity).
• Extracorporeal internal warming. Without extracorporeal warming methods in well-equipped clinics, the likelihood of a favorable outcome in severe stages of hypothermia is reduced to zero.

lavage

• Intestinal and stomach lavage . It is considered not very effective, since a very limited surface is heated with solutions. This technique is used in combination with others.
• Bladder lavage . Provides minimal and slow warming due to the small area of ​​influence.
• Closed thoracic lavage . Quite an effective procedure. In two places of the chest (front and back), thoracotomy tubes are placed through which a 40 ° C isotonic solution is supplied. This procedure can provoke fibrillation. It is used for cardiac arrest and the presence of a heart-lung machine.
• peritoneal lavage . Used in stable patients. Quickly warms the liver. Warming rate 1–3 °C per hour. After the temperature in the rectum rises to 33-34°C, the procedures are stopped so as not to create overheating against the background of unrecovered thermoregulation.

The choice of internal warming method is evaluated in terms of heat input and adverse effect on blood circulation. For example, pleural lavage reduces the quality of chest compressions, so other methods are chosen.

If ECMO is not used, the current view includes:

• conducting mechanical or manual resuscitation;
• warming until the restoration of independent blood circulation;
• sources of external heat only around the body (a heated blanket under the victim and one of the same blanket on him);
• bladder lavage or peritoneal lavage.

Extracorporeal methods of warming

Dextran refers to hemodynamic drugs. It slowly penetrates through the walls of blood vessels, therefore it remains in the blood for a long time, normalizing hemodynamics, increasing pressure, eliminating tissue swelling. After its application, the ability of the cellular elements of the blood to aggregate (glue) decreases and the fluidity of the blood improves. By creating a high oncotic pressure in the urine, it has a diuretic effect.

Ringer's solution refers to drugs that replenish not only the volume of blood, but also electrolytes (sodium, potassium, calcium).

Usually, after replenishment of the volume of fluid, blood pressure is restored. If hypotension still persists, use small doses , which also enhances the contractile function of the myocardium and increases heart rate when bradycardia . Has been successfully used to eliminate pulmonary edema and acute heart failure.

By the 3rd day of being on ECMO, the victim begins to release fluid from the tissues - this process is facilitated by the appointment of diuretics, for example,. Diuretics are prescribed for the prevention of acute renal failure, as well as pulmonary and cerebral edema.

Solutions glucose are also shown to the patient, because during warming, its level in the body decreases. Prolonged trembling also causes hypoglycemia , since this process consumed all the glycogen stores in the liver and muscles and the body has nowhere to draw glucose from.

Procedures and operations

The use of a heart-lung machine or extracorporeal membrane oxygenation (ECMO) is indicated for hypothermia III-IV with cardiac arrest or significant circulatory instability, if the use of peritoneal and pleural lavage was ineffective.

ECMO It is a safe method with high survival rates. It allows you to very quickly restore blood circulation, maintain tissue oxygen saturation, remove CO 2, conduct rapid warming, which can be controlled.

This is possible by actively (using a pump) forcing blood into the circuit, passing it through an oxygenator with a membrane and returning oxygenated blood to the bloodstream. Thus, it is an artificial replacement system for lung function (gas exchange) and blood circulation, which ensures the delivery of O 2 to tissues in severe life-threatening disorders of hemodynamics and pulmonary gas exchange.

During the procedure, the function of the heart and lungs is completely artificially replaced. A prerequisite is to maintain the heat balance of the victim at an optimal level, which is achieved by using heat exchange devices (heat exchangers). They provide active warming of the blood as it passes through the extracorporeal circuit. The heat exchange process in modern oxygenators takes place inside the oxygenator. Warm water enters the oxygenator and is distributed through polyurethane fibers, which have good thermal conductivity, are biologically inert (do not activate the cellular components of the blood) and durable (breakthrough of the fiber with the penetration of water into the blood is excluded). Apply a different rate of warming: from 10 0 for 5 minutes to 10 0 for 1 hour. It is selected according to the patient's standing, since there are no standards for this parameter.

The most commonly used femoral cannulation approach is less traumatic and associated with a lower risk of air embolism, blood loss, and infectious complications. ECMO continues until spontaneous heart rate and temperature increase to 32 0 C and above. The flow of blood through the extracorporeal circuit is accompanied by the risk of increased thrombosis. Therefore, immediately upon connecting the patient to the device, it is recommended to maintain the level of hypocoagulation with heparin.

Survival rates with this method are from 23 to 100%. This depends on many factors: the rate of cooling of the body, the cause of hypothermia, the presence of concomitant diseases, the type of cardiac arrest.

This condition is most typical for infants, since they do not have a trembling reflex, subcutaneous tissue is less pronounced, and thermoregulation processes are imperfect. Heat transfer in a child is more intense than in an adult, therefore, more energy is spent to maintain a constant body temperature. Newborns, for example, can maintain their body temperature at an external temperature of at least 23 0 C. This is ensured by an intensive metabolism. The normal temperature in a newborn varies between 36.5 0 -37.5 0 C.

In premature babies, thermoregulation processes are so imperfect that even minor factors, such as a cold changing table, can lead to hypothermia. If this condition is not corrected in time, the development of multiple organ pathology is possible. The lower the weight of the child and the gestational age, the greater the temperature of the external environment he needs. Children with a gestational age of 24-25 weeks should be kept at an external temperature higher than their body temperature. Therefore, incubators or systems with radiant heating are used to heat them.

Low temperature in newborns

The risk group includes:

• newborns weighing up to 2500 g;
• past long-term resuscitation;
• with congenital defects;
• with CNS damage.

There are three degrees of temperature decrease in newborns: mild, moderate and severe.

With a mild degree provide:

• environment with a temperature of 25-27 0 С;
• constant contact with the mother (“skin to skin”) is the best prevention and treatment of hypothermia;
• breastfeeding, which is organized on demand during the day.

With an average degree:

• warm room with a temperature of 25-28 0 C;
• placing the child in an incubator (35-36 0 C), under a heater lamp or warming with a water heating pad and an electric heating pad placed between two blankets;
• skin-to-skin contact, provided the child is stable and the room is warm;

The temperature in the water mattresses and the air in the incubator is monitored hourly.

In severe hypothermia, rapid rewarming is provided by:

• the child's stay on a heating pad, but the temperature rises to 38 0 С;
• placing a newborn in an incubator (35-36 0 С);
• contact "skin to skin" in a warm room (not lower than 26-28 0 C) using an electric heating pad.

Hypothermia of infants (children under one year old)

This state is evidenced by a decrease in temperature to 35 0 . The temperature is measured after sleep with electronic thermometers. The kid becomes drowsy, lethargic, plays poorly. The child's breathing slows down, the pulse slows down, the skin turns pale.

What should be done in such cases? Change into dry clothes, attach to the chest, since contact with the mother is important, warm well, wrapped in a blanket and overlaid with heating pads. It must be said that hypothermia at this age is very rare, since caring parents often play it safe and dress warmer than necessary. Such cases occur with poor care by negligent parents.

Low temperature in children older than 1 year

Hypothermia at 2–3 years of age occurs after past illnesses, with reduced nutrition and weakened immunity. With insufficient nutrition, the metabolic rate and heat production are reduced. The loss of fatty tissue leads to poor thermal insulation, and this increases heat loss. The temperature may decrease after prolonged swimming. It also occurs as an adverse reaction when taking .

Malnourished children are prone to hypoglycemia, so frequent meals prevent hypoglycemia, replenish energy for heat production, and thereby eliminate hypothermia. It is necessary to ensure that the child is always warmly dressed (including a hat), especially in winter. A varied and nutritious diet, appropriate for age, is the key to a healthy immune system.

Cooling of older children occurs when immersed in cold water. And I must say that hypothermia occurs faster than in adults.

Unlike adults, in children, signs of life are present at a temperature of 17 0 C, and the heart rate is maintained at temperatures up to 20 0 and below. A characteristic feature in children with hypothermia is changes in mental status. Warming is carried out according to the same principles, but in children it occurs faster than in adults.

Quite a common occurrence hypothermia of the breast of a nursing mother . This happens when you stay in a draft or insufficient warming of the chest. Hypothermia is accompanied lactostasis - stagnation of milk in the ducts. The milk ducts are narrowed, and this makes it difficult for the outflow of milk. The condition is aggravated if a woman uses the wrong feeding technique and wears underwear that squeezes her breasts. The problem of lactostasis is faced by primiparous women in the first month after childbirth, since their ducts are narrower. If the milk comes in excess, and the newborn sucks little, the breast is not completely emptied from feeding to feeding, and this causes milk stagnation.

Overflowing of the breast with milk is accompanied by a feeling of swelling. The chest becomes hot, hard and sore. Pain worsens during feeding.

More often, lactostasis is local, that is, local. In this case, a certain lobule of the mammary gland becomes rough, it is painful and the altered skin above it is determined. A woman's well-being usually does not suffer, if you do not take into account the discomfort and pain in the mammary gland. The temperature rises very rarely. However, feeding becomes painful and it is more difficult for the baby to suckle the swollen breast. He worries, refuses to feed, or sucks milk poorly from a stagnant breast, and this further increases lactostasis. Thus, there is a vicious circle.

Methods for the treatment and prevention of lactostasis are:

• Restriction of fluid intake. You need to consume no more than 1-1.5 liters, including the first liquid dishes.
• Frequent breastfeeding.
• Feeding primarily with "stagnant" breasts.
• Before feeding, expressing a small portion of milk, this softens the breast and it is easier for the baby to suck, taking the correct position at the nipple.
• Gently massaging the breast during feeding towards the nipple. You can not pinch the nipple with your fingers (like scissors) - this technique disrupts the outflow of milk.
• Breast emptying after feeding pumping . Pumping is a necessity that helps free the stagnant lobule from milk. For this purpose, it is better to use .
• Mastering several feeding techniques and constantly alternating them. In this case, all lobes of the gland are better released from milk.

When performing these activities, the effect occurs in 24-48 hours. If this does not happen, you need to see a doctor.

Diet for hypothermia

The nutrition of a person who has undergone mild hypothermia should be balanced, moderately sparing and fractional. The most suitable during this period is food within. It can be considered as a complete nutrition suitable for continuous use. The diet excludes fried and fatty foods, spicy spices and seasonings that irritate the mucous membrane of the gastrointestinal tract. Food is steamed, boiled in water, or baked (without a rough brown crust) and rubbed at first (but not necessarily). Prepared in this way, it does not irritate the gastrointestinal mucosa and contributes to its recovery.

The basis of the victim's nutrition is well-boiled various cereals, soups, boiled meat and fish, minced meat and fish products. At the end of cooking, a piece of butter or vegetable is added to cereals and soups. Meat and fish dishes can be seasoned with a sauce based on milk or sour cream.

Fruits and vegetables are also essential components of the diet. Only acidic fruits (lemon, grapefruit, tangerines) are excluded, which can unnecessarily irritate the mucous membrane and grapes, which have a rough skin and cause bloating. Other fruits can be consumed peeled. From vegetables it is better to refuse radishes, radishes, mushrooms, legumes containing coarse indigestible fiber. The rest of the vegetables the patient should first use stewed or boiled - they are easier to digest and do not cause discomfort in the stomach and intestines. With good tolerance, a transition to the use of raw vegetables is possible.

Plentiful warm drink (1.5-2 liters) will help eliminate the effects of hypothermia and restore the normal functioning of all organs. Acidic drinks should be abandoned (citrus juices, drinks with lemon juice, cranberry juice and juice). You can drink water, decoctions of herbs and dried fruits, green tea with honey. Of course, you need to completely eliminate unhealthy sweet drinks with gas (Cola, Pepsi, lemonade and others).

The victim, who is on ECMO, receives fluid and nutrient solutions through the ports of the system. He receives liquid in a volume of 120 ml per kg. Parenteral nutrition is organized adequately in the mode of hyperalimentation (at the rate of 50-60 kcal per kg). Subsequently, for some time, the patient can eat liquid food through a nasogastric tube, and when the condition improves, he can eat food on his own in the usual way.

However, the patient's gastrointestinal tract recovers gradually and cannot fully perform its function, therefore, during the recovery period, nutrition is organized very sparingly. At the discretion of the doctor and depending on the condition of the patient, you can start eating with or immediately from the diets of the main tables according to Pevzner:, with the transition to.

Surgical diets provide maximum unloading of the gastrointestinal tract and sparing. Meals begin with decoctions of rice, fruit and rosehip decoctions, broths, liquid jelly. Liquid mashed cereals, slimy soups, vegetable puree, steamed meat soufflé, protein omelets, crushed soft-boiled egg are gradually introduced. In the diet, the amount of protein, fat and portion size gradually increases.

Rhabdomyolysis - massive destruction of muscle tissue - is a dangerous complication. Rhabdomyolysis usually results in the development myoglobinuric nephrosis (at the same time, protein is found in the urine myoglobin ), which is complicated by acute renal failure. If frostbite of the limbs occurs in parallel, its typical complication is gangrene .

The cardiovascular system

The risk of ventricular fibrillation increases, which is facilitated by any changes: a sharp change in body position, fluctuations in myocardial temperature, a small temperature difference between endocardial and myocardial cells. At a temperature of 24 ° C, cardiac arrest is possible.

Blood system and hematological complications

Hypothermia causes an increase in blood viscosity, and this, in addition to the risk of thrombosis, disrupts the function of all organs. Part of the fluid from the vessels (since their permeability increases) passes into the interstitial spaces and the volume of intravascular fluid decreases significantly, which explains the increase in blood viscosity.

Severe hypothermia is accompanied coagulopathy - disseminated intravascular coagulation. Rapidly developing DIC (several hours-days) causes, slowly developing (weeks-months) - and, which is associated with excessive education thrombin and fibrin in blood.

Respiratory system

The initial response to hypothermia is to increase the respiratory rate, so it develops respiratory alkalosis . With aggravation of hypothermia, there are bronchospasm and increased secretion of mucus in the bronchi. Against the background of a decrease in immunity in the lungs, the flora is activated and conditions are created for the development pneumonia . It is detected on the second or third day, and over time, the prevalence of pneumonia increases. As breathing cools down and slows down, carbon dioxide is retained, so it develops respiratory acidosis which increases the risk of occurrence. Respiratory arrest occurs with deep hypothermia.

Often develops later respiratory distress syndrome , which is a consequence of damage to the membrane of the capillaries and alveoli of the lungs during hypoxia. With this syndrome, gas exchange in the lungs decreases, which leads to respiratory failure, which in turn increases hypoxia.

Nervous system

The consequence of hypoxia is the inhibition of the function of the central nervous system and development. There is a violation of consciousness of varying degrees: from stupor to coma of varying degrees. Consciousness is lost at 30°C, and the regulation of blood flow in the brain at 25°C. Progressive inhibition of the function of the nervous system leads to. In cases of exit of the victim from a critical condition, long-term consequences take place: swallowing disorders, neurological and mental disorders.

Kidney function

At the first stages of hypothermia, their function is enhanced and diuresis . This is due to an increase in renal blood flow with narrowing of peripheral vessels. As the condition worsens, cardiac output gradually decreases, and, accordingly, renal blood flow and glomerular filtration rate (may decrease by 50%). Severe hypothermia leads to acute tubular necrosis and kidney failure , which is observed in 40% of the victims.

Gastrointestinal tract

Gastrointestinal bleeding is associated with the formation of acute erosions and ulcers in the gastric mucosa as a result of spasm of the vessels that feed the stomach. In many victims, after warming on the second day, there is acute pancreatitis . The prevalence of the inflammatory process is progressing. Its development is associated with the activation of enzymatic processes in the gland and an increase in the number of enzymes. This occurs compensatory in order to increase the amount of energy.

Against the background of cooling, spasm and swelling of the ducts of the gland and Vater's nipple , and this leads to the accumulation of enzymes in the gland. With increasing hypoxia, the parenchyma of the organ is damaged. During warming activities, enzymes are activated and tissue digestion itself occurs (foci of inflammation and necrosis appear). If the patient had chronic pancreatitis , its exacerbation is noted.

compartment syndrome extremities (myofascial form) can be considered as atypical consequences of hypothermia. The syndrome is associated with a prolonged decrease in blood circulation in the muscles of the fascial canal. Subsequently, it develops, necrosis of nerves and muscles and contracture are possible. If blood circulation is not restored and the ischemic syndrome progresses, gangrene may develop. Irreversible damage occurs after 12 hours from the onset of symptoms: severe pain, blanching of the limb, impossibility of movement and numbness of the fingers.

Forecast

Modern approaches to the treatment of this condition guarantee a favorable outcome with the restoration of all neurological functions. This is possible even after asystole which lasted several hours. If using traditional methods of warming (lavage, dialysis) many did not survive, then with the use of ECMO the prognosis is more favorable. The best prognosis is noted when continuous cardiopulmonary resuscitation was performed from the moment of cardiac arrest until ECMO rewarming.

The best chances are for patients in whom hypothermic cardiac arrest is registered against the background of health, is immediately recognized, resuscitation is immediately started, and the ECMO system is connected in a timely manner. You can focus on the maximum time to start resuscitation from the time of cardiac arrest with deep hypothermia: 25 minutes for adults over 60 years of age and 40 minutes for newborns.

Cardiac arrest is preceded by hypoxia, which causes irreversible brain damage within minutes. In this regard, victims with unstable hemodynamics should be urgently transported to ECMO centers.

Summing up, there are many factors that can affect the prognosis:

• Availability hypoxia (the most important factor) and asphyxia . The survival rate is 64% if there was no asphyxia before hypothermia. With asphyxia and subsequent hypothermia (being under an avalanche of snow or drowning), the prognosis is unfavorable.
• Individual characteristics (age, injury, other diseases).
• cooling rate.
• Features of cardiac arrest (at what temperature, was there hypoxia before circulatory arrest, the beginning of resuscitation).
• Environment (water, snow or air).
• The quality of rescue operations (training of personnel, speed of transportation to specialized centers).
• Proximity of relevant institutions.

List of sources

• Kulenkova E.G., Likhodets V.I. The use of profezim in the treatment of frostbite // Disaster Medicine. – 2005; 1:38–40.
• Rybdylov D.D. Diagnosis and treatment of local cold injury. Abstract dis. ...cand. honey. Sciences. - Irkutsk, 2004. - 25 p.
• Mishchuk N.E. Cold sickness (Hypothermia) // Journal of Emergency Medicine - 2006, 4(5)
• Tsarev A.V. A method of intensive therapy for general hypothermia // Journal of Emergency Medicine - 2017 No. 2 (81).
• Litvitsky P. F. Clinical pathophysiology. Textbook: Textbook. - 2015, p.185-198

An increase in body temperature is a classic symptom of the development of various diseases and pathological conditions. This phenomenon occurs quite often and can hardly be surprising. But sometimes the thermometer readings fall below the norm, which also requires close attention. After all, an abnormal decrease in temperature may indicate the occurrence of various health problems, including quite serious ones.

When is the temperature considered low?

It is believed that a normal temperature for a healthy person is from 35.8 to 37.0 ° C. An indicator of 36.6 ° C is an average, the given deviations in both directions are considered acceptable by doctors.

If the temperature drops below the mark of 35.8 ° C, they speak of pathology. If such a phenomenon is constantly observed in a person, it may well indicate the development of quite serious diseases that require immediate correction under the supervision of a qualified specialist. These symptoms cannot be ignored.

In the event that the temperature drops to 29.5 ° C and below, loss of consciousness occurs. And its further decrease is fraught with the onset of coma, which, in turn, can cause death.

There are a number of factors that can cause a decrease in temperature in humans. Among them, the most common are:

• physical hypothermia;
• overwork;
• recent infectious or viral illnesses;
• significant weight loss below normal;
• hypotension and neurocirculatory dystonia;
• anemia
• hypovitaminosis of vitamin C;
• pregnancy.

There are also other, more rare and serious pathologies that can cause such a violation. They are presented:

• exacerbations of chronic ailments;
• diseases of the endocrine system;
• acquired immunodeficiency syndrome (AIDS);
• brain ailments;
• severe intoxication;
• significant blood loss;
• shock
• radiation sickness.

It is worth noting that in some situations, a decrease in temperature can be explained by self-medication attempts and the consumption of certain medications.

Physical hypothermia

A natural decrease in body temperature occurs if a person is very cold. This state is called physical hypothermia. If the body temperature continues to fall, and the person fails to warm up, the metabolic processes in the body gradually stop, which is fraught with the development of a fatal outcome.

Overwork

Doctors are sure that one of the possible reasons for the decrease in temperature is chronic fatigue syndrome, which has developed against the background of a constant lack of sleep or due to exposure to frequent stressful situations. Overfatigue negatively affects the activity of all organs and systems, causes an overload of the body and a state of exhaustion.

Recent illnesses

If a person has recently had an acute respiratory disease, acute respiratory viral infection or influenza, he may have a low body temperature for some time. Such a phenomenon is considered a variant of the norm. Past infections deplete the body, after which the immune and nervous systems need time to restore their functionality. As you know, the center of thermoregulation is part of the nervous system.

Weight loss

The temperature can drop below normal if a person develops cachexia - exhaustion of the body, which is accompanied by a sharp drop in body weight, decreased performance and significant general weakness. Even long-term adherence to strict diets and fasting can cause a decrease in body temperature below normal levels. But cachexia poses a serious threat to health and requires treatment in an inpatient department.

Hypotension

Hypotension refers to low blood pressure. And one of the possible reasons for its decline is neurocirculatory dystonia. This condition is a whole complex of disorders in the functioning of the cardiovascular system, it develops due to impaired neuroendocrine regulation. Patients with neurocirculatory dystonia are usually worried not only about hypotension and low temperature. They may also complain about:

• increased fatigue and muscle weakness;
• headache ;
• feeling of interruptions in the work of the heart;
• shortness of breath
• sweating.

Anemia

Low body temperature can be fixed with different types of anemia. With such ailments, the level of hemoglobin in the body decreases, due to which tissues and cells experience oxygen starvation. Iron deficiency anemia is considered the most common, in which a decrease in hemoglobin is due to iron deficiency. The classic manifestations of such an ailment:

• severe weakness, malaise, deterioration in performance;
• dry skin, dry hair, brittle nails;
• drowsiness, headaches, dizziness, etc.

Anemia can develop for various reasons, only a doctor can identify them during a comprehensive examination.

Even a slight lack of vitamin C can adversely affect the general condition of the body and the activity of all organs and systems. Deficiency of this substance causes a decrease in general immunity and contributes to the occurrence of anemia. And with the progression of such hypovitaminosis, a person develops manifestations of scurvy: fragility of blood vessels, the appearance of hemorrhagic rashes, increased bleeding of the gums, etc.

Pregnancy

In some situations, temperature indicators decrease below normal in women awaiting the birth of a baby. Moreover, such symptoms are sometimes observed even before the expectant mother finds out about her interesting situation. Most likely, its occurrence is associated with hormonal changes. A decrease in temperature during pregnancy can be supplemented by manifestations of hypotension and early toxicosis.

Low temperature: norm or pathology?

Even with full health, people may periodically experience a slight decrease in body temperature. Most often, such symptoms are fixed in the morning. But at the same time, the thermometer should not fall below 35.8 ° C.

• the absence of any unpleasant symptoms;
• full preservation of vivacity and efficiency;
• confirmation of the absence of any pathologies after the examination.

A persistent decrease in temperature is an occasion for a visit to the doctor, a full examination and selection of adequate therapy. Most often, a patient with such a violation is shown to conduct a general and biochemical blood test, ECG (electrocardiogram), ultrasound (ultrasound) of internal organs. An examination of the endocrine organs (in particular, the thyroid gland), an x-ray of the chest area and other additional diagnostic manipulations may also be needed.

Hypothermia is a drop in core body temperature below normal levels. When the body temperature is greatly reduced, the heart rate and metabolism slow down, leading to a decrease in oxygen consumption, loss of consciousness and even cardiac arrest. Body temperature between 32°C and 36°C is an indication of mild hypothermia. ,

Temperatures below 32°C are observed during the transition from moderate to severe hypothermia. The lower the temperature, the stronger. It should be noted that most home thermometers do not register temperatures below 35°C and thus are not reliable indicators of profound hypothermia.

Hypothermia can occur even at moderate outside temperatures (from -1°C to +10°C), especially in windy or humid weather (water takes heat from the body approximately 25 times faster than air). The elderly are especially vulnerable to hypothermia because the ability to regulate body temperature decreases with age. Hypothermia is a common cause of death among outdoor enthusiasts and requires immediate medical attention.

WHAT CAUSES HYPOTHERMIA

Being outside in cold weather, especially in windy and rainy weather. Hypothermia can also appear in moderate cold or even indoors, especially in infants or the elderly.

Immersion in cold water quickly causes hypothermia, but even warm water (20°C) can cause hypothermia if left in it for a long time.

Risk factors include alcohol use; diabetes; diseases of the pituitary gland, thyroid noah gland or adrenal glands; overwork; use of beta-blockers (often prescribed to treat high blood pressure).

SYMPTOMS OF HYPOTHERMIA

Numbness beginning in extremities.

Pale, bluish or grayish skin tone (cyanosis).

Slurred speech or stuttering.

Confusion of consciousness.

Unsteady gait.

Signs of an emergency: drowsiness, very slow pulse and breathing, dilated pupils, loss of consciousness.

DISEASE PREVENTION

Wear several layers of warm, waterproof clothing in cold or wet weather. Keep your head warm (since heat quickly evaporates through the skull). Don't stay too long in the cold. Remember that fatigue, poor nutrition and can increase the risk of hypothermia.

Alcohol, drug use and lack of oxygen at altitude can lead to impaired self-control and prolonged exposure to cold. Alcohol also increases heat loss.

Keep an eye on elderly relatives or friends during cold weather.

DIAGNOSIS OF HYPOTHERMIA

Hypothermia is suspected when severe, uncontrollable shivering occurs, or when exposure to cold causes confusion, stuttering, or drowsiness.

The doctor may use a special low-temperature thermometer to measure body temperature.

TREATMENT OF HYPOTHERMIA

Call for medical help or go to the nearest emergency room immediately.

Anyone experiencing hypothermia outdoors should enter (or be brought in) indoors as soon as possible. Wet clothes should be removed and replaced with dry clothes, blankets or a warm sleeping bag. Make sure your head is also covered.

Skin-to-skin contact or careful use of an electric blanket is effective for warming. Start by warming up the torso, as warming up the extremities can cause blood to drain from vital organs.

Warm, non-alcoholic drinks can be given to a person if he is conscious.

In the medical office, the patient may be given warm fluids intravenously and warm oxygen. In severe cases, direct heating of the patient's blood may be used.

WHEN TO SEE A DOCTOR

Attention! Call an ambulance if the person is hypothermic. Prior to the arrival of doctors, the actions described above must be taken.

Signs of hypothermia should be known to every person who, due to their lifestyle or work, is forced to spend quite a long time in cold conditions, including in water. Parents must also have such information in order to understand that their child is in danger. Prevention of hypothermia is a simple task if the problem is not caused by pathological processes in the body. It is necessary to carefully monitor the condition of the body and understand that lowering the temperature can be a serious problem.

What is this about?

Symptoms of hypothermia are best shown by the most common thermometer - it is necessary to measure body temperature. Control rules assume that the axilla is dry. If moisture accumulates here, it takes away body heat, which leads to incorrect thermometer readings. The duration of the data check is three minutes. Hypothermia of the body is a state when the temperature is less than 35.5 degrees.

Where did the trouble come from?

Most often, the problem is provoked by a long stay at a low temperature. It is quite simple to eliminate such causes of hypothermia, if irreversible processes have not occurred. You just need to deliver a person to a warm room, where the indicators return to normal. True, you need to understand that even short-term hypothermia greatly affects the immune system, conditions are created in which bacteria and infections easily multiply. If this still happened, you should immediately take medications that prevent the development of the disease. However, the best option is to prevent the development of hypothermia, especially in immunocompromised patients.

temperature and diet

The human body is a complex system where numerous reactions take place, in which heat is produced. It is it that allows you to maintain body temperature in a normal state. When doctors explain that this is hypothermia, they often point out that this condition is typical for people with a slow metabolism.

With problems with metabolism, too little energy is produced, the body temperature drops. Malnutrition is the most common cause of metabolic disorders. The body does not have access to those components, trace elements that are needed for heat release reactions. What is hypothermia? A pathological condition in which (if provoked by diet) the subcutaneous supply of fat cells responsible for heating is reduced. To cope with the problem, it is necessary to normalize the diet. Chilliness will not go away immediately, but over time it will gradually disappear.

Pathology and hypothermia

What is this reason? Often, low temperature is provoked by endocrine diseases. Most often, the symptom signals hypothyroidism, in which the functionality of the organs is noticeably weaker than normal. The hormones that the thyroid gland should produce control the metabolic processes in the body, and with a shortage, biochemistry slows down greatly. The lack of energy flow causes the temperature to drop. Treatment of hypothermia for this reason must be carried out under the supervision of a doctor - the patient is recorded for examination by an endocrinologist, who conducts a complete study of the body, takes tests.

Hypothyroidism is additionally indicated by weight gain for no apparent reason, drowsiness, lethargy, and bowel problems (constipation). Many patients complain of chilliness, general weakness, weakening of memory. Hair becomes dull, skin becomes dry.

Diabetes and hypothermia

What is this reason? Diabetes mellitus is a common and very dangerous endocrine disease, which is characterized by a decrease in body temperature. The decrease is often provoked by the absence of oxidative processes involving glucose, which does not allow the body to produce the energy volumes necessary for functioning. Patients note chilliness, suffer from thirst, which cannot be quenched even by drinking plenty of water. At the same time, the urge to urinate is constantly felt, and the limbs become less sensitive.

Liver and hypothermia

One of the fairly common serious diseases is liver failure. With this pathology, the body, which normally forms a store of glycogen, actively consumes it without accumulating again. With the correct functioning of the body, energy is obtained from incoming food, and the accumulated is resorted to only when there is a shortage of components in external sources, but the insufficiency of the functioning of the liver leads to the fact that there are no reserves at all, and incoming products cannot be processed really effectively. Lack of energy provokes the establishment of a lower temperature.

Anemia and hypothermia

This pathology negatively affects the metabolism and provokes a decrease in temperature. The condition is characterized by depletion of the blood with oxygen, due to which the tissues do not receive the nutrition necessary for normal functioning. This blocks oxidative processes, which means that energy production is simply impossible.

Anemia is manifested not only by persistently low body temperature, but also by an increased heart rate, shortness of breath. The head may hurt and spin, “flies” appear before the eyes, the limbs go numb, the skin turns pale, and the fingertips may even acquire a bluish tint. With anemia, people quickly get tired, feel indifferent and apathetic, weak.

Neurology and hypothermia

If the nervous system cannot function normally, this manifests itself in a number of characteristic symptoms, which are often accompanied by a persistent decrease in body temperature. This is most typical for injuries from which the spinal cord has suffered, but can also be observed in other pathologies associated with paralysis of large muscle tissues. This condition eventually leads to atrophy of the affected area, but it is the fibers of such organs that are the place where the breakdown of nutrients occurs, during which energy, which is so important for the functioning of the body, is released in the form of heat. As soon as the elements of the body, where the reaction can occur, lose their efficiency, the body temperature drops. This condition is characteristic of a person all the time, improvements are not observed for a very long time, maintenance therapy is necessary.

Malignant neoplasms

It is known that oncological diseases greatly affect the body as a whole. The presence of such a pathology can also affect the level of temperature. Some patients experience hypothermia, while others suffer from hyperthermia. Much depends on the specifics of a particular case, the site of the body affected by the tumor, as well as the general condition of the patient.

Hypothermia is more often detected if the hypothalamus is affected, since this element of the brain is responsible for controlling the temperature level. With the growth of the tumor, its functionality is gradually lost, the regulation of body heating is disturbed. At first, a person does not even feel a headache, but at a later stage, “nausea” is observed along with it, and the head is often dizzy. It is possible to assume the presence of a malignant neoplasm by a persistent decrease in body temperature, therefore, it is impossible to ignore such a factor in the absence of more obvious explanations for the reasons for its appearance. It is necessary to visit a doctor and undergo a complete examination of the body.

What else influences?

With a number of pathologies, the blood vessels dilate, which leads to a rush of blood to the integument. Accordingly, the heat transfer increases, the body temperature as a whole decreases. This can be observed with a number of skin diseases, including psoriasis, as well as with sufficiently large inflammations, burns. When the underlying cause is eliminated, the temperature returns to normal.

In some people, the medications taken greatly affect the heating of the body. So, if you drink too many antipyretics, the likelihood of hypothermia is high. Sedatives, anesthetics on a narcotic basis can lead to the same effect.

For help!

The first thing a person should do, having fixed a persistent decrease in body temperature, is to consult a doctor. First, they are recorded with a therapist, since hypothermia is not an independent disease, but only a symptom that indicates a number of disorders. When examining the body, the doctor will suggest what causes could cause it, and refer the patient for further examinations to clarify the situation. Once the root cause is found, therapy can begin. First, a urine and blood test is performed, then, if necessary, special studies are done, including tomography, ultrasound. Most often, the patient is offered to consult with a neurologist, oncologist, endocrinologist. At the same time, you should not panic - hypothermia can be caused by completely harmless problems, which can be eliminated quite easily.

Risk group

Quite often, a decrease in temperature is provoked by alcohol intoxication. People who abuse alcohol are the most extensive risk group for a pathological condition. If a person stays in the cold for a long time, there is a possibility of such a strong decrease in body temperature that the consequences will be irreversible. To prevent such a situation, it is necessary to control the volume of consumption of "strong" drinks and not be in the cold in a state of intoxication. If friends, relatives, close people find themselves in such a situation, it is necessary to assist them - take them to a warm place, and provide first aid with a persistent decrease in body temperature.

Having met the term "hypothermia", not everyone will guess what it is. In fact, hypothermia simply means hypothermia. But in our body, which is a complex system, not everything is so simple. Let's figure it out, hypothermia - what is it, how to reveal the reality of the risk of freezing, what threatens a person with such a condition and how to competently warm the victim without harming him.

The state of hypothermia is a serious threatening factor for internal life processes, therefore, a supercooled person immediately needs to be warmed up, but according to the correct algorithm, in order to avoid mistakes and complications.

In medical practice, a person may be subjected to cooling specifically, for example, for anesthesia. In this case, hypothermia is considered artificial and controlled, and the patient is not at risk to life, since all indicators are regulated, and the cooling itself is kept at a safe level.

Causes of Hypothermia

In the human body, temperature indicators are not the same - those that we see on a conventional thermometer in the armpit reflect only degrees of the peripheral temperature of the shell. The central one, inherent in the so-called core - the brain, internal organs, central large veins and arteries, is always higher - up to 38ºС.

The hypothalamus, the main regulator of homeostasis, is responsible for the warmth of the human body and its stability. It is he who keeps the temperature indicators in the same state in order to provide optimal conditions for a healthy life.

• When external heating is observed, that is, hyperthermia, a person begins to sweat intensely, blood vessels and pores expand, thirst appears, and the body cools itself through the excreted liquid.
• When a person is exposed to an external cold environment, and hypothermia is observed, then the vessels narrow, heat loss is minimized, the overall metabolism drops - the body accumulates precious heat.

Natural hypothermia, as a rule, overtakes a person who finds himself in a certain cold environment for a period sufficient for the onset of cooling to 35 ° C and below, when the body ceases to make up for large losses of internal heat.

• For a long time, a person stays in severe frost.
• A person finds himself in a reservoir of cold water and there is no way to immediately get out.
• A person is immobilized due to injury, accident, injury, fainting, shock, seizure, coma, and it is cold outside.
• Alcohol intoxication in a cold season outside a heated room.

Remember! Any person sitting or lying still on the street, when the atmosphere is cold enough, should cause alarm in others - he needs urgent heating, because he has hypothermia!

Science not so long ago understood what the advantages of specially induced hypothermia are, and began to successfully introduce it into medical practice. Artificial local cooling is widely used to stop bleeding, in the treatment of inflammation, and for anesthesia in injuries. General cooling is practiced during surgical interventions on the brain and heart, as well as in strokes with hemorrhage or injuries to the skull.

How to recognize hypothermia

We mentioned above the temperature difference in our body, reaching up to 1.5ºС, but these are normal indicators under normal conditions. And with supercooling, the degrees of the core and shell change in different ways. Hypothermia is fraught with the fact that the internal organs can be equally cooled, like the skin. For example, this happens when a person flounders in ice water for a long time - the muscles under the skin heat up, the organs cool down.

Therefore, to obtain a real picture of hypothermia, it will be incorrect to measure the temperature in the usual way - in the armpit, that is, the axillary temperature. It will show the value of the peripheral degrees, while the degrees of the central indicators are considered vital.

To have an idea of ​​the degree of heat in the core of the body, the temperature should be measured through the following zones:

• through the nasopharynx;
• through the rectum;
• through the external auditory canal;
• through the bladder.

The usual thermometer on mercury is not very suitable for such manipulations, besides, it has a minimum value on the scale - only 34ºС, and hypothermia often needs lower values.

Therefore, to obtain a more accurate picture of hypothermia, what kind of cooling stage it is, an electronic thermometer is needed, and in addition - sensors and probes for insertion into the cavities.

Remember! Even if an ordinary mercury device shows a minimum, for those around it is a signal to urgently call an ambulance and begin immediate independent steps to warm the victim.

Varieties of hypothermia according to the degree of cooling

In order to adequately provide assistance with hypothermia, you need to find out its degree - how badly a person is frozen. It is customary to divide the concept of "hypothermia" into 3 stages - into mild, moderate and severe.

• The light stage involves cooling from 35°C to 32.2°C.
• Medium - from 32.2ºС to 27ºС.
• Heavy - lower than 27ºС.

At each stage, various external manifestations of hypothermia can be observed, as well as internal changes from exposure to cold.

• With a mild degree, a person cannot stop trembling, cold is felt to the point of pain, the body is constrained by vasospasm, convulsions are possible, apathy quickly sets in, and a state of falling asleep comes.
• With an average degree, when the body has not cooled down so critically, such external signs can be observed: loss of orientation, apathy, unwillingness to move, drowsiness, confusion, trembling in the body, respiratory and heart rhythm disturbances.
• In a severe stage, all systems fail - cardiac, respiratory, circulatory, nervous, while consciousness is confused to a delusional state, a person loses the ability to move, falls into oblivion. Then a coma sets in, and the pupils stop responding to directional light.

Remember! With mild to moderate hypothermia, the victim can still warm up on their own, thanks to outside help. At a severe stage, the biological mechanism of self-regulation is turned off, and without warming, a person dies.

How to properly warm a victim with hypothermia

If the victim of the cold can move independently or with someone's help, then this indicates a moderate - either mild or moderate - degree of hypothermia. When a person is not even able to move, then doctors in a hospital should take care of his further professional warming, however, until they arrive, a person cannot be left in an icy environment.

• The first task when detecting a freezing person is to remove his further cooling.
• If possible, the victim is transferred to a warm room, heated transport cabin, salon, change house and other warm object.
• The body and head are covered with warming things - a blanket, a blanket, a coat, a fur coat, woolen clothes.
• You can use warming with heating pads, or their substitutes - plastic bottles with hot water, but you need to warm the chest and head, not the limbs.
• They give a warm drink without alcohol - water, tea, milk, any other drink.
• You can give a frozen person a bath with water at about 38ºС - 40ºС.

An excessively cooled body will need resuscitation measures that will be performed by an ambulance or rescue team. While they are gone, a person is wrapped in warm clothes and given a hot drink if he is not in a coma. The slightest opportunity to transport a freezing person to a heated room must be used by constructing any semblance of a stretcher.

Common heating mistakes

Often mistakes caused by illiteracy can turn warming into an additional risk factor.

We will describe what cannot be done to warm up the body of a frozen person, and why.

• Alcohol should not be allowed to drink - it dramatically expands the blood vessels, which leads to an even greater loss of internal scarce heat.
• It is impossible to rub the limbs with alcohol - cold blood from the more chilled limbs will rush into the general bloodstream and quickly reach the internal organs, cooling them even more.
• You can not rub the body of the victim with snow or ice - this will provoke a rush of warmer blood to the periphery and its outflow from vital organs and the brain.
• Such rubbing is especially unacceptable when there is a risk of frostbite.

Remember! Only heating with warm air, drinking, things or in the bath will be right!

Consequences of hypothermia

The stronger the degree of freezing, the more severe the consequences for the body. Hypothermia provokes pneumonia, frostbite of open areas of the body and limbs, failures on the part of all those involved in vital functions, systems and organs. A strong drop in core temperature often ends in death and requires resuscitation to bring a person who has undergone severe hypothermia out of a coma.