Blood Transfusion Flashcards
Chart of the ABO system
Frequency of ABO in population
O- 46%
A - 43%
B - 8%
AB - 3%
How are A and B antigens formed
Adding one or other sugar residue onto a common glycoprotein and fucose stem
Group O has neither A or B sugars
How are antibodies determined in terms of genes
What happens when an incompatible tranfusion is given
What are the genes for RhD group
Chart of the RhD antigens
How can you make anti-D antivodies
Exposed to antigen by transfusion or pregnancy
Implications of anti-D antibodies
Patient most have RhD negative blood in future - can cause delayed haemolytic transfusion reaction, anaemia, high bilirubin, jaudice
Haemolytic disease of the newborn, mothers IgG anti-D antibodies can ccross the placenta attached to the RhD positiv red cells and cause
How to avoid sensitisation of RhD negative patients
What are other red cell antigens
How to test patients before transfusion
ABO and RhD blood groups
Antibody screen on patient’s plasma
Patients plasma incubated with 2 or 3 different screening red cells
If antibody screen is negative any donor blood is given
If antibody screen is positive, antibody must be identified using large panel
How to select donors
Volunteer unpaid
17-70
Cardiovascular/neurological disease might be hazardous for donor
Viral, bacterial or parastic infections, diseases and drugs might be hazardous for recipient
Must have education and self-exclusion of individuals who are at high risk
Test undertaken on blodo donations
No test can pick u pall infections
What is the risk of prions disease
variant Creutzfeldt-Jacob disease (CJD) are found in membranes of lymphoreticular tissues
Prion proteins found in membranes of lymphocytes
Why is blood separated
Most patients only need one components
Red cell transfusion for anaemia, dont need excess fluid as it puts them at risk of fluid overload
Red cells bottom, platelets middle, plasma top
Squeeze each layer into satellite bags and cut free (closed system)
What blodo component is needed to replace coagulation factors
Fresh Frozen Plasma
Can the formation of anti-D body be prevented
Yes if the mother is given some anti D antibody
