Heatstroke

Hyperthermia from heat exposure or heat stroke is a serious violation of the neurological and general functions of the human body, resulting from overheating of the entire body. Hyperthermia develops very quickly, sometimes to critical values of 42-43 degrees in rectum (in the rectum), as a result the body does not have time to adapt to temperature changes and there is a rapid depletion of compensatory properties.

Thermoregulation of the human body is possible at a normal internal temperature of about 37 °, fluctuations within 1.5 degrees are permissible. If the thermoreceptors of the skin and all mucous membranes work normally, and this is possible only under the condition that the external temperature is compatible with life, then the signals entering the central nervous system control the process of thermoregulation. When the external environment is heated in the full sense of the word, the elevated temperature changes the mechanism of heat transfer of the human body, there is a violation of the speed and completeness of blood flow, vascular regulation, the tone of the vessels changes. In addition, the heat provokes intense sweating, which sometimes reaches record levels - 1, 5 liters per hour. Such a rapid loss of fluid inevitably leads to dehydration (dehydration), often to hypovolemic shock and general intoxication.

[1], [2]

Causes of heatstroke

There are two explanations for heat stroke: 

1. Intensive thermal effect - cumulative or sudden, spontaneous.
2. Insufficient rate of adaptation of the human body to an increased temperature from the external environment.

Common factors, causes of heat stroke can also be divided into two categories - endogenous (internal) and exogenous (external): 

• An internal factor associated with chronic diseases that provoke an increase in body heat production.
• Constant hard work or doing physical exercises.
• Exogenous factor - increased ambient temperature.
• Combination of exogenous and endogenous factors.

Combination of one of the causes with the use of alcohol, drugs External causes of heat stroke (exogenous) Internal causes of heat stroke (endogenous) Increased air humidity Strong dehydration (dehydration) Clothes creating a "greenhouse" effect, too warm, closed Disturbance of central nervous system functions High temperature of the environment, abnormal heat Cardiac pathology Acceptance of medications as course therapy or on their own initiative (amphetamines, tricyclic antide ressanty, MAO inhibitors). Meteosensitivity, poor ability to acclimatize Alcohol intake Overweight, obesity

Most often, heat shocks occur in countries with a hot climate, and not from the local population, but from people who arrived there with different purposes. Also, cases of hyperthermia in complex industries associated with high temperature in the room are not uncommon. If workers do not have adequate overalls, the opportunity to take short breaks, a heat stroke is inevitable. Children, pregnant women, people aged 55 and above are extremely vulnerable to intense heat exposure. People with anhidrosis or hyperhidrosis are also a risk group in the sense of a possible heat stroke.

[3],

The pathogenesis of heat stroke

Stages of the pathogenesis of hyperthermia are the links of the disturbance of the water-electrolyte balance and the homeostasis of the organism due to excessive heat accumulation. The change in balance develops as a result of hyperhidrosis or anhidrosis, and also because of loss of control of thermoregulation from the higher vegetative center - the hypothalamus.

The pathogenesis of heat stroke depends on the state of human health and on the intensity of external factors. In general, the development of the pathological syndrome can be described as follows: 

1. Overheating of the body initially passes a short-term compensation stage, when the body tries to cope with the heat problem on its own.
2. Attempting compensatory actions with obviously unequal resources leads to a serious breakdown in the mechanism of thermoregulation.
3. Violation of the function of thermoregulation leads to an increase in body temperature, which tends to balance its performance with the temperature of the external environment.
4. The stage of decompensation is developing with simultaneous rapid depletion of adaptation mechanisms.
5. In severe forms, heat stroke is accompanied by general intoxication of the body, acidosis, DVS - syndrome, renal insufficiency, heart failure due to rapid dystrophic changes in the myocardium. Also, pulmonary edema or cerebral hemorrhage is possible.

A laboratory study of serum and blood shows: 

1. Blood - thrombocytopenia, leukocytosis, hypofibrinogenemia.
2. Urine - cylindruria, leukocyturia, proteinuria.

The developing process of general intoxication is most dangerous in that it leads to heart failure, the pathogenesis of which looks like this: 

• A sharp drop in blood pressure.
• Sharp decrease in speed and filling of blood flow.
• Increasing venous pressure.
• Renal failure.
• Decreased microhemocirculation.
• Rapid development of dystrophic changes in the tissues of the heart muscles.
• Acidosis.
• Circulatory hypoxia.

The pathogenesis of a heat stroke of severe form results in the cessation of respiratory functions, the stopping of energy supply to the brain tissues, its edema, and fatal outcome.

Symptoms of heat stroke

The clinic of heat stroke depends on several factors: 

• Intensity of heat exposure.
• Duration of exposure to heat.
• Age of the person.
• Disease of internal organs and systems.
• Individual characteristics - meteosensitivity, allergy.
• Reception of symptomatic provoking drugs (drugs, drugs, alcohol).

The signs of heat stroke are especially acute and intense in people suffering from such pathologies: 

• Cardiovascular disease, recently suffered myocardial infarction or stroke, heart disease.
• Hypertension.
• Diseases of the thyroid gland.
• Vegeto-vascular syndrome.
• Diabetes.
• Hormonal dysfunction.
• Bronchial asthma.
• Allergy.
• Metabolic disorders, overweight or anorexia.
• Hepatitis, liver cirrhosis.
• Neuropsychiatric diseases.

Also, symptomatology develops rapidly in children aged 6-7 years, the elderly, pregnant women.

Signs of hyperthermia I degree: 

• Rapidly growing weakness, there is a desire to lie down, fall asleep.
• Headache - dull, aching.
• Feeling of nausea.
• Feeling of heaviness in the chest, a desire to breathe, yawn.
• Dilation of pupils.
• Pale skin.
• Hyperhidrosis.
• Body temperature, as a rule, does not increase.

Symptoms of hyperthermia of the 2nd degree: 

• Feeling of immobility, myasthenia gravis. It is difficult to move around, raise your hands, head.
• Intensive headache - spilled, non-localized.
• Nausea, vomiting.
• Noise in the ears, sensation of ringing.
• Dynamic and static ataxia (impaired coordination of movements).
• Tachycardia, increased heart rate.
• Dehydration.
• Intermittent, rapid breathing.
• Raise body temperature to 40 degrees.
• Fainting.

Symptoms of thermal shock III degree of severity: 

• A sharp rise in body temperature (pyretic temperature).
• Absence of urination.
• The skin changes color sharply - from hyperemia to cyanosis.
• Superficial breathing.
• Threadlike pulse.
• Desire to move, psychomotor agitation, convulsive impulses to get up.
• Clonic-tonic convulsions.
• Delusional state, hallucinations - visual, auditory, kinesthetic.
• Sopor, coma.

The light and medium severity of a heat stroke is well supervised with timely medical care. Severe hyperthermia in 25-30% of cases ends in a lethal outcome.

Fainting and heat stroke

A syncope is a state of short-term loss of consciousness due to sudden anemia of the brain (circulatory disorders). In addition to other causes, a heat stroke provokes fainting, which happens in both adults and children. Loss of consciousness may be sudden, but it may also be preceded by some symptoms - weakness, lethargy, dizziness, ophthalmic disorders (double vision, "flies"), noise or ringing in the ears, cold sweat. In man, the pre-fainting condition is manifested by characteristic signs - pallor of the face, disruption of coordination of movements. Sometimes, with the first symptoms, it is enough to put the patient in a horizontal position, to ensure the flow of blood to the brain in order to prevent fainting. Heat stroke of moderate severity is often manifested by syncope due to vascular disorders and oxygen starvation.

What can be done if a heat stroke is accompanied by a faint? 

• Put a man, lifting his legs, and lower his head slightly.
• If there is no possibility to put the patient horizontally, it should be planted and lowered head down to the knees.
• Unbutton the upper buttons of clothing, if possible, remove clothing at all, ensuring air access to the skin.
• Attach cool compresses to temples.
• If there is ammonia, moisten with alcohol a swab, cotton wool, a handkerchief and bring it to the victim's nose.
• You can gently pat the victim on the cheeks, ensuring the flow of blood to the head. You can also try to massage your ears.
• When the victim leaves the state of fainting, you need to give him sweet tea.
• You should not experiment with coffee, strong tea, alcohol, if syncope is caused by heat stroke, and not by other causes.
• If a loss of consciousness is repeated, you should call for emergency medical attention.

[4], [5]

Heat stroke in children

The hot season is especially hard for infants and toddlers up to 3-4 years old. This is due to the fact that the child has not yet fully formed the mechanism of thermoregulation and the general metabolism of the body. It is children who suffer most from dehydration and intoxication, so the heat stroke in children is a serious, pathological condition that threatens not only health but also life.

What triggers heat stroke in children?

First of all, adults are responsible for hyperthermia of the child, that is, parents. It is a caring mother can so wrap her baby in the hot season, that even in the absence of the sun, the child receives a heat stroke. In addition, long walks, lack of a headdress, synthetic clothing, excessive interest in staying on seaside beaches, stuffy, poorly ventilated room - all these are factors that provoke thermal hyperthermia. There are also reasons that parents can not influence - it is high humidity, abnormal heat, however these natural phenomena can be minimized by airing, reasonable conditioning and other activities.

How does the child's heat stroke manifest?

The signs of hyperthermia depend on the severity of the effect of the thermal factor and can be as follows: 

1. A slight heat stroke is manifested by complaints of a headache, nausea, lethargy. The kid is capricious, loses his appetite, refuses to play, tries to lie down. The pulse of the child is more frequent, the pupils can be dilated, the face turns red. The baby's skin is hot to the touch, sweaty, although body temperature, as a rule, does not rise above 37 degrees. In this form, heat stroke in children is often manifested by nosebleeds, vomiting. 
2. The average severity of the stroke is also manifested by lethargy, poor health, headache. However, if the child tries to get up and walk around the room, the attentive parent will immediately notice the unsteadiness of the gait, the violation of coordination of movements. The baby often vomits, the body temperature rises to 39 degrees, it is difficult for him to breathe, a syncope is possible. 
3. A severe form of heat stroke in a child with caring parents should not be in principle. Nevertheless, it looks like a febrile state, body temperature is raised to critical values (40-41 degrees), convulsive syndrome develops, a coma is possible.

Heat stroke in children is easy to see, even with its hidden development, the baby's organism almost instantly reacts to the violation of thermoregulation. The only problem is a clinic of thermal hyperthermia in newborns, because they are not able to complain of either headache or nausea. However, frequent regurgitation, increased body temperature, non-stop crying, lethargy, cyanosis of the skin, cold sweat and constant yawning will help to determine the symptomatology of heat stroke.

What should parents do?

1. Call a doctor.
2. Before the arrival of medical care, place the child in the coolest possible place, in the shade.
3. The child should lie with his head raised, turned to one side, so that vomit would not provoke gasps.
4. The baby needs to be undressed and provide cool air to the body. Young children should not even have a diaper on their body.
5. On the forehead, you should put a cloth soaked in cool (not cold) water.
6. The baby needs a copious drink to neutralize dehydration. It is advisable to give purified water, but the best medicine is the drug - Regidron.
7. As often as possible, you need to wipe the body of the baby. It can be a cloth soaked in water, a weak vinegar solution will also work.
8. Babies up to a year can be wrapped in a diaper, soaked in warm water.

Parents should be aware of the danger of a heat stroke and its threatening consequences, and the security measures are fairly simple: 

• In the hot season it is necessary to provide air access to the room (ventilation).
• The child's clothing should match the season, and not the worries of an overly caring mother.
• On the street the child's head should be covered with panama.
• At an air temperature of over 27 degrees, walks should be no more than 30-40 minutes, preferably in a shady area.
• In hot season, the child should have an intensified drinking regimen.
• At the first alarm signs, which indicate a heat stroke in children, you need to seek medical help.

Forms of heatstroke

In clinical practice, heat stroke is divided into the following forms: 

1. Asphyxia. The asphyctic form develops against the background of an increase in the temperature of the external environment, hyperthermia of the body, when all the functions of the central nervous system slow down, respiratory function is disrupted and depressed.
2. High body temperature is a pyretic form when the temperature reaches 39-41 °.
3. Paralytic or cerebral form, when hypoxia and hyperthermia (pyretic temperature) develop seizures, there may be delusions and hallucinations.
4. Dyspeptic or gastroenteric form, when vomiting and diarrhea develop with delayed urination.

Also, the forms of heat stroke differ in the severity of the hyperthermic process: 

1. A mild form of hyperthermia occurs with rapid breathing, acceleration of heartbeats, headache, weakness and nausea. 
2. Heat stroke of moderate severity is myasthenia gravis (muscle weakness), intense headache, nausea, and vomiting. Possible violation of coordination of movements, fainting. Hyperthermia in this form is accompanied by tachycardia, an increase in body temperature to 39-40 ° C, hyperhidrosis. 
3. The most dangerous is the severe degree of hyperthermia, when all the symptoms of the cerebral form appear - clonic-tonic convulsions, paralysis, delirium. Breathing becomes intermittent, rapid, pulse reaches 120 beats per minute, characteristic cyanosis of the skin develops, pyretic temperature - up to 41 ° C, all reflexes are weakened. This condition often ends in coma and death.

[6], [7],

Treatment of heat stroke

Treatment of thermal hyperthermia is a clear algorithm of actions that you need to know in order to be able to provide timely help and prevent the development of threatening symptoms.

Treatment of heat stroke involves such measures: 

1. As soon as possible, move the victim to a shade, in a cool place.
2. Remove clothes, leaving only the minimum required.
3. On the forehead apply a cool (not ice) compress. An important point: ice and very cold water are strictly contraindicated in case of a thermal shock, as they will provoke a vascular collapse by their contrast action. Cool lotions can also impose a region of the carotid artery, on the chest, hands, legs calves, inguinal region, popliteal parts, armpits.
4. The victim needs a copious drink - purified water, mineral non-carbonated water, weak tea with sugar.
5. With the manifestation of vascular symptoms, seizures are professional medical care, self-medication is unacceptable. The only thing that can be done is to stimulate cardiac activity (give Validol, Cordiamin, Corvalol).

Treatment of a heat stroke also involves carrying out independent resuscitation measures - external cardiac massage or artificial respiration (often it is done together).

What to do with a heat stroke?

Actions with a thermal shock can be reduced to three main activities: 

• Cooling the body of the victim.
• Neutralization of dehydration.
• Emergency call for threatening symptoms.

What to do with a thermal shock should first of all know the parents of young children, although such information will not be superfluous for all other lovers of sun exposure. To cool an overheated person any convenient means: 

• Compresses - the cloth is moistened with cool water, but in no case is not ice. The contrast of temperatures can aggravate the symptoms and provoke vascular troubles.
• Suitable and general cooling by immersing the body of the victim in the bathroom with water or in the sea, river water.
• Cooling the body assumes its maximum outcrop. Clothing should be removed to the decency of the boundaries.
• It will not be superfluous to fan the victim with any improvised materials that can perform the role of a fan.
• Systemic body wiping also can reduce hyperthermia. You can use a weak solution of vinegar or just water.
• After every 20-30 minutes, the victim should be given a drink of mineral non-carbonated water, a weak tea with sugar or a solution of Regidron.
• If a heat stroke causes vascular disorders - fainting, convulsive conditions, immediate medical attention is needed. Before her arrival, you can give the patient 15-20 drops of tincture of valerian, cordiamine or corvalol. If necessary, conduct an indirect massage of the heart. 

There is a proven "home" resuscitation method. It is necessary as much as possible to squeeze the little fingers of the affected person (on the sides of the nail plate). Rhythmic, strong pressure on these points help at least temporarily restore cardiac activity.

First aid for heat shock

First aid for a heat stroke consists in clear, confident actions that need to be carried out as soon as possible.

Usually the victim himself tries to lie down, the people around him should make sure that the patient's head is slightly lowered and the legs are raised. The head should be turned on its side, in case of vomiting, do not let vomit fall into the throat. Of course, all actions that help the patient to recover, should be conducted in a cool, shady place. It is better if it is a ventilated room. It is necessary to give a drink to a person with any purified, neutral liquid. It is unacceptable to take alcohol, strong tea or coffee, do not fit aerated water, juices, sour-milk products. Ordinary water, boiled or purified will have much more benefit than compote or kefir. Good help rubs with cool water, even better, if the places where large vessels pass, compresses will be applied. These are the areas: 

• Forehead.
• Neck.
• Submandibular zones.
• Whiskey.
• The clavicles.
• Inner areas of elbows.
• Areas under the knees.
• Caviar of legs.
• Groin.
• Sacrum.

It is impossible to allow sharp, contrast cooling, as well as supercooling. Water, which is moistened with a compress, can be in the range of 18-22 degrees. If you have ammonia at hand, you can bring a cotton wool soaked in this product to the nose of the victim. Help and sweet tea, water with sugar - this will support the level of energy supply to the brain. Also effective is the intake of the following remedy: 1 liter of boiled chilled water is added with a tablespoon of salt, two tablespoons of sugar, a teaspoon of orange or lemon juice (a tablet of soluble aspirin is suitable). The victim should drink at least 1, 5 liters of this solution for 5-6 hours in small sips with a break of 10 minutes.

More professional help, if required by the condition of the injured person, will be provided by doctors. A pre-hospital help with a thermal shock will help the patient do not lose consciousness and a little stop the development of symptoms of hyperthermia.

Prevention of heat stroke

The severity of a heat stroke can be avoided if the safety measures are taken in a timely manner. Despite the fact that it is impossible to affect weather conditions, a person is protected by ways of protection from both rain and heat.

• In the hot summer period, care must be taken to ensure that the wardrobe has clothes made only of natural materials.
• When working in conditions that involve an increased thermal regime (factories, confectionery shops, kitchens, construction, etc.), you should take care of comfortable overalls. In addition, in the work should be a short break for 3-5 minutes every hour to provide your body with moisture. It is this drinking regime that will help to normalize the process of thermoregulation.
• Household premises should be regularly ventilated, or install a high-quality air conditioner.
• Abundant drink will help reduce the risk of dehydration, and, therefore, the risk of heat stroke.
• If the weather is too hot, physical overload should be avoided. If there is an opportunity to choose the operating mode independently, morning and evening hours should be preferred. It is no accident in hot countries there is a siesta time, it just falls on the peak of high air temperature.
• Do not spend too much time in the hot air, especially if you are walking with young children. 
• On the head and in adults, and children should have light headgear.

Prevention measures do not require special efforts or expenses, they simply need to be remembered and observed, and hot weather in any case is a temporary phenomenon and it will be possible to forget about heat strikes in the fall.