P90 Impulse oscillometry in preschool children-types of airway defects

Abstract

<h3>Introduction</h3> Many tests commonly used in school going children are now gaining prominence in children less than five years of age. One recent study indicated that impulse oscillometry (IOS) reliably measures distal airway function in preschool children. IOS values during preschool years correlate well with lung function in adolescence by spirometry. We aimed to assess the different types of airway defects IOS can pick up in children less than 5 years of age. <h3>Methods</h3> Children aged 3–5 years with CF, PCD and preschool wheeze referred for assessment of lung function from outpatient clinics were included in this study. Jaeger MS-IOS Digital Viasys was used for IOS. It was calibrated using a 3L syringe before measurements. Children were asked to breathe tidally for 30 seconds for IOS manoeuvre. Recommended coherence values (r2 &gt; 0.6 at 5 Hz and r2 &gt; 0.9 at 20 Hz) were used to ensure adequate technique. A variability of 10% in values for two out of three attempts was deemed acceptable. <h3>Results</h3> This study was conducted over four months. Thirty-two children were included in the study. Median age was 5 years. Mean height was 114.5 cm (SD ±10.1). The study sample consisted of 14 males and 18 females. 17(53%) children included in the study were clinically diagnosed to have preschool wheeze or probable asthma. There were 11(34%) children with CF and 4(13%) with PCD. Pearson coefficient(r) for BDR(R5) and BDR(R5-R20) in distal obstruction or small airway disease was 0.73(p=0.003). We also analysed association of AX with R5 BDR (r=0.21,p=0.001) and R5-R20 BDR (r=0.35, p=0.0007) for children with distal airway obstruction. <h3>Conclusion</h3> IOS has an important place in lung function in preschool children as it is an effort independent test and requires passive cooperation only. Evidence suggests that it can detect small airway disease earlier than spirometry. <h3>Reference</h3> Lauhkonen E, Riikonen R, Törmänen S, Koponen P, Nuolivirta K, Helminen M, Toikka J, Korppi M. Impulse oscillometry at preschool age is a strong predictor of lung function by flow-volume spirometry in adolescence. <i>Pediatr Pulmonol</i> 2018;<b>53</b>(5):552–558.