Blood Transfusion Flashcards
(35 cards)
why can blood groups provoke an immune response?
because they arise from antigens
describe type A antigens
> N-acetylgalatosamine
> co-dominant
describe type O antigens
> non functioning allele
> recessive
describe type B antigens
> galactose
> co-dominant
what happens when a RhD -ve individual is exposed to RhD + cells?
they can make anti -D antibodies
what do ABO genes code for?
glycosyltransferase (AB genes code for the transferase enzyme and glycans are added to the proteins or the lipids on the red cell)
what blood can a group A patient receive?
> A
> O
what blood can a group B patient receive?
> B
> O
what blood can a group AB patient receive?
> A
B
AB
O
what blood can a group O patient receive?
> O
what fresh frozen plasma can group A receive?
> A
> AB
what fresh frozen plasma can group B receive?
> B
> AB
what fresh frozen plasma can group AB receive?
> AB
what fresh frozen plasma can group O receive?
> A
B
AB
O
what are the indications for red cell transfusion?
> correct severe acute anaemia
improve quality of life in un-correctable anaemia
prepare for surgery/speedy recovery
reverse damage by patients own cells
what screening questions are asked in blood donation?
> tattoos > travel > sex > age > sexual behaviour
what is always screened for in blood donation?
> Hep B/C/E
HIV
syphilis
what is variably screened for in blood donation?
> zika
malaria
west nile virus
what is group and screening?
> checking RhD type
checking ABO type
checked against historical records
screen for alloantibodies
what tests are used in group and screening?
> coombs test
> gel’s column and automation
describe the availability of red cells in hospital
> Minutes: O RhD -ve cells and AB plasma
urgent: type specific
Non-Urgent: full cross match
Massive Haemorrhage: 6 units of red cells, 1 unit of platelets and 4 units of FFP
what is haemolytic disease of the newborn?
the baby is RhD +ve and the mother is -ve so maternal antibodies antiD antibodies develop as IgG crosses the placenta.
what is neonatal alloimmune thrombocytopenia?
uncommon but it is the same process as haemolytic disease of the newborn but involving platelets.
intracellular haemorrhage
how is haemolytic disease of foetus and newborn managed?
> prevention with prophylactic anti-D at 28/40 weeks > treatment: - carful monitoring with doppler US - interuterine transfusion - antibody titres
