1) In patients complaining of leg pain and/or swelling, evaluate the likelihood of deep venous thrombosis (DVT) as investigation and treatment should differ according to the risk.
- calf pain, lower extremity swelling (>3cm c/w unaffected side-10cm below tibial tuberosity, circumference)
- erythema, warmth, tenderness +homan’s sign (calf pain on dorsiflexion)
4 Utilize investigations for DVT allowing for their limitations (e.g., Ultrasound and D-dimer).
- Hx and PE focused on the components of the Wells score
- Low Wells % –> d-dimer
- Moderate Wells % –> d-dimer can be used, but most clinicians prefer US
- High Wells % –> proximal or whole leg US
- Pt with a negative proximal US – f/u proximal US after 5-7 days to r/o extension of a distal DVT
- Distal: confined to deep calf veins vs Proximal: popliteal, femoral, iliac veins
- Pathogenesis: Virchow triad – Endothelial damage, Stasis, hypercoagulability
2 In patients with high probability for thrombotic disease (e.g., extensive leg clot, suspected pulmonary embolism) start anticoagulant therapy if tests will be delayed.
5 In patients with established DVT use oral anticoagulation appropriately, (e.g., start promptly, watch for drug interactions, monitor lab values and adjust dose when appropriate, stop warfarin when appropriate,provide patient teaching).
7 Use compression stockings in appropriate patients, to prevent and treat post-phlebitic syndrome.
- Unless US is rapidly available, pt with moderate to high suspicion of DVT should start therapy before the dx is confirmed (unless they have a high risk of bleeding)
- Out-pt management is preferred
- Initial Tx should have an immediate anticoagulant effect – warfarin monotherapy is not appropriate initially
- Compression stockings (knee-high with min 30-40mmHg at the ankle x 1yr) in pt with symptoms of post-thrombotic syndrome
- chronic venous insufficiency 2o to DVT: pain, venous dilation, edema, pigmentation, skin changes, venous ulcers
- At risk: High BMI, female, advanced age
- LMWH may be used as initial therapy in conjunction with warfarin for the first 5 days and until (INR) reaches at least 2.0 (for min of 48hr), or may be used as monotherapy for the full duration of treatment.
- Dalteparin (Fragmin®): 200 U/kg SC daily or 100 U/kg SC twice daily (once daily dosing preferred).
- Enoxaparin (Lovenox®): 1 mg/kg SC twice daily or 1.5 mg/kg SC once daily.
- Tinzaparin (Innohep®): 175 U/kg once daily.
- Rivaroxaban (Xa inhibitor) is approved for Tx DVT without symptomatic pulmonary embolism.
- 15 mg bid x 21 days, followed by 20 mg daily for the duration of treatment.
- Rivaroxaban should not be used in women who are pregnant or breast-feeding.
- The Tx should continue for a min of 3mo, if recurrent, might continue Tx indefinetely
Upper Extremity DVT – rare
- Acute and chronic arm pain, swelling discoloration, and dilated collateral veins over the arm, neck, or chest
- Risk factors
- Central venous catheters
- pacemaker wires
- Thoracic outlet syndrome (Paget-schroetter syndrome)
- Pre-test probability scores not validated
Distal Lower Extremity DVT
- No Tx required unless progression to proximal DVT is likely
- If isolated distal DVT is found, anticoagulation may be offered if severe symptoms are present or if the risk of proximal extension is high.
- Pt may be followed with serial US for 2 weeks, after which time extension is unlikely.
- Risk factors for proximal extension:
- Positive D-dimer
- Extensive thrombosis
- distal DVT
- hx of VTE
- In-patient status
Wells Score for DVT
|Paralysis, paresis or recent orthopedic casting of lower extremity||1|
|Recently bedridden (> 3 days) or major surgery within past 4 weeks||1|
|Localized tenderness in the deep veins||1|
|Swelling of entire leg||1|
|Calf swelling 3 cm greater than other leg (measured 10 cm below the tibial tuberosity)||1|
|Pitting edema greater in the symptomatic leg||1|
|Collateral non-varicose superficial veins||1|
|Active cancer or cancer treated within 6 months||1|
|Alternative diagnosis more likely than DVT (Baker’s cyst, cellulitis, muscle damage, superficial venous thrombosis, post-phlebitic syndrome, inguinal lymphadenopathy, external venous compression)||-2|
|Wells Score||Probability of DVT||Strata|
|-2 – 0||5%||Low|
|1 – 2||17%||Moderate|
|3 – 8||53%||High|
3 Identify patients likely to benefit from DVT prophylaxis.
- Age >=60
- HRT – Estrogen therapy, oral corticosteroids
- Active Cancer
- 1o degree relative w/ DVT or previous DVT
- hematological disorders – known thrombophilia
- Surgery, fractures, trauma
- IBD, rheumatological dz or inflammatory condition, sepsis
- nephrotic syndrome, antiphospholipid syndrome
DVT Prophylaxis for Adult Patients with Moderate or High Risk of VTE:
Anyone fulfill Virchow’s triad
- significantly reduced mobility for 3 days or more
- Medical patients with ongoing reduced mobility (compared to their usual state) AND have one or more risk factors for VTE
- Surgical procedure with a total anesthetic and surgical time 60 minutes or longer
- Acute surgical admission with an inflammatory or intra-abdominal condition
- Surgical patients with one or more risk factors for VTE
- No Contraindication to anticoagulation:
- active bleeding,
- risk of bleeding to critical sites (intracranial, intraspinal, pericardial, introcular, retroperitoneal),
- untreated major bleeding disorder, acquired systemic coagulopathy
6 Consider the possibility of an underlying coagulopathy in patients with DVT, especially when unexpected.
- up to 40% of DVT patients have thrombophilias, especially unprovoked
- major ones are APC resistance, protein C or Protein S deficiency, APS, prothrombin gene mutation, Factor V leiden.
- suggested to Ix in young pt, + fmHx or recurrent DVT/PE pt