Why grade a pulmonary embolism?
A pulmonary embolism (PE) is a blood clot that blocks an artery in the lungs. Its severity ranges from small clots that can be treated at home with blood thinners to massive clots that strain the heart and threaten life. Once PE is diagnosed, clinicians grade its severity to decide where and how to treat it. The simplified Pulmonary Embolism Severity Index (sPESI), published by David Jiménez and colleagues in 2010, is the quickest validated tool.
The six items
| Item | Points |
|---|---|
| Age over 80 | 1 |
| Cancer, active or treated in the past year | 1 |
| Chronic heart failure or chronic lung disease | 1 |
| Heart rate of 110/min or more | 1 |
| Systolic blood pressure below 100 mmHg | 1 |
| Oxygen saturation below 90% | 1 |
Interpretation
| sPESI | Risk | 30-day mortality in the derivation study |
|---|---|---|
| 0 | Low | about 1.0% |
| 1 or more | Not low | about 10.9% |
Worked example
A 68-year-old with a confirmed PE has a heart rate of 112, blood pressure 118 and saturation 93%, with no cancer or chronic heart or lung disease. Only the heart rate scores, for an sPESI of 1: not low risk. The next step is to look for right ventricular strain with an echocardiogram or CT and to measure troponin.
How guidelines use it
The European Society of Cardiology classifies PE into:
- High risk: shock or persistent low blood pressure; reperfusion treatment such as thrombolysis is considered.
- Intermediate risk: sPESI of 1 or more, or signs of right heart strain; hospital treatment, with closer monitoring if both imaging and troponin are abnormal.
- Low risk: sPESI of 0 and no right heart strain; early discharge and home treatment with a direct oral anticoagulant can be considered, provided there is good support at home.
sPESI versus PESI
The original PESI has 11 weighted items and five classes. The simplified version performs almost as well and is far easier to use at the bedside. Some centers use the Hestia criteria, a checklist of clinical and social reasons for admission, as an alternative.
Limits
sPESI is used only after PE is confirmed; it says nothing about whether PE is present. Decisions about home treatment also depend on bleeding risk, kidney function, social situation and the patient’s preference.
This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.