Hematocrit PDF

hematocrit or packed cell volume  HEMATOCRIT (PCV OR HCT) The hematocrit blood test determines the percentage of red blood cells (RBC's) in the blood. Blood is composed mainly of red blood cells and white blood cells suspended in an almost clear fluid called serum. The hematocrit test in...

hematocrit or packed cell volume  HEMATOCRIT (PCV OR HCT) The hematocrit blood test determines the percentage of red blood cells (RBC's) in the blood. Blood is composed mainly of red blood cells and white blood cells suspended in an almost clear fluid called serum. The hematocrit test indicates the percentage of blood by volume that is composed of red blood cells.  Normal hematocrit value Hematocrit is the percentage of red cells in blood. Normal levels of hematocrit for men range from 41% to 50%. Normal level for women is 35% to 50%. A low hematocrit means the percentage of red blood cells is below the lower limits of normal (see above) for that person's age, sex, or specific condition (for example, pregnancy or high-altitude living). Another term for low hematocrit is anemia. Causes of low hematocrit, or anemia, include: Bleeding (ulcers, trauma, colon cancer, internal bleeding) Destruction of red blood cells (sickle cell anemia, enlarged spleen) Decreased production of red blood cells (bone marrow supression, cancer, drugs) Nutritional problems (low iron, B 12, folate and malnutrition  A high hematocrit means the percentage of red blood cells in a person's blood is above the upper limits of normal (see above) for that person's age, sex, or specific condition (for example, pregnancy or high altitude living). Causes of a high hematocrit include: Dehydration (heat exhaustion, no available source of fluids) Low availability of oxygen (smoking, high altitude, pulmonary fibrosis) Genetic (congenital heart diseases) Erythrocytosis (over-production of red blood cells by the bone marrow or polycythemia vera) Cor pulmonale (COPD, chronic sleep apnea, pulmonary embolisms)