Variability of Tracheobronchial Clearance in Healthy Non-Smoking Subjects

Abstract

Tracheobronchial clearance was measured twice in 10 healthy non-smoking volunteers to evaluate inter- and intrasubject variability, using a radio-aerosol technique (5 μm ^99mTc-labelled polystyrene particles). By means of two detectors radioactivity in the lungs was measured at regular intervals for 6 h and once more 24 h after inhalation. The decrease in radioactivity after correction for background activity, isotope decay and 24-hour retention was assumed to reflect tracheobronchial clearance. Among other parameters to quantitate the results of these tests, the area under the retention curve up to 6 h after inhalation (AUC-6) was calculated. The intersubject coefficient of variation (COV) using the AUC-6 was 31 %. The intrasubject COV of the AUC-6 was 11 %. These results compare favourably with those reported by others using different techniques. It is concluded that the intrasubject variability of tracheobronchial clearance as measured by this technique is small.

Polystyrene Microspheres as a Specific Marker for the Diagnosis of Aspiration in Hamsters

“…Labeled polystyrene microspheres given by inhalation have also been used in human studies for measurement of mucociliary clearance rates and airway resistance (17)(18)(19)(20)(21)(22). In our study, there was no evidence of penetration and accumulation of microspheres within extrapulmonary organs.…”

Airspace Dimension Assessment with Nanoparticles (AiDA) in Comparison to Established Pulmonary Function Tests

“…PSL particles have been used extensively to study translocation, clearance, and ventilation in both human and animal lungs. [40][41][42][43][44][45] These, and similar studies with other types of particles, 46,47 show that the translocation of nanoparticles to other organs is very limited for particles in the range 40-100 nm. In-vitro studies with human lung cells exposed to PSL particles showed indistinguishable effects from controls.…”