The indirect measurement of nasal airway resistance

This is a comparative study of two indirect methods for measuring nasal airway resistance. 1. In 499 patients, nasal airway resistance was studied with the alternating pressure principle. Using mathematical and computer analysis, nasal resistance averaged 18,7 and 15,4 mm H2O/1/sec., respectively. This correlates well with literature data of nasal resistance, as defined by different methods. 2. In 760 patients nasal airway resistance was studied with the body plethysmograph. The mean value was 11,5 mm H2O/1/sec. We believe, that there is a methodical failure due to leakage of the mask during exspiration against a mechanical closing mechanism of the body plethysmograph.