Venous Thromboembolism Flashcards
(19 cards)
What is a thrombus?
A solid mass in a blood vessel or the heart
Thrombosis is a pathological process involving platelets, fibrin clot, neutrophils/monocytes, and trapped red cells
What is the difference between a thrombus and an embolus?
A thrombus is a solid mass in a blood vessel, while an embolus is a free-floating mass that can travel in the bloodstream
An embolus is usually made up of a thrombus, but can also consist of fat, amniotic fluid, gas, or tumor emboli
What are the constituents of a thrombus?
- Platelets
- Fibrin clot
- Neutrophils/monocytes
- Trapped red cells
What is venous thrombosis typically associated with?
Stasis in the deep veins of the leg
Venous thrombosis usually involves a fibrin clot and cells and is treated mainly with anticoagulants
What initiates arterial thrombosis?
Damaged endothelium
This leads to platelet adhesion and recruitment of coagulation, treated mainly with anti-platelet drugs
What are some major risk factors for deep vein thrombosis (DVT)?
- Age
- Active cancer
- Antiphospholipid syndrome
- Prolonged immobility
- Major surgery
What is the Wells score used for?
Estimating the risk of deep venous thrombosis
A score above 2 indicates high probability of DVT
What symptoms are associated with deep vein thrombosis?
- Leg swelling - unilateral
- Pain
- Warmth
- Skin discoloration
What are the presentations of pulmonary embolus?
- Shortness of breath
- Chest pain – classically respiratory dependent
- Non-productive cough
- Haemoptysis
What treatment is primarily used for venous thromboembolism?
- Direct oral anticoagulants (DOACs)
- Low molecular weight heparin (LMWH)
- Warfarin
- Thrombolysis (fibrinolysis)
What is the role of neutrophils in DVT?
They may be major initiating cells for DVT through adhesion and activation of coagulation
Hypoxia and local inflammation increase selectin expression, leading to neutrophil adhesion
What is the significance of D-dimer in diagnosing DVT?
It indicates recent fibrin production
A positive D-dimer test may lead to further investigation if the clinical probability is low
What defines provoked thrombosis?
An identifiable risk event contributed to the thrombus
Examples include surgery, pregnancy, and major trauma
What are complications that can arise from venous thrombosis?
- Venous insufficiency
- Chronic pain
- Swelling
- Skin trophic changes
- Chronic ulceration risk
What is the difference between provoked and unprovoked thromboses?
Provoked thrombosis has an identifiable risk event, while unprovoked thrombosis occurs without a previous risk event.
What is a common characteristic of pulmonary embolisms?
They can cause sudden death or hemodynamic instability in massive cases
Submassive PE may show right ventricular dysfunction with normal arterial blood pressure
What is the significance of age as a risk factor for venous thrombosis?
Age increases procoagulant levels and contributes to a persistent hypercoagulable state.
What are the common symptoms of cerebral venous and sinus thrombosis?
- Headaches
- Seizures
- Cranial nerve palsies
- Visual disturbance
What is the main treatment approach for acute VTE?
Anticoagulation to prevent extension of thrombus
Direct oral anticoagulants are preferred due to lower risks of bleeding
