Development of an aerosol dispersion test to detect early changes in lung function.
Am Ind Hyg Assoc J 1988 Jul; 49(7):357-366
An examination was made of several indexes of aerosol dispersion; an aerosol dispersion test was developed for the detection of early changes in lung function. Two of the indexes showed significant differences between smokers and nonsmokers. One of these was the relative peak height and the other was the time between inhaled and exhaled peaks. No significant difference was noted between the width of the exhaled peak at half the maximum concentration. The findings indicated that the aerosol dispersion test required approximately an order of magnitude fewer subjects than did spirometry for comparable sensitivity in detecting early lung changes caused by an inhaled irritant. Through this test epidemiologic studies could be performed on groups which previously were too small to use when only marginal differences in spirometry were expected. With the equipment used in this study there was a lack of correlation between the dispersion test results and the spirometric indexes. One reason for this lack of correlation was that the tests measured different airway functions under different physiological conditions. The low signal to noise ratio of the spirometry would be another factor. The authors caution that the dispersion test will only detect lung areas open to convective flow. If the disease has progressed to the point of closing areas to convective flow, this method will not detect the extent of the problem.
NIOSH-Author; Lung-disorders; Pulmonary-system-disorders; Pulmonary-function; Diagnostic-techniques; Diagnostic-tests; Aerosol-particles; Airway-obstruction
American Industrial Hygiene Association Journal