Gozal D, Marcus C L, Ward S L, Keens T G
Division of Neonatology and Pediatric Pulmonology, Childrens Hospital Los Angeles, California, USA.
Am J Respir Crit Care Med. 1996 Feb;153(2):761-8. doi: 10.1164/ajrccm.153.2.8564130.
During exercise, children with congenital central hypoventilation syndrome (CCHS) demonstrate coupling of VE to exercise load, despite the absence of a VE response to changes in FICO2. To assess the effect of movement on VE, we studied six CCHS patients and six matched controls during passive motion in a motor-driven ergocycle at pedaling frequencies (PF) of 6 to 60 rpm. VE, VO2, VCO2, VT, heart rate, respiratory rate, SPO2, and PETCO2 were measured. During steady-state conditions, VE was constant at PF of 0 to 30 rpm, but increased at PF > or = 40 rpm in both controls and CCHS patients (p < 0.005). The increase in respiratory rate in CCHS patients was greater than in controls (p < 0.05) whereas VT increased similarly in both groups. At 60 rpm, VO2 increased in both groups, but VE/VO2 and VE/VCO2 increased in the CCHS patients and remained constant in the controls (P < 0.03; p < 0.04). From PF of 0 to 60, PETCO2 decreased from 47 +/- 7 to 41 +/- 6 mm Hg in the CCHS patients (p < 0.001) but remained unchanged in the controls (38 +/- 3 mm Hg; p = NS). An analysis of on-transient responses at 60 rpm revealed that VE increased immediately with the first breath after onset of motion in both groups, and that comparable differences in ventilatory patterns persisted in the two groups. We conclude that passive leg motion at PF > or = 40 increases VE in both CCHS patients and controls. In controls, VE was tightly coupled to VO2 and VCO2. However, in CCHS patients, passive leg motion elicited normalization of PETCO2.
在运动过程中，先天性中枢性低通气综合征（CCHS）患儿尽管对FICO2变化缺乏通气反应（VE），但其VE与运动负荷仍表现出耦合关系。为评估运动对VE的影响，我们在电动测力计上对6例CCHS患者和6例匹配的对照组进行了被动运动研究，踏频（PF）为6至60转/分钟。测量了VE、VO2、VCO2、VT、心率、呼吸频率、SPO2和PETCO2。在稳态条件下，对照组和CCHS患者在PF为0至30转/分钟时VE保持恒定，但在PF≥40转/分钟时增加（p<0.005）。CCHS患者呼吸频率的增加大于对照组（p<0.05），而两组VT的增加相似。在60转/分钟时，两组VO2均增加，但CCHS患者的VE/VO2和VE/VCO2增加，而对照组保持恒定（P<0.03；p<0.04）。从PF为0至60，CCHS患者的PETCO2从47±7降至41±6毫米汞柱（p<0.001），而对照组保持不变（38±3毫米汞柱；p=无显著性差异）。对60转/分钟时瞬态反应的分析显示，两组运动开始后的第一口气时VE立即增加，且两组通气模式存在类似差异。我们得出结论，PF≥40时的被动腿部运动可使CCHS患者和对照组的VE增加。在对照组中，VE与VO2和VCO2紧密耦合。然而，在CCHS患者中，被动腿部运动使PETCO2恢复正常。
