Terbutaline aerosol from a metered dose inhaler via a 750 ml spacer. Effect on large and small airways.

The effect on large and small airways of a pressurized terbutaline aerosol delivered via a 750 ml spacer, or via an ordinary actuator, was investigated in a double-blind study of 15 patients with reversible obstructive airflow disease. There was significant bronchodilatation with both devices as measured by Raw, FEV1.0, PEFR, MEF75, MEF50, and MEF25. Raw showed, a significant difference in favour of the 750 ml spacer. Measurement of Closing Volume (CV) revealed a significant decrease with the spacer, but with the ordinary actuator there was a slight increase in CV; the difference between the devices was significant. The quotient Closing Volume/Vital Capacity (CV/VC%) was significantly decreased with the 750 ml spacer but not with the ordinary actuator. The decrease in volume of isoflow (VisoV) was more pronounced with the spacer but not significantly so. The results suggest that use of a 750 ml spacer may promote more extensive peripheral deposition of the drug in the bronchial tract.

RCT Entities:   Population Interventions Outcomes