What is a hematocrit test. How is a hematocrit test performed. Why might a doctor order a hematocrit test. What do hematocrit test results indicate. How do hematocrit levels vary by age and gender. What conditions can affect hematocrit levels. How does altitude impact hematocrit measurements.

Understanding the Hematocrit Test: A Window into Blood Composition

The hematocrit test, often abbreviated as Hct, is a crucial diagnostic tool that measures the percentage of red blood cells in your total blood volume. This simple yet powerful test provides valuable insights into your overall health and can help identify various medical conditions.

Red blood cells play a vital role in your body’s functioning, acting as a transport system for oxygen and nutrients. Think of them as the subway system of your bloodstream, delivering essential cargo to every corner of your body. Maintaining the right proportion of red blood cells is critical for optimal health.

Why Is the Hematocrit Test Important?

The hematocrit test serves several important purposes:

• Diagnosing blood disorders
• Monitoring overall health
• Assessing the effectiveness of treatments
• Screening for nutritional deficiencies
• Evaluating hydration status

Healthcare providers often order this test as part of a routine check-up or when investigating specific symptoms. It’s particularly useful in diagnosing conditions such as anemia, leukemia, and polycythemia vera.

The Hematocrit Test Procedure: From Blood Draw to Results

The hematocrit test is a straightforward procedure that involves a simple blood draw. Here’s what you can expect:

1. A healthcare professional will clean the site, usually the inside of your elbow or back of your hand.
2. They’ll apply a tourniquet to make the vein more visible.
3. Using a sterile needle, they’ll draw a small amount of blood into one or more vials.
4. The site will be covered with a bandage to stop any bleeding.
5. Your blood sample will be sent to a laboratory for analysis.

The entire process typically takes just a few minutes. While you might feel a brief pinch or discomfort during the blood draw, most people find the procedure relatively painless.

Laboratory Analysis: The Science Behind the Results

Once your blood sample reaches the lab, it undergoes a fascinating process:

• The sample is placed in a centrifuge, a machine that spins at high speeds.
• This spinning causes the blood components to separate based on their density.
• Red blood cells, being the heaviest, settle at the bottom of the tube.
• The proportion of red blood cells is then measured and compared to the total blood volume.

This separation allows technicians to accurately determine your hematocrit percentage, providing valuable information about your blood composition.

Interpreting Hematocrit Test Results: What Do the Numbers Mean?

Understanding your hematocrit test results is crucial for assessing your health status. Normal ranges can vary slightly depending on the specific laboratory, but generally fall within these parameters:

• Adult men: 38.8% to 50%
• Adult women: 34.9% to 44.5%

For children, the normal range changes rapidly with age, so pediatric hematocrit levels are evaluated based on age-specific charts.

When Hematocrit Levels Are Out of Range

Abnormal hematocrit levels can indicate various health issues:

Low hematocrit levels may suggest:

• Anemia
• Nutritional deficiencies (iron, folate, vitamin B-12)
• Blood loss or internal bleeding
• Bone marrow disorders
• Chronic inflammatory diseases
• Kidney failure

High hematocrit levels might indicate:

• Dehydration
• Polycythemia vera
• Lung diseases
• Congenital heart disease
• Kidney tumors

It’s important to note that a single abnormal result doesn’t necessarily indicate a health problem. Your healthcare provider will consider your hematocrit results in conjunction with other tests and your overall health status before making a diagnosis.

Factors Influencing Hematocrit Levels: Beyond Health Conditions

Several factors can affect your hematocrit levels, even if you’re in good health:

Altitude and Hematocrit: A High-Level Connection

Living at high altitudes can naturally increase your hematocrit levels. The reduced oxygen levels in the air stimulate your body to produce more red blood cells, thereby raising your hematocrit percentage. If you reside in a mountainous region, your healthcare provider will take this into account when interpreting your results.

Pregnancy and Hematocrit: Adjusting for Two

Pregnancy can significantly impact hematocrit levels. The increased fluid volume in a pregnant woman’s body can lead to a temporary decrease in hematocrit percentage. This is a normal physiological change and doesn’t necessarily indicate a health problem. Healthcare providers use pregnancy-specific reference ranges when evaluating hematocrit levels in expectant mothers.

Recent Blood Transfusions: A Temporary Boost

If you’ve recently received a blood transfusion, your hematocrit levels may be temporarily elevated. It’s crucial to inform your healthcare provider about any recent transfusions before undergoing a hematocrit test to ensure accurate interpretation of the results.

The Hematocrit Test in Context: Part of a Bigger Picture

While the hematocrit test provides valuable information, it’s often performed as part of a more comprehensive blood analysis. The Complete Blood Count (CBC) is a common test that includes hematocrit along with other important measurements:

• Hemoglobin levels
• Red blood cell count
• White blood cell count
• Platelet count

By examining these factors together, healthcare providers can gain a more complete understanding of your blood health and overall well-being.

Beyond the Numbers: Symptoms and Clinical Presentation

While hematocrit levels are crucial, they’re just one piece of the diagnostic puzzle. Your healthcare provider will consider your test results alongside any symptoms you’re experiencing and your overall clinical presentation. This holistic approach ensures a more accurate diagnosis and appropriate treatment plan.

Preparing for Your Hematocrit Test: Ensuring Accurate Results

To ensure the most accurate hematocrit test results, consider the following tips:

• Inform your healthcare provider about any medications you’re taking, as some can affect hematocrit levels.
• Discuss any recent illnesses or medical procedures, including blood transfusions.
• If you’re pregnant or think you might be, let your healthcare provider know.
• Stay well-hydrated in the days leading up to the test, unless instructed otherwise.
• Follow any fasting instructions provided by your healthcare team.

By following these guidelines, you can help ensure that your hematocrit test results accurately reflect your current health status.

After the Hematocrit Test: Next Steps and Follow-Up

Once your hematocrit test is complete, you might wonder what comes next. Here’s what you can expect:

Interpreting Your Results

Your healthcare provider will review your hematocrit results along with any other tests performed. They’ll consider factors such as your age, gender, overall health, and any symptoms you’re experiencing. This comprehensive approach allows for a more accurate interpretation of your results.

Follow-Up Tests and Procedures

Depending on your hematocrit levels and other factors, your healthcare provider might recommend additional tests or procedures. These could include:

• More specific blood tests to investigate potential causes of abnormal hematocrit levels
• Imaging studies to examine organs that might be affecting your blood cell production
• Bone marrow biopsy in cases where a blood disorder is suspected

Remember, a single abnormal hematocrit result doesn’t necessarily indicate a serious health problem. Your healthcare provider will guide you through any necessary follow-up steps.

Living with Abnormal Hematocrit Levels: Management and Treatment

If your hematocrit test reveals levels outside the normal range, your healthcare provider will develop a management plan tailored to your specific situation. This plan may include:

For Low Hematocrit Levels

• Dietary changes to increase iron intake
• Supplements to address nutritional deficiencies
• Medications to stimulate red blood cell production
• Treatment for underlying conditions causing the low levels

For High Hematocrit Levels

• Phlebotomy (blood removal) to reduce red blood cell concentration
• Hydration therapy to dilute blood concentration
• Medications to suppress excess red blood cell production
• Management of underlying conditions contributing to high levels

Your healthcare provider will work with you to develop a treatment plan that addresses the root cause of your abnormal hematocrit levels while considering your overall health and well-being.

The Future of Hematocrit Testing: Advancements and Innovations

As medical technology continues to advance, the field of hematology is experiencing exciting developments that could impact how we perform and interpret hematocrit tests:

Point-of-Care Testing

Researchers are developing portable devices that can perform hematocrit tests quickly and accurately at the point of care. These innovations could make hematocrit testing more accessible, especially in remote or resource-limited settings.

Artificial Intelligence in Result Interpretation

Machine learning algorithms are being developed to assist in interpreting hematocrit results alongside other blood parameters. These AI-powered tools could help healthcare providers detect subtle patterns and make more accurate diagnoses.

Personalized Reference Ranges

As we gain a better understanding of how factors like genetics and lifestyle influence hematocrit levels, we may move towards more personalized reference ranges. This could lead to more accurate interpretations of individual test results.

While these advancements are promising, the fundamental importance of the hematocrit test in assessing blood health remains unchanged. As we look to the future, this simple yet powerful test will continue to play a crucial role in diagnosing and monitoring a wide range of health conditions.

Hematocrit Test: Uses, Procedure, and Results

What is hematocrit?

Hematocrit is the percentage of red blood cells in the total blood volume. Red blood cells are vital to your health. Imagine them as the subway system of your blood. They transport oxygen and nutrients to various locations in your body. For you to stay healthy, your body needs to have the correct proportion of red blood cells.

Your doctor may order a hematocrit, or Hct, test if they think you have too few or too many red blood cells.

A hematocrit test can help your doctor diagnose you with a particular condition, or it can help them determine how well your body is responding to a certain treatment. The test can be ordered for a variety of reasons, but it’s most often used to test for:

• anemia
• leukemia
• dehydration
• dietary deficiencies

If your doctor orders a complete blood count (CBC) test, the hematocrit test is included. Other tests in a CBC are a hemoglobin and reticulocyte count. Your doctor will look at your overall blood test results to gain an understanding of your red blood cell count.

Learn more: CBC (complete blood count) »

First you will receive a blood test. Afterward, it will be sent to a laboratory for evaluation.

Blood sample

A medical provider will need a small sample of blood to test your hematocrit. This blood can be drawn from a finger prick or taken from a vein in your arm.

If the hematocrit test is part of a CBC, a lab technician will draw blood from a vein, typically from the inside of your elbow or from the back of your hand. The technician will clean the surface of your skin with an antiseptic and place an elastic band, or tourniquet, around your upper arm to help the vein swell with blood.

They’ll then insert a needle in the vein and collect a blood sample in one or more vials. The technician will remove the elastic band and cover the area with a bandage to stop the bleeding. A blood test can be slightly uncomfortable. When the needle punctures your skin, you might feel a prick or pinching sensation. Some people also feel faint or lightheaded when they see blood. You may experience minor bruising, but this will clear up within a few days. The test will take only a few minutes, and you can resume everyday activities after it’s finished. Your sample will be sent to a lab for analysis.

Evaluation

In the laboratory, your hematocrit is evaluated using a centrifuge, which is a machine that spins at a high rate to cause the contents of your blood to separate. A lab specialist will add a special anticoagulant to keep your blood from clotting.

When the test tube is taken out of the centrifuge, it will have settled into three parts:

• red blood cells
• anticoagulant
• plasma, or the fluid in your blood

Each component will settle in a different part of the tube, with the red blood cells moving to the bottom of the tube. The red blood cells are then compared to a guide that tells what proportion of your blood they make up.

While the laboratory that tests the blood sample may have its own ranges, generally accepted ranges for hematocrit depend on your gender and age. Typical ranges are as follows:

• adult men: 38.8 to 50 percent
• adult women: 34.9 to 44.5 percent

Children ages 15 and under have a separate set of ranges, as their hematocrit levels change rapidly with age. The specific lab that analyzes the results will determine the normal hematocrit range for a child of a certain age.

If your hematocrit levels are too low or too high, it can indicate various problems.

Low hematocrit levels may be a sign of:

• bone marrow diseases
• chronic inflammatory disease
• deficiencies in nutrients such as iron, folate, or vitamin B-12
• internal bleeding
• hemolytic anemia
• kidney failure
• leukemia
• lymphoma
• sickle cell anemia

High hematocrit levels can indicate:

• congenital heart disease
• dehydration
• kidney tumor
• lung diseases
• polycythemia vera

Before getting the test, let your doctor know if you’ve recently had a blood transfusion or are pregnant. Pregnancy can decrease your blood urea nitrogen (BUN) levels due to increased fluid in your body. A recent blood transfusion can also affect your results. If you live at a high altitude, your hematocrit levels tend to be higher due to reduced amounts of oxygen in the air.

Your doctor will likely compare the results of your hematocrit test to the other parts of the CBC test and your overall symptoms before making a diagnosis.

A hematocrit test is not associated with any major side effects or risks. You may have some bleeding or throbbing at the site where the blood is drawn. Let your doctor know if you experience any swelling or bleeding that doesn’t stop within a few minutes of pressure being applied to the puncture site.

Hematocrit Testing: Purpose and Procedure

Written by Sarah Vallie

Medically Reviewed by Jabeen Begum, MD on November 09, 2022

• What Is the Hematocrit Test?
• Hematocrit Test Purpose
• Hematocrit Test Procedure
• Hematocrit Test Results

You need blood to carry oxygen through your body, remove carbon dioxide, and fight infection. To do this, your blood has different types of blood cells that do different jobs. If the levels of any of these blood cells are off, it can cause a host of problems for your body. A hematocrit test tells your doctor if your levels of red blood cells are off.

A hematocrit test (HCT test), sometimes called a packed cell volume test (PCV test), is a test that measures your hematocrit. Hematocrit is the level of red blood cells within your blood.

Your blood is made up of plasma and blood cells. Plasma is the liquid part of your blood and is made of protein, salts, and water. Over half your blood composition is plasma.

Suspended in that plasma are three types of blood cells:

• Platelets, also called thrombocytes, are small fragments that help your blood form clots so you stop bleeding.
• Red blood cells are the most abundant type of blood cell in your blood. They’re round with a slightly indented center and contain a protein called hemoglobin. Hemoglobin carries oxygen and removes carbon dioxide.
• White blood cells are part of your immune system. These cells are round with a distinct center. Their job is to fight off unknown invaders by producing antibodies.

Hematocrit tests measure how much of your blood is red blood cells and determine if that amount is normal.

Hematocrit tests are sometimes done as part of routine blood tests, but your provider may order them if they suspect you have a red blood cell disorder. Your red blood cell levels may also be checked before you have surgery. 

A red blood cell count outside the normal range can mean you have a disease or disorder. A low number of red blood cells is called anemia, while having too many red blood cells is called polycythemia.

Anemia. When you’re anemic, you don’t have enough red blood cells to carry oxygen to your tissues. 

There are several different types of anemia. The most common type is iron deficiency anemia. Your bone marrow produces blood cells, and it needs iron to make hemoglobin. If you’re lacking iron, your body can’t produce enough hemoglobin for your red blood cells. This type of anemia is common in pregnant women and people who have experienced blood loss.

Other types of anemia include:

• Anemias associated with bone marrow disease. Diseases, such as cancers like leukemia and myelofibrosis, can affect your bone marrow and may cause your bone marrow to underproduce blood cells. 
• Anemia of inflammation. Some types of inflammatory diseases, including cancer, Crohn’s disease, HIV/AIDS, kidney disease, and rheumatoid arthritis, can interfere with your body’s production of red blood cells.
• Aplastic anemia.Aplastic anemia is a rare but life-threatening type of anemia in which your body doesn’t produce enough red blood cells. It can be caused by autoimmune diseases, infections, medicines, and toxins.
• Hemolytic anemias. Hemolytic anemias happen when your red blood cells are destroyed faster than your body can replace them. You can be born with inherited hemolytic anemia, or you can acquire hemolytic anemia from some autoimmune disorders, cancers, infections, medicines, tumors, and viruses. Hemolytic anemia can also be acquired from an overactive spleen, a reaction to a blood transfusion, or a mechanical heart valve.
• Sickle cell anemia.Sickle cell anemia is a genetic condition in which the red blood cells form a crescent, or sickle, shape due to defective hemoglobin. These oddly shaped red blood cells die quickly, causing your body to always be lacking enough red blood cells.
• Vitamin deficiency anemia (pernicious anemia). Your body also needs vitamins, especially vitamin B12 and folate (B9), to produce healthy red blood cells. A lack of these vitamins, or inability to absorb B12, can cause your body to be unable to produce the red blood cells you need.

Symptoms of anemia may include:

• Chest pain
• Cold hands and feet
• Dizziness or lightheadedness
• Fatigue
• Headaches
• Irregular heartbeat
• Pale or yellowish skin
• Shortness of breath
• Weakness

Polycythaemia. Polycythaemia, also called erythrocytosis, is caused by too many red blood cells, which can cause your blood to become thicker and travel slower through your blood vessels and organs. There are two types of absolute polycythemia, which means polycythemia caused by the overproduction of red blood cells: polycythemia vera (PV) and secondary polycythemia. 

Polycythemia vera is a rare, slow-progressing bone marrow cancer. Most of the time it’s caused by a mutation on the JAK2 gene, a gene within the stem cells of bone marrow. This mutated gene tells your stem cells to reproduce constantly, The new cells also reproduce and, because they have this damaged gene, continue to reproduce until the abnormal cells overwhelm the normal cells. Most people are not born with this mutation; it happens sometime during your life, although doctors don’t know what causes it.

Secondary polycythemia happens when your body produces too much erythropoietin, a hormone made by the kidneys that tells your bone marrow to produce red blood cells. This can be caused by a problem with the kidneys, such as a tumor. It can also be caused by conditions that prevent your body from getting oxygen, like chronic obstructive pulmonary disease (COPD) and sleep apnea.

There are also conditions that cause your hematocrit level to rise because of too little plasma. These include apparent polycythemia and relative polycythemia. Apparent polycythemia is a lack of plasma that can be caused by drinking too much alcohol, smoking, and taking certain medications. Relative polycythemia happens when dehydration causes a lack of plasma.

Symptoms of polycythemia may include:

• Bleeding problems like excessive bruising or bloody noses
• Blurry vision
• Confusion
• Dizziness
• Gout
• Headaches
• High blood pressure
• Itchy skin
• Red skin
• Stomach discomfort
• Tiredness

Both anemia and polycythemia can become life-threatening.

The hematocrit test is done like any other blood test. The lab will likely draw blood from a vein in your arm or hand. To determine your hematocrit, the lab spins your blood sample at a high speed. This causes the plasma and blood cells to separate, and the heavier red blood cells sink to the bottom of the tube. The amount is measured to calculate what percentage of your blood is red blood cells.

Normal ranges of hematocrit can vary depending on your age, race, and sex. Generally, normal ranges are considered to be:

• For adult men, 38.3%-48.6%
• For adult women, 35.5%-44.9%
• For newborns, 45%-61%
• For infants, 32%-42%
• For kids, 30%-44%

Some factors can cause abnormal hematocrit results despite no underlying disease. These include: 

• Living at a high altitude
• Pregnancy
• Recent blood transfusion
• Severe dehydration
• Severe recent blood loss

If your results come back and your hematocrit is abnormal, your doctor may order further testing to find the cause.

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Blood test for hematocrit – prices from 30 rubles. in Moscow, 78 addresses

Determination of hematocrit is a clinical study that provides information on the ratio of the volume of erythrocytes and the liquid part of the blood. It reflects the level of oxygen exchange between the lungs and tissues of the body, the degree of hemoconcentration. The study of hematocrit is part of a complete blood count. The results are used to diagnose and monitor anemia and polycythemia, evaluate the effectiveness of therapeutic measures, in particular blood transfusions, determine the degree of dehydration, thickening or thinning of the blood, and determining the need for a blood transfusion. Blood sampling for analysis is carried out from a vein or capillaries. The hematocrit value is determined using standard centrifugation or in an automatic hematology analyzer. Reference values ​​for men – 39-51%, for women – 35-47%. The timing of the analysis does not exceed a day.

Determination of hematocrit is a clinical study that provides information on the ratio of the volume of erythrocytes and the liquid part of the blood. It reflects the level of oxygen exchange between the lungs and tissues of the body, the degree of hemoconcentration. The study of hematocrit is part of a complete blood count. The results are used to diagnose and monitor anemia and polycythemia, evaluate the effectiveness of therapeutic measures, in particular blood transfusions, determine the degree of dehydration, thickening or thinning of the blood, and determining the need for a blood transfusion. Blood sampling for analysis is carried out from a vein or capillaries. The hematocrit value is determined using standard centrifugation or in an automatic hematology analyzer. Reference values ​​for men – 39-51%, for women – 35-47%. The timing of the analysis does not exceed a day.

Hematocrit is a laboratory measure of the complete blood count, which reflects the ratio of the volume of red blood cells to the volume of plasma. The final value is expressed as a percentage and indicates the ability of the blood to carry oxygen. An increase in hematocrit is determined when the level of red blood cells in the blood increases or the amount of its liquid part decreases. Such conditions can be triggered by both diseases, such as polycythemia, and physiological conditions. The hematocrit decreases with a decrease in the level of erythrocytes and the intake of a large amount of fluid, which increases the plasma volume. Changes of this nature occur, for example, with blood loss followed by the introduction of saline.

Hematocrit depends not only on the concentration of red blood cells, but also on their size. So, with iron deficiency anemia, the size of red blood cells decreases, the hematocrit decreases. In clinical and laboratory practice, to determine this indicator, blood is taken from capillaries, less often from a vein. The result is expressed as a percentage or through a fractional number, reflecting the concentration of erythrocytes – l / l. The research procedure is performed in two ways – hematocrit can be determined using standard centrifugation or using a hematological analyzer. The test results are used in general therapeutic practice, in pediatrics, hematology, resuscitation, surgery and other areas of medicine.

Indications

The hematocrit test is part of the complete blood count. The study is performed during preventive examinations for the purpose of early detection of diseases and conditions accompanied by anemia, dehydration, polycythemia, polyglobulia, bleeding (hidden). Purposefully, the analysis is prescribed for suspected anemia, the symptoms of which are weakness, fatigue, headaches and dizziness, pallor and dry skin, brittle nails, and weight loss are objectively determined. The results of hematocrit allow to identify the pathology, establish the degree of its severity and track the effectiveness of the treatment, but do not indicate its cause.

Other indications for CBC with hematocrit include primary and secondary polycythemia. With these diseases, an increase in the number of red blood cells occurs. A hematocrit test is performed in primary polycythemia, when an increase in the concentration of red blood cells is associated with an increase in their production in the red bone marrow, and in secondary polycythemia associated with diseases of the cardiovascular and respiratory systems, kidney pathologies, and tumors. The determination of the hematocrit value is used in the diagnosis of conditions of dehydration, in bleeding, to resolve the issue of the need for blood transfusion and the introduction of saline, to monitor the effectiveness of these procedures.

A hematocrit test without examining the level of red blood cells and their morphology does not provide enough information to detect various hematological disorders. For the diagnosis of anemia and polycythemia, it is necessary to determine several indicators, including the number of erythrocytes, hemoglobin, ferritin, serum iron, transferrin, erythropoietin, OZhSS. In clinical practice, the study of hematocrit has become widespread due to the cost-effectiveness of the procedure, its reproducibility and availability. These three criteria are especially important for primary, including preventive examinations of large groups of patients.

Preparation for analysis and collection of material

When performing a general blood test with the determination of hematocrit, blood is taken in the morning, on an empty stomach. Special preparation for the sampling procedure is not required, but it is important to follow a few recommendations: the day before the study, you should refrain from drinking alcohol, at least 8-12 hours should pass after eating, you should stop smoking and physical activity in half an hour, avoid the effects of stressful factors. During the conversation with the doctor, it is worth informing him about the medications being taken so that their possible effect on the hematocrit value is taken into account when interpreting the results. There are no restrictions on the use of pure water.

Most often, blood for hematocrit testing is taken from the ring finger. The procedure is performed using a pen-scarifier or lancet. If a doctor recommends venous blood sampling, then a puncture of the cubital vein is performed. After taking, the biomaterial is mixed with an anticoagulant to prevent the clotting process. In laboratories, two methods are used to determine hematocrit – standard centrifugation and using a hematology analyzer. Their essence lies in the fact that in the process of centrifugation (rapid rotation), heavier and bulkier particles (erythrocytes) settle to the bottom. Then the height of the lower layer is determined and its percentage to the total height of the liquid is calculated. Preparation of the results of this study takes no more than 1 working day.

Normal values ​​

Hematocrit values ​​are expressed as percentages or fractions. The values ​​of the norm depend on age and gender. For men, they range from 39 to 51% or from 0.39 to 0.51. In women, the hematocrit is lower, since the blood is renewed more often, the norm values ​​​​are from 35 to 47% or from 0.35 to 0.47. In children, the indicator is determined by age:

• from birth to 7 days – 42-66%;
• from 7 days to 1 month – 36-63%;
• from 1 to 6 months – 30-48%;
• from 6 months to 2 years – 33-39%;
• from 2 to 6 years – 33-39%;
• from 6 to 12 years old – 35-45%;
• from 12 to 15 years old – 36-49%;
• from 15 to 18 years old – 37-49% for boys, 36-46% for girls.

A physiological change in hematocrit is observed during pregnancy, from the 20th week the values ​​gradually decrease, and before childbirth they increase to normal values. Some increase in the indicator is possible with oxygen starvation caused by frequent smoking, staying in high mountainous areas.

Increased value

An increase in hematocrit can be caused by an increase in the volume of red blood cells. Changes of this nature are observed in diseases accompanied by an increase in the number or size of red blood cells – with redistributive and true erythrocytosis, primary and secondary polycythemia, compensatory reactions of the cardiovascular system. Another reason for an increase in hematocrit is a decrease in the liquid part of the blood. Dehydration can be caused by burn disease, peritonitis, profuse diarrhea, vomiting, intestinal obstruction, hyperhidrosis.

Decreased value

One of the reasons for the decrease in hematocrit values ​​is erythropenia – a decrease in the number of red blood cells in the blood. The level of red blood cells falls when their production in the red bone marrow is disturbed in anemia, leukemia, long-term use of cytostatics and anticancer drugs. Sometimes the number of red blood cells in the blood is reduced due to their intense destruction. Such changes occur with hemolytic anemia, poisoning with hemolytic poisons, typhoid fever, malaria. After bleeding and restoration of circulating blood volume with saline, a temporary decrease in the level of red blood cells and hematocrit values ​​\u200b\u200bis also determined.

Another cause of low hematocrit values ​​is excessive fluid intake, which leads to blood thinning, a change in the percentage of red blood cells and plasma. The cause of overhydration can be water intoxication with circulatory failure, impaired renal function. Another reason for a decrease in hematocrit values ​​is hyperproteinemia, or an increase in the level of proteins in the blood. With such changes, the binding and retention of water in the body occurs. Hyperproteinemia develops in various conditions – with vomiting, diarrhea, acute infections, myeloma, Hodgkin’s lymphoma, paraproteinemic hemoblastoses.

Treatment of abnormalities

Hematocrit testing is performed routinely as part of a complete blood count. The test is an economical way to diagnose and monitor hematological disorders (anemia, polycythemia), dehydration conditions. If the final indicator deviates from the norm, then it is necessary to consult a general practitioner, pediatrician, hematologist to establish the cause of the violations and prescribe treatment. It is possible to prevent the influence of physiological factors on the hematocrit index if you follow the rules for preparing for the blood donation procedure – quit smoking, heavy physical exertion.

prices, take tests in Moscow near you in the DNAOM laboratory

Complete blood count 5 diff is a study of the qualitative and quantitative composition of blood elements.

The material for the study is venous blood.

CBC 5 diff includes:

• determination of the size, number, shape of erythrocytes and their hemoglobin content;
• determination of the ratio of plasma volume to blood cells;
• determination of the total number of leukocytes;
• calculation of the percentage of different leukocytes: neutrophils, lymphocytes, monocytes, eosinophils and basophils on an automatic analyzer;
• counting and evaluation of the average size of platelets.

The CBC is performed as the first screening test for complaints of “malaise”. The analysis gives an idea of ​​the possible areas where pathological changes occur and helps the clinician determine further examination tactics.

Indications:
• screening examinations within the framework of preventive, dispensary observation;
• basic examinations during hospitalization in therapeutic and surgical hospitals;
• diagnosis of anemia;
• diagnostics of inflammatory, infectious diseases;
• diagnostics of diseases of the blood system;
• monitoring of ongoing therapy and the course of various diseases.

Preparation
Special preparation is not required. It is recommended to take blood no earlier than 4 hours after the last meal (for children – before the next feeding). If possible, eliminate high emotional and physical stress the day before.

Interpretation of results
When interpreting the analysis, it should be taken into account that in 5% of healthy people, the blood test values ​​deviate from the accepted reference values. Blood counts depend on race and sex, age.

The most important indicators in the general blood test are:


1. Hb (hemoglobin) – hemoglobin;
2. Ht – hematocrit;
3. total number of erythrocytes in ;
4. MCV * — mean erythrocyte volume;
5. RDW * – distribution of erythrocytes by volume;
6. MCH * — average content of hemoglobin in 1 erythrocyte;
7. MCHC * – average concentration of hemoglobin in erythrocytes;
8. total platelet count;
9. total number of leukocytes ;
10. leukocyte formula.

*It should be taken into account that the value is not specific, the indicator should be used to diagnose anemia only in combination with other indicators of the general blood test and biochemical blood tests.

Determination of CBC parameters allows diagnosing conditions such as anemia/polycythemia, thrombocytopenia/thrombocytosis and leukopenia/leukocytosis, which can either be symptoms of a disease or act as independent pathologies.

Hemoglobin (Hb, hemoglobin)
A protein in erythrocytes that contains heme. The main function is the transport of oxygen.
Units of measurement: g/l.

Hemoglobin increase:


• dehydration: with severe diarrhea, vomiting, increased sweating, diabetes, burn disease, peritonitis;
• physiological erythrocytosis: in residents of highlands, pilots, athletes;
• symptomatic erythrocytosis: with insufficiency of the respiratory and cardiovascular systems, polycystic kidney disease; erythremia.

Decreased hemoglobin:


• anemia of various etiologies;
• overhydration.

Hematocrit (Ht, hematocrit)
An indicator of the proportion of cells in the majority of red blood cells to the liquid part of the blood.
Units: %

Increase in hematocrit:



• dehydration: with severe diarrhea, vomiting, increased sweating, diabetes, burn disease, peritonitis;
• physiological erythrocytosis: in residents of highlands, pilots, athletes;
• symptomatic erythrocytosis: with insufficiency of the respiratory and cardiovascular systems, polycystic kidney disease;
• erythremia.

Decreased hematocrit:


• anemia of various etiologies;
• overhydration.

Erythrocytes
Units: ppm/µl (10 ⁶ /µl).
Alternative units of measure: 10 ¹² cells/L.
Conversion factors: 10 ¹² cells/L = 10 ⁶ cells/µL = million/µL.

Increased concentration of erythrocytes:


• dehydration: with severe diarrhea, vomiting, increased sweating, diabetes, burn disease, peritonitis;
• physiological erythrocytosis: in residents of highlands, pilots, athletes;
• symptomatic erythrocytosis: with insufficiency of the respiratory and cardiovascular systems, polycystic kidney disease;
• erythremia.

Decrease in the concentration of erythrocytes:


• anemia of various etiologies;
• overhydration.

MCV
Estimated indicator, which is calculated based on the histogram of the distribution by size of erythrocytes. According to MCV, microcytic, normocytic and macrocytic anemias are distinguished. An increase in the indicator indicates the presence of large erythrocytes in the blood, a decrease indicates the presence of small ones.

Units: fl (femtoliter).

Increased MCV values:


• B ₁₂ – deficiency and folate deficiency anemia;
• aplastic anemia;
• liver diseases;
• hypothyroidism;
• autoimmune anemias;
• smoking and drinking.

Decreased MCV values:


• iron deficiency anemia;
• anemia of chronic disease;
• thalassemia;
• some types of hemoglobinopathies.

RDW (Red cell Distribution Width)
The calculated value, which is calculated on the basis of the histogram of the distribution of erythrocytes by volume. Reflects the heterogeneity of erythrocyte sizes. An increase in the indicator indicates that small and large red blood cells are present in the blood sample. Decreasing the value indicates the homogeneity of erythrocytes in the sample.

Units: %


Increasing RDW values:



• anemia with heterogeneity in erythrocyte size, including those associated with nutrition; myelodysplastic, megaloblastic and sideroblastic types; anemia accompanying myelophthisis; homozygous thalassemias and some homozygous hemoglobinopathies;
• a significant increase in the number of reticulocytes;
• condition after red cell transfusion;
• interference – cold agglutinins, leukemia, hyperglycemia.

MCH
A calculated indicator that characterizes the average mass of hemoglobin in an erythrocyte. An increase in the indicator is associated with a supersaturation of erythrocytes with hemoglobin, a decrease indicates a deficiency of hemoglobin.

Units: pg (picogram).

MCH increase:



• B ₁₂ – deficiency and folate deficiency anemia;
• aplastic anemia;
• liver diseases;
• hypothyroidism;
• autoimmune anemias;
• smoking and drinking.

Decreased MCH:


• iron deficiency anemia;
• anemia of chronic disease;
• some types of hemoglobinopathies.

MCHC
A calculated indicator that characterizes the average mass of hemoglobin contained in a unit volume of an erythrocyte.

Units: g/dl.
Alternative units of measurement: g/l.
Conversion factor: g/l x 0.1 ==> g/dl.

Increase in MCHC values:



• hereditary microspherocytic anemia.

Decreased MCHC values:


• iron deficiency anemia;
• anemia of chronic disease;
• some types of hemoglobinopathies.

It should be borne in mind that the MCHC value is not specific, the indicator should be used to diagnose anemia only in combination with other indicators of a complete blood count and a biochemical blood test.


Platelets
Units: thousand/µl (10 ³ cells/µl).
Alternative units of measurement: 10 ⁹ cells/l.
Conversion factors: 10 ⁹ cells/l = 10 ³ cells/µl = thousand/µl.

Increased platelet concentration:


• physical overexertion;
• inflammatory diseases, acute and chronic;
• hemolytic anemias;
• anemia due to acute or chronic blood loss;
• conditions after surgical interventions;
• condition after splenectomy;
• oncological diseases and hemoblastoses.

Decreased platelet concentration:


• pregnancy;
• B ₁₂ – deficiency and folic acid deficiency anemia;
• aplastic anemia;
• viral and bacterial infections;
• taking drugs that inhibit platelet production;
• congenital thrombocytopenia;
• splenomegaly;
• autoimmune diseases;
• conditions after undergoing massive blood transfusions.

Leukocytes
Cells with nuclei that perform protective functions. Formed in the red bone marrow and organs of the lymphatic system. There are 5 populations: neutrophils, lymphocytes, monocytes, eosinophils or basophils. Functions and lifetime depend on which population the leukocyte belongs to.

Units: thousand/µl (10 ³ cells/µl).
Alternative units of measure: 10 ⁹ cells/l.
Conversion factors: 10 ⁹ cells/l = 10 ³ cells/µl = thousand/µl.

Increase in the concentration of leukocytes:


• physiological leukocytosis: emotional and physical stress, exposure to sunlight, cold, eating, pregnancy, menstruation;
• inflammatory processes;
• viral and bacterial infections;
• conditions after surgery;
• intoxication;
• burns and injuries;
• infarcts of internal organs;
• malignant neoplasms;
• hemoblastosis.