Bleeding Disorders Flashcards
What are the 4 parts of haemostasis?
Vasconstriction
Platelet adhesion
Stabilisation
Self limitation
What causes self limitation of clotting?
tPA - plasminogen -> plasmin
What are protein C and protein S?
anticoagulants
What are the investigations used to assess a Bleeding disorder?
FBC - platelets
Coag screen - INR
APTT
FVII levels, vWF activity
What pathways does INR measure?
extrinsic and intrinsic pahways
Which pathway does APTT measure?
intrinsic
What symptom with patients experience when their platelets drop below 50?
petaecia
What are the two reasons for thrombocytopaenia?
decreased production of platelets (leukaemias)
consumption of platelets
What is the most common immune mediated thrombocytopaenia
Thrombocytopaenic purpura
What is the patogenisis of thrombocytopaenic purpura?
Abs against platelets cause them to be removed by the spleen
What are the two syndrome which occur in Thrombocytopaenic purpura?
Acute and chronic
What are the features of acute thrombocytopaenic purpura?
Children after an infection will be symptomatic but will not usuallyneed treatment
What are the features of chronic thrombocytopaenic purpura?
Happens in middle aged women and requires steroids or splenectomy
What drugs can cause immune mediated thrombocytopenia? (3)
penicillin, heparin, blood transfusion
Which two conditions should be excluded before the diagnosis of Thrombocytopenic purpura is confirmed?
SLE and HIV
What are the inherited coagulopathies?
Haemophilia and vW disease
What can cause acquired coagulopathy?
liver disease, Vit K deficiency
What are the two most common haemophillias?
Haemopillia A
Haemophillia B
Which haemophillia is most common?
Haemophillia A
What would coagulation screen look like in haemophillia?
high APTT normal PT as there is no insult on the extrinsic pathway
Which factor is depleted in haemophillia A?
Factor VIII
How is Von Wilibrand disease inherited?
Autosomal Dominant
How will Von Willibrand disease look on coag screen?
may look normal, may have to do a specific test
What is the treatment of VonWillibrand disease?
Desmopressin
Which clotting factors are affected by Vit. K?
Factors II, VII, IX, X
What causes vit K def.?
malnutrition, malabsorbtion and warfarin
What causes Disseminated intravascular coagulation?
gram -ve sepsis
end stage maligancy
mismatched transfusions
Name three exogenous causes of thrombopillia
Pregnancy, immobility and OCP, surgery
What is the main inherited cause of thrombophillia?
Factor V leiden
How quickly does heparin work?
immediate
How should unfranctionated heparin be given?
IV
How should LMW heparin be given?
subcut
What anticoagulant should be used in a pregnant woman?
heparin NOT WARFARIN
How is heparin reversed?
Protamine
