An objective assessment of the tube spacer in patients unable to use a conventional pressurized aerosol efficiently.

The tube spacer, a device designed to simplify the inhalation of terbutaline from a pressurized aerosol, was objectively assessed in a group of patients with reversible airways obstruction who were found to have some difficulty in using conventional inhalers. Terbutaline was administered to 22 patients in a dose of 250 micrograms via the conventional pressurized aerosol and the tube spacer. In 16 the improvements in FEV1 were greater after the tube spacer, in four they were greater after the conventional inhaler and in two patients there was no difference. Using an open sequential plan for evaluation of paired preferences it was concluded that the tube spacer was better than the conventional inhaler in these patients.