Finger blood sampling is a fairly common procedure. The need for such an analysis from time to time is faced by each person, regardless of gender and age. Therefore, many are interested in: how to donate blood from a finger correctly? What is determined during the study of its samples? What rules should be followed to get the most accurate results?
Why do we need analysis?
Many patients in polyclinics and hospitals are first sent to take a blood test from a finger. In addition, a similar study is being carried out in preventive measures. To date, the study of samples of the so-called capillary blood is the most accessible and at the same time informative method. After all, its results give the doctor the opportunity to determine the condition of the whole organism.
Thanks to such laboratory studies, it is possible to establish a more or less accurate blood formula, as well as determine its group and the presence of a Rh factor in it. In addition, a general analysis allows you to know the level of hemoglobin and indicators of the erythrocyte sedimentation rate.
Definition of the blood formula: why is it needed?
Laboratory research allows you to establish the approximate number of shaped blood cells, which makes it possible to determine the general condition of the body. After all, it is no secret to anyone that almost any disease entails a change in the blood formula. What exactly do laboratory assistants and doctors pay attention to?
- The number of leukocytes is counted, as well as a differential analysis (the number of basophils, eosinophils, neutrophils, monocytes and lymphocytes is determined). The number of white blood cells increases in the presence of infection and inflammation, and a change in the level of each of the varieties of these cells indicates a particular problem.
- In addition, hemoglobin level and red blood cell count are measured. For example, a decrease in the number of red blood cells may indicate anemia.
- Platelet counts can help identify some bone marrow diseases and may also indicate a bleeding disorder.
What is ESR?
During a general blood test, the erythrocyte sedimentation rate is determined . The results of this analysis are not specific - they indicate the presence of certain violations, but do not provide information on the causes of their occurrence. The essence of the study is simple - the sedimentation rate of red blood cells in plasma depends on their ability to aggregate (bonding). The normal ESR is 2–15 mm per hour for women and 1–10 mm per hour for men. A change in the indicator can be an indirect sign of inflammation and some other pathological processes.
How to donate blood from a finger? Preparation rules
It should immediately be noted that there are many factors that can affect the composition of the blood and some of its properties. That is why many people are interested in the question of how to donate blood from a finger correctly. In fact, the rules here are very simple:
- They take a blood test from a finger in the morning, always on an empty stomach. Laboratory studies will be most accurate only if the samples are taken 8-12 hours after the last meal. That is why in most clinics, blood sampling is carried out precisely from 7.00 to 11.00.
- In the morning it is allowed to drink only a small amount of plain water (not carbonated, not sweet).
- An exception can only be cases where a patient is suspected of some serious, serious illness, in particular myocardial infarction, appendicitis, acute pancreatitis - in such situations you can not wait until the morning.
- In no case should you donate blood if you consumed alcohol the night before. The presence of alcohol in the body can distort the test results, so it is best to transfer the analysis to another day.
- Experts recommend avoiding intense physical activity before taking samples, as well as visiting saunas, baths, and taking a cold shower. Strong effects on the body of external factors can affect the blood formula.
- Immediately before the analysis, you can not rub your fingertips, as this can affect the number of leukocytes in the formula.
This is how the rules on how to donate blood from a finger look like. Do not neglect the recommendations, because incorrect test results can affect the final diagnosis.
Finger blood sampling: algorithm
The previous paragraph described the preparation for the study. But how is blood sampling from the finger carried out? The algorithm looks something like this:
- Capillary blood is taken from the fourth (ring) finger of the left hand.
- To begin with, the laboratory assistant must wipe the skin with an antiseptic (most often an alcohol solution is used for this purpose).
- To puncture the skin, a special scarifier needle is used. A puncture is made on the side of the first phalanx of the finger. The needle is inserted to a depth of 2.5–3 mm.
- It should be noted that after the puncture, the blood should flow freely. Some lab technicians squeeze tissues tightly to improve blood flow. The problem is that at this pressure tissue fluid is mixed with the blood, which naturally affects the result of the study.
- The first drop of blood that comes out must be wiped with a sterile cotton swab - it is not informative.
- First, a small amount of blood is collected to determine the hemoglobin level and measure ESR. The second portion of blood is used to determine the number of shaped elements. Then, using glasses, smears are made that allow you to quickly examine cells under a microscope.
- It should be recalled that during the procedure the laboratory technician must use clean, sterile instruments and disposable gloves.
Where can such an analysis be done?
As already mentioned, a finger blood test is prescribed for almost every patient who comes to the doctor with complaints of health. This is the simplest, most accessible and informative study, which provides the specialist with information about the general condition of the patient's body.
Therefore, blood sampling, as well as its laboratory research, is carried out in almost every hospital and clinic. There are also private diagnostic clinics offering the same service. If you have questions about where to donate blood from a finger, then you just need to ask your doctor.