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the key element in the determination of the hematocrit

A Microcentrifuge is a specialized centrifugal machine used in the clinical laboratory. It rotates a smaller sample to rotationally separate its components or phases (usually a solid and a liquid), depending on its density. This is for use for capillary tubes. In this method the blood is centrifuged in capillary tubes for hematocrit until the maximum density of cell compaction is reached, therefore, the microcentrifuge is a key equipment for the determination and manual verification of the hematocrit value.

Some types of microcentrífuges

Microcentrifuges are divided into several types, but the most used are:

-High speed microcentrifuge.

-Refrigerated high-speed microcentrifuge.

What information provides the determination of the hematocrit?

The hematocrit value indicates the volumetric percentage of erythrocytes in blood. The reference method for determining the hematocrit is centrifugation. By centrifugation, the solid components of the blood are separated from the liquids and packed hermetically. Then, the glass capillary tubes “are centrifuged until the product reaches a minimum relative centrifugal acceleration that acts on the erythrocytes (RCF> 5.000)”

The hematocrit is the percentage of the total volume of blood composed of red blood cells. The average values vary between 40.3 and 50.7% in men, and between 36.1 and 44.3% in women, due to the greater musculature and therefore greater need for oxygen of the first.

These figures can change according to various physiological factors, such as the age and physical condition of the subject. It is an integral part of the blood count, along with the measurement of hemoglobin, and the count of leukocytes and platelets. A low level of erythrocytes causes anemia; there are numerous factors that can contribute to develop anemia, such as low iron intake; or patients with chronic kidney disease, who do not generate enough erythropoietin to stimulate the production of red blood cells in the bone marrow. The increase in the hematocrit indicates a polycythemia (increase in the number of red blood cells).

Determination of the hematocrit with standard capillary tubes

The hematocrit can be determined by centrifugation of heparinized blood in a capillary tube (also known as a microhematocrit tube) at 10,000 rpm for five minutes. This separates the blood into layers. The volume of red blood cell concentrate, divided by the total volume of the blood sample gives the hematocrit. Because a tube is used, this can be calculated by measuring the lengths of the layers.

What are the steps to follow for determination?

To determine the hematocrit, the following steps must be followed:

-Filling: When filling the capillary tubes, it must be taken into account that the end opposite the filling hole remains dry. To determine the hematocrit, the capillary tubes will be filled up to approx. 75%. of your capacity.

-Closing: The dry end of the capillary tubes must be closed with putty. To do this, the capillary tubes should be punctured in the putty vertically until the edge of the capillary tubes touches the bottom of the putty plate. Tilt the capillary tubes slightly to the side and remove them from the putty.

-Centrifugation: Place them with the closed end facing outward into the hematocrit rotor and replace the rotor cover.

-Then proceed to reading: through a scale for the reading of hematocrits.

In Kalstein we offer microcentrifuges for hematocrit of the highest technology. That’s why we invite you to take a look at our microcentrifuges available HERE