Gayrard P, Badier M, Vervloet D, Orehek J
Respiration. 1987;51(2):81-5. doi: 10.1159/000195170.
The purpose of this study was to determine if the lung volume at which aerosol inhalation begins (LVi) influences airway responses to bronchoconstrictor agents. We compared the effects of carbachol boluses (25, 50 and 100 ml), inhaled at high and low LVi (averaging 72.2 and 15.8% of vital capacity, respectively) on specific airway resistance (SRaw). In order to eliminate the possible influence of airway obstruction on aerosol distribution and deposition, we selected 5 asthmatic subjects with normal respiratory function (spirometry, SRaw, nitrogen washout and closing volume); furthermore, non-cumulative dose-response curves were obtained (i.e. the patients inhaled only one dose of carbachol on a given test day). Inhaling carbachol at low LVi yielded a significantly (p less than 0.01) larger degree of bronchoconstriction. Differences in bronchial responses were probably due to differences in the amount of particles deposited in the airways and/or to their distribution. These data suggest that LVi should be controlled for quantified inhalation provocation tests.
本研究的目的是确定开始雾化吸入时的肺容积（LVi）是否会影响气道对支气管收缩剂的反应。我们比较了在高LVi和低LVi（分别平均为肺活量的72.2%和15.8%）时吸入不同剂量卡巴胆碱（25、50和100 μl）对比气道阻力（SRaw）的影响。为了消除气道阻塞对雾化剂分布和沉积的可能影响，我们选择了5名呼吸功能正常的哮喘患者（通过肺活量测定、SRaw、氮洗脱和闭合气量评估）；此外，获得了非累积剂量反应曲线（即患者在给定的测试日仅吸入一剂卡巴胆碱）。在低LVi时吸入卡巴胆碱产生的支气管收缩程度显著更大（p<0.01）。支气管反应的差异可能是由于气道中沉积颗粒的数量和/或其分布的差异。这些数据表明，在进行定量吸入激发试验时应控制LVi。
