Each of us knows about the existence of such a thing as body temperature. In a he althy adult, its indicators should be in the range of 36-37 ° C. Deviations in one direction or another indicate the occurrence of a disease of any etiology or a violation of the thermoregulation of the body. This condition is not a disease as such, but it can cause destabilization of organs and systems, even lead to death. All warm-blooded mammals, including humans, have the ability to thermoregulate. This function has been developed and fixed in the course of evolution. It coordinates metabolic processes, makes it possible to adapt to the conditions of the outside world, thereby helping living organisms to fight for their existence. Each individual, regardless of species, status or age, is exposed to the environment every second, and dozens of different reactions continuously occur in his body. All these processes provoke fluctuations in body temperature, which, if notthermoregulation, which controls them, would lead to the destruction of individual organs and the whole organism. In principle, this is what happens when there is a violation of thermoregulation. The causes of this pathology can be quite diverse, from trivial hypothermia to serious diseases of the central nervous system, thyroid gland or hypothalamus. If a person suffering from such ailments has a thermoregulation system that does not cope well with its functions, in order to correct the situation, it is necessary to treat the underlying disease. If thermoregulation is impaired in a he althy person, and the reason for this is external conditions, such as the weather, you need to be able to provide first aid to such an injured person. Often his future he alth and life depend on it. This article provides information on how body temperature is regulated, what symptoms indicate failures in thermoregulation, and what actions should be taken in this case.
Features of body temperature
Impaired thermoregulation is inextricably linked with body temperature. Most often, it is measured in the armpit, where normally it is taken equal to 36.6 ° C. This value is an indicator of heat transfer in the body and should be a biological constant.
Nevertheless, body temperature in small ranges can vary, for example, depending on the time of day, which is also the norm. Its lowest values are recorded between 2 and 4 am, and the highest between 4 and 7 pm. In different parts of the body, temperature indicators also change, and this does not depend on the time of day.depends. So, in the rectum, values from 37.2 ° C to 37.5 ° C are considered normal, and in the mouth from 36.5 ° C to 37.5 ° C. In addition, each organ has its own temperature norm. It is highest in the liver, where it reaches 38°C to 40°C. But from climatic conditions, the body temperature of warm-blooded animals should not change. The role of thermoregulation is precisely to maintain it constant under any environmental conditions. In medicine, this phenomenon is called homoiothermia, and a constant temperature is called isothermia.
Violation of the body's thermoregulation is characterized by an increase or decrease in body temperature. There is a clear range of its upper and lower values, beyond which it is impossible to go, because this leads to death. With certain resuscitation measures, a person can survive if their body temperature drops to 25°C or rises to 42°C, although cases of survival at more extreme values \u200b\u200bare known.
The concept of thermoregulation
Conventionally, the human body can be represented as a kind of core with a constant temperature, and a shell where it changes. Processes take place in the core, as a result of which heat is released. Heat exchange occurs through the shell between the external environment and the core. The source of heat is the food that we consume daily. During the processing of food, the oxidation of fats, proteins, carbons occurs, that is, metabolic reactions. During their flow, heat production is formed. The essence of thermoregulation is to maintain a balance between heat transfer and the formation of heat production. In other words, in order for the body temperature to be kept within the normal range, the shell must give off as much heat to the environment as it is formed in the core. Violation of the thermoregulation of the body is observed when there is an excess of heat production, or, conversely, it is formed much more than the shell is able to bring into the environment.
This could be due to:
- environmental conditions (too hot or too cold);
- increased physical activity;
- inappropriate clothing for the weather;
- Taking certain medications;
- drinking alcohol;
- the presence of diseases (vegetovascular dystonia, brain tumor, diabetes insipidus, various syndromes of hypothalamic dysfunction, thyrotoxic crisis, and others).
Thermoregulation is carried out in two ways:
1. Chemical.
2. Physical.
Let's take a closer look at them.
Chemical method
It is based on the relationship between the amount of heat generated in the body and the rate of exothermic reactions. The chemical type includes two ways to maintain the desired temperature - contractile and non-contractile thermogenesis.
Contractile starts to act when you need to increase body temperature, for example, when you stay in the cold. We notice this by the rising of body hairs or by the running “goosebumps” which are micro-vibrations. They allow you to increase heat production up to 40%. With more severe freezing, we begin to shiver. It is also nothing but a methodthermoregulation, in which the production of heat production increases by about 2.5 times. In addition to involuntary reflex reactions to cold, a person, moving, himself can raise the temperature in his body. Violation of thermoregulation in this case occurs when the exposure to cold is too long, or the temperature of the environment is too low, as a result of which the activation of metabolic reactions does not help produce the required amount of heat. In medicine, this condition is called hypothermia.
Thermogenesis can be non-contractile, that is, take place without the participation of muscles. Metabolism slows down or accelerates under the influence of certain medications, with increased production of hormones in the thyroid gland and in the adrenal medulla, with a more active sympathetic nervous system. The reasons for the violation of human thermoregulation in this case lie in the diseases of the above organs of the thyroid gland, the central nervous system, and the dysfunction of the adrenal glands. Information about temperature changes always enters the central nervous system. The heat center is located in a tiny part of the diencephalon, the hypothalamus. It has an anterior region responsible for heat transfer and a posterior region responsible for generating heat production. Pathologies of the central nervous system or dysfunction of the hypothalamus disrupt the coordinated work of these parts, which negatively affects thermoregulation.
The intensity of heat transfer, and in addition, some vascular functions are also influenced by thyroid hormones T3 and T4. In a normal state, in order to save heat, the vessels narrow, and in order to reduce it, they expand. Californianscientists have proven that hormones are able to “interfere” with blood vessels, as a result of which they stop responding to the amount of heat produced and to the body’s need for it. In medical practice, there is often a violation of thermoregulation in patients diagnosed with a brain tumor or thyrotoxic crisis.
Physical method
He does the work of transferring heat to the environment, which is carried out in several ways:
1. Radiation. It is characteristic of all bodies and objects whose temperature is above zero. Radiation occurs by electromagnetic waves in the infrared range. At an ambient temperature of 20°C and a humidity of about 60%, an adult loses up to 50% of his heat.
2. Conduction, which means the loss of heat when touching colder objects. It depends on the area of contact surfaces and the duration of contact.
3. Convection, which means the cooling of the body by particles of the medium (air, water). Such particles touch the body, take heat, heat up and rise up, giving way to new, colder particles.
4. Evaporation. This is a familiar perspiration, as well as the evaporation of moisture from the mucous membranes during breathing.
In conditions of inability to use these methods, there is a violation of the body's thermoregulation. The reasons for this may be different. So, convection and conduction are hindered or reduced to zero if a person is wrapped in clothes that exclude contact with air or any objects, and evaporation is impossible at 100% humidity. With anotherOn the other hand, a significant activation of heat transfer also leads to a violation of thermoregulation. For example, convection increases in the wind and increases many times in cold water. This is one of the reasons why people, even those who can swim well, die in shipwrecks.
Temperature regulation in old people
Above we examined what the thermoregulation of the human body is and the reasons for its violation, but without taking into account age-related features. However, in humans, the ability to control body temperature throughout life undergoes changes.
In old people, the mechanisms of the hypothalamus, which evaluate the temperature of the external environment, are disrupted. They do not immediately feel cold when standing on an icy floor, nor do they immediately react to hot water, for example, in the shower. Therefore, they can easily harm themselves (overcool, burn themselves). It has been observed that older people who do not even complain about the cold deteriorate their mood, unreasonable discontent appears, and when they create a comfortable climate, all these harmful “symptoms” of an senile nature decrease or disappear.
At the same time, many old people feel cold even at fairly comfortable air temperatures. They can often be seen on a warm summer day dressed in winter. Such changes in thermoregulation occur due to circulatory disorders and a decrease in hemoglobin levels.
Old people not only react to cold but also to heat in a slightly different way. At high ambient temperatures, their sweating begins later, and the restoration of the norm of body temperature indicators is slower. OthersIn other words, the symptoms of hypothermia or overheating in them begin to appear later than in young people, and the recovery of the body is more difficult.
Impaired thermoregulation in a child
Children's body is characterized by other features of the thermoregulation system. In newborns, it is very imperfect. Babies are born with a body temperature in the range of 37.7°C - 38.2°C. After a few hours, it drops by about 2°C, and then again reaches 37°C, which should not be a cause for concern. Higher rates may be a signal of the onset of a disease. The imperfection of the functioning of the thermoregulation system in infants should be compensated by the creation of suitable climatic conditions for it. So, up to 1 month in the nursery, the air temperature should be maintained at 32 ° C - 35 ° C if the baby is undressed, and 23 ° C - 26 ° C if he is swaddled. To stimulate thermoregulation, you need to start with the simplest thing - do not put a cap on your head. In babies older than 1 month, these temperature norms are reduced by about 2 ° C.
Children born prematurely have more serious problems with thermoregulation, therefore, in the first days, and sometimes even weeks, they are kept in special cuvettes. All manipulations with them, including the processing of the umbilical cord, washing and feeding, are also carried out in cuvettes.
The body's control over temperature stabilizes only by the age of 8.
Impaired thermoregulation in an infant can occur for the following reasons:
- inhibitory effects on the hypothalamus(fetal hypoxia, birth hypoxia, intracranial trauma during childbirth);
- congenital pathologies of the central nervous system;
- hypothermia;
- overheating (excessive wrapping);
- Medications (beta-blockers);
- change of climatic conditions (it happens when parents travel together with babies).
In infants, axillary temperature is considered normal between 36.4°C and 37.5°C. Lower values may indicate dystrophy, vascular insufficiency. Higher values indicate inflammatory processes occurring in the body.
Symptoms of impaired thermoregulation in hypothermia
Depending on the cause that caused failures in the control of body temperature, there are different signs that indicate a violation of the body's thermoregulation. Symptoms of hypothermia or hypothermia begin to appear when the body temperature drops below 35°C. This condition can occur with prolonged exposure to frost or in water. For the average person, the water temperature in the range of 26-28°C is considered acceptable, that is, you can stay in it for a long time. With a decrease in these indicators, the time that can be in the aquatic environment without harm to he alth decreases sharply. For example, at t=18°C, it does not exceed 30 minutes.
Hypothermia, depending on the complexity of the course, includes three stages:
- light (body temperature from 35°C to 34°C);
-medium (t=34°C to 30°C);
- heavy (t=30°C to 25°C).
Mild symptoms:
- goose bumps;
- cyanosis;
- body trembling;
- fast breathing;
- sometimes there is an increase in blood pressure values.
In the future, the violation of the processes of thermoregulation progresses.
The victim develops the following symptoms:
- low blood pressure;
- bradycardia;
- fast breathing;
- constriction of pupils;
- stop trembling in the body;
- disappearance of pain sensitivity;
- inhibition of reflexes;
- loss of consciousness;
- coma.
Hypothermia treatment
If due to hypothermia there was a violation of the thermoregulation of the body, treatment should be aimed at increasing body temperature. With a mild form of hypothermia, it is enough to perform the following actions:
- go to a warm room;
- drink hot tea;
- rub your feet and put on warm socks;
- take a hot bath.
If it is not possible to quickly get into the heat, you need to start active movements - jumping, rubbing your hands (only not with snow), clapping, any physical exercises.
First aid in case of violation of thermoregulation of the second, and especially the third degree, should be provided by the closest people, since the victim himself can no longer take care of himself. Action algorithm:
- move a person to heat;
-quickly take off his clothes;
- lightly rub the body;
- wrap in a blanket, and preferably in a fabric that does not let air through;
- if the swallowing reflex is not disturbed, drink warm liquid (tea, broth, water, but not alcohol!).
If possible, you need to call an ambulance and take the patient to a hospital, where treatment will be carried out using antispasmodics, analgesics, antihistamines and anti-inflammatory drugs, vitamins. In some cases, resuscitation is carried out, sometimes frostbitten limbs have to be amputated.
In children, the occurrence of hypothermia is observed especially often. In case of hypothermia, they need to be warmed by wrapping, give breasts or warm milk. An excellent tool that stimulates thermoregulation is hardening, which parents should carry out for the baby from the first months of life. In the initial stages, it consists in air baths and walks in the fresh air. Later, wiping the legs with a wet cloth, washing with cool water, bathing with a gradual decrease in water temperature, and walking barefoot are added.
Hyperthermia
The rise in body temperature or hyperthermia almost always causes a violation of the body's thermoregulation. The reasons may be as follows:
- many diseases (trauma, infection, inflammation, vegetovascular dystonia);
- prolonged exposure to the sun;
- clothes that prevent sweating;
- stress;
- increased physical activity;
- overeating.
If the patient shows signs of anydiseases (cough, gastrointestinal disorders, complaints of pain in the organs and others), he must perform a series of diagnostic studies to identify the cause of the temperature increase:
- blood test;
- urinalysis;
- X-ray;
- ECG;
- Ultrasound.
Having made a diagnosis, the identified disease is treated, which simultaneously restores body temperature to normal values.
If, due to overheating, there was a violation of thermoregulation, the treatment consists in creating conditions for the victim to restore the functioning of the body systems. Symptoms of sunstroke include:
- general malaise;
- headache;
- nausea;
- rising temperature;
- increased perspiration;
- sometimes convulsions, blackouts and nosebleeds.
The victim should be placed in a cool place (it is advisable to lay down and raise the legs) and:
- strip if possible;
- wipe the body with a damp cloth;
- put a cold compress on the forehead;
- drink cool s alted water.
Heat stroke comes in three types of intensity:
- mild (body temperature slightly elevated);
- medium (t=39°C to 40°C);
- heavy (t=41°C to 42°C).
The mild form is manifested by headache, weakness, fatigue, rapid breathing, tachycardia. As a treatment, you can take a cool shower, drink mineral water.
Violation of thermoregulation of the human body in the middle form is manifested by the following symptoms:
- weakness;
- nausea to vomiting;
- headache;
- tachycardia;
- sometimes loss of consciousness.
Severe symptoms:
- confused mind;
- convulsions;
- frequent thready pulse;
- frequent, shallow breathing;
- deaf heart tone;
- skin hot and dry;
- anuria;
- delusions and hallucinations;
- change in blood composition (decrease in chlorides, increase in urea and residual nitrogen).
In moderate and severe forms, intensive therapy is carried out, including injections of "Diprazine" or "Diazepam", according to indications, the introduction of analgesics, antipsychotics, cardiac glycosides. Before the arrival of the ambulance, the victim must be undressed, wiped with cold water, put ice in the groin, armpits, forehead and back of the head.
Thermoregulation disorder syndrome
This pathology is observed with dysfunction of the hypothalamus and can manifest itself as hypo- and hyperthermia.
Reasons:
- congenital pathologies;
- tumor;
- intracranial infection;
- exposure to radiation;
- bulimia;
- anorexia;
- malnutrition;
- an excess of iron.
Symptoms:
- patients equally poorly withstand both cold and heat;
- constantly cold extremities;
- during the day the temperature remains unchanged;
-subfebrile temperatures do not respond to antibiotics, glucocorticoids;
- lowering the temperature to normal values after sleep, after taking sedatives;
- connection of temperature fluctuations with psychoemotional stress;
- other signs of hypothalamic dysfunction.
Treatment is carried out depending on the causes that caused problems with the hypothalamus. In some cases, it is enough to prescribe the right diet to the patient, in others hormone therapy is required, and in others, surgical intervention.
The chill syndrome also indicates a violation of thermoregulation. Those who have this syndrome are constantly cold, even in summer. In this case, the temperature is often normal or slightly elevated, low-grade fever lasts a long time and monotonously. Such people may experience sudden pressure surges, increased heart rate, respiratory disorders and excessive sweating, and disturbed drives and motivations. Studies show that a disorder in the autonomic nervous system is the cause of the chill syndrome.
