Blood Transfusion Flashcards
What is the minimum criteria for haemoglobin in men and woman respectively to be eligible to donate blood?
Men: Hb 135g/L
Women: Hb 125g/L
Minimum weight 50kg
During blood processing and testing, what pathology is screened for in microbiological testing?
HIV Hep B Hep C Hep E HTLV Syphilis
List some blood products that can be acquired from batches of blood via manufacturing
Human albumin
Immunoglobulin
Prothrombin complex concentrates
AntiD immunoglobulin
List components of blood available from the transfusion lab
Red cells
FFP
Platelets
Cryoprecipitate
What must be done to donor blood to separate it into components?
Anticoagulation
Who should avoid donating blood?
Infective risk
Transmitting disease (malignancy)
Drug addicts
Recent foreign travel to endemic areas
Describe the order/position of blood components in a bag once blood has been centrifuged
Red cells at bottom (most dense)
Platelets + white cells in middle
Plasma at top (least dense)
Describe how blood groups are formed in the ABO system
A and B genes, one inherited from each parent, code for transferases which modify precursors called H substance on red cell membrane
What is Landsteiners law?
When an individual lacks the A or B antigen the corresponding antibody is produced in their serum/plasma
What is the shelf life of donated platelets?
7 days if bacterial monitoring system applied
At what temperature and for how long must fresh frozen plasma be stored?
-30’C for up to 3 years
What are the possible blood groups a person can be?
A
B
AB
O
Describe the red cell membranes of ABO blood groups, and the associated antibodies produced
A: carry A-antigen (anti-B antibody)
B: carry B-antigen (ant-A antibody)
AB: carry A-antigen + B-antigen (no antibodies)
O: no A or B antigen (anti-A and anti-B antibody)
Order the blood groups from highest to lowest population frequency
O, A, B, AB
Which of the ABO blood groups is the universal donor? Why?
O is universal donor because blood carries no antigen and therefore other blood groups won’t form antibody against it
Which of the ABO blood groups is the universal recipient? Why?
AB is universal recipient because it carries both antigens and therefore won’t form antibody against any of the other blood groups
Naturally occuring ABO antibodies are what - Ig?
IgM
Small proportion are IgG
The genes that determine our ABO group are located on which chromosome?
Chromosome 9
Which alleles for ABO group are dominant?
A and B are co-dominant
O is recessive
The genes that determine Rhesus-D status are located on which chromosome? How are they inherited?
Chromosome 1
Inherit D or d allele, one from each parent
Inheritance of Rhesus-D follows what pattern? What percentage of the population are RhD+
Autosomal dominant (d allele is silent) 85%
What are the risks of RhD antigen exposure? How are these prevented?
Transfusion reactions
Haemolytic disease of the fetus and newborn
Avoid exposing Rh- to D antigen through transfusion
What are the possible ways to carry out ABO grouping?
ANTISERA (ABO group)
Use reagents with known antibody specificity to identify red cell antigens:
REAGENT RED CELLS (antibody)
Use red cells with known antigen specificity to identify antibodies in plasma
How is blood group determined?
Agglutination
Giving antibody to individual of same blood type (e.g. anti-A to group A) will cause cells to stick together
