II. How to Use
When to Use
The pediatric asthma score can be used in children aged 2-18 years with a history of a diagnosis of asthma presenting with an asthma exacerbation to guide next steps in inpatient medical management. The score can also be used to guide treatment in the emergency department setting. The PAS has not been validated in children with significant comorbidities (eg. sickle cell disease or cystic fibrosis) and should be used cautiously in those populations.
Pearls / Pitfalls
The PAS was derived from a cohort of patients who had already received oral or IV steroids within 30 minutes of treatment initiation. While the PAS can quantify the severity of an asthma exacerbation at a point in time, it cannot predict response to treatment, nor the need for inpatient admission.
The PAS may be more useful when used to track changes and compare serial reassessments in children as they receive asthma treatments. A single PAS may be less useful than a trend in scores over time.
The PAS has shown good inter-observer agreement among physicians, nurses, and respiratory therapists in an ED setting.
Remember to consider alternative diagnoses such as foreign body aspiration, anatomic anomalies (eg vascular rings/slings), or congestive heart failure, particularly in children who respond minimally to usual asthma care.
The PAS was derived from a clinical practice pathway developed at a single academic center for use in an inpatient setting and is not well validated in terms of outcomes such as mortality or likelihood of inpatient admission. The PAS continues to be used in research today to quantify asthma severity, but other scores exist and may be better validated (e.g. the Pediatric Respiratory Assessment Measure aka “PRAM”).
Why to Use
When used as part of a standardized treatment protocol, the PAS has been shown to decrease length of stay, reduce costs, and improve quality of care.
The PAS can be helpful in patients unwilling or unable to perform peak expiratory flow measurements, or where peak flow measurement is not feasible (eg. resource limited settings or the emergency department). Peak flow measurements are also highly technique dependent, and comparison of peak flow measurements to prior scores is important for proper interpretation.
III. Next Steps
Advice
Next treatment steps can be guided by the PAS score:
A PAS of 5-7 is considered “Mild” severity. One can consider de-escalation of current therapies, such as spacing of albuterol doses and interval assessments, or consideration or discharge.
A PAS of 8-11 is considered “Moderate” in severity. Continuation of current therapies is recommended. In the emergency department setting, consider including adjunctive therapies (magnesium, epinephrine).
A PAS of 12-15 represents a “Severe” presentation, and escalation of therapy is recommended. One may consider increasing the frequency of breathing treatments, addition of adjunct medications (ipratropium, terbutaline, magnesium, epinephrine), and/or transfer to an intensive care unit setting.
Management
The derivation study authors used a therapy-driven protocol derived from review of asthma practice patterns in the hospital, NHLBI (National Heart, Lung, and Blood Institute) guidelines, and a review of literature regarding inpatient management of status asthmaticus. The protocol was designed to use either the PAS or peak expiratory flow rate to measure response to treatment.
Critical Actions
Always assess airway, breathing, and circulation prior to calculating PAS. The PAS was not developed for use on unstable patients, and emergent intervention must not be withheld to determine the score.
Any patient being treated for asthma exacerbation should receive systemic steroids in addition to albuterol unless there is a contraindication.
Prior to discharge, every patient and their family should receive education on use of home inhalers and/or nebulizers, an asthma action plan, and scheduled follow-up with their primary care physician. Ensure the patient has adequate supply of home controller medications, peak flow meter, and spacer if applicable.
IV. Evidence
Evidence Appraisal
The goal of the derivation study was to develop and “evaluate the effect of an inpatient asthma clinical pathway on cost and quality of care for children with asthma.” The PAS was based on previous practice methods at the institution (Children’s Hospital of The King’s Daughters, Norfolk, Virginia), NHLBI guidelines, and a search of the literature at the time. Outcomes and costs of treatment of asthmatic children before and after implementation of the PAS and associated treatment guidelines were examined using a retrospective cohort.
149 children were treated according to the clinical pathway from Sept to Dec 1997. Thirty-four were randomly selected and matched based on demographics (age, race, gender, admission, time of year, and comorbidities) to a retrospective cohort control group of asthmatic children treated prior to the implementation of the PAS and treatment protocol.
When comparing the two groups, they found:
-
Length of stay was approximately 50% lower in the group that used the PAS and treatment pathway.
-
Cost was on average $1,200 lower in the group that used the PAS and pathway.
-
Children in the PAS and pathway group were more likely to receive asthma education, prescriptions for controller medications, and equipment (spacers and peak flow meters) prior to discharge
-
PAS patients were more likely to receive oral corticosteroids over IV corticosteroids.
-
PAS patients were more likely to have close follow-up arranged at discharge than control patients.
While the results were profound and statistically significant, the sample size in this study was small. Additionally, although the control and cohort groups had similar demographics, they may not reflect the general population of pediatric asthmatics. For example, the two groups compared in the study were both 76% male, 97% African-American, and mostly between the ages of 2 and 15.
In a review article on severe acute asthma exacerbations, Neivas and Anand cite the PAS as a reliable means of assessing asthma severity in the ICU setting.
Another more recent study showed modest but acceptable (k = 0.57) interrater reliability of PAS calculation between pediatric ED nurses and trained study personnel (including pediatric emergency medicine fellows and attendings as well as a research nurse) (Gardiner & Wilkinson). In this study initial PAS did not predict need for hospital admission.
While the aforementioned studies have shown decent performance of the PAS when integrated into a clinical practice pathway, it is important to note that the score was derived now long ago (2000) in a small study and has not been validated insofar as patient outcomes such as mortality or need for readmission are concerned. Illness severity scores for children with asthma exacerbations are lacking in general, however the PAS remains a regularly utilized tool in current research around pediatric asthma care, particularly in published care pathways and quality improvement initiatives (e.g. Ozkaynak et al., J Asthma, 2023, and Willis et al., Respir Care, 2022).
Other validated asthma scores exist for use in children, including the Pediatric Respiratory Assessment Measure (PRAM, Ducharme et al., J Pediatr, 2008), which has had more extensive validation research performed (See Gray et al., Arch Dis Child, 2025).
Formula
Facts & Figures
Literature
Original/Primary
https://www.ncbi.nlm.nih.gov/pubmed/10831004
Kelly CS, Andersen CL, Pestian JP. Improved outcomes for hospitalized asthmatic children using a clinical pathway. Ann Allergy Asthma Immunol. 2000;84(5):509–516.
Validation
https://www.ncbi.nlm.nih.gov/pubmed/17983880
NAEPP: Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma- Summary Report. (2007). [erratum appears in J Allergy Clin Immunol. 2008 Jun;121(6):1330]. Journal of Allergy & Clinical Immunology, 120(5 Suppl): S94-138.
Other References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3668947/
Nievas IFF, Anand KJS. Severe Acute Asthma Exacerbation in Children: A Stepwise Approach for Escalating Therapy in a Pediatric Intensive Care Unit.The Journal of Pediatric Pharmacology and Therapeutics : JPPT. 2013;18(2):88-104. doi:10.5863/1551-6776-18.2.88.
https://pubmed.ncbi.nlm.nih.gov/34693935/
Gardiner MA, Wilkinson MH. Interrater Reliability of the Pediatric Asthma Score. Pediatr Emerg Care. 2022;38(4):143-146. doi:10.1097/PEC.0000000000002556
Ozkaynak M, Amura CR, Sills MR, Topoz I. Effects of a QI intervention on pediatric asthma treatment using patient outcomes and workflow in an emergency department. J Asthma. 2023 Aug;60(8):1573-1583. doi: 10.1080/02770903.2022.2162412. Epub 2023 Feb 8. PMID: 36562525; PMCID: PMC10293015.
Willis LD, Danner NP, Lloyd TL, Carper NL, Berlinski A. Safe and Effective Use of Score-Based Continuous Albuterol Therapy in a Pathway for Treatment of Pediatric Asthma Exacerbation. Respir Care. 2022 Nov;67(11):1396-1404. doi: 10.4187/respcare.10083. Epub 2022 Aug 9. PMID: 35944965.
Ducharme FM, Chalut D, Plotnick L, Savdie C, Kudirka D, Zhang X, Meng L, McGillivray D. The Pediatric Respiratory Assessment Measure: a valid clinical score for assessing acute asthma severity from toddlers to teenagers. J Pediatr. 2008 Apr;152(4):476-80, 480.e1. doi: 10.1016/j.jpeds.2007.08.034. Epub 2007 Oct 31. PMID: 18346499.
Gray C, Collings M, Benito J, Velasco R, Lyttle MD, Roland D, Schuh S, Shihabuddin B, Kwok M, Mahajan P, Johnson M, Zorc J, Khanna K, Yock-Corrales A, Fernandes RM, Santhanam I, Cheema B, Ong GY, Jaiganesh T, Powell C, Dalziel S, Babl FE, Couper J, Craig S. Analysis of the asthma scores recommended in guidelines for children presenting to the emergency department: a Pediatric Emergency Research Networks study. Arch Dis Child. 2025 May 16;110(6):422-428. doi: 10.1136/archdischild-2024-327635. PMID: 40155002; PMCID: PMC12171506.