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 D- mother 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