How we do it: "The oral tube area method": a new method for self-assessment of nasal resistance.

KEYPOINTS

Breathing orally through a tube, 20 subjects compared their sensation of air resistance in the tube with their sensation of resistance breathing through the nose. By changing the internal cross-sectional area in the tube the subjects could choose an oral tube area where they felt the same resistance in the tube as in the nose. Expressed by the chosen oral tube area we had a measurement of the nasal resistance. The method can measure changes in nasal resistance. The method is inexpensive and easy to perform.