What it is
The Pediatric Asthma Severity Score (PASS) is a three-item clinical score for grading the severity of an acute asthma exacerbation in children. Derived by Gorelick and colleagues in 2004, it was built to be fast, reproducible, and require no investigations — just inspection and auscultation at the bedside. It discriminated well between children who did and did not need admission (area under the ROC curve ~0.82) and was responsive to treatment.
The components
Three findings, each scored 0–2:
| Item | 0 | 1 | 2 |
|---|---|---|---|
| Wheezing | None/mild | Moderate | Severe — or absent with poor air movement |
| Work of breathing | Normal/mild | Moderate | Severe |
| Prolonged expiration | Normal/mild | Moderate | Severe |
Total range 0–6. Note the trap built into the wheezing item: a silent chest from minimal air movement scores the maximum, not zero — absence of wheeze in a tiring child is ominous, not reassuring.
When to use it
Use it at triage and after each treatment cycle in a child (roughly 1–18 years) with a known or suspected acute asthma exacerbation. Its main job is to track trajectory and support the admit-versus-discharge decision, not to make it alone. Because it needs nothing beyond a stethoscope and inspection, it suits high-throughput emergency settings and serial reassessment, and it travels well between examiners — its inter-rater reliability was a design goal, so a score handed off at shift change carries meaning.
Worked example
A child with moderate wheeze (1), moderate work of breathing (1), and normal expiratory phase (0) scores 2 — toward the milder end. Treat with a bronchodilator, reassess, and watch whether the score falls. A relative fall in score after treatment is the signal the original study emphasised.
Pitfalls and caveats
- The mild/moderate/severe bands shown in the runner are an institutional interpretation, not from the source paper. Gorelick validated PASS for discrimination and responsiveness, not for fixed disposition cutoffs. Higher = worse; map to your local pathway.
- A silent chest is a high score, not a low one — do not let a quiet auscultation falsely reassure.
- It is one input among many. SpO₂, response to initial bronchodilator, prior ICU/intubation history, and overall gestalt all matter for disposition.
- Other validated scores (PRAM, modified pulmonary index) may be preferred in your unit; pick one and use it consistently.
Run it: Pediatric Asthma Severity Score (PASS)
Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.