What Are Blood Components?
Blood is a body fluid circulating, delivering oxygen and nutrients to the body cells. Blood cells are produced inside the bone marrow (a spongy material present in the center of the bones that is responsible for making all types of blood cells). The different components of blood include
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Plasma - It is the largest part of the blood, making more than 55 percent of the overall blood content. Plasma appears as a light yellow liquid when separated from the blood. It mainly consists of water (92 percent), vital proteins like albumin, gamma globulin, anti-hemophilic factor, mineral salts, sugars, fats, hormones, and vitamins. Plasma serves important functions, like maintaining blood pressure and volume, supplying vital proteins required for blood clotting, carrying electrolytes, like sodium and potassium, to the muscles, and also helping in maintaining pH balance in the body.
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Red Blood Cells (RBC) - It is also called erythrocytes; they are an important element of the blood. Each RBC has a biconcave shape, contains hemoglobin, and only lasts 120 days. They are responsible for delivering oxygen from the lungs to the peripheral tissues, collecting carbon dioxide, and returning it to the lungs for elimination from the body. In addition, RBC allows gas exchange and transport between the lungs, blood, and tissues. A deficiency of red blood cells can lead to different types of anemia, causing symptoms like tiredness, fast heart rate, pale skin, and cold hands and feet.
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White Blood Cells (WBC) - These account for only about one percent of the blood. However, it plays an important role in protecting against illnesses and diseases. WBCs are also known as leukocytes and travel through the bloodstream to fight bacteria, viruses, and other foreign invaders. WBCs have five types: monocytes, lymphocytes, neutrophils, basophils, and eosinophils. Several diseases and conditions can cause low white blood cell counts, such as a weak immune system, infections, blood cancer, and certain medicines.
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Platelets - These are tiny blood cells that help the body to stop bleeding after an injury and form clots. Platelets or thrombocytes are colorless, tiny cell fragments formed in the bone marrow. They cluster together at the site of the injury to form a clot, acting as a plug to seal the site of the wound. There is about one platelet for every 20 red blood cells in the body. In adults, normal platelet count ranges from 150,000 to 450,000 platelets per microliter of blood. Certain types of anemia, leukemia, or lymphoma can cause a low platelet count.
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Cryoprecipitate - Called cryo. It is a portion of plasma rich in clotting factors, fibrinogen, factor VIII, and von Willebrand factor.
What Is Blood Component Transfusion?
Blood component transfusion is a life-saving technique in which donated blood is used to replace blood lost due to surgery, disease, bleeding disorders, or injury. It is a routine medical procedure that helps to replace a key component of whole blood in a patient's bloodstream through a vein. Another person may donate the blood or have it taken from a patient and stored until needed.
How Are Blood Components Prepared for Transfusion?
Whole blood consists of a mixture of colloids, cellular elements, and crystalloids. It can be separated into different components: packed red blood cells concentrate, platelet concentrate, fresh frozen plasma, and cryoprecipitate (a portion of plasma). Each blood component is used for different indications; thus, the component separation has been maximized for the proper utility of the whole blood unit. Different components need different temperatures and storage conditions for their therapeutic efficacy. Also, the blood component to be transfused, being foreign to a patient, may produce adverse effects, ranging from mild allergic reactions to fatal reactions. To avoid such complications, blood products are modified. The components are made by centrifugation of one unit of whole blood. Once collected in a bag, the whole blood should be separated within five to eight hours. All precautionary measures must be taken to avoid contamination. Standards protocols described in the manual of the refrigerated centrifuge manufacturer, like tapping the segment ends, and proper balancing of opposite bags, must be observed.
What Are the Different Blood Component Products?
These are classified as blood components prepared in the blood transfusion center and include
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Whole Blood - Itcontains white blood cells, red blood cells, and platelets suspended in blood plasma. It has a shelf life of 21 to 35 days and can be refrigerated. It is usually used in patients with trauma or surgery. Whole blood transfusion is the simplest and most common type of blood donation. It might be transfused in its original form or separated into specific components to help multiple people.
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Packed Red Blood Cells - These are prepared from whole blood by removing the plasma. They have a shelf-life of up to 42 days, depending on the type of anticoagulant used. Red blood cells can be treated and frozen for ten years or more.
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Platelets - These can be prepared by separating the platelet-rich plasma from the donated whole blood using a centrifuge. Platelets can be stored at room temperature for up to five days. However, care must be taken to constantly agitate them to prevent them from clumping.
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Plasma - It can be obtained by separating the liquid portion of the blood from the cells. Plasma is frozen within 24 hours after donation to preserve its clotting factors. It can be stored for up to one year. It is commonly transfused to trauma, burns, and shock patients. Some patients may need plasma derivatives that are concentrates of specific plasma proteins, like factor VIII concentrate, factor IX concentrate, albumin, immunoglobulins, antithrombin III concentrate, or alpha 1-proteinase inhibitor concentrate.
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Cryoprecipitate Antihemophilic Factor- It is a part of plasma rich in fibrinogen clotting factors, including factor VIII. They can be prepared by freezing and then slowly thawing frozen plasma. It can be stored for up to a year.
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White Blood Cells - They are often removed from transfusable blood components. This is because leukocytes carry viruses that may cause immuno-suppression and release toxic substances in the recipient. However, granulocytes, a type of white cell, can be collected by an automated process called apheresis and transfused into the patient within 24 hours of being donated.
What Is the Process of Blood Component Transfusion?
Blood transfusion involves the process of receiving blood or blood products intravenously. It is carried out at a hospital or a blood donation facility. Before the procedure is started, a nurse or a doctor will check the patient's blood pressure, pulse, and temperature. It is important to check the blood type during blood transfusion, or else the body may reject the new blood. Then, an intravenous line (IV) is placed into the patient's body, usually in the arm, through which the patient will begin to receive the new blood. A simple blood transfusion can be done between one to four hours, depending on the amount of blood. Following the completion of the procedure, the patient's vital signs are again checked. Recovery time might be based on the reason for the blood transfusion, but it is usually at most 24 hours after the procedure.
What Are the Possible Risks of Blood Component Transfusion?
The use of blood components can cause adverse reactions. It can be immune-mediated adverse reactions, causing allergic reactions, anaphylactic reactions, transfusion-related damage to lung tissue, or delayed destruction of red blood cells. Non-immune mediated adverse reactions may also occur, causing bleeding problems, fluid overload, the reaction from extra potassium in the blood, or lower calcium levels. An infection can also occur from bacteria or virus-contaminated blood components.
Conclusion:
Blood is important, and not having enough of each blood component can cause life-threatening conditions. Blood transfusion is a life-saving technique and is usually indicated in cases of surgery, injury, disease, or bleeding disorders. Blood transfusion usually occurs without complications. However, it may cause allergic reactions and blood-borne infections, like hepatitis B or C and human immunodeficiency virus (HIV). Discuss with the healthcare provider to ensure the safety of these treatments by screening donors.
