Helium-oxygen spirometry in experimental cotton dust exposure.

Abstract

Acute lung function responses to cotton dust were examined in 50 healthy adult volunteers known to respond acutely to cotton dust inhalation. Pre- and post-exposure air and helium-oxygen spirometry and specific airways conductance were employed for this purpose. Exposures were carefully controlled in a room ventilated with air from a model cardroom, lasted 6 h each, and were separated by 48 h intervals. Cotton dust exposure produced significant decrements in specific airways conductance (P 0.05). This was true for the group as a whole as well as for the various smoking subgroups. The occurrence of central (SGAW, PFR, FEV1) and peripheral (max50,max25) airways narrowing among our subjects may explain the absence of a density dependence response to the levels of cotton dust used. Since only MEFV curves were employed, however, our ability to detect changes in density dependence may have been limited by the potential effect of the vital capacity maneuver on airways tone.