Pulmonary embolism: Wells score, CTPA findings and anticoagulation
RezzyPulmonary embolism (PE) is a classic "can't miss" diagnosis for the AKT. It's all about risk stratification, knowing when to pull the trigger on imaging, and starting the right anticoagulation.
Let's start with the Wells Score, which helps us decide if a PE is clinically likely or unlikely.
Wells Score for Pulmonary Embolism
The Wells score is the most commonly used clinical prediction rule. For the AKT, you should be familiar with the two-level version used to guide the next steps in management.
| Clinical Feature | Points |
|---|---|
| Clinical signs and symptoms of DVT (minimum of leg swelling and pain with palpation of the deep veins) | 3.0 |
| PE is #1 diagnosis OR as likely as any other diagnosis | 3.0 |
| Heart rate > 100 beats per minute | 1.5 |
| Immobilization (at least 3 days) or surgery in the previous 4 weeks | 1.5 |
| Previous objectively diagnosed PE or DVT | 1.5 |
| Hemoptysis | 1.0 |
| Malignancy (on treatment, treated in the last 6 months, or palliative) | 1.0 |
Interpretation (Two-level PE Wells Score):
- PE Likely (> 4 points): Arrange an immediate CT Pulmonary Angiogram (CTPA). If there's a delay, start interim anticoagulation.
- PE Unlikely (≤ 4 points): Arrange a D-dimer test. If positive, arrange a CTPA (and interim anticoagulation if the CTPA is delayed).
I'll put this into a clear table format for you to reference easily.
| Wells Score Result | Clinical Probability | Recommended Action |
|---|---|---|
| > 4 points | PE Likely | Immediate CTPA (Interim anticoagulation if delay) |
| ≤ 4 points | PE Unlikely | Perform D-dimer test |
| D-dimer Positive | - | Arrange CTPA (Interim anticoagulation if delay) |
| D-dimer Negative | - | PE unlikely; consider alternative diagnosis |
When we move to imaging, the CT Pulmonary Angiogram (CTPA) is the gold standard. The key finding you're looking for is a filling defect—this is where the contrast (which looks bright white) is blocked by a clot (which looks dark grey or black) within the pulmonary arteries.
Let me find a clear image of what that looks like for you.
Setting up chat...