Chest
Clinical InvestigationsRegional Impairment of Mucociliary Clearance in Chronic Obstructive Pulmonary Disease
Section snippets
Selection of Subjects
We selected nine patients who satisfied the American Thoracic Society definition of COPD8 and who had evidence of expiratory flow volume limitation on tidal respiration.6 In addition, ten volunteers with no history of lung disease and normal flow volume curves were recruited by advertisement. The presence of chronic flow-limitation can be assessed by observing the relationship between the tidal flow-volume loop and the MEFV curve. The individual flow volume curves of all subjects are shown in
RESULTS
Clinical and spirometric data for all subjects are shown in Table 1. The subjects are classified as normal or those with COPD as discussed before. Further, they are subdivided into iron oxide and sebacate deposition groups. There were ten normal subjects (four with iron oxide and six with sebacate deposition). There were nine COPD subjects (four with iron oxide and five with sebacate deposition). The normal group was younger than the COPD group (mean age ± SD = 35 ± 16 years and 56 ± 9 years,
DISCUSSION
This study demonstrates that patients with COPD and chronic flow limitation on tidal breathing have delayed MC that disproportionately affects airways in the central region of the lung. Evidence for the regional impairment is provided by serial sC/P analysis and by classic retention curves. Since MC is thought to be faster in central airways than in peripheral airways in normal subjects, 17, 18 the sC/P ratio would be expected to decrease as inhaled particles are cleared from the central
ACKNOWLEDGMENT
The authors thank Roger Grimson, Ph. D., Department of Preventive Medicine, State University of New York at Stony Brook, for statistical advice.
REFERENCES (28)
- et al.
Characteristics of tracheobronchial deposition and clearance in man
Ann Occup Hyg
(1982) - et al.
Mucociliary clearance in adult asthma
Am Rev Respir Dis
(1992) - et al.
Interpretation of “24 hour lung retention” in studies of mucociliary clearance
J Aerosol Med
(1988) - et al.
Effect of flow-limiting segments and cough on particle deposition and mucociliary clearance in the lung
Am Rev Respir Dis
(1979) - et al.
Flow limitation on expiration induces central particle deposition and disrupts effective flow of airway mucus
Ann Occup Hyg
(1988) - et al.
Location of flow-limiting segments via airway catheters near residual volume in humans
J Appl Physiol
(1985) - et al.
The flow-volume curve: a current perspective
Am Rev Respir Dis
(1973) - et al.
Flow-volume curves during quiet breathing, maximum voluntary ventilation and forced vital capacities in patients with obstructive lung disease
Scand J Respir Dis
(1967) - American Thoracic Society Committee on Diagnostic Standards: Standards for the diagnosis and care of patients with...
- et al.
Relationship between tracheobronchial particle clearance rates and sites of initial deposition in man
Arch Environ Health
(1989)
Cough enhanced mucus clearance in the normal lung
J Appl Physiol
Flow limitation, cough, and patterns of aerosol deposition in humans
J Appl Physiol
Enhancement of particle deposition by flow-limiting segments in humans
J Appl Physiol
Measurement of tracheal and bronchial mucous velocities in man: relation to lung clearance
J Appl Physiol
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Supported by grants HL-00461, AI-16337, HL-31429-07, and ES07088 from the National Institutes of Health.
Manuscript received March 3; revision accepted September 14.