Voluntarily have your blood drawn to use for transfusions or other biopharmaceutical processes and you are now a blood donor. You can donate whole blood (WB) or specific components. Most blood donors are unpaid volunteers who take advantage of Red Cross Blood drives and family members often donate blood to help other family members. There are also those who are paid for their donations via direct cash monies or time off from work.
Before donating blood, there is a screening process to determine if your blood is safe to use. Testing involves looking for diseases that can be transmitted to someone else. Suspect diseases include HIV and viral hepatitis. Donors must also answer questions about medical histories, take a physical examination and sign a release. Frequent blood donors are asked to wait eight weeks between whole blood donations. If you are only donating platelets, you can give blood every three days.
Donation methods can vary. You can sit in a comfy chair and have the collection done manually or go into a clinic with automated equipment that only takes specific components of your blood.
Most components of blood for transfusions have a short life and maintaining a constant supply of a particular type of blood can be a problem. It is becoming increasing popular to autotransfuse or use the patient”s own blood during surgery for reinfusion. Basically you self-donate your blood prior to surgeries.
Blood testing is done to determine the donor”s blood type. The collection agency identifies if the blood is type A, B, AB, or O and the donor Rh type will be screened for antibodies. There will be a cross match test done before a transfusion to insure all antibodies are compatible. Most blood donors are tested for Hepatitis B surface antigens, antibodies to Hepatitis C, and antibodies to HIV plus a serologic test for syphilis. Local requirements may test for other possible transmitted infections in the donor”s blood. Additional testing can be expensive and often important tests are not done due to cost.
Those with O group blood are considered universal donors when donating whole blood. Those with type AB are universal donors for plasma transfusions.
- For whole blood donations, blood is taken from a major vein. After the blood is taken, it is separated into parts or red blood cells and plasma. Generally a pint of blood is taken from the donor. (The human body averages about eight pints of blood for a normal size male and five pints for average sized females.)
- You may have blood drawn by using a filter or a centrifuge. The desired part of the blood is removed and the rest returned to the donor. This is called apheresis and is done with a machine specifically designed for blood separation.
- Direct transfusions involve blood that is not stored but is pumped directly from the donor into the recipient. This was an early method for blood transfusion but is rarely used in modern day medicine. There are too many problems with logistics, passed diseases, infections and cost.
- Blood is usually drawn from an arm vein close to the skin. The median cubical vein on the inside of the elbow is the preferred collection site. Your skin (covering the vessel) is washed with an uncontaminated wipe to prevent bacteria from polluting collected blood. A larger gauge needle is employed to prevent the cutting forces that can damage red blood cells will moving through the needle. Often tourniquet above the elbow is used to increase the blood flow through the vein.
- Collected blood can be stored in a blood bank as separate components or as whole blood. Plasma and platelets are often separated for storage, use, supply and demand.
You as a donor might just receive outside benefits from donating your blood. There is the altruistic feeling of contributing to a cause plus there are positive health benefits from your blood donations. You might just find that your blood pressure, blood glucose, HbA1c is lowered and your heart has definite improvements in beat and stability. Donating blood might just reduce the risk of heart disease for certain men and women. Studies indicate, however, that this reduction may be due to the screening that takes place before you donate your blood.