Haemostasis 2 Flashcards
What is the balance between coagulation and fibrinolysis when bleeding?
Coagulation factors decrease and platelets decrease
Fibrinolytic factors and anti coagulants increase
Why may coagulation factors be low?
failure of production: congenital and acquired
defective function of a specific factor:
genetic or acquired from drugs, synthetic defects, inhibition
How do platelets adhere to collagen?
Directly via GLpIa or GLpIb indirectly via VWF
What may be disorders of primary haemostsis?
Platelet disorders
What is thombocytopenia?
Low numbers of platelets
What may cause thombocytopenia?
Bone marrow failure due to Leukaemia or B12 defiency
Accelerated clearance e.g. immune, disseminated intravascular coagulation
Pooling and destruction in an enlarged spleen
What may cause an impared function of platelets?
Hereditary absence of glycoproteins or storage granules - this is rare
Acquired due to drugs
What impairment is found with Glenzmann’s thrombasthenia?
Absence of GpIIb/IIIa
What impairment is found with bernal soulier syndrome?
Absence of GpIb receptors
What impairments are found with storage pool disease?
reduction of dense granules in platelet e/g/
ADP
ATP
Which drugs can cause impaired platelet function?
Aspirin
NSAIDs
Clopidogrel (common)
