100 likes | 141 Views
Blood Groups & Transfusions. Pages 349-353. Blood Transfusions . When blood is given intraveneously Usually donated blood Transfusions are given for: Blood loss due to injury Surgery To supplement your own blood. Compatible Transfusions. Blood cells have their own antigens
E N D
Blood Groups & Transfusions Pages 349-353
Blood Transfusions • When blood is given intraveneously • Usually donated blood • Transfusions are given for: • Blood loss due to injury • Surgery • To supplement your own blood
Compatible Transfusions • Blood cells have their own antigens • Genetically determined proteins • Allows us to determine “self”; a form of self defense • Transfusions must be compatible w/recipient • Those individuals with the same antigens
Incompatible Transfusions • What happens if the blood is incompatible? • Your body will assume the transfused blood is an invader • Antibodies will bind to the (foreign) antigens on the donor RBC • Antibodies are proteins specialized to recognize foreign substances and provide immunity against them
Agglutination follows… • Incompatible transfusions cause agglutination • clumping of the foreign RBCs • RBCs burst open!(hemolysis) • releases hemoglobin into bloodstream • Hemoglobin can block kidney tubules • Can cause kidney failure and death
Blood Type is inherited • Represented by multiple alleles • Two of these are co-dominant • The Rhesus factor is a protein that may exist on the surface of the cell – this results in a positive blood type
The Main Blood groups • The ABO Blood groups: • Type A (Both A antigens) • Type B (Both B antigens) • Type AB (Both A and B antigens) • Type O (neither antigen is present; recessive) • Rh (rhesus) factor ( + or - ): • Positive or negative for presence on the surface of the RBC • Pregnant women risk destruction of baby’s RBCs as the body attempts to reject a baby that doesn’t match mother’s rhesus factor
Pregnancy and the Rh Factor • Differences in Rh factor between baby and mother • Most of the time, the first baby is fine • Antibodies are built up after first baby • This makes the second pregnancy extremely high risk
Hemolytic Disease of the Newborn • If the baby survives pregnancy: • the destruction of RBCs will result in: • Hemolytic disease of the newborn • Jaundice • Anemia • Enlarged liver/spleen • To counteract this problem: • Incompatible mothers are given an immune serum called RhoGAM to prevent this immune response