Wells Criteria for Suspected DVT
Note: This tool is for teaching and bedside support only. Always use your clinical
judgement and follow your hospital / national DVT protocols. Discuss uncertain cases with a senior.
Interactive Wells Score Checklist
| Include? | Criterion | Points |
|---|---|---|
| Active cancer (treatment within last 6 months or palliative) | +1 | |
| Paralysis, paresis, or recent plaster immobilisation of the lower extremities | +1 | |
| Recently bedridden for ≥3 days, or major surgery within the past 12 weeks requiring general or regional anaesthesia | +1 | |
| Localised tenderness along the distribution of the deep venous system | +1 | |
| Entire leg swollen | +1 | |
| Calf swelling ≥3 cm larger than asymptomatic side (measured 10 cm below tibial tuberosity) | +1 | |
| Pitting oedema confined to the symptomatic leg | +1 | |
| Collateral superficial veins (non-varicose) | +1 | |
| An alternative diagnosis is at least as likely as DVT | −2 |
Interpretation of Wells Score
- Low risk: score ≤ 0
- Moderate risk: score 1–2
- High risk: score ≥ 3
Suggested ED Approach (Framework)
- Calculate Wells score and place the patient into low / moderate / high risk.
-
Low risk (≤ 0):
Consider D-dimer if available and appropriate:
- Negative D-dimer → DVT unlikely (consider alternatives).
- Positive D-dimer → arrange compression ultrasound.
-
Moderate or high risk (≥ 1):
- Arrange urgent compression ultrasound of the affected limb.
- Consider starting empiric anticoagulation if imaging is delayed and bleeding risk is acceptable.
-
If DVT is confirmed:
- Start anticoagulation as per local protocol (e.g. LMWH, DOAC, or warfarin-based regimen).
- Assess renal function, pregnancy status, bleeding risk, and drug interactions.
-
Symptom control & follow-up:
- Analgesia as needed.
- Consider compression stockings to reduce risk of post-thrombotic syndrome (once acute pain/swelling settles).
- Arrange outpatient follow-up (e.g. medical clinic / anticoagulation clinic).
- Look for underlying causes: recent surgery/immobilisation, malignancy, pregnancy, OCP/HRT, thrombophilia, previous VTE, long-haul travel, nephrotic syndrome, etc.
Red flags:
- Shortness of breath, pleuritic chest pain, hypoxia, syncope → suspect PE and escalate urgently.
- Massive limb swelling, phlegmasia, severe pain → discuss urgently with senior / vascular surgery.
- Major bleeding risk or haemodynamic instability → urgent senior input before anticoagulation.