Intense physical activity produces heat at an incredible rate, with marathon runners producing more than 1,000 kilocalories per hour. At this rate of heat production, if the body cannot dissipate heat, the body temperature will rise by one degree Celsius every two minutes, and after ten minutes it will reach a body temperature that is sufficient to cause heat damage to cells in various organs of the body, that is, heat stroke. Therefore, in situations where the body is not dissipating heat, such as a hot, humid and windless environment, clothing that is not breathable, a medical condition that reduces perspiration such as dehydration, or medications such as antihistamines, less intense exercise can also be used in Causes heat stroke after a long time. Exposure to ambient heat without effective heat loss can lead to heat cramps, heat stroke, or heat exhaustion. Acute (eg, intense exertion for 3 to 4 hours) or prolonged (10 to 12 days) exposure to high temperatures and excessive sweating without compensation for fluid intake can lead to dehydration, sodium and potassium deficiency, and hypoglycemia capacity. Concomitant vomiting and diarrhea can in turn promote fluid loss. Evaporation is the most important source of heat dissipation, but it depends on relative humidity: heat dissipation is poor at high relative humidity. Thus high ambient humidity (which reduces the cooling effect of sweating) and prolonged vigorous activity (which increases muscle heat production) may increase the risk of hyperthermia damage. Age, obesity, chronic alcoholism, frailty, and many drugs (eg, anticholinergics, antihistamines, phenothiazines, many psychotropic drugs, alcohol, cocaine) can increase damage to heat, especially heat stroke. susceptibility. So outdoor sports drinking is not good.
Classification of high temperature damage by domestic medical community
According to the severity of clinical manifestations , high temperature damage can be divided into threatened heatstroke, mild heatstroke and severe heatstroke, and the relationship between them is gradual.
Severe heat stroke can be further divided into four types: heat cramps, heat exhaustion, sunstroke and heat stroke.
Isn’t it a bit messy to talk about so much. Research on heat damage is rarely done.
1. Let??s talk about heat exhaustion and heat exhaustion first.
Hypovolemia and electrolyte imbalance caused by excessive fluid and electrolyte loss due to prolonged exposure to high temperature environment and profuse sweating.
Exposure to high temperatures, especially during heavy physical labor or physical exercise, causes significant loss of body fluids, along with salt (electrolytes), through sweating. Disturbs the circulatory system and brain, leading to heat exhaustion (collapse), which appears to be severe but rare.
1.1 Diagnosis of heat exhaustion, heat exhaustion
Symptoms and signs
Main symptoms It’s fatigue, weakness, anxiety, and sweating. Because of the heat, the blood vessels of the lower extremities dilate and the blood pools, and it is easy to faint when standing. Slow heartbeat, weak pulse, clammy pale skin, cool and slippery; possible mental disturbance, loss of body fluids, hypovolemia, drop in blood pressure, and possible collapse or fainting. The presence of these symptoms is usually the diagnosis of heat exhaustion.
Excessive sweating without timely fluid replacement can cause heat exhaustion with fatigue, weakness and anxiety. Circulatory collapse followed by a slow, fine pulse; blood pressure low and undetectable; skin cold, pale, and sticky; mental disturbance, followed by shock-like confusion. The core body temperature is between 38.3 and 40.6 ??C. Symptoms of mild heat exhaustion (due to blood pooling in the thermally dilated lower extremity vessels) induced by prolonged standing in a hot environment are subnormothermia and simple syncope.
diagnosis
Heat exhaustion causing circulatory collapse should be associated with insulin shock, toxicity , hemorrhage or traumatic shock. A history of exposure to heat, lack of fluid replacement, no other observable cause, and response to therapy is usually sufficient evidence for diagnosis.
1.2 Prognosis
Unless prolonged circulatory failure, heat exhaustion and heat exhaustion are usually transient and the prognosis is good.
1.3 Treatment
The main treatment is fluid and electrolyte supplementation. Normal blood volume must be restored to ensure adequate cerebral perfusion.
The patient should lie on his back or with his head slightly lowered, and take a small amount of cold water containing slightly salt or an electrolyte drink for athletes every few minutes. Move the patient to a cooler environment.
Intravenous isotonic saline is sometimes required, rarely cardiac stimulants or plasma volume expanders (albumin, dextran); if used, they should be administered with care to avoid volume overload.
After rehydration, patients often recover quickly and completely.
If blood pressure is still low and pulse is slow after 1 hour of treatment, other conditions should be suspected.
2. Heat stroke (sunshot disease; heat stroke fever) — is a ——dangerous——high fever caused by insufficient or impediment of heat dissipation.
Heatstroke is a life-threatening disease caused by people who are in a high temperature environment for a long time and cannot sweat enough to lower their body temperature.
Symptoms usually develop quickly and require immediate attention. If you’re dehydrated and you don’t sweat enough to dissipate heat, your body temperature can rise to dangerous levels, leading to heat stroke. Patients with certain diseases, such as scleroderma and cystic fibrosis, have reduced sweating capacity and an increased risk of heat stroke.
2.1 Diagnosis of Heat Stroke
Symptoms and Signs
Heat stroke develops rapidly. Before the onset of symptoms, sometimes there are auras such as headache, dizziness, and fatigue, but they do not necessarily appear. Usually sweating is reduced. The skin is burning, red, and often dry. The pulse rate increases rapidly, reaching 160 to 180 beats/min; breathing usually increases. But blood pressure is usually rarely affected. The body temperature measured by the anus can rise to 40 ?? ~ 41 ??, and patients often feel “on fire”. A temperature of 41??C is an indicator of severe prognosis, and if it is 1 degree higher, it often causes death.
Temporary disorientation followed by loss of consciousness, coma, or convulsions. ——According to the description of the team members, Ning Qian has suffered disorientation, which should be highly regarded.
There may be circulatory failure before death.
If heatstroke is not treated in time, after several hours of extremely high body temperature, survivors may suffer permanent damage to internal organs such as the brain, often leading to death.
Older, frail patients, and people who drink too much have a worse prognosis.
Heatstroke is usually diagnosed based on exposure to high temperatures, sudden onset of burning, dry, red skin with body temperature >40??C, rapid pulse, and confusion or confusion. Heatstroke should also be distinguished from food, chemical or drug poisoning. Acute infections (eg, sepsis, meningitis) and toxic shock were excluded. Any medications that may contribute to heat stroke should be considered.
2.2 Prognosis of heatstroke
Heatstroke is a life-threatening emergency that can cause convulsions and death if not given prompt and vigorous treatment , permanent brain damage or kidney failure.
A core body temperature of 41??C is a sign of severe prognosis; a slight increase in body temperature is often fatal. Old age, frailty, and alcoholism can worsen prognosis. 2.3 Treatment
For heatstroke, strong first aid measures should be taken immediately. ——If the measures are not timely, people will die.
If far from the hospital, the patient should be removed from the high temperature environment, wrap the patient with wet sheets or wet clothes and use a powerful fan to increase evaporative heat dissipation.
It is also a good idea to wrap the patient in a lake, river, pool, ravine, or even cool them with snow or ice while waiting for transport, applying a wet sheet or wrapping in clothing. If the patient is shaking, the cooling process should be slowed down, because shaking can increase the core body temperature (warning: the body temperature should be measured every 10 minutes, and the body temperature should not be lowered to 38.3 ??, so as to avoid continued cooling and lead to hypothermia).
In the hospital, core body temperature should be continuously monitored to ensure its stability. Avoid stimulants and sedatives, including morphine; avoid excessive cold. If convulsions cannot be controlled, intravenous diazepam and barbiturates can be administered to control convulsions. Electrolytes should be measured frequently to guide intravenous rehydration.
After severe heatstroke, it is best to stay in bed for several days, as body temperature may fluctuate for several weeks.
3. Heatstroke cramps, heat cramps ——striated muscle spasms induced by physical activity due to excessive fluid intake without sodium supplementation.
Striated muscle spasms induced by physical activity due to excessive fluid intake without sodium supplementation.
In high temperature (>38??) environment, excessive sweating leads to excessive loss of water and salts (including sodium, potassium and magnesium). Heat stroke cramps can occur after physical activity when fluid is lost through sweating and is simply hydrated. The result is a relative loss of sodium and occasionally potassium and magnesium.
Heat stroke cramps are common in manual workers in high temperatures (eg, steel workers, miners), climbers or skiers who wear excessive winter clothing, tennis players and other weekend athletes, and those who are not accustomed to heat and dryness A person who climates a lot of hidden sweating, the latter evaporating so quickly that excess sweating is barely noticeable. 3.1 Diagnosis of heat stroke and heat cramps
symptoms and signs
heat stroke cramps often come on suddenly, and the muscles of the limbs are first affected, manifested as severe pain and Spasms in the arms and legs prevent movement of the hands and feet. Often episodic, spastic muscles feel like indurations. If the spasm affects only the abdominal muscles, the pain can resemble an acute abdomen. Muscles become stiff, tense, and difficult to relax.
Vital signs are usually normal. The skin can be hot or dry and sticky, depending on the humidity.
3.2 Prevention and Treatment
Heat stroke cramps are usually preventable.
In most cases, just drinking liquids containing sodium chloride or eating foods containing sodium chloride can prevent and quickly relieve heat stroke cramps. Sodium chloride tablets are often used for prophylaxis, but may cause stomach irritation and, in overdose, edema, so their use is discouraged.
If the patient cannot eat or drink, intravenous drip of 0.9% sodium chloride solution is required. This is rarely the case.