• Why take capillary blood?
  • Rules
  • preparation General analysis
  • Tools
  • algorithm fence
  • Why does the ring finger?
  • What does the analysis?
  • Interpretation of results
  • What better to take blood for analysis - venous or capillary?
  • In conclusion

blood test - the most common laboratory research, which is prescribed for preventive examinations and virtually any address to the general practitioner.More often it requires general (clinical) analysis.In this case, give blood from a finger.Algorithm and delivery rules are familiar to all, without exception, from the very childhood.Everyone knows that the analysis should be to take the morning obligatory fasting.The procedure is very simple, and the results are usually ready the next day.

Why take capillary blood?

sampling blood from a finger is carried out in the following cases:

  • when overall analysis to determine the composition of the cell;
  • to determine the level of glucose (in this case, blood is taken from a vein and, at the sam
    e time the sugar level will be slightly different, which is normal);
  • rapid analysis to determine total cholesterol level (for a more detailed study is required venous blood).


  1. preparing to come to the lab in the morning (usually taking takes place from 7.30 to 10 hours) for donation of blood from a finger.
  2. analysis must pass an empty stomach, ie in the morning can not be there, you can only drink plain water.The last meal should take place the night before - not later than 8-12 hours before the procedure.
  3. day before you can eat, but it is recommended for a day or two prior to the analysis, not to get distorted results, abandon fatty foods and alcohol.
  4. eve to avoid physical and emotional stress.
  5. the morning before the procedure you need to refrain from smoking.

General analysis

It can be cut and expanded.A first embodiment includes such factors as the level of hemoglobin and blood cells (erythrocytes, platelets, leukocytes), and the ESR (erythrocyte sedimentation rate).

Blood sampling from the finger of the child
capillary blood in a child

In a detailed analysis, and added other factors, among which:

  • hematocrit;
  • width of the distribution of red cells;
  • average volume of red blood cell;
  • average content of hemoglobin in the red cell;
  • WBC and others.


Many people are worried about their own safety at the time of the analysis, so they can be a question of what is pierced and the blood was taken.Today, virtually all medical facilities have switched to the use of disposable instruments for lancing.This tool is called a lancet.It should be removed from the unopened package in front of the patient.I should say that this is enough to do the puncture hurt, so the procedure is not very popular with the children.

We advise you to read: Microscope and erythrocytes

normal blood counts Today, blood donation can be painless.Increasingly, a new device used when taking blood.This is an automatic lancet in a plastic case.The needle penetrates the skin quickly, so the pain is not felt.New lancets have many advantages:

  • sterile needle or blade is inside the body that ensures the safety of patients and medical staff;
  • reliability trigger eliminates the random output of the needle or blade;
  • possible re-use, thanks to the automatic return of the needle or blade;
  • needle form provides pain reduction effect;
  • puncture focused, its depth is controlled;
  • convenient form of housing.

algorithm fence

For laboratory must prepare:

  • sterile lancet;
  • wool;
  • alcohol;
  • tincture of iodine;
  • ether.
Disposable scarifier
disposable scarifier - a tool to puncture the finger

algorithm and taking the following equipment:

  1. patient sits in front of a laboratory assistant.Hand (usually the left) on the table.
  2. puncture site is disinfected with alcohol and degreased with ether.
  3. disposable lancet quickly make a puncture in the pad of the ring finger, plunging the tool to the full depth of the cutting part (about 2-3 mm).
  4. first drop of blood is removed with a dry cotton wool.
  5. used for the study, and the second following a drop of blood, which are gaining with a glass adapter, then placed in a test tube and sign.
  6. After blood is taken, the injection site is treated with alcohol or iodine and clamped with a cotton swab until it stops blood.

algorithm capillary blood sampling in a child is the same as that of an adult.

Why does the ring finger?

Perhaps someone is interested, from a fingertip blood is taken and why.The fence comes from the ring finger, although permitted in the middle or index.Puncture, as well as any violation of the integrity of the skin, can lead to infection.Nameless, index and middle fingers are insulated inner jacket, so in case of infection will initially be localized, which means that there is time to eliminate it.Big and little finger is directly connected to the brush cover, and if the infection spreads the infection to the entire brush.Selecting the ring finger because it carries the least exercise.

What does the analysis?

blood taken from the finger occurs as a preventive measure for the diagnosis and monitoring of treatment.This baseline survey and the basic, most essential characteristics of physicians that shows blood following:

  • hemoglobin;
  • level of red blood cells;
  • ESR;
  • level of white blood cells;
  • relative content of lymphocytes, monocytes, neutrophils, basophils, eosinophils.
Sampling blood from the finger by the automatic lancet
blood sampling using automatic lancet

With clinical analysis doctors can diagnose the following pathological conditions:

  • leukemias;
  • anemia;
  • bleeding disorders;
  • presence in the organism of an infectious or inflammatory process.

Interpretation of results

Explanation should be conducted only by the attending physician.Do not try to do it yourself on the basis of the tables, which contains the standard for each indicator.The physician evaluates the basic parameters not only individually, but also combined.
  1. hemoglobin .The rate for women - 120-140 g / liter for men - 130-160 g / liter.If the content is higher than normal, possibly dehydration, intestinal infections, congenital heart defect.Low levels indicate anemia.
  2. CPU (color index) .Normal - from 0.85 to 1.15%.Low values ​​indicate that anemia, elevated observed in folate deficiency, gastric cancer.
  3. Erythrocytes .The rate for men - 4-5 g / l for women - 3.7-4.7 g / L.Increasing evidence of renal disease, tumors, Cushing's syndrome.A slight excess of the norm may occur diarrhea, use of diuretics, burns.Low in talks about anemia, fluid overload, loss of blood.
  4. ESR .The rate of sedimentation of red cells - an indicator of the level of plasma proteins.Normally, women - 20 mm / hour in men - 15 mm / hour.The high level characteristic for inflammation, infections, autoimmune diseases, intoxications, endocrine, renal and hepatic pathologies, oncology.Causes of reduction - circulatory insufficiency, hyperbilirubinemia, erythremia.
  5. leukocytes .The rate of white cell - 4-9H10⁹ / liter.The reasons for the decline - the cancer with secondary tumors in the brain, diffuse connective tissue disease, typhoid fever, viral hepatitis, leukemia.Increased levels observed in bacterial and fungal infections, acute inflammation, septic infections, pneumonia, otitis, pancreatitis, bronchitis, meningitis, and so on.
  6. Platelets .Average content of blood platelets responsible for blood clotting, is 180-320H10⁹ / liter.High platelets indicate the development of rheumatoid arthritis, polycythemia, tuberculosis, myeloid leukemia.Reduced content accompanies thrombocytopenic purpura, aplastic and haemolytic anemia, hemolytic disease, lupus erythematosus.

What better to take blood for analysis - venous or capillary?

Externally, the blood from the veins and the finger a little different.Venous - darker blood capillary - bright blood.Patients often wonder why venous take if the finger to take the easier and more convenient.It is believed that a vein has the best laboratories in the world, and her research using new methods give more accurate results.

In conclusion

analysis of blood from a finger - quite informative method, even though it reflects only the general condition of the body.Abnormalities of certain parameters can not be regarded as confirmation of the presence of any disease.Changes in the blood can be suspected evolving pathology and pass a specific examination in the early stages, when symptoms are absent.The result can be distorted if you do not follow the rules and do not donate blood on an empty stomach and after a meal.In this case, appoint a reanalysis.