[Endonasal temperature and humidity profile after exposure to various climate-controlled inspiratory air]

The nose as the first segment of the upper respiratory tract is exposed to different climatic conditions of the ambient air. The purpose of this study was to determine whether nasal air conditioning of ambient air is influenced by a short-term exposure to air of different climatic conditions.

Fifteen healthy volunteers were enclosed into the study. A miniaturised humidity sensor and thermocouple was used for detection of humidity and airway temperature at three detection sites within the anterior nasal cavity. Both parameters were measured at the end of inspiration during breathing of ambient air after exposure to cold dry air, "normal" ambient air, and warm humid air for 10 minutes.

The end-inspiratory intranasal humidity during breathing of ambient air increased at all locations within the nose when the temperature and humidity of the exposure condition increased. At the most anterior detection site, the effect of increase in humidity after exposure to the different climatic conditions was the most pronounced. The increase in intranasal temperature had no relation to the different climatic conditions during the short-term exposure.

The results suggest that nasal humidification in ambient air can be influenced by short-term exposure to air of extreme temperature and humidity prior to breathing of ambient air.