Mialon P, Barthélémy L, Sébert P
Service de Physiologie, Faculté de Médecine, Brest, France.
Eur Respir J. 1989 Apr;2(4):340-3.
Effects of breath holdings (BH) on bronchomotor tone, maintained until their breaking points, have been studied using maximal expiratory flow volume curves (MEFVC). BHs have been performed either at high lung volume (total lung capacity, EIBH) or at low lung volume (residual volume +250 ml, EEBH), an inspiratory manoeuvre immediately preceding the MEFVC. The results show that: (1) EIBH induces a significant increase of expiratory flow at 25% of FVC; (2) EEBH induces a significant and constant decrease of expiratory flows at 50% and 25% of FVC. The same modifications were recorded after inhalation of 400 micrograms of Fenoterol or 80 micrograms of Ipratropium bromide. The observed results are suggestive of mechanical effects of BH on expiratory flows. After EIBH airway hysteresis dominates over lung hysteresis, with opposite effects after EEBH.
使用最大呼气流量容积曲线（MEFVC）研究了屏气（BH）对支气管运动张力的影响，该影响一直持续到屏气的临界点。屏气操作在高肺容积（肺总量，EIBH）或低肺容积（残气量 +250 ml，EEBH）下进行，即在进行MEFVC之前立即进行一次吸气动作。结果表明：（1）EIBH导致在用力肺活量（FVC）的25%时呼气流量显著增加；（2）EEBH导致在FVC的50%和25%时呼气流量显著且持续下降。吸入400微克非诺特罗或80微克异丙托溴铵后记录到相同的变化。观察到的结果提示屏气对呼气流量有机械效应。EIBH后气道滞后作用超过肺滞后作用，而EEBH后则有相反的效应。
