Bokov Plamen, Peiffer Claudine, Gallego Jorge, Pautrat Jade, Matrot Boris, Delclaux Christophe
Service de Physiologie Pédiatrique -Centre du Sommeil-CRMR Hypoventilations Alvéolaires Rares, AP-HP, Hôpital Robert Debré, INSERM NeuroDiderot, Université de Paris, Paris, France.
Service de Physiologie Pédiatrique, Assistance Publique - Hôpitaux de Paris (AP-HP), Hôpital Robert Debré, Paris, France.
Front Physiol. 2023 Jul 4;14:1217391. doi: 10.3389/fphys.2023.1217391. eCollection 2023.
Whether dysfunctional breathing (DB) subtype classification is useful remains undetermined. The hyperventilation provocation test (HVPT) is used to diagnose DB. This test begins with a 3-min phase of hyperventilation during which fractional end-tidal CO (FETCO) decreases that could be an assessment of plant gain, which relies on CO stores. Our aim was to assess 1) whether the children suffering from different subtypes of DB exhibit decreased plant gain and 2) the relationships between HVPT characteristics and plant gain. We retrospectively selected 48 children (median age 13.5 years, 36 females, 12 males) who exhibited during a cardiopulmonary exercise test either alveolar hyperventilation (transcutaneous PCO < 30 mmHg, = 6) or inappropriate hyperventilation (increased VE'/V'CO slope) without hypocapnia ( = 18) or dyspnea without hyperventilation ( = 18) compared to children exhibiting physiological breathlessness (dyspnea for sports only, = 6). These children underwent tidal-breathing recording (ventilation and FETCO allowing the calculation of plant gain) and a HVPT. The plant gain was significantly higher in the physiological group as compared to the dyspnea without hyperventilation group, = 0.024 and hyperventilation without hypocapnia group, = 0.008 (trend for the hyperventilation with hypocapnia group, = 0.078). The slope of linear decrease in FETCO during hyperventilation was significantly more negative in physiological breathlessness group as compared to hyperventilation without hypocapnia group ( = 0.005) and dyspnea without hyperventilation group ( = 0.049). The children with DB, regardless of their subtype, deplete their CO stores (decreased plant gain), which may be due to intermittent alveolar hyperventilation, suggesting the futility of our subtype classification.
功能失调性呼吸（DB）的亚型分类是否有用尚未确定。过度通气激发试验（HVPT）用于诊断DB。该试验始于3分钟的过度通气阶段，在此期间，呼气末二氧化碳分数（FETCO）下降，这可能是对依赖于二氧化碳储备的肺增益的一种评估。我们的目的是评估：1）患有不同亚型DB的儿童是否表现出肺增益降低；2）HVPT特征与肺增益之间的关系。我们回顾性选择了48名儿童（中位年龄13.5岁，女性36名，男性12名），他们在心肺运动试验中表现出肺泡过度通气（经皮PCO＜30mmHg，n = 6）或无低碳酸血症的不适当过度通气（VE'/V'CO斜率增加，n = 18）或无过度通气的呼吸困难（n = 18），并与表现出生理性呼吸急促（仅运动时呼吸困难，n = 6）的儿童进行比较。这些儿童接受了潮气呼吸记录（通气和FETCO，用于计算肺增益）和HVPT。与无过度通气的呼吸困难组相比，生理组的肺增益显著更高，P = 0.024；与无低碳酸血症的过度通气组相比，P = 0.008（低碳酸血症性过度通气组有趋势，P = 0.078）。与无低碳酸血症的过度通气组相比，生理呼吸急促组在过度通气期间FETCO的线性下降斜率显著更负（P = 0.005），与无过度通气的呼吸困难组相比，P = 0.049。患有DB的儿童，无论其亚型如何，都会耗尽其二氧化碳储备（肺增益降低），这可能是由于间歇性肺泡过度通气所致，提示我们的亚型分类可能是无用的。
