Karila C, Saulnier J-P, Elie C, Taupin P, Scheinmann P, Le Bourgeois M, Waernessycle S, de Blic J
Service de Pneumologie et allergologie pédiatriques, Hôpital Necker-Enfants malades, Paris, France.
Rev Mal Respir. 2008 Mar;25(3):303-12. doi: 10.1016/s0761-8425(08)71549-3.
We aimed to confirm that children who have survived bronchopulmonary dysplasia (BPD) display lower ventilation during exercise than healthy children, and to determine whether alveolar hypoventilation associated with exercise-induced hypoxemia occurred in these children.
Twenty children with BPD (birth weight 1441+/-523 g [mean +/- SD], gestational age 31+2.3 weeks), aged 7 to 14 years, and 18 matched healthy children, born at term, performed resting pulmonary function and cardiopulmonary incremental exercise tests. Arterialized capillary blood gases were measured at rest and at maximal exercise in the BPD group.
The BPD group showed moderate expiratory airflow limitation and hyperinflation. Maximal oxygen uptake and ventilatory threshold were similar in the two groups. The BPD group displayed ventilatory limitation on exercise, with greater use of the ventilatory reserve (p<0.01), lower maximal ventilation (p<0.01), tidal volume (p=0.01). Changes in ventilation (p<0.0001) and tidal volume (p=0.003) during exercise were significantly smaller in the BPD group than in controls, at similar submaximal workloads. At peak exercise, we observed hypoxemia in 12 BPD children (60%). In the subgroup with hypoxemia, a significant increase in PaCO2 (p=0.01) was measured at peak exercise, showing alveolar hypoventilation sustained by the lower tidal volume.
Despite normal maximal aerobic performance, BPD children showed ventilatory limitation on exercise, frequently with hypoxemia and alveolar hypoventilation. Despite an improvement in their pulmonary condition, continued follow-up by cardiopulmonary exercise testing, is strongly recommended.
我们旨在证实支气管肺发育不良（BPD）存活儿童在运动时的通气量低于健康儿童，并确定这些儿童是否存在与运动性低氧血症相关的肺泡低通气。
20名BPD儿童（出生体重1441±523g[均值±标准差]，胎龄31+2.3周），年龄7至14岁，以及18名匹配的足月出生的健康儿童，进行了静息肺功能和心肺递增运动试验。对BPD组在静息和最大运动时测量动脉化毛细血管血气。
BPD组表现出中度呼气气流受限和肺过度充气。两组的最大摄氧量和通气阈值相似。BPD组在运动时表现出通气受限，通气储备的使用率更高（p<0.01），最大通气量更低（p<0.01），潮气量更低（p=0.01）。在相似的次最大工作量下，BPD组运动期间的通气量变化（p<0.0001）和潮气量变化（p=0.003）明显小于对照组。在运动峰值时，我们观察到12名BPD儿童（60%）出现低氧血症。在低氧血症亚组中，运动峰值时测得PaCO2显著升高（p=0.01），表明较低潮气量维持了肺泡低通气。
尽管最大有氧能力正常，但BPD儿童在运动时表现出通气受限，常伴有低氧血症和肺泡低通气。尽管他们的肺部状况有所改善，但强烈建议通过心肺运动试验进行持续随访。
