When hematocrit, blood count, or HCT, is seen in the blood test, one may wonder. So, what does low and high HCT mean? Yeditepe University Kozyatağı Hospital Internal Medicine Specialist Dr. Mehmet Akif Öztürk explained the unknowns about HCT (hematocrit).

Hematocrit values appear on a complete blood count test, also called a hemogram. These values, which are of great importance for health, may decrease or increase for any reason. So, what is HCT (hematocrit)? What should the HCT value ranges? What are the symptoms of low HCT (hematocrit)? What causes low and high HCT? Yeditepe University Kozyatağı Hospital Internal Medicine Specialist Dr. Mehmet Akif Öztürk talked about what is curious about HCT (hematocrit)...

What is Hematocrit?

Hematocrit refers to the ratio of erythrocytes, which are found in our veins and whose main function is to carry oxygen and carbon dioxide, to the total amount of red blood cells.

What should be the HCT (hematocrit) value ranges?

Hematocrit value ranges differ according to female and male gender. For males, especially in the adult age population, this value is roughly between 38-48, while normal values in females can be expressed as the range of 35-45.

How is HCT (Hematocrit) measured?

Today, hematocrit can be measured with fully automated blood count measuring devices. In the evaluation of complete blood count, not only hematocrit but also many parameters such as leukocyte (white blood cells) number and subtypes, platelet (clotting cells) number and average volumes are examined.

What are the situations where the hematocrit value changes?

To mention the reasons that increase and decrease hematocrit; The reasons that increase are living in high altitude areas, smoking, low water consumption, sleep apnea, heart diseases, carbon monoxide poisoning, COPD disease and, rarely, bone marrow diseases.

Reducing causes include anemia, pregnancy, excessive water consumption, chronic kidney disease, thyroid diseases and, rarely, bone marrow diseases.

What causes low HCT (hematocrit)?

Anemia is the most common cause. This situation is associated with the inadequate production of blood cells due to iron deficiency, which is common especially in women who continue their menstrual cycle (menstrual cycle). There is an imbalance between construction and destruction. The main component of red blood cells is the iron element. If the intake of iron-containing food is insufficient or if the patient has a problem with the absorption of iron from the intestine, a sufficient amount of red blood cells will not be made, and hematocrit will be low.

What are the symptoms of low HCT (hematocrit)?

• Fatigue, 
• Palpitation,
• Chest pain,
• Hypotension,
• Intolerance to exercise, that is, getting tired quickly at the beginning of the exercise,
• Shortness of breath,
• Pale skin color,
• Coldness in the extremities of the body, that is, in the hands and feet,
• Headache and dizziness can be counted.

What causes high HCT (hematocrit)?

Hematocrit elevation may be due to excessive production of red blood cells. This can occur physiologically, that is, as an adaptation mechanism. For example, in an individual who goes to a high altitude and lives there for a while, depending on the reduced amount of oxygen in the environment, the body produces more red blood cells over time and keeps the transportation of the necessary oxygen at a normal level. This may also occur in individuals who smoke or in patients diagnosed with COPD. However, elevated hematocrit may also be pathological. It could also be a sign of a serious illness. Although rare, this can be seen especially in bone marrow diseases. Individuals with high hematocrit should not panic immediately. It should be known that physiological causes are more common. Therefore, the lifestyle of the patient and the knowledge of the chronic diseases accompanying the patient facilitate the diagnosis process.

What are the symptoms of high HCT (hematocrit)?

Symptoms of high hematocrit: Although the symptoms are very faint in many patients, especially in patients with borderline high hematocrit, complaints such as redness on the face and hands, headaches, itching sensation especially after taking a shower and tinnitus can be seen as a result of increased red blood cells in patients with higher hematocrit values.

What should be done to decrease or increase the HCT (Hematocrit) value?

If hematocrit is not within normal limits as an adaptation mechanism due to a physiological cause, then there is no need to take action. However, if the low or high hematocrit is due to an underlying disease, then treatment of that disease is necessary. For example, if there is anemia due to iron deficiency that we frequently encounter under low hematocrit values, it is necessary to treat it with iron replacement. Or, if there is a non-physiological condition in which high hematocrit values are detected, for example, if there is an underlying bone marrow production problem, a treatment plan should be made by specialist physicians.