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12.5. First aid

First aid

Although when some type of accident or health problem occurs we have to go to the doctor, sometimes it is necessary to act urgently until a doctor can take care of the situation .

The first aid are made in exceptional situations, so you need to keep calm, to observe the situation and think about how they can help, but without doing anything we know to properly, because we can make things worse for the patient but our intention is to help you.

Possibly, if an accident has occurred, it is because that area is dangerous, so we will be very careful to prevent ourselves from crashing. Some tips to keep in mind if we are with an injured person are:

  • Make sure that there is no danger in the area to prevent another accident from occurring. For example, if you suspect that a person has received an electric shock, disconnect electrical appliances and never do so with wet hands.
  • Protect ourselves to avoid damage. If the accident occurs on the road, we must use the reflective vest to be seen and avoid being run over .
  • Protect the injured person from other possible damages.
  • Ask for help. In the countries of the European Union, including Spain, telephone 112 is the emergency telephone number (health, fire, security, etc.) that we have to call in case of any type of emergency. In other countries, like most Latin American countries, the comprehensive emergency telephone number is 911. We must speak slowly and clearly, indicating where exactly (town, street, floor, kilometer point, etc.) the person you need is located. help, and clarifying what happened (a fall, run over, fainting, etc.) and how the person is.

Emergency telephone number: What telephone number do I call in an emergency?.

  • After we have taken these steps and made sure that medical help is on the way, we will apply whatever emergency measures we can and know how to do until medical personnel arrive .

Activity: First aid 1.

Activity: First aid 2.

Activity: First aid 3.

Activity: First aid 4.

Some aspects to take into account when faced with an emergency situation are:

General rules before an accident

In the event of an accident, we must follow these basic rules:

  • We must not move the injured, as they may have trauma to the spine or head. If the person is inside a vehicle, we will not move them either, except in the event of a fire or when cardiopulmonary resuscitation is necessary.
  • We will check the status of your vital signs:
    • If he is conscious, we will talk, reassure and encourage the injured person.
    • To check if he has a pulse, we will put our index and middle fingers on his neck or on his wrist.
    • Check if he breathes.
      • If he breathes, we will leave him in the lateral safety position and wait for help to arrive. If the person has had a trauma, we will not move him.

Posición lateral de seguridad

Rama [CC BY-SA 3.0 fr, CC BY-SA 2.0 fr or CeCILL], via Wikimedia Commons

Video: Lateral safety position.

      • If he is not breathing, we will place the injured person in a supine position, we will try to clear the airways, and if necessary, we will do artificial respiration using the mouth-to-mouth method.
    • To check the pulse, we will put pressure on the neck with the index and middle fingers. If there is a pulse and it is necessary to continue with artificial respiration, we will continue. If there is no pulse, an external cardiac massage will also be necessary.
    • If there are hemorrhages with great losses of blood, we will try to stop them .
  • When the injured person is in the lateral safety position, we will try to keep him warm, but we will not give him food or drink.

If the accident is not serious enough to require medical assistance or we are waiting for help, we can carry out first aid:

Wound disinfection

The skin is a defensive barrier that protects us from the entry of pathogenic microorganisms, but when there is a wound, they take advantage of it to penetrate.

To avoid wound infection, you have to follow these steps:

  • Wash your hands well to decrease the chance of infection. In addition, you will use latex gloves to avoid total contact with the wound to prevent you from contracting an infection.
  • Clean the wound by washing it with soap and water or physiological saline, from the wound area outwards, ensuring that nothing strange remains in the wound, such as a grain of sand. If something had to be removed, we would use sterile tweezers.
  • Disinfect the wound. For example, with hydrogen peroxide or povidone iodine. We will not use alcohol.
  • If the wound has been produced with a sharp object, press the area so that the blood comes out and the wound is cleaned from the inside out.


When a blood vessel breaks, bleeding occurs. In case it is too big and that the injured person can bleed out, you should cover the wound with a clean cloth, not tissue paper or pieces of cotton because they fall apart. If the cloth you have put on gets soaked, do not remove it, put another on top and continue compressing the wound.

Do not make any tourniquet, as you can cause more damage than it has.

The blood that comes out of the veins comes out slowly. If the wound is on an arm or leg, if you get up, less blood will come out.

The blood that leaves the arteries leaves faster. If the wound is in an extremity, it presses strongly on the artery (femoral or brachial) that carries blood to the extremity near the groin or armpits.

Video: Bleeds and wounds.


The fracture is a fracture of a boneIf the bone goes through the skin, the fracture is open. And if it does not go through, in a closed fracture. The injured person will have to receive medical assistance, but until he arrives, you must:

  • Immobilize the affected limb by placing padded splints from the upper joint to the lower joint in the area where the fracture occurred.
  • If it's an open fracture, try to stop the bleedingDon't use disinfectants.
  • If the injured person has to be transported, avoid any sudden movement. But if you think the spine may be affected, you don't have to move the injured person.

Activity: Fractures.

Cardiac arrest

If the heart stops, it stops beating and the blood cannot carry the oxygen and nutrients that cells need to survive, and they die. To avoid this, we will perform a cardiac massage so that the heart beats again.

The first thing we will do in case of cardiorespiratory arrest, the most urgent thing, is to ask for help. We will check that the person is not breathing or has a pulse, and we will begin the cardiac massage.

In cardiac massage it consists of two movements:

  • 30 chest compressions. You must place the heel of one hand on the sternum of the person with cardiac arrest, the other hand on the first, and extend the arms to force the whole body. They should be done at a rate of about 100-120 compressions per minute.
  • 2 insufflations with an open airway and a stuffy nose.

CPR ends when normal breathing returns, the physician arrives, or the rescuer is exhausted.

Interactive activity: Heart massage.


When the airways are blocked, the air does not reach the lungs and suffocation occurs.

If a person cannot breathe because something (poorly chewed food, for example) clogs his throat, we will not try to put our fingers in the pharynx to extract it, since we can push it inwards. We can help to remove it with the Heimlich maneuver, pressing the upper part of the abdomen so that the air comes out very hard and expels the object from the airways.

If you can't breathe, but your throat isn't blocked, we'll do mouth-to-mouth artificial respiration.

Maniobra de Heimlich

By BruceBlaus (Own work) [CC BY-SA 4.0], via Wikimedia Commons

Video: What to do if an adult chokes?.

Video: What to do if a baby chokes?.

Real case: save life with the Heimlich maneuver

Choking is one of the main causes of death but, fortunately, it is avoidable if we perform the Heimlich maneuver.

Imagine that someone is eating on a restaurant terrace and a man chokes and cannot breathe. The rest of the diners either do not see it or do not know what to do in this case. People walking down the street keep walking. His companion hits him on the back without success.


If we are with a person who has fainted, we will check that they breathe and loosen the clothing from the neck and waist. We will lay the person on his back and leave him with his legs elevated and his head on the side. As always, we will call the doctor.


In the case of burns, the first thing we should do is eliminate, if necessary, the cause of the burn, extinguishing the flames or removing the substance that burns, for example. Then we will refresh the burned area with plenty of water, for about 30 minutes. We will wrap the burn with clean, damp cloths.

Just as important as knowing what to do is knowing what not to do with a burn injury. If flames have to be extinguished, we will not pour water on it, we will extinguish them by covering them or making the person roll. We just have to add water to the burn, no creams or ointments. Nor should we break the blisters that form because the liquid they contain protects from possible infection. If the burned person has clothes or something else stuck to the skin, we will not remove it.

Video: Burns.

Answer in your notebook

12.11.- Do you think it is necessary to know first aid? Why?


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