The Effects of Ultrasonically‐produced Aerosols on Airway Resistance in Man

The effects of inhalation of aerosols produced by ultrasonic and by heated nebulizers on airway resistance of ten normal subjects and ten patients with chronic bronchitis or asthma were determined with a body plethysmograph. Normal subjects were unaffected by the solutions administered by the heated nebulizer, but inhalation of solutions nebulized by ultrasound caused an increase in airway resistance in all. When isoproterenol was inhaled by patients immediately prior to the inhalation of the ultrasonic aerosol, no change in airway resistance was seen. Atropine did not modify the responses of patients to the ultrasonic aerosol.