Objectives/Hypothesis: Adequate air conditioning in the nasal airways is ma
ndatory for respiration and gas exchange in the lower respiratory tract. Th
e aim of the present study was to measure relative humidity and temperature
in the airstream at different sites within the nasal cavity for mapping of
relative humidity and temperature in the upper airways.
Study design: Intranasal relative humidity and temperature of 23 volunteers
was measured during respiration at different locations in the nasal cavity
. Methods: The end-inspiratory temperature and humidity data, obtained with
a miniaturized thermocouple and a capacitive humidity sensor, were determi
ned Results: A high increase of humidity and temperature at the end of insp
iration, in relation to the environmental conditions, was found in the ante
rior nasal segment. The further increase of both parameters between turbina
te area and nasopharynx was less pronounced in spite of the longer distance
. Conclusions: The anterior part of the nasal cavity contributes within a s
hort nasal passage to air conditioning of inspired air.