A new adaptable computerized system for the measurement of specific airways conductance

We have developed an automated system for the measurement of specific airways conductance (SGaw) which differs in several aspects from other reported automated systems. In seven subjects this system was used to measure baseline SGaw and the provocation concentration (PC) of histamine producing a 35% fall in SGaw. The results produced were compared with those obtained by manual analysis using both one limb and two limbs of the inspiratory part of the flow/box pressure curve. Using the automated system, baseline SGaw and PC35SGaw results were similar to those obtained by the two limbs method of manual analysis, but the analysis time was considerably reduced. A single measurement of SGaw was obtained within 2-3 seconds. Both the automated and two limbs manual methods of analysis were more reproducible than the one limb method of manual analysis.