With high temperatures, one of the most serious health risks is “heatstroke”, a phenomenon of overheating of the body which can be fatal.
Faced with heat, which affects its functioning as soon as the temperature exceeds 25 degrees Celsius, the human body triggers several cooling mechanisms to maintain itself at 37 degrees (sweating, increased blood flow in the most surface vessels). But sometimes that’s not enough, and the internal thermostat turns bright red. It’s heat stroke.
Not to be taken lightly!
Under the effect of this hyperthermia, the heart rate is disturbed and accelerates sharply, breathing and pulmonary ventilation too. Despite the rise in internal temperature, the body comes to conserve water as much as possible, sweating stops and urine darkens or even disappears for several hours.
In the multiple warning signs to watch out for: a fever above 40°C, an extremely rapid pulse, hot, red and dry skin, headaches, nausea and vomiting, impaired consciousness (drowsiness or, on the contrary, confusion, irritability, even aggressiveness).
Heat stroke is much more serious than other accidents also caused by heat but without fever (cramps due to heat) or with moderate fever (sunstroke, etc.). It can lead to blood clotting disorders causing brain damage, coma and even death without timely medical treatment.
Young children, under the age of five, and the elderly, with less efficient defense mechanisms, are most at risk. A poor state of health, diarrhea or pre-existing fever, taking certain medications, including tranquilizers and diuretics, or alcohol consumption – which dehydrates – increases the risk of heat stroke.
Call the emergency
But healthy adults are not immune to such thermal failure. Especially if they work or play sports outdoors in scorching temperatures. Intense or prolonged muscular effort under the dodger indeed exposes you to the risk of “exertional heatstroke” or “malignant hyperthermia due to effort”, by increasing the risk that the body temperature exceeds bearable limits.
Behavioral abnormalities are manifested: the person has a gait as if in a drunken state, appears increasingly irritable. Loss of consciousness or agitation with incoherent talk may appear afterwards.
Faced with heat stroke with the associated signs of severity, you must call the emergency services. “If a person has hot, dry skin and is delirious, convulsing, or is unconscious, call a doctor or ambulance immediately”, recommends WHO Europe. While waiting for help, cooling the body is essential.
It is thus recommended to place the person in a cool place, to remove superfluous clothing, to sprinkle him with cool water, to ventilate him, to make him drink in small quantities unless he shows disturbances of consciousness. Ice cubes, or at least a cold cloth, placed at the level of the groin, or even the neck, can also help to reduce the temperature.
To avoid heat stroke or dehydration, the recommendations of the health authorities remain the same from one heatwave episode to another: drink water regularly, avoid alcohol and caffeine, stay cool, avoid going out and physical exertion during the hottest hours.