Assessing nasal resistance in Japanese children by active anterior rhinomanometry

Objectives: The mean bilateral nasal resistance in normal Japanese adults is 0.25±0.12 Pa/cm3/s, but this value in children remains unknown. This study aimed to determine the mean nasal resistance values in Japanese children.Methods: We measured nasal resistance in a normal rhinosinal status and rhinosinal morbidity in elementary school children by active anterior rhinomanometry. We used a nasal nozzle that has been recommended for the standard measurement of nasal resistance by the Japanese Standardization Committee on Rhinomanometry.Results: The mean value of bilateral nasal resistance at ΔP 100 Pa in 1204 normal children was 0.35±0.13 Pa/cm3/s on inspiration and 0.37±0.14 Pa/cm3/s on expiration (ΔP is an abbreviation for the pressure gradient). Nasal resistance in children decreased with growth, making it difficult to determine a single value of nasal resistance in normal children. The mean value of bilateral nasal resistance at ΔP 100 Pa in 838 children with nasal problems, including marked adenoidal hypertrophy, was 0.56±0.87 Pa/cm3/s on inspiration and 0.55±0.47 Pa/cm3/s on expiration.Conclusions: Bilateral nasal resistance is significantly greater in children with nasal morbidity than in normal children. Additionally, nasal resistance in normal children is best assessed according to the body height category.