Related Subjects:
| Assessing Breathlessness
| Respiratory Failure
| Pulmonary Embolism
| Deep Vein Thrombosis
| DVT/PE in Pregnancy
| CTPA
Initial DVT Management Summary
Initial DVT Management Summary |
- Clinical assessment: If DVT is suspected, use the Wells score:
- Wells Score ≤ 0: Low/Unlikely Risk Group, DVT Prevalence 5%
- Wells Score 1-2: Moderate Risk Group, DVT Prevalence 17%
- Wells Score ≥ 3: High/Likely Risk Group, DVT Prevalence 17-53%
- Actions:
- If Wells Score 0-1: Check D-dimer
- If negative, DVT diagnosis is excluded; seek an alternative cause.
- If positive, arrange ultrasonography; treat if positive.
- If Wells Score ≥ 2: Do not check D-dimer; arrange ultrasonography. If negative, repeat ultrasound in one week.
|
About DVT
- Most pulmonary emboli (PE) originate as DVTs in the pelvic or leg veins.
- Failure to treat DVT can lead to PE and post-thrombotic syndrome.
- Prevention strategies in hospital settings include early mobilization, low molecular weight heparin (LMWH), and TED stockings.
Risk Factors
- General immobility (e.g., illness, stroke, neurological disorders)
- Post-operative state, malignancy
- Pelvic, orthopedic, or gynecological surgery
- Pregnancy, postpartum, and combined oral contraceptive pills (COCP)
- Inherited thrombophilia (Factor V Leiden, Protein C or S deficiency)
- Age >60 years, smoking, obesity
- Recent travel >4 hours within the past 2 weeks
- Congestive heart failure, hyperosmolar non-ketotic coma (HONK)
Risks Associated with COCP
- No combined pill: 5 DVT/PE per 100,000
- Second-generation combined pill: 15 DVT/PE per 100,000
- Third-generation combined pill: 25 DVT/PE per 100,000
- Pregnancy: 60 DVT/PE per 100,000
Clinical Presentation
- Calf pain, dilated veins, and erythema
- Homan’s sign – pain on dorsiflexion of the foot
- Positive tibial tap, obvious swelling
- Increase in calf circumference compared to the other leg
Investigations
- D-dimer test (only if low suspicion of DVT)
- Compression ultrasound (useful for proximal DVT, but may miss below-knee DVT)
- Venography (rarely performed now, but considered the gold standard)
- MRI (used in select cases but expensive)
- Thrombophilia screening in selected cases
Differential Diagnoses
- Venous thrombosis
- Calf haematoma
- Ruptured Baker’s cyst
- Cellulitis or soft tissue infection
- Lymphatic obstruction
- Congestive heart failure (CCF)/cor pulmonale
- Rupture of the gastrocnemius muscle
- Low albumin
Wells Score for DVT
- Paralysis, paresis, or recent orthopedic casting of the lower extremity (1 point)
- Recently bedridden (more than 3 days) or major surgery within the past 4 weeks (1 point)
- Localized tenderness along the deep vein system (1 point)
- Swelling of the entire leg (1 point)
- Calf swelling greater than 3 cm compared to the other leg (measured 10 cm below the tibial tuberosity) (1 point)
- Pitting edema greater in the symptomatic leg (1 point)
- Collateral non-varicose superficial veins (1 point)
- Active cancer (treatment within 6 months) (1 point)
- Alternative diagnosis more likely than DVT (e.g., Baker's cyst, cellulitis) (-2 points)
Wells Score Interpretation
- 3-8 Points: High probability of DVT
- 1-2 Points: Moderate probability
- -2-0 Points: Low probability
No decision rule should override clinical judgment. A high suspicion for DVT should prompt imaging, regardless of the Wells score.
Management
- Most ambulatory patients with DVT can be managed as outpatients.
- Start weight-adjusted LMWH (e.g., Enoxaparin 1 mg/kg twice daily) for 5 days if DVT is suspected.
- Once DVT is confirmed by imaging, start Warfarin (3-5 mg daily) along with LMWH until therapeutic INR is reached.
- Streptokinase may be used for large proximal DVTs.
- Below-knee DVT: 6 weeks of Warfarin.
- DVT or PE with no obvious cause: 6-12 months of Warfarin.
- DVT with a one-off cause: 3 months of Warfarin.
- Recurrent DVT/PE may warrant lifelong Warfarin.
- Consider thrombolysis for massive iliofemoral DVT with limb-threatening gangrene risk.
References
- Wells PS, Anderson DR, Bormanis J, et al. Value of assessment of pretest probability of deep-vein thrombosis in clinical management. Lancet. 1997;350(9094):1795-8.