Clinical trial of a modified inhaler for pressurized aerosols.

Using spirometry, the effects on lung function of interposing a tube extension between a bronchodilator aerosol (terbutaline sulphate 0.25 mg) and the mouth and an ordinary aerosol have been compared. Both devices were administered with a delay of 2 s from actuating the aerosol to inhalation, thus simulating inability to coordinate properly. In 12 stable asthmatics it was found that attachment of the tube extension to the aerosol gave significantly better results for one-second forced vital capacity (FEV1.0) and forced vital capacity (FVC). The tube extension seems to be beneficial in patients with hand-lung dyscoordination.