Bleeding disorders Flashcards
Vascular abnormalities of platelet failure?
Hereditary
Acquire
- Vasculitis eg HSP
The 2 general causes of thrombocytopenia?
Reduced production
Increased destruction
Causes of peripheral platelet destruction?
Coagulopathy
Autoimmune
Hypersplenism
Causes of platelet functional defects?
Hereditary
Acquired
eg drugs (aspirin, NSAID) Renal failure
Features of VWF deficiency?
Autosomal dominant
Common
Variable severity
Causes of failure of fibrin clot?
Multiple clotting factor deficienies
Single clotting factor deficiency eg haemophilia
Examples of multiple factor deficiencies?
Liver failure
Vit K deficiency/Warfarin
Complex coagulopathy eg DIC
Where are coagulation factors synthesised?
In hepatocytes, hence reduced in liver failure
What does Vitamin K require to be absorbed, and where does this occur?
Requires bile salts to be absorbed, happens in upper intestine
Causes of Vit K deficiency?
Poor intake Malabsorption Obstructive jaundice Vit K antagonist eg warfarin Haemorrhagic disease of the newborn
What is DIC?
Excessive and inappropriate activation of haemostatic system
Causes microvascular thrombi–> end organ failure
Uses up clotting factors–> Bruising, purpura and generalised bleeding
Causes of DIC?
Sepsis
Obstetric emergencies
Malignancy
Hypovolaemic shock
Treatment of DIC?
Underlying cause Replacement rherapy (Platelets, plasma, fibrinogen)
What is haemophillia>
X linked disorder with episodic abnormally prolonged bleeding
A and B
Haemophilia A deficiency?
factor 8
