Blood transfusion Flashcards
(38 cards)
What antibodies and antigens does a person with blood group A have?
A antigens
Anti-B antibodies
What antibodies and antigens does a person with blood group B have?
B antigens
Anti-A antibodies
What antibodies and antigens does a person with blood group O have?
No antigens
Anti A antibodies and anti-B antibodies
What antibodies and antigens does a person with blood group AB have?
A antigen and B antigen
No antibodies
Which blood group is considered to be the ‘universal donor’?
O-
Which blood group is considered to be the ‘universal recipient’?
AB+
What does is mean if someone is RhD +ve?
They have the RhD antigen
Why should people who are RhD -ve receive Rh-ve blood?
After exposure to RhD+ve blood, they can create the anti-D antibody which can cause problems with subsequent transfusions or pregnancy
What is the difference between group and save and fully crossmatched blood?
G&S - looks at ABO and RhD, avaliable within 10-15 means
Crossmatched - full antibody profile, but takes much longer
Why should donor blood be irradiated if given to an immunocompromised patient?
This will inactivate donor T cells
Active donor T cells may cause graft-versus-host disease
What is graft vs host disease?
White blood cells in the donated tissue (the graft) recognize the recipient (the host) as foreign
The transplanted immune cells then attack the host’s body cells
What is the shelf life of red blood cells and how should they be stored?
35 days
Stored at 4 degrees
What is the shelf life of platelets and how should they be stored?
5 days
Stored at 20-24 degrees on an agitation rack
What form do most naturally occurring ABO antibodies take?
IgM/pentameric form
Some IgG
What chromosome are genes that determine blood group located on?
Chromosome 9
What happens to red blood cells when e.g. there is addition of anti-A antibody to group A red cells?
They agglutinate
Other than ABO, what other blood groups need to be considered?
Kells
Duffy
Kidd
Rhesus
When do more obscure blood groups need to be considered to possibly cause disease?
Multiple transfusions - patient may have had time to develop obscure antibodies
What is the difference between direct and indirect Coombs test?
The direct Coombs test is used to detect these antibodies or complement proteins that are bound to the surface of red blood cells
The indirect Coombs test detects antibodies against RBCs that are present unbound in the patient’s serum
When is direct Coombs test used clinically?
Haemolytic disease of the newborn
Autoimmune haemolysis
Drug-induced, immune-mediated haemolysis
When is the indirect Coombs test used clinically?
Antenatal antibody screening
Blood transfusion preparation
What is the bag of blood inspected for at the bedside?
Ensure correct patient Ensure blood product in date Look for bubbles (bacterial contamination) Look for blood clots Look for haemolysis
What rise in haemoglobin would be expected with each bag of blood transfused?
10g/L
What immune response is implicated in immediate haemolytic reaction?
IgM
Activates release of C3a and C5a and forms membrane attack complex
This leads to lysis of the red cell
