Blood Flashcards
Describe the composition of blood (with percentages)
Plasma 55%
Buffy coat <1%
Erythrocytes 45%
What are the features of albumin?
Globular protein
Synthesised in the liver
Plasma concentration of 35-50mg/ml
19 day half life
60% of plasma
What is the function of albumin?
Maintains oncotic pressure
Controls pH
Binding and transport
What are the components of plasma (with percentages)?
Albumin 60%
Globulins 35%
Fibrinogen 4%
Other 1%
What are globulins and the types?
Antibodies and transport proteins
Alpha 1, alpha 2, beta and gamma
What are agglutinogens?
Specific proteins located on the RBC wall (basis for blood group classification)
What are agglutinins?
Plasma antibodies that act against agglutinogens not present on a persons own RBCs
What percentage of the population are of each blood type?
A 42%
B 10%
AB 4%
O 44%
What blood types can Type a recieve?
A/O
What blood types can type B recieve?
B/O
What blood types can Type AB recieve?
They are the universal recipient
What blood type can Type O receive?
Only O
What does rhesus group mean?
Rhesus group positive types have the rhesus antigen on the RBCs
(More common in the west than in Asia or Africa)
What is the function of fibrinogen?
Basically a clotting factor
Where do all blood cells arise from?
Haematopoietic stem cells
Where are blood cells produced?
Bone marrow
What is the process of blood cells differentiating called?
Haematopoiesis
Which types of white blood cells are derived from myeloblasts?
Basophils
Neutrophils
Eosinophils
Monocytes
What are the two responses of a transfusion reaction?
Humoral
Acute haemolytic
What happens in the haemolytic disease of the newborn?
If a rhesus negative mother is pregnant with a rhesus positive child
When there is exposure of the foetus red blood cells to the mothers red blood cells, the mothers body produces rhesus positive antibodies
Then when pregnant again with a rhesus positive child, the mothers immune system attacks the child
What symptoms does the child have if they have haemolytic disease of the newborn?
They are small and anaemic
What are the steps in primary haemostasis?
Damage to blood vessel wall
Vasoconstriction
Platelets adhere to the wall and become activated
Platelets release their granules (cont. platelet activators, coagulation factors, vasoconstrictors)
Platelet plug forms
What are the steps in secondary haemostasis?
Due to coagulation cascade fibrin cross linking occurs
When is tranexamic acid used to prevent the inhibition of clots forming?
Trauma management
Post partum haemorrhage
Define clot
General term for mass of coagulated blood
Define thrombus?
Formation of a blood clot in life and in situ
Define embolus
Detached intravascular material that is carried from origin to distant site
What are the three components of Virchow’s triad
Stasis
Vessel wall injury
Hypercoagulability
What is factor V Leiden?
It’s a thrombophilia (hyoercoagulable state)
Results from a mutant form of factor 5 resistant to protein C
So factor 5 isn’t degraded so increased risk of thrombosis
What is antiphospholipid syndrome?
It’s an autoimmune condition causes thrombophilia
Can be primary or secondary depending on whether there is a secondary condition
Compare and contrast arterial and venous thromboses
Arterial due to endothelial injury - venous due to stasis
Arterial is high pressure and high stress - venous is low pressure and low flow
Arterial is a platelet rich thrombus - venous is a red blood cell rich thrombus
Arterial adheres to the vessel wall - venous is loosely attached and friable
How does the wells score work?
Add up the points, if 1 or under then not likely of deep vein thrombosis, if 2 or above dvt is likely
What does it mean if d-dimer levels are increased?
D-dimer is the substance that breaks down clots so if it is increased it’s because there is a high quantity of clots that need to be broken down
What can cause a false positive of d-dimer test?
Liver disease, inflammation, malignancy, trauma, pregnancy, recent surgery, advanced cancer
What is a pulmonary embolism?
A blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream
What are the presenting symptoms of pulmonary embolus?
Dyspnoea (difficulty breathing)
Tachypnoea (rapid breathing)
Pleuritic chest pain (stabbing pain in chest)
Cough
Haemoptysis (coughing up blood)
Collapse
Sudden death
What does the plasma do?
Transports nutrients, hormones, metabolic waste
Regulates pH, body temperature, cell water content
Reservoir for substances such as water/electrolytes
What are the features of albumin?
Globular protein
Synthesised in the liver
19 day half life
What are the features of albumin?
Globular protein
Synthesised in the liver
19 day half life
