A smooth-bore plastic tubing with an outer helical support bead is resistant to collapse and incorporates plural conductors disposed outside of the tubing bore and insulated both from ambient and from one another within the sidewall of the tubing. The conductors may have a desired relatively high thermal conductivity to tidal air flow within the tubing, while also having a comparatively high thermal resistance relative to ambient. The conductors may be electrical conductors, or fiber optic conductors.
