What is hematocrit and why is it important. How is a hematocrit test performed. What are the normal ranges for hematocrit in adults and children. What can cause low hematocrit levels. How does hematocrit relate to overall health and wellness.

The Importance of Hematocrit in Blood Composition

Hematocrit is a crucial blood test that measures the percentage of red blood cells in a person’s blood volume. This measurement provides valuable insights into an individual’s overall health and can indicate various medical conditions. The hematocrit level depends on both the number and size of red blood cells present in the bloodstream.

Red blood cells play a vital role in the body’s functioning. They are responsible for:

• Transporting oxygen to body tissues
• Delivering nutrients throughout the body
• Removing waste products and carbon dioxide
• Distributing hormones from endocrine organs to target tissues
• Maintaining body temperature
• Regulating pH levels in body tissues
• Assisting in clot formation
• Preventing infections

Given these essential functions, it’s clear why monitoring hematocrit levels is crucial for assessing overall health and detecting potential issues.

The Hematocrit Test: Procedure and Preparation

How is a hematocrit test conducted? The process is relatively simple and involves drawing a blood sample from the patient. Typically, this test is performed as part of a complete blood count (CBC), which provides a comprehensive overview of blood cell components.

Is special preparation required for a hematocrit test? Fortunately, no specific preparation is necessary. Patients can eat and drink normally before the test, making it a convenient and accessible diagnostic tool.

What to Expect During the Test

During the blood draw, patients may experience varying levels of discomfort:

• Some individuals feel moderate pain
• Others may only sense a prick or stinging sensation
• Temporary throbbing or slight bruising may occur afterward

It’s important to note that any discomfort is typically short-lived and subsides quickly.

Reasons for Performing a Hematocrit Test

Why might a healthcare provider recommend a hematocrit test? There are several scenarios where this test becomes particularly valuable:

1. Suspected anemia or risk factors for anemia
2. Presence of blood in stools or vomit
3. Chronic medical conditions (e.g., kidney disease, certain types of arthritis)
4. During pregnancy
5. Unexplained fatigue, poor health, or weight loss
6. Persistent headaches
7. Heavy menstrual periods
8. Leukemia or other bone marrow problems
9. Monitoring during cancer treatment
10. Evaluating the effects of medications that may cause anemia
11. Assessing nutritional status
12. Investigating concentration problems

Additionally, hematocrit tests are often performed before and after major surgeries to ensure optimal patient health.

Understanding Normal Hematocrit Ranges

What are considered normal hematocrit levels? It’s important to note that normal ranges can vary slightly between laboratories. However, general guidelines for adults are:

• Males: 40.7% to 50.3%
• Females: 36.1% to 44.3%

For infants and newborns, the normal ranges differ:

• Newborns: 45% to 61%
• Infants: 32% to 42%

It’s crucial to discuss specific test results with a healthcare provider, as they can interpret the values in the context of individual health status and other factors.

Interpreting Low Hematocrit Results

When hematocrit levels fall below the normal range, it may indicate various underlying conditions. What are some potential causes of low hematocrit?

• Anemia
• Bleeding (acute or chronic)
• Bone marrow dysfunction
• Chronic illnesses
• Chronic kidney disease
• Hemolysis (destruction of red blood cells)
• Leukemia
• Malnutrition
• Nutritional deficiencies (iron, folate, vitamin B12, vitamin B6)
• Overhydration

Each of these conditions requires further investigation and appropriate medical management.

The Impact of High Hematocrit Levels

While low hematocrit levels are more commonly discussed, high hematocrit levels can also indicate health issues. What might cause elevated hematocrit?

• Dehydration
• Polycythemia vera (a bone marrow disorder)
• Chronic obstructive pulmonary disease (COPD)
• Congenital heart defects
• Living at high altitudes
• Smoking

High hematocrit levels can increase blood viscosity, potentially leading to circulation problems and increased risk of blood clots.

Hematocrit and Overall Health Assessment

How does hematocrit contribute to a comprehensive health evaluation? Hematocrit levels provide valuable insights into various aspects of health:

1. Oxygen-carrying capacity of blood
2. Hydration status
3. Nutritional health
4. Presence of chronic diseases
5. Bone marrow function
6. Response to medical treatments

By considering hematocrit levels alongside other blood tests and clinical symptoms, healthcare providers can develop a more accurate picture of a patient’s overall health status.

Managing Abnormal Hematocrit Levels

When hematocrit levels are found to be abnormal, what steps are typically taken? The approach depends on the underlying cause:

• For low hematocrit due to iron deficiency: Iron supplementation or dietary changes may be recommended
• In cases of chronic disease: Treating the underlying condition is often the primary focus
• For bleeding-related low hematocrit: Identifying and addressing the source of blood loss is crucial
• In cases of bone marrow dysfunction: Further testing and specialized treatments may be necessary
• For high hematocrit levels: Addressing dehydration, managing underlying conditions, or considering therapeutic phlebotomy in some cases

It’s essential to work closely with a healthcare provider to determine the most appropriate course of action based on individual circumstances.

Lifestyle Factors Affecting Hematocrit

Can lifestyle choices influence hematocrit levels? Indeed, several factors can impact hematocrit:

• Diet: Ensuring adequate intake of iron, vitamins, and other nutrients
• Hydration: Maintaining proper fluid balance
• Exercise: Regular physical activity can influence red blood cell production
• Altitude: Living at high altitudes can increase hematocrit levels
• Smoking: Tobacco use can elevate hematocrit

By addressing these factors, individuals may be able to positively influence their hematocrit levels and overall health.

Hematocrit in Special Populations

How do hematocrit levels and their interpretation differ in specific groups?

Pregnancy and Hematocrit

During pregnancy, hematocrit levels typically decrease due to the body’s increased blood volume. Regular monitoring is essential to ensure both maternal and fetal health.

Athletes and Hematocrit

Athletes, particularly those in endurance sports, may have naturally higher hematocrit levels due to increased red blood cell production. However, extremely high levels can raise concerns about blood doping.

Elderly Individuals

Older adults may experience a gradual decrease in hematocrit levels due to various factors, including reduced bone marrow function and chronic health conditions.

Advances in Hematocrit Testing and Research

What recent developments have occurred in hematocrit testing and related research? Several advancements are worth noting:

• Point-of-care testing: Rapid hematocrit measurement devices allow for quick results in various clinical settings
• Non-invasive monitoring: Research into methods for continuous, non-invasive hematocrit monitoring is ongoing
• Genetic factors: Studies exploring genetic influences on hematocrit levels may lead to more personalized interpretations and treatments
• Artificial intelligence: Machine learning algorithms are being developed to assist in interpreting hematocrit results in conjunction with other health data

These advancements promise to enhance the utility and accessibility of hematocrit testing in clinical practice.

The Future of Hematocrit in Personalized Medicine

How might hematocrit testing evolve in the context of personalized medicine? As our understanding of individual genetic and environmental factors grows, the interpretation and use of hematocrit results may become increasingly tailored to each patient. This could lead to:

• More precise reference ranges based on individual characteristics
• Improved prediction of disease risk and treatment outcomes
• Customized nutrition and lifestyle recommendations
• Integration with wearable health monitoring devices

The future of hematocrit testing holds exciting possibilities for enhancing personalized healthcare and disease prevention strategies.

Hematocrit and Global Health Challenges

How does hematocrit testing contribute to addressing global health issues? Hematocrit measurement plays a crucial role in several areas of global health:

• Anemia detection in developing countries
• Monitoring maternal health in resource-limited settings
• Assessing nutritional status in populations affected by food insecurity
• Evaluating the impact of infectious diseases on blood health
• Screening for chronic diseases in underserved communities

By providing a simple yet informative measure of blood health, hematocrit testing can help guide public health interventions and resource allocation in various global contexts.

Challenges in Global Hematocrit Testing

Despite its utility, hematocrit testing faces several challenges in global health settings:

• Limited access to laboratory facilities in remote areas
• Lack of trained personnel to perform and interpret tests
• Variability in testing methods and quality control across different regions
• Cultural barriers to blood drawing in some communities
• Financial constraints limiting widespread testing

Addressing these challenges requires innovative approaches, such as developing low-cost, portable testing devices and implementing telemedicine solutions for result interpretation.

Integrating Hematocrit with Other Health Metrics

How can hematocrit results be most effectively utilized in conjunction with other health data? To maximize the value of hematocrit testing, it’s important to consider it within a broader health context:

• Combining hematocrit with other CBC components for a comprehensive blood profile
• Correlating hematocrit levels with symptoms and clinical findings
• Integrating hematocrit data into electronic health records for longitudinal analysis
• Using hematocrit as part of risk assessment algorithms for various health conditions
• Considering hematocrit in the context of genetic and environmental factors

By taking a holistic approach to health assessment, healthcare providers can make more informed decisions and provide better patient care.

The Role of Patient Education

How can patient understanding of hematocrit contribute to better health outcomes? Educating patients about the significance of their hematocrit levels can have several benefits:

• Improved adherence to treatment plans
• Increased motivation for lifestyle changes
• Better understanding of the need for follow-up testing
• Enhanced ability to recognize and report relevant symptoms
• Greater engagement in shared decision-making with healthcare providers

By empowering patients with knowledge about their hematocrit and its implications, healthcare providers can foster more effective partnerships in managing health and preventing disease.

Ethical Considerations in Hematocrit Testing

What ethical issues should be considered in the context of hematocrit testing? As with any medical test, several ethical considerations come into play:

• Informed consent: Ensuring patients understand the purpose and implications of the test
• Privacy and confidentiality: Protecting sensitive health information
• Equitable access: Addressing disparities in testing availability
• Appropriate use: Avoiding unnecessary testing and associated costs
• Result communication: Delivering information in a sensitive and understandable manner
• Cultural sensitivity: Respecting diverse beliefs and practices related to blood and health

Adhering to ethical principles helps maintain trust in the healthcare system and ensures that hematocrit testing serves the best interests of patients and society.

Hematocrit Testing in Research

How is hematocrit utilized in medical research? Hematocrit measurements play a valuable role in various research contexts:

• Clinical trials: Monitoring patient safety and treatment effects
• Epidemiological studies: Investigating population-level trends in blood health
• Genetic research: Exploring hereditary influences on blood composition
• Environmental health studies: Assessing the impact of pollutants on blood parameters
• Sports science: Studying the effects of training and performance on blood characteristics

By contributing to diverse areas of research, hematocrit testing continues to expand our understanding of human health and disease.

Hematocrit Information | Mount Sinai

HCT

Hematocrit is a blood test that measures how much of a person’s blood is made up of red blood cells. This measurement depends on the number of and size of the red blood cells.

Blood transports oxygen and nutrients to body tissues and returns waste and carbon dioxide. Blood distributes nearly everything that is carried from one area in the body to another place within the body. For example, blood transports hormones from endocrine organs to their target organs and tissues. Blood helps maintain body temperature and normal pH levels in body tissues. The protective functions of blood include clot formation and the prevention of infection.

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

No special preparation is necessary for this test.

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

The hematocrit is almost always done as part of a complete blood count (CBC).

Your health care provider may recommend this test if you have signs of or are at risk for anemia. These include having:

• Before and after major surgery
• Blood in your stools, or vomit (if you throw up)
• Chronic medical problems, such as kidney disease or certain types of arthritis
• During pregnancy
• Fatigue, poor health, or unexplained weight loss
• Headaches
• Heavy menstrual periods
• Leukemia or other problems in the bone marrow
• Monitoring during treatment for cancer
• Monitoring medicines that may cause anemia or low blood counts
• Monitoring of anemia and its cause
• Poor nutrition
• Problems concentrating

Normal Results

Normal results vary, but in general they are:

• Male: 40. 7% to 50.3%
• Female: 36.1% to 44.3%

For babies, normal results are:

• Newborn: 45% to 61%
• Infant: 32% to 42%

The examples above are common measurements for results of these tests. Normal value ranges vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.

What Abnormal Results Mean

Low hematocrit may be due to:

• Anemia
• Bleeding

• Bone marrow being unable to produce new red blood cells. This may be due to leukemia, other cancers, drug toxicity, radiation therapy, infection, or bone marrow disorders 

• Chronic illness
• Chronic kidney disease
• Destruction of red blood cells (hemolysis)
• Leukemia
• Malnutrition
• Too little iron, folate, vitamin B12, and vitamin B6 in the diet
• Too much water in the body

High hematocrit may be due to:

• Bone marrow disease that causes abnormal increase in red blood cells (polycythemia vera)
• Congenital heart disease
• Exposure to high altitude
• Failure of the right side of the heart
• Low levels of oxygen in the blood
• Scarring or thickening of the lungs
• Too little water in the body (dehydration)

Risks

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight but may include:

• Excessive bleeding
• Fainting or feeling lightheaded
• Multiple punctures to locate veins
• Hematoma (blood buildup under the skin)
• Infection (a slight risk any time the skin is broken)

Chernecky CC, Berger BJ. H. Hematocrit blood. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:620-621.

Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. Blood disorders. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 124.

Means RT. Approach to the anemias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 149.

Vajpayee N, Graham SS, Bem S. Basic examination of blood and bone marrow. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 31.

Last reviewed on: 1/9/2022

Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What it is, levels, high and low range

Hematocrit is the percentage of red blood cells in a person’s blood. A typical hematocrit range in healthy adults is 37–52%. This varies depending on a person’s sex and age.

Authors of a 2017 study identified the above typical range.

Low red blood cell levels indicate conditions such as anemia. High red blood cell levels could signal polycythemia, increasing a person’s chance of developing a blood clot.

If a person feels tired, dizzy, or short of breath, a doctor may want to test their hematocrit levels to see if those levels fall into a normal range or not.

Read on to learn more about what this measure of red blood cell volume means, symptoms of abnormal levels, and what low and high levels might indicate.

Hematocrit measures the percentage of red blood cells in the body. For example: if a person has 50 milliliters (ml) of red blood cells in 100 ml of blood, their hematocrit level is 50%.

Red blood cells transport oxygen around the body and give blood its characteristic red color. In addition to oxygen, they also contain hemoglobin, a protein that binds to oxygen molecules. This allows red blood cells to pick up oxygen from the lungs and deliver it throughout the body.

An adequate amount of red blood cells is essential to keep the body’s processes running smoothly.

Many conditions can affect red blood cell production or its life cycle. This can make it difficult for a medical professional to diagnose these conditions. A doctor will use a hematocrit test to confirm whether a person’s red blood cell count is affecting a health condition.

Doctors usually test hematocrit levels as part of a complete blood count (CBC).

A CBC is composed of a range of tests and may include:

• red blood cell count
• reticulocyte count (young red blood cells)
• an analysis of hemoglobin levels
• an analysis of red blood cells, including size and shape
• white blood cell tests
• platelet tests

A doctor will also consider a person’s sex, race, and age. It is important to note that certain blood-related conditions, such as sickle-cell anemia, affect particular demographic groups at higher rates.

Learn more about sickle cell anemia in African Americans here.

A doctor may request frequent hematocrit tests to monitor the effect of chemotherapy on a person’s bone marrow.

Both high and low hematocrit levels can be detrimental to a person’s health and result from various conditions and lifestyle factors.

What are normal hematocrit levels?

Different institutions will define normal hematocrit levels differently. However, a 2017 cross-population study found the following ranges to be typical.

• Male: 42-52%
• Female: 37-47%
• Children: 30–44%, depending on their age and sex

Newborn babies have high hematocrit levels that gradually decrease as they get older.

If a person has recently received a blood transfusion, it may affect their results. Additionally, pregnant individuals may have lower levels than usual because the body increases its blood volume during pregnancy.

Other factors, such as smoking and chronic obstructive pulmonary disease (COPD), may push levels into a higher range.

Low levels

A hematocrit level below 35% in women and 41% in men is low. A level under this value can signify chronic anemia.

High levels

Hematocrit levels above the typical ranges can have adverse effects. It may indicate serious underlying health conditions.

Accuracy of results

Results from hematocrit tests are typically accurate and provide a clear reading of a person’s red blood cell levels.

However, the percentage of red blood cells in someone’s blood can change depending on various lifestyle factors and even environmental changes. According to research, red blood cell counts tend to increase at high altitudes.

Exercise, particularly strength training, may also affect hematocrit levels. A 2018 study found that females who participated in 16 weeks of strength exercise had lower levels at the end than when they started. However, the study had a small sample size of 26 middle-aged, sedentary Turkish women. This means that these findings aren’t necessarily representative of a wider population.

Dehydration can also raise hematocrit levels, so this test is useful if a doctor suspects severe dehydration is the cause of a person’s symptoms.

When a person has low hematocrit levels, they tend to present with the following symptoms:

• pale complexion
• weakness
• fatigue
• low energy
• trouble breathing
• irregular heartbeat
• cold hands or feet

These symptoms also indicate anemia, a condition where hemoglobin levels are lower than normal. Hemoglobin is a protein found in red blood cells that carries oxygen around the body.

Mild anemia is treatable, and it is particularly common in women. Severe anemia could signal a more serious underlying health condition that requires more extensive treatment.

Doctors associate anemia with several health conditions, including:

Nutrient deficiency

A person may lack B12, folate, or iron in their diet.

Learn more about how nutrient deficiency anemia is diagnosed and treated.

Chronic bleeding

This commonly occurs due to digestive tract ulcers, which are sores caused by the bacteria H.pylori or chronic use of anti-inflammatory medications such as ibuprofen, other nonsteroidal anti-inflammatory drugs (NSAIDs), and aspirin. Many women also experience excessive blood loss from heavy menstrual bleeding.

Bone marrow disorder

This includes aplastic anemia, which damages stem cells in bone marrow.

Cancer

These cancers spread to bone marrow, such as leukemia and lymphoma.

Learn more about bone marrow cancers here.

Kidney failure

Kidney disease can lower the production of red blood cells, reducing hematocrit levels.

Thalassemia

When a person has this condition, their body does not produce enough hemoglobin.

Learn more about thalassemia here.

Sickle cell anemia

This condition changes the shape of red blood cells. These cells die earlier than normal, and they also clump together, which impairs blood flow.

Learn more about sickle cell anemia here.

Autoimmune disease

Conditions like rheumatoid arthritis and lupus may reduce red blood cell count.

Learn more about autoimmune diseases here.

When a person has high hematocrit levels, they tend to present with these symptoms:

• flushed skin
• dizziness
• vision problems
• headaches
• enlarged spleen

These symptoms signal polycythemia, a condition where the body produces too many red blood cells. This means blood is thicker and clots more easily.

Doctors cannot cure polycythemia, so treatment focuses on symptom management. The main goal is to avoid stroke and deep vein thrombosis (DVT), which is a blood clot usually occurring in a deep vein in the leg.

In some cases, dehydration causes polycythemia. When a person does not drink enough, their plasma levels drop, increasing the proportion of red blood cells in their blood volume. A person can lower their red blood cell count by rehydrating.

Some conditions that can cause high hematocrit levels include:

Lung or pulmonary disease

When the lungs cannot absorb oxygen effectively, and oxygen levels drop, the body compensates by making more red blood cells. One common pulmonary disease causing this is COPD.

Learn more about COPD here.

Heart disease

If the structure of a person’s heart reduces its ability to pump blood around the body, it can no longer sustain vital organs with oxygen. To try and overcome the oxygen deficit, the body produces more red blood cells.

Learn more about heart disease here.

Kidney cancer

Sometimes kidney cancer cells create more erythropoietin. Erythropoietin is a hormone that tells the bone marrow to create more red blood cells.

Learn more about kidney cancer here.

Genetic disease

The JAK2 gene, which controls the number of blood cells made in the bone marrow, can affect certain conditions. When someone has a mutated JAK2 gene, the body could make a protein that signals the bone marrow to create more red blood cells than it needs.

Learn more about genetic disorders here.

A person should speak with a doctor if they are experiencing any of the symptoms listed above that could be a sign of high or low hematocrit levels, including fatigue, weakness, vision problems, and dizziness.

These symptoms can also indicate an underlying condition, so a person must contact a doctor promptly to prevent future complications.

If a person is receiving chemotherapy treatment, a doctor should perform regular hematocrit tests to monitor bone marrow health.

Hematocrit is the percentage of blood cells in a person’s blood volume. A doctor may test an individual’s hematocrit level due to certain symptoms.

A low hematocrit level means there are too few red blood cells in the body. In these cases, a person may experience symptoms that signal anemia. Common symptoms include fatigue, weakness, and low energy.

If a person has too many red blood cells, they have a high hematocrit level. A person may experience dizziness and headaches, which can be a sign of the condition polycythemia.

Demographic and lifestyle factors can influence a person’s hematocrit levels. For example, males tend to have higher levels than females. Pregnant individuals can experience a decrease in hematocrit levels, and strength training may also reduce levels.

There are also several health conditions that can cause hematocrit levels outside the normal range. Excessive bleeding, thalassemia, and kidney disease are causes of low levels. COPD and sickle cell anemia can cause high levels.

Read this article in Spanish.

Hematocrit

Hematocrit is the ratio of the volume of erythrocytes to the volume of the liquid part of the blood.

Determination of hematocrit is an integral part of the general blood test and is not performed separately.

Russian synonyms

Hematocrit value.

Synonyms English

Ht, Hct, Hematocrit, Crit, Haematocrit, PCV, Packed Cell Volume.

Units

% (percentage).

What biomaterial can be used for research?

Venous blood.

General information about the study

Hematocrit measures the volume of blood that red blood cells occupy in the bloodstream. This indicator is expressed as a percentage. For example, a hematocrit of 45% means that 100 milliliters of blood contains 45 milliliters of red blood cells.

An increase in hematocrit occurs if the number of red blood cells increases or the volume of the liquid part of the blood decreases, which happens when the body loses excess fluid (for example, with diarrhea). A decrease in this indicator is observed, on the contrary, with a decrease in the number of red blood cells (for example, due to their loss, destruction, or a decrease in their formation) or with overhydration – when a person receives too much fluid (for example, with excessive administration of intravenous solutions).

Hematocrit reflects not only the number of red blood cells, but also their size. If the size of red blood cells decreases (as in iron deficiency anemia), the hematocrit will also decrease.

What is research used for?

• In the diagnosis of anemia and polycythemia and to evaluate the effectiveness of their treatment.
• To determine the degree of dehydration.
• As one of the criteria for deciding on the need for a blood transfusion.
• To evaluate the effectiveness of blood transfusions.

When is the test ordered?

This test is part of a routine complete blood count, which is performed both routinely and in various diseases and pathological conditions, before surgical interventions.

In addition, it can be carried out repeatedly and at certain intervals:

• for dynamic monitoring and evaluation of the effectiveness of the treatment of anemia and polycythemia,
• after conditions causing dehydration,
• for recurrent bleeding for a comprehensive assessment of their severity.

What do the results mean?

Reference values ​​

Generally, the hematocrit corresponds to the number of red blood cells, but this is only true when the size of the red blood cells is normal. If the number of normal-sized red blood cells increases, the hematocrit also rises. In cases of large or small erythrocytes, this is not always the case. For example, with iron deficiency, red blood cells decrease and the hematocrit will be reduced, but the number of red blood cells per unit of blood may be normal and even slightly higher.

Hematocrit level above 55% requires clarification of the cause and further diagnostic search.

Causes of low hematocrit:

• iron-, B ₁₂ – or folic deficiency anemia,
• acute or chronic bleeding (hematocrit and hemoglobin levels will be elevated during or immediately after bleeding),
• disorders of hemoglobin synthesis (sickle cell anemia, thalassemia),
• cirrhosis of the liver,
• destruction of erythrocytes as a result of hemolysis – destruction of erythrocytes inside the body (it can occur for various reasons – due to a hereditary defect in erythrocytes, as a result of the appearance of antibodies to one’s own erythrocytes or toxic effects in malaria),
• oncological diseases of the bone marrow or metastases of other tumors in the bone marrow, leading to a decrease in the synthesis of red blood cells,
• excessive hydration of the body – the introduction of large volumes of intravenous fluids.

Causes of increased hematocrit:

• dehydration (dehydration) of any origin – due to diarrhea, profuse vomiting, diabetes, after burns,
• polycythemia vera due to excessive production of red blood cells in the bone marrow,
• chronic obstructive pulmonary disease,
• chronic heart failure.

What can influence the result of ?

1. The hematocrit level is normally reduced in pregnant women due to a physiological increase in the volume of the liquid part of the blood.
2. Persons ascending to high altitudes experience an increase in the number of red blood cells and, consequently, hematocrit, as their body adapts to the reduced oxygen concentration.
3. Hematocrit may be increased in smokers due to oxygen deprivation of tissues and increased production of red blood cells.
4. In newborns, the hematocrit level is increased, since they have quite a lot of large red blood cells in their blood.

Important Notes

• Red blood cell count, hemoglobin and hematocrit are strongly related to the degree of body hydration. If the volume of the liquid part of the blood decreases with excessive fluid loss, these indicators will increase. However, the absolute number of erythrocytes and hemoglobin does not change.

Also recommended

• Clinical blood test: complete analysis, leukocyte count, ESR (with blood smear microscopy if pathological changes are detected)
• Erythrocyte indices
• Reticulocytes
• Erythropoietin
• Erythrocytes
• Hemoglobin

Who orders the examination?

General practitioner, internist, hematologist, nephrologist, surgeon.

“Hematocrit below normal – what does this mean in an adult?” — Yandex Q

In this article we consider what to do if the hematocrit is below normal, what does this mean in an adult?

Determination of the hematocrit value is included in the extended complete blood count. The criterion allows you to evaluate the work of the hematopoietic system. The functioning of other organs directly depends on its full functional activity, since it is erythrocytes that deliver oxygen to organs and tissues.

A decrease in hematocrit may occur without the manifestation of pronounced clinical symptoms. A person can attribute increased fatigue to high workload and lack of time for rest. However, a decrease in hematocrit is one of the first symptoms of anemia that requires treatment. The article also addresses the issue of the danger of a long-term decrease in hematocrit.

Contents

• 1 What does hematocrit show?

• 2 Hematocrit is below normal – what does it mean?

• 3 Causes of Decreased Hematocrit in Adults

• 4 Is low hematocrit dangerous?

• 5 Methods for increasing hematocrit

What does hematocrit show?

The value reflects the volume of the liquid part of the blood, which in the bloodstream contains formed elements (erythrocytes, leukocytes, platelets). The hematocrit value is measured as a percentage. So, if the analysis indicates that the hematocrit is 40%, this means that 40% of red blood cells, platelets, etc. are present in 100 ml of blood.

Low blood hematocrit is observed in patients with a low number of red blood cells in the bloodstream. The indicator also takes into account the size of blood cells. Their decrease is naturally reflected in the results of the analysis.

Measurement of hematocrit is useful in the diagnosis of anemia and hyperproteinemia, as well as in assessing the effectiveness of the selected treatment methods. The test is performed on patients with dehydration to assess the severity of their condition. Included in the list of obligatory determinable indicators for people who are scheduled for blood transfusion, and for pregnant women.

Main article: What is hematocrit, why is it needed and what are its norms?

Hematocrit is below normal – what does it mean?

A low hematocrit in an adult indicates a decrease in the number of red blood cells in the blood. In this case, the doctor will prescribe additional laboratory tests and instrumental diagnostic methods. Among the laboratory parameters, it is important to determine: the level of iron and ferritin, as well as to evaluate the biochemical parameters of the blood. Of the instrumental methods, it is preferable to conduct an ultrasound examination of the digestive organs, liver and small pelvis. Based on the results of a comprehensive examination and the collected history of the patient, the doctor determines the cause of the low hematocrit.

It should be borne in mind that if a woman gave biomaterial for analysis during menstruation, then the hematocrit is below normal – this is a standard phenomenon. During this period, a woman loses a certain amount of blood, which means that the level of red blood cells is somewhat reduced.

It is important to follow the rules of patient preparation, as well as the collection and transport of biomaterial. During venipuncture, destruction of red blood cells in vitro (hemolysis) can occur. For example, due to strong or prolonged squeezing of the site of taking the biomaterial with a tourniquet or at the wrong temperature for storing the collected blood. The obtained indications cannot be considered reliable, and the patient will definitely need to re-take the biomaterial.

Causes of Decreased Hematocrit in Adults

Only the attending physician after a complete diagnosis can determine the exact cause in each specific case. Consider the main causes of low hematocrit in adults.

Anemia (anemia) describes a group of similar syndromes, united on the basis of a total decrease in the level of hemoglobin and the number of red blood cells. It should be noted that the isolated term “anemia”, without clarifying explanations, does not describe a specific disease. In this case, it is only a separate symptom of a disease.

The decrease in the number of erythrocytes is mainly accompanied by changes in their qualitative composition. Which leads to a deterioration in respiratory activity and the gradual development of oxygen starvation of the tissues of all organs. The main symptoms of anemia are:

• pale skin;
• increased weakness and fatigue;
• desire to eat chalk, earth, raw meat;
• hair loss, brittle nails, dry skin;
• decreased memory and performance;
• bluish or yellowish sclera;
• earthy skin tone;
• persistent drowsiness;
• frequent headaches and dizziness;
• shortness of breath even with little physical activity;
• tachycardia.

The main causes of anemia

There are many known mechanisms for the development of anemia. Let’s consider the main ones:

• Malfunctions in the process of synthesis of red blood cells and hemoglobin due to lack of iron and vitamins B 9 in the human bodyand 12, as well as for pathologies of the red bone marrow.
• Deficiency of red blood cells due to large blood loss, for example, in serious injuries or during surgery. A similar condition occurs in people with chronic bleeding (hemorrhoidal bleeding, intercycle blood loss in women, etc.). The main mechanism is a decrease in the concentration of iron, and not a decrease in the number of red blood cells.
• Mechanism of enhanced destruction of blood cells. The average lifespan of red blood cells is 4 months. With the manifestation of pathologies affecting the hematopoietic system, blood cells begin to degrade at an accelerated rate. The decay process is also influenced by external factors, for example, the use of vinegar in large quantities.

The prognosis of the outcome of iron deficiency anemia is extremely favorable. The condition is stopped by taking iron and vitamins. The outcome of other forms of anemia depends on their severity.

Fluid in the body

The hematocrit is also reduced with an increased fluid content in the body of an adult. This condition is not associated with excessive fluid intake, but with its retention in the body. Causes: kidney pathology, viral or bacterial infection. There is an increase in blood plasma volumes, while the number of red blood cells does not increase. This naturally leads to a decrease in the hematocrit value.

Hyperproteinemia and nutrition

Another reason is hyperproteinemia. Pathology is characterized by an excess content of proteins in the bloodstream. It occurs due to a violation of the normal functioning of the liver. Proteins begin to “attract” an excess amount of water, while the number of red blood cells does not increase. Thus, their percentage with blood plasma decreases.

In adult patients, the hematocrit is also reduced with a sharp change in diet, prolonged fasting and blood loss.

Pregnancy

During pregnancy, especially in the second trimester, a decrease in the considered value is considered normal. In women, the level of plasma volume increases, and red blood cells are not synthesized at an accelerated pace. Thus, the percentage of plasma-erythrocytes is shifted towards a decrease in the latter. The decrease in hematocrit value begins from the fourth week, reaching a peak by 31-35 weeks.

However, a long-term decrease in the index should not be ignored, it is necessary to conduct additional diagnostics in order to exclude the possible development of pathological conditions. Thus, a decrease in hematocrit up to 30% can cause the development of intrauterine fetal hypoxia, impaired fetoplacental circulation, fetal growth retardation, etc. An indicator of 15 to 25% indicates the need for immediate hospitalization of a pregnant woman, followed by continuous monitoring.

Other reasons

Also, low hematocrit in adults can be observed in:

• lead intoxication;
• splenomegaly;
• leukemias;
• conditions after chemotherapy;
• acute infectious processes;
• severe intoxications.

Is low hematocrit dangerous?

The main function of red blood cells is the sufficient supply of cells and tissues with molecular oxygen. With their decrease, there is an insufficient supply of oxygen to the organs. This has a particularly negative effect on the functional activity of the brain. A person has a decrease in concentration, memory and mental activity.

Adults with a low hematocrit are more susceptible to infectious diseases, are unable to function fully, get tired more quickly and lose concentration. In the future, a lack of red blood cells can lead to the development of pathologies of the cardiovascular system, liver and kidneys.

Methods for increasing hematocrit

Do not try to increase the level of red blood cells on your own. The necessary treatment will be selected by a specialist based on the results of laboratory and instrumental studies. In case of prolonged starvation or dehydration, it is necessary to restore the normal diet and the amount of fluid consumed per day.