Bleeding Disorders Flashcards
What are the 4 components of haemostasis?
Formation of the platelet plug
Formation of the fibrin clot
Fibrinolysis
Anticoagulant defences
Is thrombocytopenia usually hereditary or acquired?
Acquired
What pattern of inheritance is seen in VWF deficiency disorders?
Autosomal dominant
Has variable severity.
What is the most common cause of primary haemostatic failure?
Thrombocytopenia
What are the most common causes of thrombocytopenia?
Primary haemostatic failure
What clotting factors are produced by vitamin K?
II, VII, IX and X.
What occurs in disseminated intravascular coagulation (DIC)?
Massive activation of haemostasis due to tissue injury. It is to such an extent that clotting factors are used up.
What causes haemophilia A?
Clotting factor 8 deficiency
What causes haemophilia B?
Clotting factor 9 deficiency
What causes single clotting factor deficiencies?
Genetic conditions - these are called haemophilia.
What causes multiple blood clotting factor deficicencies?
Liver failure
Vitamin K deficiency/Warfarin overdose
How is warfarin overdose treated?
Vitamin K
How does DIC affect PT and APTT?
They are both prolonged.
How is vitamin K attained through diet?
Leafy green vegetables.
Why does obstructive jaundice cause vitamin K deficiency?
As bile salts are needed for absorption.
What is haemorrhagic disease of the newborn?
Vitamin K deficiency due to a lack of dietary supplementation and a lack of bowel bacteria.
Disseminated intravascular coagulation can be due to what?
Sepsis
Obstetric emergency
Malignancy
Hypovolaemic shock
How is DIC treated?
By managing the underlying cause.
It is a rapidly progressive state.
What pattern of inheritance is seen in haemophilia?
X-linked.
These means males are more likely to be affected.
What form of haemophilia is more common?
Haemophilia A
How does severe haemophilia present?
Recurrent haemarthrosis (recurrent bleeding into joints) Recurrent soft tissue bleeds Prolonged bleeding following procedures
How does haemophilia affect APTT and PT?
Prolonged APTT (as this measures factor VIII and IX) Normal PT
Do patients with haemophilia have ‘target joints’?
Yes, these are joints which are more likely to develop within.
Can cause joint fusing.
