Blood transfusion Flashcards
Know the main components of blood that can be transfused + their indications
Understand why blood groups restrict how blood can be transfused
Understand when to send samples to blood bank, the principles of what happens to samples within the lab and when/how blood is made available
Know the main hazards of blood transfusion
Understand the pathophysiology of haemolytic disease of the newborn and how it is prevented
Be aware of future cellular therapies
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Name the 4 blood groups
Each group can be either … or …
A, B, AB and O
RhD +ve or RhD -ve
Following blood group have antibodies against which other blood group
- A
- B
- O
- AB
If blood group A, have antibodies against B (anti-B [antibody against antigen B])
If blood group B, have antibodies against A
If blood group O, have antibodies against A and B
If blood group AB, have no antibodies against A and B
Anti-A and anti-B antibodies are usually which type of immunoglobulin
IgM
AB blood type as well as being able to receive donor blood types AB and O, these people can also receive from A and B blood type donors
Why is this?
Because AB blood has no antibodies against A and B antigens
Do the blood donor compatibility rules apply with fresh frozen plasma
No
A type blood can receive FFP from A and AB
B type blood can receive FFP from B and AB
AB type blood can receive FFP from AB type only
O type blood can receive FFP from ALL
RBCs may have another antigen in addition to its A/B/O/AB antigen, what is this?
RhD
RhD positive individuals make what antibody
Anti-D immunoglobulin
Why is anti-D relevant in pregnancy
If anti-D antibodies are detected in your blood during pregnancy, there’s a risk that your unborn baby will be affected by rhesus disease
Rhesus disease only happens when the mother has RhD negative blood and the baby RhD positive. The mother must have also been previously sensitised to RhD positive blood.
Sensitisation happens when a woman with RhD negative blood is exposed to RhD positive blood, usually during a previous pregnancy with an RhD positive baby. The woman’s body responds to the RhD positive blood by producing antibodies
If sensitisation occurs, the next time the woman is exposed to RhD positive blood, her body produces antibodies immediately. If she’s pregnant with an RhD positive baby, the antibodies can cross the placenta, causing rhesus disease in the unborn baby –> SEVERE ANAEMIA IN THE BABY
Donor blood is always screened for what diseases
Hep B/C/E,
HIV,
Syphilis
Indications for RBC transfusion (over 2-4 hours)
To correct severe acute anaemia, which might otherwise cause organ damage
To improve quality of life in patient with otherwise uncorrectable anaemia
To prepare a patient for surgery or speed up recovery
To reverse damage caused by patient’s own red cells
Components of blood that can be transfused
RBCs
Platelets
Plasma - fresh frozen plasma, cryoprecipitate
Indications for platelet transfusion (over 20-30 mins)
Massive haemorrhage
Bone marrow failure (if platelets <10-15 x …)
Prophylaxis for surgery
Cardiopulmonary bypass
What is the Coombs test
To detect antibodies that act against the surface of yourRBCs
Presence of these antibodies indicates a condition known as haemolytic anemia, in which yourblooddoes not contain enoughRBCs because they are destroyed (testing for AUTOIMMUNE HAEMOLYTIC ANAEMIA)
How to prevent haemolytic disease of the newborn (HDN), i.e. rhesus disease
Anti-D immunoglobulin prophylaxis to all pregnancy women at 28wks gestation
