What is blood?
It is a liquid living tissue which flows in the heart, arteries, capillaries and veins carrying nourishment, oxygen, and many other substances to the various tissues of the body.
What are the components of blood?In the body 55% of blood consists of a liquid called plasma. The remaining 45% comprises of cellular elements. These cells are of three types- red blood cells which carry oxygen, white blood cells which fight against infections and platelets which prevent bleeding specially from small vessels.
What are red blood cells?
These are most recognizable component of whole blood. Red cells contain hemoglobin, which binds to oxygen in the lungs and carries it to each and every cell within the body.Hemoglobin also gives red color to the blood. The percentage of blood volume composed of red blood cells is called hematocrit . These are produced in bone marrow and continuosly broken down. The average life span of a red blood cell is 120 days.The red blood cells are prepared from whole blood by removing the plasma.
What are white blood cells?
White cells unlike red cells are colorless and consist of five different types of cells called, neutrophils, eosinophils, basophils, lymphocyte and monocyte. The majority of white cells are also produced in the bone marrow and live for 6-7 hours to several years depending on the type. The granulocytes are collected from the whole blood by a technique called apheresis.
These are the smallest cellular component of blood.These are also made in the bone marrow and survive for 9-10 days in the circulation. Units of platelets can be prepared by using a centrifuge to separate platelet rich plasma from whole blood and platelets are then concentrated by further centrifugation of platelet rich plasma.Platelets can also be obtained from a donor by process of apheresis or plateletapheresis.
What is plasma?
This is the liquid part of blood. Plasma is a protein salt solution in which various blood cells are suspended. It consists of about 90% water. The main plasma proteins are albumin, fibrinogen and globulins.It also contains various clotting proteins.Plasma is obtained by separating the liquid portion of cells. Plasma can be fractionated into specific products like albumin, clotting factors, immunoglobulins etc. This is usually done in plasma fractionation units which is not available in Mauritius.
Who benefits from transfusion of various blood components?
Red blood cells are transfused mostly to patients of anemia which may be due to various causes. However if cause of anemia is treatable e.g iron deficiency, then it is best to treat this rather than transfusing blood. Platelets are usually given to patients who have decreased number of platelets or impaired platelet function. Plasma is used for treating clotting factor deficiencies when such factors are not available.