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Laboratory: information for families

What you have to know

The fear of children and adolescents to the punctures is sometimes more intense than the fear they feel for other procedures that are carried out in the hospital and that can even be more invasive and annoying. Facing it can generate emotions in patients who are often difficult to manage also for companions. That is why we give you some tips that may be useful to prepare for the blood test before coming.

What is an extraction and what is it for?

An extraction or blood test is a simple procedure that consists of collecting a small amount of blood by means of a puncture with a fine needle. This procedure is performed by specialized professionals (in this case in pediatric patient) and, once they have collected the blood, they send it to the laboratory to analyze it. The first option is always to make the puncture in the arm. However, sometimes in babies it can be done in other body parts.

What is the use of this type of test?

The blood test is used to know the patient's health. In the blood there is information that the medical team can use to establish the diagnosis, the treatment, or to see the therapy that the patient is following is working.

The procedure, step by step
  1. An elastic band is placed on the arm, above the elbow. This tape tightens a bit and serves to locate the veins and choose one.
  2. Once the vein has been chosen, the area is cleaned with cotton and alcohol. The boy or girl will feel fresh on the arm because of the effect of this previous cleaning.
  3. The vein is punctured and only the amount of blood needed is removed. The child will feel like a pinch or a mosquito bite. Sometimes it's necessary to do more than one puncture.
  4. The elastic band is removed from the arm and then the needle.
  5. The area where the puncture was done is covered with a plaster or cotton. It will be necessary to press the area for a few minutes.
  6. The blood is placed in a tube and taken to the laboratory for analysis.
General tips to prepare the extraction

The imminence of the medical test can generate anxiety. When children become nervous, blood vessels contract and blood may be harder to draw. For this reason it is important that they come as calmly as possible. To prepare children from home, before arriving at the Hospital, the following general considerations can be taken into account:

  • It is necessary that they know where they are going. It is advisable to tell the truth to the children and explain to them that they will go to the hospital to have an analysis. If they show resistance it is important to ask why: we could find out if there is anything that scares them.
  • What to explain? It is recommended to explain, in a clear and simple way, what a blood test is. This explanation must be adapted to the age, characteristics and needs of each child to know the procedure. It must be considered that not all children reassure them that they know in detail the proof to which they will be subjected so that, if they do not want to know the details, they must be respected.
  • Parents can be with the patient during the extraction in most cases. It is important to explain that they can be accompanied whenever it's possible and in case that they want it.
  • It is recommended that they enter calmly. To help them arrive in a relaxed attitude it is possible to distract them with whatever they want before the test.
Considerations for different types of patients
  • Infants: at this stage children are sensitive to sensory stimulation (sound, touch, etc). It is recommended for the parents or caregivers to be near him or her the time of extraction, as it can reassure them. If there is any object or toy that relaxes the child, bring it to distract him during the puncture.
  • Patients up to 12 years old. If it is the first time and you want to know the procedure, you have to explain to them in a simple way, clear and adapted to their age, what the puncture is. If it is not the first time, listen to what they need and what could make the procedure easier.
  • Teenagers. It may be the case that it is the first time that they have a blood draw or that they already know the procedure. It is important to listen to them and explain what they need to be calmer.
  • Patients with cognitive impairment. They are sensitive to sensory and unknown stimulation. It helps to be accompanied by people who already know and to be distracted by something that relaxes them, such as music or caresses. The caregivers know what can calm them down during the procedure: communicate it to the staff and bring the objects or toys that can facilitate the test.
  • If you think that the removal can be a very difficult time for the child or adolescent, contact the Child Life team, which helps patients who have great difficulty in coping with medical procedures.
  • In some specific cases, analgesics (such as sucrose in babies or a cryo-anesthetic cold spray) can be used to reduce anxiety and pain.
The fast

In most cases it is necessary to do the test without having eaten food for a few hours in order to correctly read the results. As for the fast, the age ranges determine the number of hours that must pass without eating food. The general guidelines are the following:

  • 8 hours, usual fast. Generally, children over 3 years old are extractions under fasting conditions of 8 hours. This means that, to make the test, it is necessary that 8 hours have passed since the last time you ate. Children can drink water to alleviate thirst until the moment of extraction.
  • Between 1 and 3 years: 3 hours fast. They can drink some liquid (milk or natural fruit juice) when between the intake and the test a minimum of 3 hours elapses.
  • Fasting in infants: 3 hours. In the case of infants, the ideal time to do the extraction is just before they eat, when the babies have been about 3 hours without taking any food.
  • It is not necessary to fast: there are some tests that do not require hours without eating food such as genetic tests, some allergy studies or preoperative controls, among others.
  • Drug analysis. If it is an analysis of the levels of a certain drug, it must be taken into account that the patient does not take it before the extraction, since this analysis is done to know the predose values.

IMPORTANT! If the doctor who requested the test makes any special recommendation regarding the extraction, always follow his advice.

During the blood test
  • It is important that children are still during the test. It is useful to know what things relax or distract the patient to make extraction easier.
  • Immobilization. It consists of keeping the child fastened to avoid sudden movements during the test. While it is not necessary to immobilize all patients, in case it is necessary to do so, it is important to understand that it is a practice that is done to guarantee the success of the test and the safety of the child.
  • It hurts? Children often ask this question. You have to be honest, tell them they will notice the puncture but that the pain is not intense and lasts a few seconds.
  • It is important to recognize the courage of children. If we do, sure that this assessment by parents and professionals will be well received. In the hospital's extraction booths they have bravery certificates and coloring drawings. Ask the staff if you think it's a good idea.