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Hematocrit
Last reviewed: 23.04.2024
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Hematocrit - the volume fraction of erythrocytes in whole blood (the ratio of the volume of erythrocytes and plasma). The amount of hematocrit depends on the number and volume of red blood cells. In modern hematology counters, the Ht-calculated (secondary) parameter is 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.
[Why is it important to determine hematocrit?
Red blood cells, the so-called red blood cells, contain the "respiratory" protein - hemoglobin. It is hemoglobin that plays an important role in the nutrition of tissues, as it is a “transport” for oxygen, and it also accelerates the output of carbon dioxide. Ideally, blood contains about sixty percent of a specific fluid - plasma, and the rest is proteins: white cells - leukocytes, flat blood plates - platelets and the erythrocytes proper. The hematocrit value is the norm of the ratio of red cells that predominate in the blood (up to 99%) to plasma, or a measure of deviation from the indicated norms. Thus, it can be said that hematocrit shows how well the red blood cells perform the respiratory function.
What determine the hematocrit value?
Many pathological conditions, diseases require a comprehensive examination, detailed laboratory tests, in which there are specific blood parameters. It helps to specify the diagnosis and begin an effective treatment. Any competent doctor will not be enough information that determines only the level of hemoglobin, 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 complements the assessment of the state of red blood cells. Together with the color marker, hemoglobin level, other information and hematocrit indices can complement and complete the diagnostic complex, which will help the doctor correctly interpret the clinical blood test. The abnormal hematocrit number shows changes in the erythrocyte system, which in turn signals diseases such as cardiovascular disease, anemia, oncopathology, and diseases of the gastrointestinal system.
How is the analysis done?
Hematocrit is not only a part of the general information of a clinical blood test, but also a glass capillary, a tube that looks like a small pipette. The device has a clear division - one hundred equal parts. For analysis, blood is taken from a vein with a needle, and blood is taken from babies less traumatic - using a lancet. Glass hematocrit, filled with material for research, is placed for an hour and a half in a special centrifuge. Under the action of centrifugal revolutions (up to 1.5 thousand per minute), the erythrocytes begin to settle to the bottom of the hematocrit capillary to a certain level, which is an informative indicator.
How is the hematocrit calculated, what is its rate?
The conditional normal level for women is from 35% to 42%, for representatives of the stronger sex this indicator is different - from 40% to 47% and higher, up to 52%. In children from one to five years, the hematocrit may be lower by 8–10% than in adults, but for newborn babies, on the contrary, the hematocrit increased by 20% is an acceptable norm.
What does hematocrit mean?
If to simplify completely, the hematocrit is an indicator of how high or low the level of blood density is. Of course, the hematocrit trait is interpreted according to a much more serious and specific pattern and is referred to as reduced, normal - within the boundaries or reduced.
When the percentage is higher than normal numbers, 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 diagnosis. Also, elevated hematocrit can signal erythremia, which is an extremely serious disease. In erythremia, erythrocytes begin to rapidly increase in number in the most important area of blood formation - the bone marrow. In addition, the hematocrit above the normal level may be with latent, latent or acute hypoxia (oxygen starvation), with polycystic kidney disease or tumors in them. Leukemia, peritonitis, thrombosis, diabetes, burns and even trivial sweating can result in an increase in hematocrit.
A decrease in hematocrit is characteristic of almost all types of anemia, and it also happens with poor kidney function. Hematocrit below the normal level is also the case with a large blood loss associated with injuries or surgery. It should be noted that in pregnant women during the last - third trimester, the hematocrit value is lowered for obvious reasons. More serious diseases, such as cancer, including blood diseases - myeloid leukemia, hemoblaztosis is also accompanied by low hematocrit.
You should not panic, independently studying the results of a clinical blood test, because such information is not a definitive diagnosis. If the hematocrit does not fit into the normal range, this does not mean that you have a deadly disease. The volume of red blood cells, as well as their relationship to plasma, is only part of the overall clinical picture, and not a direct indicator of the disease. In a word, hematocrit and its competent decoding is subject only to specialists, who will take into account all indicators of hematological research in the aggregate.