For example, since a person with Type AB blood makes no antibodies against Type A or Type B cells, his or her plasma can be given to a person with Type A, Type B, Type AB, or Type O blood. Similarly, a person having the RhD antigen will not make antibodies against RhD antigen, but the RhD negative person will make antibodies against blood with RhD positive red cells.Īntibodies in the plasma of donors with different blood types cause a reverse situation. That means that if this person is given either type B red blood cells or type AB red blood cells, his or her antibodies will attack and destroy the foreign red cells possessing the B antigen, causing a transfusion reaction. For example, if a person has type A blood, he (or she) will make antibodies against the B antigen, but not against the A antigen. Persons with a given antigen do not make antibodies against their own antigen, but will against the other antigens in that group. Persons who are RhD negative have no RhD antigen. Blood types are referred to as Type A, Type B, Type AB (which has both A and B antigens), or Type O (which has neither A or B antigens) followed by positive or negative, which indicates the presence of the RhD antigen.

The presence of antigens within these groups is what determines a person’s blood type. Humans have 35 major groups or families of these antigens, as well as other minor groups, but consideration of two, the ABO group and the RhD group, is very important to ensure that a transfusion recipient receives compatible blood. On their surface, red cells have inherited chemical structures called antigens that can cause a person’s immune system to make antibodies against them. By strictly adhering to standardized procedures, these risks have been reduced to a minimum. Risks for a person receiving blood can be divided into several categories, which include reactions due to incompatible blood types, allergic reactions, and infections in the donated blood. Minor bruising at the needle site may also occur. This can be minimized by requiring the donor to wait a short period of time after donation before standing, and to eat and drink fluids before leaving the donor area. Fainting is typically the most significant complication encountered. At least eight weeks between donations are therefore required for whole blood donations.Ĭomplications of blood donations are uncommon and usually minor. The donor will produce replacement fluid for the blood donation within 24 hours and red blood cells in four to six weeks. This is normally well tolerated by the donor, since the average donor’s blood volume is about 11 pints.

If the donor is found suitable for donating blood, approximately one pint of blood is collected from an arm vein into a plastic bag. A simple laboratory measurement is used to make sure that the blood donation will not make the donor anemic. This physical will also look for signs of any of the blood-transmitted diseases that might increase recipient risk. A simple physical, including blood pressure, pulse rate, and temperature, is used to rule out other risks. Donors are asked about their general health, as well as their travel history and possible past exposure of blood-transmitted diseases, such as HIV, malaria, and hepatitis. The donation process begins with a screening procedure to determine if the donor is healthy and has no conditions that would make his or her donation hazardous. As a result, blood banks place great emphasis on making the donation process pleasant, convenient, and as safe as possible for donors. Because a safe, reliable source of blood is critical to providing effective blood products to recipients, blood banks are dependent on the altruistic voluntary donations of citizens. Since the institution of blood banking, safety for both donors and blood recipients has been continually and significantly improved. Donation Procedure and Donor Safety - Whole Blood Donations

Diet according to blood type o negative