Heatstroke

Heat stroke or hyperthermia is a serious disorder of neurological and general functions of the human body, which occurs as a result of overheating of the whole 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 the change in temperature 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 of a life-compatible external temperature, then the signals coming to the central nervous system control the process of thermoregulation. When the external environment in the full sense of the word heats up, the increased 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, and 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, often to hypovolemic shock and general intoxication.

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Causes of heat stroke

There are two explanations for heat stroke:

1. Intense thermal exposure – cumulative or sudden, spontaneous.
2. Insufficient speed of adaptation of the human body to elevated temperatures from the external environment.

General 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 heat production by the body.
• Constantly working hard or doing physical exercise.
• Exogenous factor – increased ambient temperature.
• Combination of exogenous and endogenous factors.

Combination of one of the causes with alcohol, drugs External causes of heat stroke (exogenous) Internal causes of heat stroke (endogenous) High air humidity Severe dehydration Clothing that creates a "greenhouse" effect, too warm, closed Impaired central nervous system functions High external temperature, abnormal heat Cardiological pathologies Taking medications as a course of therapy or on your own initiative (amphetamines, tricyclic antidepressants, MAO inhibitors). Weather sensitivity, poor ability to acclimatize Alcohol intake Overweight, obesity

Most often, heat strokes occur in countries with a hot climate, and not among the local population, but among people who have arrived there for various purposes. Also, cases of hyperthermia are not uncommon in complex industries associated with elevated indoor temperatures. If workers do not have adequate special clothing, the ability to take short breaks, heat stroke is inevitable. Children, pregnant women, and people aged 55 and above are extremely vulnerable to intense heat exposure. People with anhidrosis or hyperhidrosis are also a risk group in terms of possible heat stroke.

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Pathogenesis of heat stroke

The stages of hyperthermia pathogenesis are links in the disruption of water-electrolyte balance and homeostasis of the body due to excessive heat accumulation. The change in balance develops as a result of hyperhidrosis or anhidrosis, as well as due to the loss of control of thermoregulation by the higher vegetative center - the hypothalamus.

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

1. Overheating of the body initially goes through a short-term compensation phase, when the body tries to cope with the heat problem on its own.
2. An attempt at compensatory actions with obviously unequal resources leads to a serious breakdown of the thermoregulation mechanism.
3. Violation of the thermoregulation function leads to an increasing increase in body temperature, which strives to balance its indicators with the temperature of the external environment.
4. The stage of decompensation develops with simultaneous rapid depletion of adaptation mechanisms.
5. In severe forms, heat stroke is accompanied by general intoxication of the body, acidosis, DIC syndrome, renal failure, heart failure due to rapid dystrophic changes in the myocardium. Pulmonary edema or cerebral hemorrhage are also possible.

Laboratory tests of serum and blood show:

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

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

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

The pathogenesis of severe heat stroke ends with the cessation of respiratory functions, cessation of energy supply to brain tissue, its swelling, and death.

Signs of heat stroke

The clinical picture of heat stroke depends on several factors:

• Intensity of thermal exposure.
• Duration of exposure to heat.
• Age of a person.
• Diseases of internal organs and systems.
• Individual characteristics – weather sensitivity, allergies.
• Taking medications that provoke symptoms (medicines, narcotics, alcohol).

Signs of heat stroke are especially acute and intense in people suffering from the following pathologies:

• Cardiovascular diseases, recent myocardial infarction or stroke, heart defects.
• Hypertension.
• Thyroid diseases.
• Vegetative-vascular syndrome.
• Diabetes mellitus.
• Hormonal dysfunctions.
• Bronchial asthma.
• Allergy.
• Metabolic disorder, overweight or anorexia.
• Hepatitis, liver cirrhosis.
• Neuropsychiatric diseases.

Symptoms also develop rapidly in children under 6-7 years of age, elderly people, and pregnant women.

Signs of stage 1 hyperthermia:

• Rapidly increasing weakness, a desire to lie down and fall asleep.
• The headache is dull and aching.
• Feeling of nausea.
• A feeling of heaviness in the chest, a desire to breathe in, to yawn.
• Dilation of the pupils.
• Paleness of the skin.
• Hyperhidrosis.
• Body temperature usually does not rise.

Symptoms of stage II hyperthermia:

• Feeling of immobility, myasthenia. Difficulty moving, raising arms, head.
• Intense headache - diffuse, non-localized.
• Nausea, vomiting.
• Noise in the ears, ringing sensation.
• Dynamic and static ataxia (impaired coordination of movements).
• Tachycardia, increased heart rate.
• Dehydration.
• Intermittent, rapid breathing.
• Increase in body temperature up to 40 degrees.
• Fainting.

Signs of heat stroke of the third degree of severity:

• A sharp increase in body temperature (pyretic temperature).
• No urination.
• The skin changes color dramatically, from hyperemia to cyanosis.
• Shallow breathing.
• Threadlike pulse.
• Desire to move, psychomotor agitation, convulsive urges to stand up.
• Clonic-tonic seizures.
• Delusional state, hallucinations – visual, auditory, kinesthetic.
• Stupor, coma.

Mild and moderate heat stroke is well managed with timely medical care. Severe hyperthermia is fatal in 25-30% of cases.

Fainting and heat stroke

Fainting is a condition of short-term loss of consciousness due to sudden development of cerebral anemia (circulatory disorders). Among other causes, fainting is provoked by heat stroke, which occurs in both adults and children. Loss of consciousness can be sudden, but it can also be preceded by certain symptoms - weakness, lethargy, dizziness, ophthalmological disorders (double vision, "floaters"), noise or ringing in the ears, cold sweat. In humans, a pre-fainting condition is manifested by characteristic signs - pale face, impaired coordination of movements. Sometimes, at the first symptoms, it is enough to lay the patient in a horizontal position, ensure blood flow to the brain to prevent fainting. Moderate heat stroke often manifests itself in fainting due to vascular disorders and oxygen starvation.

What can be done if heat stroke is accompanied by fainting?

• Lay the person down with his legs raised and his head slightly lowered.
• If it is not possible to lay the patient horizontally, he should be seated and his head should be lowered down to his knees.
• Unbutton the top buttons of your clothing, and if possible, remove your clothing altogether, allowing air to reach your skin.
• Apply cold compresses to your temples.
• If you have ammonia, soak a tampon, cotton wool, or handkerchief in alcohol and hold it to the victim’s nose.
• You can gently pat the victim on the cheeks, ensuring blood flow to the head. You can also try massaging the auricles.
• When the victim comes out of a state of fainting, you need to give him sweet tea.
• You should not experiment with coffee, strong tea, or alcohol if fainting is caused by heat stroke and not other reasons.
• If loss of consciousness recurs, seek emergency medical attention.

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Heatstroke in children

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

What causes heat stroke in children?

First of all, adults, i.e. parents, are responsible for a child's hyperthermia. It is a caring mother who can wrap up her baby so much in the hot season that even in the absence of the sun, the child gets heat stroke. In addition, long walks, no headgear, synthetic clothing, excessive passion for staying on sea beaches, a stuffy, poorly ventilated room - all these are factors that provoke thermal hyperthermia. There are also reasons that parents cannot influence - this is high air humidity, abnormal heat, however, these natural phenomena can be minimized with the help of ventilation, reasonable air conditioning and other measures.

How does heat stroke manifest itself in a child?

Signs of hyperthermia depend on the severity of the thermal factor and may be as follows:

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

Heat stroke in children is easy to notice, even if its development is latent, the baby's body reacts almost instantly to a violation of thermoregulation. The only problem is the clinical picture of thermal hyperthermia in newborns, since they are unable to complain of either headache or nausea. However, frequent regurgitation, increased body temperature, incessant crying, lethargy, cyanosis of the skin, cold sweat and constant yawning will help to determine the symptoms of heat stroke.

What should parents do?

1. Call a doctor.
2. Before medical help arrives, place the child in the coolest possible room, in the shade.
3. The child should lie with his head raised and turned to the side so that vomit does not cause suffocation.
4. The child should be undressed and provided with access to cool air to the body. Small children should not even have a diaper on their body.
5. A cloth soaked in cool (not cold) water should be placed on the forehead.
6. The baby needs plenty of fluids to neutralize dehydration. It is advisable to give purified water, but the best option is a pharmacy drug - Regidron.
7. The baby's body should be wiped as often as possible. This can be a cloth soaked in water, a weak vinegar solution will also work.
8. Babies under one year old can be wrapped in a diaper soaked in warm water.

Parents should be aware of the dangers of heat stroke and its threatening consequences, and safety measures are quite simple:

• During hot seasons, it is necessary to ensure access of air to the room (ventilation).
• A child's clothing should correspond to the season, and not to the concerns of an overly caring mother.
• When outside, the child's head should be covered with a sun hat.
• At temperatures above 27 degrees, walks should be no more than 30-40 minutes, preferably in a shady area.
• During hot weather, a child should have an increased drinking regimen.
• At the first alarming signs that indicate heat stroke in children, you need to seek medical help.

Forms of heat stroke

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

1. Asphyxia. The asphyxic form develops against the background of an increase in the temperature of the external environment, hyperthermia of the body, when all functions of the central nervous system slow down, the respiratory function is disrupted and suppressed.
2. High body temperature – pyretic form, when the temperature reaches 39-41°.
3. Paralytic or cerebral form, when, against the background of hypoxia and hyperthermia (pyretic temperature), convulsions develop, delirium and hallucinations are possible.
4. Dyspeptic or gastroenteric form, when vomiting and diarrhea develop with urinary retention.

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

1. A mild form of hyperthermia is accompanied by rapid breathing, increased heart rate, headache, weakness and nausea.
2. Moderate heat stroke is myasthenia (muscle weakness), intense headache, nausea, leading to vomiting. Possible loss of coordination, fainting. Hyperthermia in this form occurs 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 seizures, paralysis, delirium. Breathing becomes intermittent, rapid, the 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.

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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 assistance and prevent the development of threatening symptoms.

Treatment of heat stroke involves the following measures:

1. Move the victim to a shaded, cool place as soon as possible.
2. Remove clothing, leaving only the bare minimum.
3. Apply a cool (not ice) compress to the forehead. Important note: ice and very cold water are strictly contraindicated in case of heat stroke, as their contrast action will provoke vascular collapse. Cool compresses can also be applied to the carotid artery area, chest, hands, calves, groin area, popliteal parts, armpits.
4. The victim needs to drink plenty of fluids – purified water, still mineral water, weak tea with sugar.
5. If vascular symptoms or convulsions occur, professional medical assistance is provided; self-medication is unacceptable. The only thing that can be done is to stimulate cardiac activity (give validol, cordiamine, corvalol).

Treatment of heat stroke also involves independent resuscitation measures – external cardiac massage or artificial respiration (often this is done together).

What to do in case of heat stroke?

Actions in case of heat stroke can be reduced to three main measures:

• Cooling the victim's body.
• Neutralization of dehydration.
• Call an ambulance if symptoms are threatening.

What to do in case of heat stroke should be known first of all by parents of small children, although such information will not be superfluous for all other lovers of being in the sun. Any available means will do to cool an overheated person:

• Compresses - the cloth is moistened with cool water, but in no case ice-cold. The temperature contrast can aggravate the symptoms and provoke vascular problems.
• General cooling by immersing the victim's body in a bath of water or in sea or river water is also suitable.
• Cooling the body involves exposing it as much as possible. Clothing should be removed to the limits determined by decency.
• It would not be a bad idea to fan the victim with any available materials that can act as a fan.
• Systematic rubbing of the body can also reduce hyperthermia. You can use a weak solution of vinegar or just water.
• Every 20-30 minutes the victim should be given non-carbonated mineral water, weak tea with sugar or a solution of Regidron to drink.
• If heat stroke causes vascular disorders - fainting, convulsions, immediate medical care is needed. Before its arrival, you can give the patient 15-20 drops of tincture of valerian, cordiamine or corvalol. If necessary, perform indirect cardiac massage.

There is a proven "home" resuscitation method. You need to squeeze the victim's little fingers as hard as possible (on the sides of the nail plate). Rhythmic, strong pressure on these points helps to restore cardiac activity, at least for a while.

First aid for heat stroke

First aid for heat stroke consists of clear, confident actions that need to be taken as quickly as possible.

Usually the victim himself tries to lie down, people around him need to make sure that the patient's head is slightly lowered and his legs are raised. It is better to turn the head to the side, so that in case of vomiting, to prevent vomit from getting into the throat. Of course, all actions that help the patient recover should be carried out in a cool, shady place. It is better if it is a ventilated room. It is imperative to give the person any purified, neutral liquid to drink. It is unacceptable to drink alcohol, strong tea or coffee, carbonated water, juices, fermented milk products are not suitable. Plain water, boiled or purified, will be much more useful than compote or kefir. Rubbing with cool water helps well, it is even better if compresses are applied to places where large vessels pass. These are the following areas:

• Forehead.
• Neck.
• Submandibular zones.
• Whiskey.
• Clavicles.
• Inner areas of the elbows.
• Areas under the knees.
• Calves of the legs.
• Groin.
• Sacrum.

Avoid sudden, contrasting cooling, as well as hypothermia. The water used to moisten the compress can be within 18-22 degrees. If you have ammonia at hand, you can bring a cotton ball soaked in this solution to the victim's nose. Sweet tea and water with sugar will also help - this will maintain the level of energy supply to the brain. The following remedy is also effective: add a tablespoon of salt, two tablespoons of sugar, a teaspoon of orange or lemon juice (a tablet of soluble aspirin will do) to 1 liter of boiled cooled water. The victim needs to drink at least 1.5 liters of this solution over 5-6 hours in small sips with a break of 10 minutes.

More professional assistance, if required by the condition of the injured person, will be provided by doctors. And pre-hospital care for heat stroke will help the patient not to lose consciousness and will slightly stop the development of hyperthermia symptoms.

Prevention of heat stroke

The severity of heat stroke can be avoided if safety measures are taken in a timely manner. Although it is impossible to influence weather conditions, a person has ways to protect himself from both rain and heat.

• During the hot summer period, you need to make sure that your wardrobe contains only clothes made from natural materials.
• When working in conditions that involve increased heat (factories, confectionery shops, kitchens, construction sites, etc.), you need to take care of comfortable work clothes. In addition, you should take short breaks of 3-5 minutes every hour to provide your body with moisture. This drinking regime will help normalize the thermoregulation process.
• Home premises should be regularly ventilated or a high-quality air conditioner should be installed.
• Drinking plenty of fluids will help reduce the risk of dehydration, and therefore the risk of heatstroke.
• In very hot weather, physical overload should be avoided. If you have the opportunity to choose your own work schedule, you should prefer morning and evening hours. It is no coincidence that in hot countries there is a siesta time, it falls exactly at the peak of high air temperature.
• You should not spend a lot of time in hot air, especially if you are walking with small children.
• Both adults and children should wear light headgear.

Preventive measures do not require any special efforts or costs, you just need to remember them and follow them, and hot weather is in any case a temporary phenomenon and in the fall you can forget about heat strokes.