Romero-Colomer P, Manresa F, Escarrabill J
Allergol Immunopathol (Madr). 1985 Mar-Apr;13(2):135-41.
We submitted eight asthmatics (age range 24-51 years) to progressively increasing doses of inhaled methacholine. Mechanical studies were done before and after each dose of methacholine and also after an inhalation of 240 micrograms of Ipratropium Bromide (IB). Recordings included: Thoracic gas volume at FRC (TGV), airways resistance (Raw), flow volume loops and static pressure/volume relationship (Pst/V). Exponential fitting of Pst/V curve was done according to previous studies, and maximal flow/static recoil curves were drawn with the data previously obtained. Considering the variation of SGaw as an index of airway reaction we found a good correlation between this parameter and MEF. Cdyn and the slope between MEF. The increase of TGV was in good correlation with SGaw as a percentage of control value. We could not find any significant variation in Specific Distensibility (Dsp) or Pst max. Our results support previous studies that have shown a insignificant modification of the elastic properties of the lung. The volume increases observed by plethysmography must be cautiously interpreted. We suggest that this modification may be the result of various factors, i.e. technical, mechanical (airways collapse, air trapping) and biological factors (surface forces, alveolar relaxation). Our data confirms the predominant central action of Ipratropium Bromide.
我们让8名哮喘患者（年龄范围24 - 51岁）吸入剂量逐渐增加的乙酰甲胆碱。在每次吸入乙酰甲胆碱之前和之后，以及吸入240微克异丙托溴铵（IB）之后均进行了力学研究。记录内容包括：功能残气量时的胸廓气体容积（TGV）、气道阻力（Raw）、流量 - 容积环以及静态压力/容积关系（Pst/V）。根据先前的研究对Pst/V曲线进行指数拟合，并利用先前获得的数据绘制最大流量/静态回缩曲线。将气道比传导率（SGaw）的变化作为气道反应的指标，我们发现该参数与最大呼气中期流速（MEF）、动态顺应性（Cdyn）以及MEF之间的斜率具有良好的相关性。TGV的增加与作为对照值百分比的SGaw具有良好的相关性。我们未发现比顺应性（Dsp）或最大静态压力（Pst max）有任何显著变化。我们的结果支持先前的研究，这些研究表明肺弹性特性的改变不显著。通过体积描记法观察到的容积增加必须谨慎解释。我们认为这种改变可能是多种因素导致的结果，即技术因素、力学因素（气道塌陷、气体潴留）和生物学因素（表面力、肺泡松弛）。我们的数据证实了异丙托溴铵主要的中枢作用。
