Studies of the mechanics of pulmonary ventilation in patients with bronchial asthma.

The chief complaint of asthmatic patient is dyspnea, but how this symptom occurs remains still considerably unknown.1)-5) Despite the ac cumulation of informations about pulmonary functions of asthmatic patients, many investigators1),4)6)7)8) have chiefly concerned the problems of lung volume, pulmonary gas distributions, ventilations and recently pulmonary circulations. Moreover, these investigators have took account only for studies in remissions or after administration of the drugs as ad renalin. According to peculiarity of this disease, the physiological investigation of dyspnea in asthmatic patient during paroxysm may include possible importance concerning to the genesis of bronchial asthma. Although this sort of study should need certainly measurements of the pressureflow relationship of the lung,9)25) many have only attempted to obtain intrapleural pressure or flow rate at the mouth separately except Sheldon and Otiss) who reported intraalveolar pressure-resistance of bronchial canalization-flow rate relationships in remissions and after administration of epinephrine. In previous study the present author observed evidently the diminution of vital capacity and one second vital capacity (or Tiffeneau's Index7)) of patients with bronchiectasis after inhalation of pilocarpin. Similarly in asthmatic patients spirograms change apparently 30-40 seconds after 1 :100 pilocarpin inhalation, and characteristic asthma-like attacks are usually induced. The present study represents an attempt to explore functionally the behavior of the pulmonary tissues and bronchial trees during such asthma-like attack induced by pilocarpin inhalation.