Blood groups and transfusions Flashcards
(27 cards)
What is the life span of red blood cells?
120 days
What are main antigens on RBC?
ABO
Rhesus
What percentage has blood groups? Antibodies?
A dominant- 40% anti-B antibodies
B dominant- 12% anti-A antibodies
AB- 3% universal acceptor no antibodies
O- 45% universal donor no antigens but both
anti-A and anti-B antibodies
What is the universal acceptor?
AB- no antibodies
What is the universal donor?
O- no antigens
- both anti-A and anti-B antibodies
What are ABO antigens made from?
Carbohydrates
Where is IgM antibody made?
Spleen
What antibody can’t cross placenta?
IgM can’t cross placenta
Rhesus (IgG) can cross placenta
Blood type A will have what antigens?
What antibodies?
A
Anti B antibodies (attack B)
Blood type AB will have what antigens?
A, B
What anti anti-bodies will A,B have?
None
What anti-anti bodies will O have
A,B
What blood can receive if you are type A?
A,O
What type of blood can you recieve if B blood?
B,O
What blood can AB blood recieve?
A,B,AB,O
Universal acceptor
What blood can O receive?
O
Universal donor
https://www.youtube.com/watch?v=Amn2EWTY2Lk
https://www.youtube.com/watch?v=Amn2EWTY2Lk
If rhesus negative
Create D antibodies
Can’t receive positive blood
Need negative blood
What is rhesus antigen?
Series C, D, E
D/d most important
D- dominant- null gene so no protein
- no affect
What percentage of population are rhesus negative?
15%
What is rhesus disease?
Haemolytic disease of foetus and new born
(HDFN)
Explain rhesus disease?
Mother’s antibodies attack baby’s erythrocytes
If Mother is D but father gives rhesus D positive baby.
Baby’s rhesus D positive antigens cross placenta- mother make rhesus D antibodies that destroy RBCs of the baby
Baby becomes anaemic
Treatment of rhesus?
Anti-D immunoglobulin injections
Prevents mother making own anti-D immunoglobulins
Mother has already developed anti-D antibodies previous pregnancies- harder to use injection
Antenatal screening during pregnancy
Test for rhesus antigens in pregnant women Prevent sensitisation by giving anti-D to D negative mothers.
Exposure Rhesus D positive antigens?
1) Women rhesus negative (dd)
2) Get exposed foetal rhesus positive (DD/Dd)
antigens
3) Make IgG anti-D
4) Anti-D IgG crosses placenta and haemolytic
babies RBCs
5) Result in in-utero death, still-birth, brain
damage, deafness, and blindness
6) Requires in-utero blood transfusion
