La topografia del broncospasmo indotto da aerosol ultrasonico di acqua distillata

The central or peripheral site of bronchospasm induced by ultrasonic aerosol of distilled water was investigated in a sample of 5 healthy non smoker subjects and in another one of 5 patients with latent asthma. The following measurements were performed: lung volumes, SGaw, MTT and partial flow-volume curve recorded while breathing air and after a 10' whash-in with a He 80%-O2 20% mixture. After the challenge 2 reference subjects and all the latent asthmatics show significant variations of one or more of the assessed indewes, suggestive to a various extent of a prevalent central site of fog-induced bronchospasm. The occurrence of a density -non-dependence of flow with the 2 reference subjects before the stimulus, confirms the specificity of the challenge, as the latter phenomenon indicates an early airway obstruction, compatible with hyperreactivity. From the results the indication may be drawn to the application of various methods to the detection of response to ultrasonic fog, so as to assess the airway status at various levels.