Hematocrit
Understanding Hematocrit
What is Hematocrit?
A Hematocrit test (HCT), also known as the packed cell volume (PCV) test, measures the proportion of red blood cells (RBCs) in the blood. This test helps detect blood disorders and other medical conditions. It is often done as part of a complete blood count test that also measures other types of blood cells.
Human blood consists of red blood cells (RBCs), white blood cells (WBCs) or leukocytes, and platelets suspended in a fluid called plasma. RBCs transport oxygen throughout the body; thus, their optimal number is vital for health.
A Hematocrit test (HCT) measures the proportion of RBCs in your blood. The result is expressed as a percentage and represents the volume of red blood cells compared to the total blood volume. For example, if the hematocrit value is 50%, it means that 50% of your blood is made up of red blood cells. If the HCT level is too high, it may indicate dehydration, polycythemia (an excess of red blood cells), or other conditions that cause the blood to become more concentrated. On the other hand, a low hematocrit level could be a sign of anemia or other blood-related issues. Additionally, a Hematocrit test also helps monitor treatment efficacy for anemia or polycythemia. No special preparation is needed for this test; eat or drink as per your daily routine while taking this test.
Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The hematocrit test is a valuable tool for doctors and is often used in combination with other blood tests to get a complete picture of your overall health.
What is Hematocrit used for?
A Hematocrit test is done:
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As part of a complete blood count test to monitor your overall health.
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If you have symptoms suggestive of anemia, such as weakness, fatigue, pale skin, etc.
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If you have symptoms suggestive of polycythemia, such as headache, dizziness, weakness, bleeding gums, blurred vision, etc.
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If your healthcare provider suspects you have a red blood cell disorder.
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To monitor treatment efficacy for anemia or polycythemia.
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To detect dehydration.
What does Hematocrit measure?
A Hematocrit test measures the proportion of red blood cells (RBCs) in your blood as a percentage of the total blood volume. It is a crucial part of a complete blood count (CBC) and helps in assessing your blood health. RBCs are responsible for carrying oxygen from the lungs to different parts of the body. The hematocrit test provides valuable information about your blood's oxygen-carrying capacity.
Higher-than-normal amounts of RBCs produced by the bone marrow can cause the hematocrit to increase, leading to increased blood density and slow blood flow. On the other hand, lower-than-normal hematocrit can be caused by low production of RBCs, reduced lifespan of RBCs in circulation, or excessive bleeding, leading to a reduced amount of oxygen being transported by RBCs. Monitoring your hematocrit levels is essential for diagnosing and managing various blood-related disorders.
Interpreting Hematocrit results
Interpretations
Adult male |
40-50% |
Adult female |
36-46% |
Note: Normal range of Hematocrit depends on several factors apart from age, including gender, health condition, previous instance of diseases, etc. The range also varies slightly between different laboratories performing the test.
Lower-than-normal packed cell volume for RBCs indicates a low amount of RBCs in circulation and causes anemia.
Higher-than-normal packed cell volume for RBCs indicates a high amount of RBCs in circulation and causes polycythemia.
Hematocrit Test results are to be interpreted with the results of other tests including blood iron tests, RBC count, and hemoglobin tests while evaluating anemia.