Blood groups and transfusions Flashcards
(14 cards)
What are the 4 possible blood types?
A, B, AB, o
If someone has the phenotype o what is their genotype?
oo
If someone has the phenotype A what is their genotype?
AA or Ao
If someone has the phenotype B what is their genotype?
BB or Bo
If someone has the phenotype AB what is their genotype?
AB (they are co-dominant)
What is the genotype of someone who is rhesus negative?
dd
What is the genotype of someone who is rhesus positive?
DD or Dd
What happens if a rhesus negative mother has a rhesus positive baby?
Mothers immune system produces IgG anti-D. This Anti-D crosses the placenta and haemolyses the babies red blood cells
How is the problem of a rhesus negative mother giving birth to a rhesus positive mother combated?
Mother is injected with Anti-D which destroys any red blood cells from the baby that have passed across the placenta preventing the mothers immune system from undergoing an immune response so no production of Anti-D by the mother.
What percentage of the population is rhesus negative?
~15%
What 2 tests are done to determine blood group and what are the results?
Using antibodies (Anti-A and Anti-B) If o = reacts with neither. If A = reacts with Anti-A If B = reacts with Anti-B If AB= reacts with Anti-A and Anti-B
Or using serum: o serum = contains Anti-A and Anti-B A serum = contains Anti-B B serum = contains Anti-A AB serum = contains neither
What is done for patients with thrombocytopenia?
Given a transfusion of platelets
What does a cryoprecipitate from fresh frozen plasma contain?
Factor VIII concentrate, fibrinogen, von Willebrand factor and fibronectin
What does a cryosupernate from fresh plasma contain?
Albumin, immunoglobulin, other concentrates
