Hematocrit

What is hematocrit?

Hematocrit is a measure that indicates what proportion of your total blood volume is made up by red blood cells. This proportion is expressed as a percentage. The term EVF, an abbreviation for erythrocyte volume fraction, is used as a synonym in medical laboratories.

Red blood cells, also called erythrocytes, perform an essential task: they transport oxygen from the lungs to all tissues and organs in the body. The hematocrit therefore indicates how well this transport proceeds. A healthy percentage points to a good balance between blood volume and the number of functioning red blood cells.

The value is always viewed in conjunction with other blood values, such as hemoglobin and the number of red blood cells. Together, they provide a complete picture of the quality and quantity of your red blood cells.

Why is hematocrit measured?

Hematocrit is measured as part of a complete blood count, a standard examination that gives doctors insight into overall health. It is a useful measurement for symptoms such as fatigue, shortness of breath, or dizziness, but also for monitoring known conditions such as anemia or kidney problems.

For people who exercise frequently or are physically active, the hematocrit value is particularly relevant. Athletes have a higher oxygen requirement. The measurement helps to clarify whether the body can adequately meet this demand. Moreover, hematocrit is used in sports medicine as one of the parameters to monitor load capacity and recovery.

Blood volume also changes significantly during pregnancy, which affects the hematocrit value. Regular monitoring helps to make timely adjustments if the values ​​fall outside the normal range.

What can abnormal values ​​mean?

Hematocrit that is too high

An elevated hematocrit means that red blood cells occupy a larger proportion of the blood volume than usual. A common cause is dehydration: with a fluid deficit, the water content of the blood decreases, while the number of red blood cells remains the same. As a result, the blood becomes relatively thicker and the percentage increases.

In addition to dehydration, conditions of the heart, lungs, or bone marrow can also cause a hematocrit that is too high. In certain bone marrow disorders, such as polycythemia vera, too many red blood cells are produced. In these cases, an elevated value can lead to reduced blood flow, resulting in symptoms such as shortness of breath, chest pain, or dizziness.

Hematocrit that is too low

A reduced hematocrit indicates that there are insufficient red blood cells present in the blood. The most well-known cause of this is anemia. With anemia, there are too few healthy red blood cells to supply the tissues with sufficient oxygen.

Anemia can have various causes, including a deficiency of iron, vitamin B12, or folic acid, but chronic diseases or blood loss can also play a role. Symptoms that may occur with a low hematocrit value include:

• Fatigue and a feeling of weakness

• Shortness of breath during exertion

• Dizziness or lightheadedness

• Palpitations

• Headache

• Restless legs

The severity and type of symptoms depend on the underlying cause and how strongly the value deviates. It is always advisable to discuss an abnormal result with a doctor so that the cause can be determined.

When should you have your hematocrit measured?

Measuring hematocrit is useful for persistent symptoms such as fatigue, paleness, or shortness of breath without a clear explanation. Even if you know you have an increased risk of anemia, for example due to a one-sided diet, a chronic illness, or recent surgery, a measurement can provide valuable information.

Furthermore, it is advisable to have your hematocrit tested as part of a periodic health check. A single abnormal value does not tell the whole story. The value should always be assessed together with other blood values ​​and in the context of your personal situation and symptoms.

At Zample, you can have your hematocrit measured as part of a complete blood count. The result gives you concrete information about how your body transports oxygen and forms a good basis for a discussion with your doctor if anything stands out.