Human airway diameters derived from aerosol inhalation studies — reproducibility of data

With a new aerosol inhalation technique effective airway diameters (EADs) of the human lungs as function of volumetric lung depth (LD) can be evaluated. The estimation of airway diameters is based upon measurements of gravitational losses of 1 mu m-particles during respiratory pauses from a monodisperse aerosol applied at a constant concentration during a single breath. It was the purpose of this study to determine the reproducibility (intra-subject variability) of this technique and to investigate the influence of the mouth cavity upon evaluated airway diameters.