An a Priori Approach to Small Airway Dysfunction in Pediatric Asthmatics

Small airway dysfunction remains a stepchild in the pediatric asthma care pathway. In brief, elements of the pulmonary function test (PFT) concerning smaller airway data remain less utilized. To further the value of the standard PFT we underwent a prospective Proof of Concept (POC) project, utilizing the outpatient performance of PFT tests in children 6-18 years during a 15-month period. The goal of the study was to determine if a priori the PFT represented a small airway disease pattern or not. Only the pulmonary function was used to make that distinction. Children 6-18 years with asthma who completed a PFT had their PFT as being characterized with or without a small airway dysfunction (SAD) designation, coded in the electronic medical record as an a priori decision using the code J98.4 (other disorders of lung) as a marker for electronic medical records retrieval. Subsequently, the results were analyzed between a group of 136 children designated (a priori) as having no small airway dysfunction in comparison to 91 children a priori designated as having small airway dysfunction. The a priori designation groups were post hoc compared for large and smaller airway function differences. Both large and smaller airway dysfunction were highly significantly different between the 2 groups, based solely on the initial division of the total group based on the decision the PFT represented a small airway pattern. We concluded the baseline pulmonary function test used in the evaluation of pediatric asthma has readily identifiable information regarding the presence of small airway dysfunction, and we characterized what was unique on the PFT based on that SAD classification.