Venous thromboembolic diseases Flashcards
What are provoked and unprovoked DVTs?
- Provoked DVT: associated with a transient risk factor, which can be removed to reduce risk of recurrence.
- Unprovoked DVT: absence of a transient risk factor, person is at increased risk of recurrence.
Name four continuous or intrinsic risk factors for DVT
- Previous DVT
- Cancer
- Age over 60
- Overweight; obesity
- Male
- Heart failure
- Acquired/familial thrombophilia
- Inflammatory disorders: eg. vasculitis; IBD
- Varicose veins
- Smoking
Name four transient risk factors for DVT
- Recent major surgery; hospitilisation; trauma
- Chemotherapy
- Significant immobility
- Prolonged travel (>4h)
- Significant trauma; direct trauma to vein
- COCP; HRT
- Pregnancy; postpartum period
- Dehydration
Name two complications of deep venous thrombosis
- Pulmonary embolism
- Post-thrombotic syndrome
- Bleeding associated with anticoagulation treatment
- Heparin-induced thrombocytopenia
What is post-thrombotic syndrome?
DVT complication affecting up to 50% (within two years)
- Chronic venous HTN, causing:
- Limb pain; swelling
- Hyperpigmentation; dermatitis
- Ulcers
- Venous gangrene
- Lipodermatosclerosis
Name three differential diagnoses for DVT
- Physical trauma
- Cardiovascular disorders:
- Superficial thrombophlebitis
- Post-thrombotic syndrome
- Venous obstruction; insufficiency
- Ruptured baker’s cyst
- Cellulitis
- Dependent oedema
- Nephrotic syndrome; cirrhosis
- Compartment syndrome
List four presenting features of a DVT
- Unilateral swollen leg (esp >3cm difference)
- Localised pain: typically throbbing
- Tender
- Oedematous; erythematous; warm
- Vein distension
What scoring system is used to assess DVT risk?
Two-level DVT Wells score
Outline the initial investigation of patients with likely DVT (2+ Wells score)
-
Proximal leg vein USS within 4h
- D-dimer if scan result is negative
- Repeat scan if D-dimer positive
- If unable to obtain scan within 4h:
- D-dimer test
- Interim 24h treatment-dose LMWH
- Proximal leg USS within 24h
Outline the initial investigation of patients with unlikely DVT (<2 Wells score)?
D-dimer test:
- If +ve: proximal leg vein USS within 4h
- If -ve: consider alternative diagnosis
What investigations should be offered in unprovoked DVT?
- Investigations for possible malignancy
- CT abdomen and pelvis
- Thrombophilia testing
Give three ECG findings in pulmonary embolism
- Sinus tachycardia
- RV strain: T wave inversion in V1-4
- RBBB
- Dominant R wave in V1
-
S1Q3T3: non-specific
- -S wave in lead I
- -Q wave in lead III
- -T wave inversion in lead III
What scoring system is used to assess PE risk?
PE Wells score - original or simplified
Outline the initial investigation of patients with likely PE (>4 Wells score)
- CTPA immediately
- V/Q SPECT scan if:
- Allergy to contrast media
- Severe renal impairment (eGFR <30ml/min)
- High risk from irradiation
- If either is delayed, offer interim anticoagulation
- eg. apixaban; rivaroxaban
Outline the initial investigation of patients with unlikely PE (4 or less Wells score)
D-dimer test, results within 4h
- If +ve: investigate as likely PE
- CTPA or V/Q SPECT scan, ± interim anticoagulation
- If -ve: consider alternative Dx