Blood Grouping Flashcards
What are the 2 types of stem cells in the blood?
Lymphoid and Myeloid
Name a type of Lymphoid stem cell
Lymphocytes
Name the 6 types of Myeloid stem cells
Erythrocytes Monocytes Platelets Neutrophils Eosinophils Basophils
What are the 4 constituents of plasma?
Water
Electrolytes
Plasma proteins (e.g. albumin, fibrinogen)
Substances transported (e.g. nutrients, waste products, gases)
What are the components of blood and what percentage of the blood do they cover?
Plasma 55%
Formed Elements 45%
Describe the process of blood cell production
- Process called Erythropoiesis
- Hormone involved called Erythropoietin, produced in the kidneys (or liver in foetus)
- Erythrocytes formed from red bone marrow and have a life span of 120 days
- RBC are destroyed in the reticuloendothelial system and mature RBC are enucleated
What does enucleated mean?
Absence of a nucleus
Describe the process of regulating RBC production rate
If levels of oxygen are low, kidneys release erythropoietin which stimulates the red bone marrow to enhance erythropoiesis
Give 3 reasons why there may be a low oxygen level in the blood
- Decreased RBC count
- Decreased amount of Hb
- Decreased availability of oxygen
What are the 3 main functions of blood?
- Distribution
- Regulation
- Protection
In a centrifuged blood sample, what does the buffy coat situated between the formed elements and the plasma contain?
Leukocytes and platelets
What determines whether blood is group A, B, AB or O?
The antigens on the surface of the RBC
What is another name for antigens?
Agglutinogens
What type of molecules is an antigen?
Glycoprotein
What antibodies are in the blood of group A?
Anti-B
What antibodies are in the blood of group B?
Anti-A
What antibodies are in the blood of group AB?
None
What antibodies are in the blood of group O?
Anti-A and Anti-B
What determines whether the blood is positive or negative?
The presence or absence of the rhesus antigen.
Present = positive
Absent = negative
What is another name for antibodies?
Agglutinins
What are the 3 types of antibody?
Anti-A
Anti-B
Anti-D
Why are the antibodies in blood not complementary to the RBC antigens?
Because they would react together and break down RBC
What is unusual about antibodies?
They have 2 attachment sites
Are A, B and O antigens dominant or recessive?
A and B are co-dominant
O is recessive
Describe the agglutination reaction
- RBC clump together due to an antigen-antibody reaction
- Agglutination is the splitting of donor’s RBC
- Splitting of RBC = haemolysis
Describe the relationship between the donor’s blood and the recipient’s blood.
- If donor antibodies react with recipient antigens, there is minimal damage as the antibodies are diluted in the recipient’s circulation; this is called the Dilution Effect
- If donor antigens react with recipient antibodies, this can be fatal
What is cross-matching?
Testing donor’s RBC for agglutination using recipient’s serum; the result is compatibility (remains clear) or incompatibility (goes cloudy/ clumpy)
What type of donor blood can group A receive?
Group A or O
What type of donor blood can group B receive?
Group B or O
What type of donor blood can group AB receive?
Group A, B, AB or O
What type of donor blood can group O receive?
Group O
What are the 10 steps of a blood transfusion process?
- Blood request
- Patient’s sample collection
- Blood grouping
- Cross-matching
- Blood component stage
- Pre-admin precautions
- Admin of blood components
- Monitoring during admin
- Adverse transfusion reaction
- Management of adverse reaction
What blood should be used in an emergency as the least likely to cause a reaction?
O negative
What blood type is given to rhesus positive and negative patients?
Rhesus positive = positive or negative
Rhesus negative = negative only
Why are some pregnant women given anti-D?
- Given to women who are rhesus negative
- Blood type of baby is unknown and if baby is rhesus positive, mother and baby’s blood would mix and mother would make anti-D antibodies to break down baby’s RBC
- Anti-D antigens given in injection to ‘mop up’ anti-D antibodies
How is blood tested for rhesus positive or negative?
Anti-D antibodies are added - if there is a reaction, blood is rhesus positive
