VTE Flashcards
What is Venous Thromboembolism (VTE)?
Thrombus formation in a vein
What are the types of Venous Thromboembolism?
- Deep Vein thrombosis (DVT)
- Pulmonary embolism (PE) - complication of a DVT
Virchow’s Triad outline the risk fcators for thrombosis formation, what are the 3 factors?
- Hypercoagulability
- Stasis
- Endothelial injury
What are general risk factors for VTE?
- Age
- Obesity
- Family History (FHx)
- Pregnancy (especially puerperium - last 6-8 weeks)
- Immobility
- Hospitalisation
- Anaesthesia
- Central venous catheter (femoral - subclavian)
What are underlying conditions that increase the risk of VTE?
- Malignancy
- Heart Failure (HF)
- Haematological conditions (e.g. thrombophilia, antiphospholipids, Behcet’s, polycythaemia, sickle cell, hyperviscosity, homocystinuria)
Which medications are associated with increased VTE risk?
- Combined oral contraceptive pill (COCP - 3rd generation higher risk)
- Hormone Replacement Therapy (HRT)
- Raloxifene
- Tamoxifen
- Antipsychotics (especially olanzapine)
True or False: 40% of patients diagnosed with a PE have no risk factors.
True
What scoring system is used for assessing DVT likelihood?
Two-level CVT Wells score
What are the steps if DVT is likely (score 2+)?
- Ultrasound (within 4hrs)
- D-dimer test
- Immediate Prophylaxis LMWH
What are the steps if DVT is unlikely (score under 1)?
- D-dimer test, if + –> ultrasound within 4hrs
- If cannot be done in 4hrs, prescribe prophylaxis LMWH
What is the first-line treatment for DVT?
DOACs (Apixaban, Rivaroxaban)
What should be done if DOACs are contraindicated in DVT 1st line management?
- LMWH + dabigatran/edoxaban
- LMWH + vitamin K antagonist (VKA, warfarin)
What is the treatment for a DVT in patients with severe renal impairment (<15) or antiphospholipid syndrome?
LMWH + VKA
What is the length of anticoagulation for provoked (known cause) VTE?
3 months
What is the length of anticoagulation for unprovoked (unknown cause) VTE?
6 months (assess bleeding risk - HAS-BLED score)
What is the significance of VTE in hospital settings?
VTE can be common in hospital due to increased risk factors seen in inpatients
What are specific hospital-related risk factors for VTE in medical patients?
Reduced/anticipated significant mobility reduction for 3+ days
What are types of medical prophylaxis for VTE?
- Anti-embolism stockings
- Intermittent pneumatic compression device
What are types of drug prophylaxis for VTE?
- Fondaparinux sodium (SC injection)
- LMWH (e.g. enoxaparin)
- Unfractionated heparin (UFH) - used in chronic kidney disease
What should women do regarding COCP/HRT before surgery?
Stop taking COCP/HRT 4 weeks before surgery
What are post-surgery prophylaxis measures for VTE?
- Mobilise patient as soon as possible
- Keep patient hydrated
