Blood Transfusion = Physiology Flashcards
How are ABO blood groups determined?
ABO gene encodes Glucosyltransferase to produce certain glycans which are added to proteins & lipids on red cells. these are the antigens denoting blood group
What surface antigen is A, B & O?
A = N-acetyl-galactosamine B = Just Galactose O = No antigen (it's gene is a non-functional allele)
How are blood groups inherited?
O is recessive
A & B are dominant
How do you decide which blood group to give when giving red cells?
The donor musn’t have any antigens (A or B) that the recipient doesn’t have or the host will attack the donor cells
So who can give/receive group A red cells?
A can give to A or AB (as they won’t react to the donor A antigen)
The can only take from A or O
Who can give/receive group B red cells?
B can give to B or AB
Can only take from B or O
Who can give/receive group O red cells?
Can donate to anyone (as no antigens)
But can’t receive from anyone but O
Who can give/receive group AB red cells?
Only donates to AB and can take from anyone
The rules for donating fresh frozen plasma are different to red cells. How do blood groups affect FFP donation?
With FFP donor must have all the antigens the recipient has (can also have extra.) But it won’t work if the recipient has antigens not present in the donor
So who can give/receive group A FFP?
Can give to A or O
Receive from A + AB
So who can give/receive group B FFP?
Can give to B or O
Can only receive from B or AB
So who can give/receive group AB FFP?
Give to A, B, AB or O (so anyone)
Can receive from AB
So who can give/receive group O FFP?
O can only donate to O but they can receive from anyone
Other than the ABO blood groups the other main grouping is RhD +ve vs RhD -ve. What’s the danger of RhD?
If RhD -ve people receive RhD +ve blood they will create Anti-D antibodies –> Transfusion reaction
How is RhD involved in maternity?
An RhD -ve mother can pass on anti-D antibodies to their newborn.
If they’re RhD +ve the newborn will develop haemolytic disease
