Hematocrit

Hematocrit is the volume fraction of red blood cells in whole blood (the ratio of the volumes of red blood cells and plasma). The value of hematocrit depends on the number and volume of red blood cells. In modern hematological counters, Ht is a calculated (secondary) parameter derived from the number of red blood cells and their volume (Ht = RBCxMCV).

Hematocrit is a specific indicator of the percentage balance of plasma and red blood cells in human blood.

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Why is it important to determine hematocrit?

Erythrocytes, the so-called red blood cells, contain a "respiratory" protein - hemoglobin. It is hemoglobin that plays an important role in tissue nutrition, as it is a "transport" for oxygen, in addition, it accelerates the removal of carbon dioxide. Ideally, blood contains about sixty percent of a specific liquid - plasma, and the rest is made up of proteins: white cells - leukocytes, flat blood platelets - thrombocytes and erythrocytes themselves. The hematocrit number is the normal ratio of red cells, which predominate in the blood (up to 99%) to plasma, or an indicator of deviation from the specified norms. Thus, we can say that the hematocrit shows how well the erythrocytes of the blood perform the respiratory function.

Why is hematocrit determined?

Many pathological conditions and diseases require a comprehensive examination, detailed laboratory tests that include specific blood indicators. This helps to specify the diagnosis and begin effective treatment. Any competent doctor will clearly not have enough information that determines only the hemoglobin level; most likely, the doctor will prescribe a multifactorial study. Hematocrit is essentially nothing more than information and an indicator of the volume (and total) of red blood cells, and not their number, therefore, like a puzzle in the overall picture, it complements the assessment of the state of red blood cells. Together with a color marker, hemoglobin level, other information and indices, hematocrit can complement and complete the diagnostic complex that will help the doctor correctly interpret a clinical blood test. A hematocrit number that deviates from the norm shows changes in the erythrocyte system, which in turn signals diseases such as cardiovascular pathology, anemia, oncopathology, and diseases of the gastrointestinal system.

How is the analysis carried out?

Hematocrit is not only a part of the general information of a clinical blood test, but also a glass capillary, a tube similar to a small pipette. The device has clear divisions - one hundred equal parts. For analysis, blood is taken from a vein using a needle, in babies, blood is taken less traumatically - using a lancet. The glass hematocrit, filled with the material for the study, is placed in a special centrifuge for an hour and a half. Under the action of the centrifuge revolutions (up to 1.5 thousand per minute), erythrocytes begin to settle to the bottom of the hematocrit capillary to a certain level, which is an informative indicator.

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How is hematocrit calculated, what is its norm?

The conventional normal level for women is from 35% to 42%, for the stronger sex this indicator is different - from 40% to 47% and higher, up to 52%. In children from one to five years old, the hematocrit can be lower than in adults by 8-10%, but for newborn babies, on the contrary, a hematocrit number increased by 20% is an acceptable norm.

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What does the hematocrit number mean?

To put it simply, hematocrit is an indicator of how high or low the blood density level is. Of course, the hematocrit indicator is interpreted according to a much more serious and specific scheme and is designated as low, normal - within the limits or low.

When the percentage is higher than normal, there is reason to talk about the threat of erythrocytosis - a significant increase in the number of red particles in the blood, which in turn requires further diagnostics. Also, an increased hematocrit may signal erythremia, which is an extremely serious disease. With erythremia, red blood cells begin to rapidly increase in number in the most important area of hematopoiesis - the bone marrow. In addition, hematocrit above the normal level can also be with latent, hidden or acute hypoxia (oxygen starvation), with polycystic kidney disease or neoplasms in them. Leukemia, peritonitis, thrombosis, diabetes, burns and even banal increased sweating can result in an increase in the hematocrit indicator.

A decrease in hematocrit is typical for almost all types of anemia, and it can also occur with poor kidney function. Hematocrit below the normal level can also occur with significant blood loss associated with trauma or surgery. It should be noted that pregnant women also have a lower hematocrit during the last - third trimester for obvious reasons. More serious diseases, such as oncological diseases, including blood diseases - myeloleukemia, hemoblasticosis are also accompanied by a lower hematocrit.

You should not panic when independently studying the results of a clinical blood test, because such information is not a final diagnosis. If the hematocrit does not fit within the normal range, this does not mean that you have a life-threatening disease. The volume of red blood cells, as well as their ratio to plasma, is only part of the overall clinical picture, and not a direct indicator of the disease. In short, the hematocrit and its competent decoding are only subject to specialists who will take into account all the indicators of the hematological study as a whole.