Y Lecture 1: Venous Thrombosis: aetiology and management Flashcards
What is the triad of symptoms in thrombophlebitic syndrome?
Recurrent pain
Swelling
Ulcers
What catalyses the conversion of fibrinogen to fibrin?
Thrombin
Which anticoagulant molecules are expressed on the blood vessel wall?
ThrombomodulinEndothelial Protein C receptorTFPI
How does inflammation affect the blood vessel wall?
It makes it prothrombotic
Recall 5 effects of inflammation on the blood vessel wall
- Anticoagulant molecules are downregulated2. TF expressed3. Prostacyclin decreased4. Adhesion molecules upregulated5. VWF released (leading to neutrophil capture, and formation of NETs)
How do neutrophils contribute to immunothrombosis?
Neutrophils release DNA, which is procoagulant
What is the mechanism of action of clopidogrel?
Inhibits ADP receptors
Give 4 ways in which blood stasis promotes thrombosis
- Accumulation of activated factors 2. Promotes platelet adhesion 3. Promotes leukocyte adhesion and transmigration 4. Hypoxia produces inflammatory effect on endothelium
What is the broad mechanism of action of heparins?
Potentiate antithrombin
What is one risk of long term heparin use?
Osteoporosis
Give an example of an anti-Xa drug
Rivaroxaban
Give an example of an anti-IIa drug
Dabigatran
How does warfarin affect vit K?
Prevents recycling of Vit K
Which procoagulant factors fall as a result of warfarin medication?
II, VII, IX and XAlso Protein C and Protein S
How is warfarin monitored?
INR measure
Why should warfarin never be given to pregnant women?
It is teratogenic
Give an example of an LMWH
Enoxaparin/ Tinzaparin
What scoring system is used to calculate risk of thrombosis?
Chads-vasc
Which surgeries carry the highest risk of thrombosis?
Orthopaedic
Which surgeries carry highest risk of bleeding?
Neuro, spinal or eye surgery
Which class of anti-coagulants carries a significantly lower risk of intracranial bleeding?
DOACs
What is the best drug to use as a long-term anticoagulant in a patient who has had an idiopathic VTE?
DOACs
Recall 3 minor precipitants of thrombosis
COPDflightstrauma
After someone has suffered a thrombosis due to a minor precipitant, how long should they be anti-coagulated for?
3 months
Recall the order in which the different coagulation factors in the intrinsic pathway catalyse each other?
12119810
Which coagulation measure is used to monitor heparin therapy?
APTT
Which coagulation measure is used to monitor warfarin therapy?
PT (INR)
Which factor does the extrinsic pathway start with?
Seven
