A hematocrit test is a blood test performed to evaluate the percentage of red blood cells in the blood. The function of red blood cells is to carry oxygen from the lungs to the rest of the body. Blood contains erythrocytes, white blood cells, platelets, and a liquid called plasma. If the Hct (Hematocrit) level is too high or too low, it indicates dehydration or some other health condition that might affect blood composition.

What is the hematocrit test used for?
The hematocrit test forms a part of CBC or complete blood count which is a common blood examination used to measure various components of the blood. It helps check one’s general health and is performed to diagnose the presence of any kind of blood disorders like anemia, polycythemia, etc. It is a simple and safe procedure.

How is the hematocrit test performed?
Blood sample
A healthcare provider will require a small blood sample to test one’s hematocrit. This blood can be drawn from a finger prick or the vein in the arm. If the test is a part of CTC, the healthcare provider will draw the blood from the vein in the arm.

Evaluation
The hematocrit is evaluated in the laboratory using a centrifuge, which spins at high speed, separating the contents of the blood into three parts – red blood cells, anticoagulant, and plasma. The RBCs are then compared to a guide that tells what proportion of the blood they make up.

What does the test result indicate?
Hct results come as numbers in the blood test report. These numerals represent the percentage of red blood cells in the blood. Suppose the test result is 42, it means 42% of one’s blood contains red blood cells, and the remaining is made up of white blood cells, blood plasma, and platelets. The normal ranges for hematocrit in different age groups are:

41- 50% – in adult males
36-44% – adult females
32-42% – children
45- 61% – in newborns

If the hematocrit level is lower than normal, it means:
A person has anemia because the body doesn’t have enough red blood cells.

It can also mean that one’s body is making too many white blood cells, which are indicative of certain kinds of cancers, including multiple myeloma, lymphoma, bone marrow disease, or cancers that can spread from other parts of the body to bone marrow.

If the hematocrit level is higher than normal, it means:
One’s plasma levels are low, which occurs due to dehydration and shock.

One’s body produces too many red blood cells. This may be due to heart failure, lung disease, polycythemia, or congenital heart disease.

When the results don’t fall in the normal range, it doesn’t always mean one has a health condition. Sometimes when one lives at high altitudes, it can cause high hematocrit levels because of a lack of oxygen. Pregnancy can lead to low RBC levels. It is important to understand that hematocrit levels can differ depending on a person’s age, sex, and altitude. Other factors that can affect the outcome of a hematocrit test are significant blood loss, severe dehydration, and blood transfusion in the recent past. It is best to ask the healthcare provider what levels are normal for an individual.

Symptoms of low hematocrit levels
If one has a low hematocrit level, one might show the following symptoms:

Weakness
Pale complexion
Low energy
Fatigue
Cold hands and feet
Irregular heartbeat
Breathing troubles

These symptoms sometimes indicate anemia which is further associated with other health conditions like nutrient deficiency, cancer, chronic bleeding, bone marrow disorder, sickle cell anemia, kidney failure, thalassemia, and autoimmune diseases.

Symptoms of high hematocrit levels
A person with a high hematocrit level might show the following symptoms:

Dizziness
Flushed skin
Headaches
Vision issues
Enlarged spleen

Conditions responsible for high hematocrit levels can be lung disease, heart disease, genetic disease, and kidney cancer.

When to consult a doctor?
If one experiences any unusual symptoms that may be indicative of any blood disorder, one should get in touch with the doctor. These can indicate either low or high hematocrit levels and can point toward an underlying health condition. So, it is better to get in touch with a doctor as soon as one notices the symptoms to avoid future complications. Also, if a person undergoes chemotherapy, the doctor performs regular hematocrit tests to monitor bone marrow health.

Conclusion
By now, we have understood that hematocrit depicts the proportion of red blood cells in the total blood volume. As discussed in this article, the doctor might ask a person to undergo a hematocrit test if one shows certain signs and symptoms. But many times, one’s lifestyle and demographic conditions also play a significant role in determining the RBC levels. So, it is important to always remember that one’s hematocrit test result is just one piece of information related to one’s health. One should get in touch with a healthcare provider to understand what the test results mean.