Blood Transfusion Flashcards
why transfuse blood?
bleeding
failure of production
Blood types - 4 main categories
A
B
AB
O
what blood groups are codominant and which are recessive?
A and B are codominant
O is recessive
which blood group type is a non-functional allele?
O
which blood group can blood type O donate to?
all types
which blood group can blood type A donate to?
A and AB
which blood group can blood type B donate to?
B and AB
which blood group can blood type AB donate to?
AB
what do you screen for in a blood donor?
‘behavioural’ screening
sex, age, travel, tattoos
Hep B/C/E, HIV, Syphilis
indications for a red cell transfusion:
correct severe acute anaemia
improve QoL
prepare for surgery/ speed up recovery
reverse damage caused by patients own cells (sickle cell disease)
if the mother has Rh negative blood cells and the baby has Rh positive blood cells - what is the risk?
what is this risk called?
the mother might develop Anti-D antibodies to the baby and give the baby haemolytic anaemia
sensitisation
what is haemolytic anaemia?
blood cells are destroyed faster than they are made
what situations would you give a platelet transfusion?
massive haemorrhage
bone marrow failure
prophylaxis for surgery
cardiopulmonary bypass
what does A/B/O etc mean??
what does +/- mean?
A/B/AB/O are your blood types
+/- is your rhesus status
when the antigen is ON the red blood cell- what rhesus status are you?
positive
when there is NO antigen on the red blood cell - what rhesus are you?
negative
what would happen if the mother is rhesus positive and the baby is rhesus negative?
nothing - mother has the antigen so there is no need to treat anything
what would happen if the mother is rhesus negative and the baby is rhesus positive?
the mother may attack the babies positive antigen on the RBC
when would a rhesus negative mother attack a rhesus positive baby?
miscarriage at 12 weeks
birth
bleeding from placenta (possible abdominal trauma)
(next baby!)
how do you treat rhesus negative mothers?
give them anti-D immunoglobulins
when do you give anti-D immunoglobulins to rhesus negative mothers?
when they miscarry at 12 weeks ish
birth
bleeding from placenta
(anytime baby and mothers blood might come into contact!)
routinely at 28 weeks
why give anti-D immunoglobulins to rhesus negative mothers?
to destroy all baby’s blood in the mother - to ensure the mothers antibodies doesn’t attack the baby’s blood cells
what could happen to the baby if a Rhesus negative mother is not treated with anti-D immunoglobulins?
haemolytic anaemia
jaundice (increased bilirubin)
(haemolytic disease of the newborn)
how do you give anti-D immunoglobulins to a mother?
you give her an IM injection
when a rhesus negative mother attacks a rhesus positive baby’s blood cells (by producing anti-D antibodies!) - what is this called?
sensitisation
what does coombs test reveal?
haemolytic anaemia
it shows antibodies on the surface of the red blood cell
(pregnant women get this test!)
when is Anti-D immunoglobulins given to pregnant rhesus negative women?
routinely at 28 weeks gestation
