[Determination of nasal resistance in healthy subjects using 2 technics of rhinomanometry]

Transnasal pressure-flow relationship was studied by active rhinomanometry. Nasal resistance was determined by a microprocessor assisted technique during quiet inspiration in 106 adults (49 females and 57 males) and in 52 children (21 girls and 31 boys) in various circumstances. The study was performed 1) to calculate the airflow nasal resistance (R) in different subjects, 2) to determine the laminar (K1) and turbulent (K2) coefficients of flow in the upper airways according to Rohrer's equation: R = K1 + K2 V, and 3) to compare the results of anterior and posterior rhinomanometry. The results of the experiments show that 1) nasal resistance was constant during the nasal cycle and from one week to another in the same subjects; 2) nasal resistance were higher in females than in males, and higher in children than in adults depending on nose development; and 3) the nasal resistance measured by posterior rhinomanometry (RP) was approximately twice as by anterior rhinomanometry (RA) and the correlation was highly significant. The regression line was RA = 0.82 RP - 0.06 in kPa . 1(-1) . s (r = 0.998). Anterior rhinomanometry was easier to perform than posterior rhinomanometry and more useful for performing challenges of the nasal mucosa.