There are many different products made from human blood that can be transfused:
Red Blood Cells: The function of the red cells is to carry the oxygen to the vital organs to allow for survival. At present, there is no proven substitute for red blood cells. A red cell transfusion may be necessary to prevent damage to vital organs due to lack of oxygen.
Platelets: Platelets are small cells needed to prevent or stop bleeding. These sticky little cells are needed to start blood clotting at the site of injury. Platelet transfusions may be required for patients who have a low number of platelets or whose platelets do not work properly.
Plasma: Plasma contains many substances including the proteins that help blood to clot.
Albumin: Albumin is a protein from plasma than can be used to replace fluid that has been lost.
Immunoglobulin Preparations: Immunoglobulins are proteins that help fight infection. They may be given to patients with low immunoglobulin levels, or patients experiencing recurrent infections.
Whole blood is collected by Canadian Blood Services from volunteer donors. All potential donors are screened by a written questionnaire and interviewed by a nurse. This donated blood is processed into its separate components and tested for:
Human Immunodeficiency Virus (HIV 1 and 2, the AIDS viruses)
Human T Cell Lymphotropic Virus 1 and 2 (HTLV-1 and 2)
West Nile Virus
If blood is found to have any of these infections, it is disposed of and never used. Blood is never collected from an infected donor again. However, you need to be aware that blood can never be guaranteed to be 100% safe and there remains a theoretical risk of 1 in 1,000,000 risk of HIV transmission as well as a 1 in 250,000 risk of Hepatitis B or C transmission despite appropriate screening.
Everything possible is done to reduce the risks associated with blood transfusions; however, you should be aware of the possible risks:
Viral infections: Although blood products are tested for infections of known viruses, it is still possible to become infected. It is possible for a donor to carry a virus and not feel sick or to be infected but only feel sick several days later. The risks are decreasing because screening tests are improving all the time. You can get more information about the risks from your doctor.
Allergic reactions: You might feel itchy or get a rash with transfusions. However, these reactions are easily treated with antihistamines and anti-inflammatories. Rarely, allergic reactions may be severe and produce shortness of breath or throat swelling.
Fever: A reaction may occur from substances in the donor blood, which may result in a fever. This response occurs during or shortly after the transfusion has been completed. The fever may or may not require treatment. The symptoms may consist of feeling cold or chills, followed by a rapid rise in body temperature (fever). If you have had a history of fever reactions with prior transfusions, you should tell the doctor.
Hemolytic reactions: This rare reaction occurs when antibodies in the patient's blood react against the donor red cells, destroying them. This is called hemolysis and can result in kidney failure. To ensure that the correct blood is given to prevent this reaction, careful blood testing, processing and administering procedures are required.
Iron Overload: If blood product transfusion is required for an extended period of time, it is possible for the body to accumulate too much iron. This could lead to problems with liver or heart function. Once patients no longer require transfusions, blood may have to be removed from the body as medical therapy to remove iron. This procedures is called a phlebotomy. If patients with iron overload are still requiring transfusion, a drug (Desferal) can be prescribed to assist in iron excretion from the body.
Previous reactions: You should let the doctor know if you have had a reaction from blood transfusions in the past, so that steps can be taken to prevent it from recurring.
A blood sample is taken from you and sent to the hospital laboratory. Tests are performed to ensure the donor blood is compatible with the patient's blood. This process is called cross-matching. The donor blood is then labelled with your name and you will receive only that blood.
The blood, or blood product, is given to you through your Hickman® line or a needle in a vein in the arm. During the transfusion, the nurse will take your temperature, blood pressure and pulse. The blood transfusion can take from 30 minutes to a few hours to complete.
Family members sometimes ask if they can donate blood for a loved one. This is called a directed donation. In general, directed donations are not done but may be possible in special situations; for example, if the patient has a very rare blood type, or in some cases, a parent may donate for their child when the parent's and the child's blood match.
It is important to remember that directed donations are not generally available. This is because directed donations have not been shown to be safer than volunteer blood donations.
In order that staff know your wishes with regard to receiving blood or blood products, it is required that you sign the relevant consent forms:
If you are likely to need blood and/or blood products, you will be asked to complete a consent form on each admission to hospital or at the beginning of each course of treatment.
If you choose to refuse blood and/or blood products, you must complete a Refusal To Accept Form for each admission and/or each course of treatment.
If you refuse to receive blood and/or blood products at any time, you must carry an Advance Directive or other written instruction advising the medical staff. In the absence of written refusal, medical staff will give blood and/or blood products if considered necessary to preserve life or health.
If you or your families need more information, please talk to your doctor. The medical staff at the hospital's blood bank can also help.