What is a blood transfusion?
A blood transfusion is the process of transferring blood or one of its components from one person to another. Blood is made of fluid called plasma and three types of blood cells: red cells, white cells, and platelets. Each part of blood has a special function and can individually transfused.
Plasma is the fluid in blood that carries the blood cells throughout the body. It contains proteins that help the blood clot, as well as vitamins and minerals. A plasma transfusion may be needed when a child lacks the parts of the blood that help it clot.
Red blood cells
Red blood cells are the part of the blood that carries oxygen from the lungs to all other parts of the body. A certain number of these cells are needed for the body to function. Red blood cell transfusions are the most common. A child may need a red blood cell transfusion if bleeding from a trauma, surgery, or a disease that causes a low red blood cell count.
White blood cells
White blood cells are the part of the blood that fights infections by destroying bacteria, viruses, and other germs. White blood cell transfusions are very rare. They are usually reserved for children who have a low white blood cell count and severe infection that cannot be treated with antibiotics.
Platelets are the part of the blood that helps control bleeding by forming blood clots. A platelet transfusion may be needed before an invasive procedure, such as a major surgery, that can cause a child with a low platelet count to bleed.
Why would a child need a blood transfusion?
There are many reasons why a child may require a blood transfusion, such as:
- sudden loss of blood
- low hemoglobin (part of red blood cells that helps them carry oxygen from the lungs to all the parts of the body) before, during, or after surgery
- severe heart or lung disease
- bone marrow failure
- moderate to severe anemia
- treatments such as chemotherapy, radiation therapy, and immunosuppressive therapy, which can destroy blood-making cells in the bone marrow
- red blood cell disorders, including hemolytic disease of the newborn, hemolytic anemia, thalassemia, sickle cell disease, Diamond-Blackfan anemia, hereditary spherocytosis, and rarely severe iron deficiency anemia
- certain cancers such as leukemia and digestive system cancers that cause internal bleeding
- severe heart or lung disease
How is a blood transfusion performed?
Before a child receives a blood transfusion, the blood is carefully tested and cross-matched with his own blood to make sure it is compatible. It is then given through a needle or catheter (a thin, flexible tube) placed in the vein. The child’s temperature, blood pressure, and heart rate will be monitored through the procedure. The full process usually takes a few hours to complete. Most blood transfusions are performed without any problems.
Some children, especially those with sickle cell disease, require an exchange transfusion in which the patient’s red blood cells are removed and replaced with red cells from a donor.
What are the side effects of blood transfusion?
Blood transfusion may cause mild side effects, such as:
These side effects can usually be treated with medication, should a child require additional transfusions.
Serious side effects from blood transfusions are rare. When they do occur, the most common is serum hepatitis, an infection of the liver. Although it is highly unlikely, a transfusion with the wrong type of blood can result in death.
Where does the blood used in a transfusion come from?
Blood used at most hospitals comes from volunteer donors. Before being accepted as a donor, each volunteer must provide their medical history and undergo a physical examination. The blood is collected by a needle inserted into a vein and carefully stored in sterile bags, which are used once and then thrown away.
Is the blood used for transfusions safe?
Donated blood is carefully tested for hepatitis (liver disease) and syphilis (bacterial disease), as well as two viruses that affect the immune system, including HIV. These tests decrease the chances of infection caused by blood transfusions.