15 Blood Groups

  • ABO: natural antibodies
  • Rh: acquired

  • not naturally occuring

ABO

  • formation of A and B driven by exposure to bacterial antigens
  • do not cross placenta: no problem for different babies and mom

  • 4 sugar molecules
  • O: H antigen, default
  • A: add galactosamine

Rh

  • in contrast with sugar on surface

  • antibody does not occur naturally like ABO

Newborn Hemolytic Disease

  • antibodies from mom cross placenta, attack baby

  • low antibody titer: mild case

  • screen Dmother for antibodies to antigen

  • D+ RBC from fetus to maternal circuit, IgG binds
  • clearance before immune response

Transfusion

  • Type and screen: determine AB, Rh antigens and perform antibody screening test for rare antigens

Blood Type

Type and Screen

  • screen for antibodies to rare antigens
  • further testing to determine which antigen

  • many transfusions in life: many different antibodies

Type and Cross

Blood products

  • FFP: for clotting factors

Transfusion reactions

  • reason for typing and cross matching

  • leukoreduction: eliminate WBC to reduce frequency of FNHTR

  • inflammation in lungs
  • neutrophils in patient's lung exposed to product and activated to release enzymes

  • answer always stop transfusion first