Hematocrit Range

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Usually, the hematocrit value for men is approximately 45%, whereas for women, it is around 40%.

Hematocrit gives a general idea about red blood cell (RBC) count in the bloodstream. Hematocrit range conveys the volume of red blood cells present in blood. It tells us how much space red blood cells are occupying in a given volume of blood. Hematocrit value measures the amount of space occupied by RBCs when packed together, in a sample of blood.

The measured hematocrit values are always interpreted in percentage. For instance, in case the hematocrit reading of an adult male is 35%, it indicates that a sample of 100 milliliters of blood contains 35 milliliters of red blood cells. As we all know, the blood is mainly made up of plasma (fluid part of blood), red blood cells and white blood cells (WBCs). RBCs and WBCs circulate in the body through the blood stream and remain suspended in blood.

Of the total volume of blood, plasma constitutes 55% and is made up of dissolved proteins and glucose. So, when the percentage of RBCs increases or decreases, as compared to plasma volume, it is a cause for concern. This can be found out using hematocrit test in which a sample of of blood is collected to check for the proportion of red blood cells.

The hematocrit level for both sexes will not remain the same. The reading will show different results depending upon the gender. It is observed that hematocrit level is higher in men than in women. Another factor that influences hematocrit reading is the age. To simply put, hematocrit reading will be different for both children and adults. With age, hematocrit value fluctuates but never goes beyond 70%.

According to National Institute of Health, normal hematocrit values are in the range:

• For women: 36.1% to 44.3%
• For men: 40.7% to 50.3%

In women, it is normally in between 37% and 48%. On the contrary in men, it is usually in the range of 41-50%.

• For a newborn baby: 42% to 65%
• For a two-month old baby: 28% to 55%
• For a three-month old baby: 30% to 36%
• For a child in the age group of 6-12 years: 35% to 46%
• For a healthy boy in the age group of 12-18 years: 36% to 49%
• For a healthy girl in the age group of 12-18 years: 36% to 46%

Disturbances in normal hematocrit levels, that remain for a considerable amount of time, can be a symptom of wide range of health problems. Blood disorders such as polycythemia vera, heart or kidney problems and intake of anabolic steroids are some of the factors that may cause a rise in hematocrit value. Other causes are discussed below:

Depleting fluid levels is nothing but dehydration. Dehydration decreases plasma level in the blood. Plasma is the watery portion of the blood on which red and white blood cells are seen. When the percentage of plasma reduces, the body shows elevated hematocrit levels. In this case, to restore normal hematocrit range, one simply has to drink adequate water. Replenishing water stores in our body is the key to decrease hematocrit levels.

This is a bone marrow disease that is typically marked by elevated red blood cell count. Bone marrow, the delicate tissues inside the bones are responsible for producing red blood cells. In polycythemia rubra vera, the bone marrow does not function properly, which causes an increase in RBC production, subsequently causing hematocrit value to rise above 55%.

This condition leads to excretion of watery stools, in turn causing excessive fluid loss. This may reduce the volume of plasma water and increase volume of RBC, eventually leading to increase in hematocrit level.

Elevated hematocrit levels can also be due to erythrocytosis, a condition similar to polycythemia rubra vera that causes causes increase in the number of red blood cells (RBCs). This has been primarily attributed to abnormality in the bone marrow stem cells but can occur due to secondry factors such as chronic lung disease.

When the lungs are unable to deliver sufficient oxygen to the body, the kidneys respond by increasing the production of red blood cells. The increase in the number of oxygen carriers helps to meet the needs of the body. Abnormally high hematocrit levels has often been linked to chronic lung problems such as emphysema, a type of chronic obstrictive pulmonary disease (COPD), that causes progressive destruction of air scas in the lungs.

In this condition, the adrenal glands located near the kidneys fail to produce hormones (aldosterone and cortisol) in sufficient amounts. These hormones play a key role in regulating blood pressure. It is observed that blood tests of people affected with Addison's disease reveal abnormally high hematocrit levels.

This is an inborn defect in which the structure of the heart is not properly developed. This hinders the blood circulation through the heart. Low oxygen levels are common in CHD patients. A a result, the body producs more number of RBCs (oxygen carriers) to improve oxygen levels. This rise in RBC production can also cause hematocrit range to climb above normal level.

Severe burns can significantly decrease the presence of plasma water and raise RBC count in the blood. This ultimately manifest in the form of high hematocrit levels.

Elevated hematocrit levels are also observed in people who have the habit of smoking. Smoking constricts the blood vessels and reduces the oxygen flow to different parts of the body. In an attempt to increase oxygen supply, the body increases the production of red blood cells (oxygen carriers), which eventually elevates hematocrit levels.

Staying at high altitudes such as a hill station can also raise hematocrit count. It is a known fact that at higher altitudes, the oxygen availability reduces and is always less than normal. In such circumstances the body also increases RBC production to fulfill its demand of oxygen. All this contributes in increasing the volume of red blood cells.

Epogen or EPO is primarily used for the treatment of anemia (low RBC count). However, athletes have been using or rather abusing it to enhance their performance. Athletes who have been taking high doses of EPO are likely to show a significant rise in RBC count, which may lead to elevated hematocrit levels.

Results indicating low hematocrit levels, cannot be ignored and is a cause for worry. Fatigue, weakness and dizziness are some of the most common symptoms of low hematocrit levels. Low hemoglobin levels and pregnancy is commonly associated with a decreased hematocrit range. The causes are elaborated below:

This condition causes a significant reduction in the number of red blood cells. When the RBC count is too less, there is a sharp drop in hematocrit levels. In fact, a person with low hematocrit levels is considered to be anemic. Anemia is usually diagnosed in people suffering from iron deficiency.

This condition brings premature death of red blood cells. In other words, hemolysis decreases the life span of red blood cells, leading to significant reduction in RBC count, thereby causing lowered hematocrit levels in the body.

Vitamin B12, iron and folate play a key role in the production RBC cells. Deficiency in any of these nutrients can cause a drop in RBC count, which can lead to low hematocrit levels.

Internal bleeding due to presence of ulcers in the digestive tract can also lower hematocrit range. Heavy blood loss from external wounds or during menstruation can also be responsible for decreasing hematocrit levels.

Less than normal hematocrit values may also signal renal failure, in which the kidneys fail to perform their necessary function. Renal failure can be either acute (rapid decrease in kidney function) or may occur gradually over a period of time. In either case, the amount of space occupied by red blood cells in the blood is bound to reduce substantially.

Chemotherapy drugs that are commonly used to treat cancer can also have a negative impact on normal RBC count. These drugs that are formulated to kill cancer cells may also destroy healthy red blood cells. This in turn may reduce volume of red blood cells (RBCs) in the blood.

In pregnant women, there is 45-50% rise in plasma volume. Although RBC volume also increases, it is insignificant in comparison to plasma volume. As a result, during pregnancy, the hematocrit range decreases.

Certain medications can also influence hematocrit range. People who are taking antibiotics such as chloramphenicol and penicillin are at increased risk of developing anemia, which may lower hematocrit range.

People suffering from rheumatoid arthritis and leukemia have also been diagnosed with hematocrit range that is far less than normal. On the whole, abnormally low or high hematocrit range is a cause for concern and requires evaluating the underlying cause and taking the necessary treatment.

Disclaimer: The information provided in this story is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.