22. DVT Flashcards
Name risks for DVT (Pre-test probability (clinical suspicion)) (3)
- Virchow’s Triad
- Acquired
- Hereditary
Name Virchow’s Triad
- une lésion pariétale
- stase veineuse
- un facteur hémostasique d’hypercoagulabilité.
Name acquired risks for DVT (9)
- Prior thromboembolism
- Recent major surgery
- Trauma
- Immobilization
- Antiphospholipid antibodies
- Malignancy
- Pregnancy
- Oral contraceptives
- Myeloproliferative disorders
Name hereditary risks for DVT (4)
- Factor V Leiden
- Prothrombin gene mutations
- Protein S or C deficiency
- Antithrombin deficiency
Describe : Wells Score
+1 point for each of the following
* Paralysis, paresis or recent orthopedic casting of lower extremity
* Bedridden >3 days recently or major surgery within 4 weeks
* Localized tenderness of the deep veins
* Swelling of entire leg
* Calf swelling 3 cm greater than other leg (measured 10 cm below the tibial tuberosity)
* Pitting edema greater in the symptomatic leg
* Non-varicose collateral superficial veins
* Active cancer or cancer treated within 6 months
* Previously documented DVT
-2 points for alternative diagnosis at least as likely as DVT (Baker’s cyst, cellulitis, muscle damage, superficial vein thrombosis, post-thrombotic syndrome, inguinal lymphadenopathy, extrinsic venous compression)
Score <2 = 6% DVT, ≥2 = 28% DVT
Name risks of Upper extremity DVT (3)
- Cathéter veineux central
- recent pacemaker
- malignancy
Descrbe D-dimer use
DVT involve with veins ?
- 70 à 80 % des TVP touchent les veines proximales à l’échographie, le plus souvent la veine poplitée et la veine fémorale superficielle.
- 20 à 30 % des TVP sont isolé dans les veines du mollet : le tibial antérieur, péronier et veines tibiales postérieures
Patients with moderate-high suspicion of DVT (unless high risk of bleed) should start what?
anticoagulation before diagnosis
How long to use anticoagulate?
- Anticoagulate for initial 3 months
- consider indefinite in unprovoked and cancer (and low risk bleeding):
Name anticoagulation options (3)
-
LMWH or IV heparin (5000 units bolus then 20 units/kg/hr target aPTT 2-3x control aPTT) overlap with warfarin for minimum 5 days and INR >2 for minimum 2 days
__
DOAC - Apixaban 10mg PO BID x 1 week, then 5mg PO BID (can decrease to 2.5mg PO BID after 6 months)
- Rivaroxaban 15mg PO BID x 3 weeks then 20mg PO daily (can decrease to 10mg PO daily after 6 months)
- Note: Dabigatran and Edoxaban require 5-10 day initial treatment bridge with LMWH
__ - Subcutaneous LMWH (eg. Dalteparin 100 U/kg SC daily or Enoxaparin 1.5mg/kg SC daily) or IV heparin x 5-10 days, then dabigatran 150mg PO BID
- LMWH x 1 month then DOAC or warfarin
Consider Warfarin when? (6)
- in valvular A Fib
- CrCl<30
- Antiphospholipid syndrome
- Weight >120kg
- Gastric bypass
- Liver failure
LMWH preferred in what patients ?
- Cancer and in Pregnancy : advantages include fixed/simple-dosing and lower HIT
- There is some evidence that apixaban can be used as an alternative for patient with cancer who do not want injections (but avoid in upper GI malignancy due to increased rate of bleeding)
Only consider Aspirin in DVT tx when?
those who are adverse to long-term anticoagulation (32% reduction of recurrent VTE vs 82% when on oral anticoagulants)
Isolated distal DVT anticoagulation when?
- only if symptomatic and risk factors for extension (severe symptoms, >5cm in length, multiple deep veins, close to popliteal veins, no reversible risk factor, previous VTE, in-patient, positive D-dimer)
- progression on imaging
Urgent surgical intervention for what?
**phlegmasia cerulea dolens **(extensive thrombosis which can cause irreversible ischemia, necrosis, gangrene)
