RT Journal Article
SR Electronic
T1 Repeatability of airway deposition and tracheobronchial clearance rate over three days in chronic bronchitis
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 1886
OP 1893
DO 10.1183/09031936.95.08111886
VO 8
IS 11
A1 CH Ericsson
A1 K Svartengren
A1 M Svartengren
A1 B Mossberg
A1 K Philipson
A1 M Blomquist
A1 P Camner
YR 1995
UL http://erj.ersjournals.com/content/8/11/1886.abstract
AB Previous investigations on tracheobronchial clearance in chronic bronchitis or chronic obstructive pulmonary disease (COPD) have usually referred to measurements during a short time-period, i.e. a few hours. The purpose of this study, therefore, was to study regional particle deposition and tracheobronchial clearance during 72 h. In 14 patients with chronic bronchitis clearance of 111In-labelled 3.6 micrograms Teflon particles and lung function were measured on two occasions, with an interval of 2 weeks. Lung retention of test particles was measured at 0, 24, 48 and 72 h using a profile scanner. The weight of expectorated sputum samples was measured after the two clearance measurements. The particle retentions at all time-points were reproducible, as seen from the two measurements ( r > 0.90). The fast clearance phase was completed within 72 h. No correlation between sputum volume and clearance was seen. There was a significant negative correlation between airway resistance and the 72 h retention (r= -0.66), and an even better correlation between specific airway resistance and the 72 h retention (r = -0.82), indicating more central deposition in obstructed airways. There was no significant correlation between lung function tests reflecting smaller airways and the 72 h retentions. Deposition data agreed well with theoretical calculations and experimental data in healthy subjects. In spite of earlier findings that mucociliary transport is usually severely impaired in chronic bronchitis and COPD, the present results indicate that overall tracheobronchial mucus clearance in these patients is fairly effective, probably due to a productive cough. Alveolar deposition may be estimated by measurements of the 72 h retention in subjects with chronic obstructive pulmonary disease. The 72 h retention is dependent mainly on the calibre of larger airways. The present method of studying airway clearance during 3 days is highly reproducible.