A decrease in plant gain, namely CO2 stores, characterizes dysfunctional breathing whatever its subtype in children

Background: Whether dysfunctional breathing (DB) subtype classification is useful remains undetermined. The hyperventilation provocation test (HVPT) used to diagnose DB. This begins with a 3-min phase of during which fractional end-tidal CO 2 (FETCO ) decreases that could be an assessment plant gain, relies on stores. Our aim was assess 1) whether the children suffering from different subtypes DB exhibit decreased gain and 2) relationships between HVPT characteristics gain. Methods: We retrospectively selected 48 (median age 13.5 years, 36 females, 12 males) who exhibited cardiopulmonary exercise either alveolar (transcutaneous PCO < 30 mmHg, n = 6) or inappropriate (increased VE’/V’CO slope) without hypocapnia ( 18) dyspnea compared exhibiting physiological breathlessness (dyspnea for sports only, 6). These underwent tidal-breathing recording (ventilation FETCO allowing calculation gain) HVPT. Results: significantly higher in group as group, p 0.024 0.008 (trend 0.078). slope linear decrease more negative 0.005) 0.049). Conclusion: DB, regardless their subtype, deplete stores (decreased gain), may due intermittent hyperventilation, suggesting futility our classification.