Summary Fundamentals of Blood Transfusion

Blood Transfusion
Right blood, right patient




Blood Groups (ABO)




 ABO incompatible blood will cause massive intravascular haemolysis-> Fatal

, RhD Antigens
RhD Positive
 85% of the population
 Carry the RhD antigen
 Patients can receive RhD negative or RhD positive red cells
RhD Negative
 Lack of the RhD antigen
 Patients can make immune anti-D if exposed to RhD positive red cells

Immune anti-D Antibodies
 IgG-> Cross the placenta
 Do not cause direct agglutination of RBCs
 Cause delayed haemolytic transfusion reaction
 There are other Rh antigens: C, c, E and e

Many Other Blood Group Antigens
 Examples: Kell (K), M, N, S, Duffy (Fy), Kidd (Jk)
 Generally only matched for these if patient has corresponding antibody

RhD Negative Cells
 Can be safely given to anyone
 Often in short supply
 In emergencies/shortages-> use RhD positive blood in a RhD negative
 This does not generally cause acute problems-> Sometimes induces the formation of anti-D
 This can be picked up next transfusion-> Will require RhD-
 RhD negative women exposed to Rh+ blood can produce anti-D-> Haemolytic disease of the
newborn, severe foetal anaemia, and heart-failure (hydrops fetalis) in pregnancy

Grouping and Transfusion
 Blood group is done before every transfusion
 Use known anti-A, anti-B, and anti-D reagents against patient’s RBCs
 ‘Revere group’: Known A and B group RBCs against patient’s plasma (IgM antibodies)
 Positive= Agglutination
 Negative= Red cell stay suspended
Column Agglutination Technology
 Automated
 Manual
 Room temperature
 10 minutes




Automated Blood Grouping and Antibody Screening
 Bar coded samples