RT Journal Article SR Electronic T1 Children with bronchopulmonary dysplasia (BPD) have increased dynamic flow limitation and an altered ventilatory response to exercise JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p1545 VO 38 IS Suppl 55 A1 Christopher O'Dea A1 Karla Logie A1 Andrew Wilson A1 Andrew Maiorana A1 Jane Pillow A1 Graham Hall YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p1545.abstract AB Introduction: Children born preterm are known to have altered lung structure and function. These changes may lead to dynamic flow limitation (DFL) during exercise. This study aimed to determine the prevalence of DFL and the ventilatory response to exercise in preterm children aged 9-11yrs with and without BPD.Methods: Preterm children (<32 w gestation) with and without BPD (>28 d supplemental O2 at 36 w post menstrual age) and term born healthy controls performed an incremental treadmill exercise test to volitional exhaustion with breath by breath analysis and exercise tidal flow volume loops.Results: To date 89 children (33 BPD, 25 nonBPD and 31 controls) performed acceptable exercise tests. Children with BPD were more likely to have DFL (n=15, 36%) compared to nonBPD (n=3, 11%) and term controls (n=2, 6.3%) p<0.05. The pre-term children had a significantly lower peak V'O2 than the term born controls (43.8 vs. 49.8. mL/kg/min, p<0.001). Children with BPD had a reduced O2 pulse (p<0.001), tidal volume and V'E (p<0.001) compared to nonBPD and term controls. Preterm children with dynamic flow limitation had lower FEV1 z-scores compared to those without (p<0.02) with other ventilatory responses to exercise not altered in the presence of DFL.Conclusion: Children born preterm have a lower aerobic exercise capacity and those with BPD exhibit both cardiac and respiratory limitation to exercise. The presence of DFL in children born pre-term with BPD is a novel finding and further research on its potential impact is required.