Pulmonary Embolism Severity Index (PESI)
Predicts 30-day mortality in acute pulmonary embolism. Guides decision between inpatient vs outpatient management.
How to use & interpret
The PESI (and simplified sPESI) estimates 30-day mortality after acute pulmonary embolism and is used to identify low-risk patients who may be suitable for outpatient or early-discharge management. PESI sorts patients into classes I–V; classes I–II (or an sPESI of 0) indicate low risk.
It supports — but does not replace — assessment of haemodynamic stability, right-heart strain (echo/CT, troponin, BNP) and social factors before deciding on ambulatory care.
Score interpretation
→ Outpatient treatment or early discharge; DOAC
→ Short inpatient stay or outpatient with close follow-up
→ Inpatient treatment; monitor closely
→ Inpatient; ICU consideration; assess for thrombolysis
→ ICU; consider systemic thrombolysis or catheter-directed therapy
Interpretation bands for the PESI. Apply clinical judgement and local guidance.
Frequently asked questions
Can a low PESI alone justify outpatient PE treatment?
No. Confirm haemodynamic stability, absence of right-ventricular dysfunction, adequate home circumstances and follow-up, and check for contraindications before ambulatory management.
References
Related
Curated clinical cross-links plus same-class fallbacks.
- Composite Pulmonary Embolism Shock (CPES) Score · Pulmonary Embolism
- YEARS Algorithm for Pulmonary Embolism · Pulmonary Embolism
- Wells' Criteria for Pulmonary Embolism · Pulmonary Embolism
- Revised Geneva Score for Pulmonary Embolism · Pulmonary Embolism
- Bova Score for Pulmonary Embolism Complications · Pulmonary Embolism
- Pulmonary Embolism Severity Index (PESI) -- Full Version · Pulmonary Embolism
- Nitric Oxide (Inhaled — iNO) · Selective Pulmonary Vasodilator
- Selexipag · Pulmonary Arterial Hypertension
- Macitentan · Pulmonary Arterial Hypertension
- Palivizumab · RSV Prophylaxis — Monthly Monoclonal Antibody (High-Risk Infants)
- Sildenafil (Paediatric — PPHN / PAH) · PDE5 Inhibitor (Paediatric Pulmonary Hypertension)
- Ziprasidone · Atypical Antipsychotic — D2/5-HT2A Antagonist (Low Metabolic Risk)
- Acute Asthma in Adults · BTS/SIGN British Guideline on Asthma 2019; NICE NG80
- Pulmonary Embolism Assessment · NICE NG158; ESC 2019 PE Guidelines
- Acute Exacerbation of COPD (AECOPD) · NICE NG115; GOLD 2024
- Spontaneous Pneumothorax (Adult) · BTS Pleural Disease 2023
- Atypical Pneumonia (Legionella / Mycoplasma / Chlamydophila) · BTS 2023; IDSA
- COPD Exacerbation Management · NICE NG115 / GOLD 2024
Featured in these MRCEM clinical pathways
The PESI is covered in detail — with RCEM/NICE evidence base, indications and pitfalls — in the following exam-focused pathways on our sister siteReviseMRCEM.
MRCEM Primary / Intermediate / OSCE candidates: each pathway includes exam-style questions, RCEM/NICE citations, and FAQ summaries.
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.