Each year, more than one hundred people are struck by lightning in France and about fifteen of them die. If the lightning strike is not frequent, the danger is real and it is important to know how to guard against it, and what to act when confronted with it.

Lightning is a natural phenomenon that corresponds to a natural discharge of static electricity, which occurs from thunderstorms of clouds – called cumulonimbus. When a cold front meets a warm front, these cloud storms become loaded with water droplets and suspended ice crystals that rub together and collide. The droplets are negatively charged while the crystals are positively charged: it is this potential difference that generates lightning, which can take place either inside the clouds, or between two clouds, or between the cloud and the ground.

The victims of lightning are most often adolescents or young adult males.

According to a medical thesis which studied 104 victims of lightning in 1996 (1), the typical profile of the person struck by lightning is “a 32-year-old man, in good health, struck by lightning in the open air, in summer, in the mountains. afternoon, constantly presenting with CP [loss of consciousness], with anxiety and restlessness upon awakening, sometimes paraplegia, quite often superficial burns, sometimes temporary deafness ”.

Kerunopathology is the bio-medical specialty that studies lightning strikes. She classified four lightning strike mechanisms:

The direct shock  

Lightning falls on the highest point of the person, that is, on his head. The current passes through the body to the point of exit, namely at the level of the foot if it is in contact with the ground. Lightning strike by direct shock can cause cardiac damage if the current passes through the rib cage.

Side impact

It is the most common. It is a secondary lightning strike, following that of a nearby object. The most frequent example is that of the person who takes shelter from the storm under a tree, and the tree is struck by lightning. A side flash will then form between the tree and the person standing nearby. To put it simply, lightning “bounces” off the victim. This type of lightning strike is generally less serious.

Contact shock

It occurs when lightning strikes an object in direct contact with the victim. This is the case for example of a person who holds an umbrella, the current therefore passes from the object struck by lightning to the victim who holds it in the hand. The prognosis for this type of lightning strike is often severe.

Step voltage 

It is a lightning strike via the ground, when lightning strikes near a person. The current then passes from one leg of the victim to the other, sparing the heart. This type of lightning strike, on the other hand, kills many more in quadrupedal animals, insofar as the current passes from the front legs to the rear legs, thus passing through the heart.

In general, most outdoor activities should be interrupted in the event of a thunderstorm, especially those practiced in or near water, such as swimming, fishing and all water sports. . Sports practiced with a conductive metal object such as golf or mountaineering (ice ax) are also prohibited.

Here are other precautions to take: 

• In the event of a walk in nature, it is advisable to stay away from any metallic structure such as a pylon or a fence;
• Do not take shelter under a tree, especially if it is isolated. The risk of being struck by lightning under a single tree is multiplied by 50;
• Do not take shelter under an umbrella;
• Do not circulate in a close group, and keep at least 3 meters away from other people to avoid side impact;
• If you are walking alone in nature and without a safe shelter under which to take shelter: adopt the safety position by lying in a ball, ideally on an oilskin or an insulating fabric;
• At home, avoid using landline lines during a thunderstorm. If the home is not equipped with a surge arrester, it is recommended not to touch metal parts of the house – such as taps – or household appliances.

If possible, take refuge under a safe shelter, which can be for example: a church, a chapel, a stone building or a car with doors and windows closed, provided it is not convertible with a soft roof .

Lightning strike is an absolute emergency, so the first thing to do is tocall 15.

While waiting for help

While waiting for help, if the person struck down is unconscious, they are probably in respiratory and / or cardiac arrest. Mouth to mouth should then be practiced.

In the absence of a pulse

In the absence of a pulse, an emergency cardiac massage must be done on the victim.

If the victim is conscious

If the person is conscious and does not have serious signs, they should nevertheless be taken to the hospital to have their general condition checked. Sometimes complications arise within 48 hours of the lightning strike.

The victim must then be followed up on a regular basis, in particular on the cardiovascular, neurological, auditory and ocular level.