[Normal values of nasal airflow measured with a newly developed rhinorheomanometer with modified Prandtle-type tube...

A new rhinomanometer with a Prandtl type tube for measuring a square relationship between nasal airflow (V2) and transnasal pressure (delta p) yielding a straight line in the V - delta p - diagram is described. This so called rhinomanogram with straight lines is like an audiogram and gives a direct reading of V in relation to delta p. The active anterior method using nozzles is employed. 337 volunteers 185 females and 152 males aged 9-76 years with normal breathing function of the nose and normal endonasal mirror findings are examined with the above mentioned rhinomanometer. The normal values of nasal airflow in relation to 15 mm H2O in l./sec. (V15) of both nasal cavities before and after shrinkage of the nasal mucosa are measured during inspiration and exspiration. For all age groups, both male and female, the normal value of V15 of the entire nose is 0,67 +/- 0,16 l/sec before and 0.81 +/- 0.17 l/sec after shrinkage of the nasal mucosa. Slight differences in the normal values of the entire nose exist between males and females of different age groups as well as during inspiration and exspiration. V15 in females is 0.63 l/sec before and 0.77 l/sec after shrinkage, whereas V15 in males is 0.73 l/sec before and 0.86 l/sec after shrinkage. With increasing age, both in males and in females, there is slight increase of V15: V15 in the age-group of 9-16 years from 0.58 l/sec before to 0.72 l./sec. after shrinkage; in the age-group of 17-40 years it is 0.66 l./sec. before and 0.80 l./sec. after shrinkage whereas in the age-group of 41-76 years it is 0.75 l./sec. before and 0.88 l./sec. after shrinkage. During inspiration V15 is somewhat lower than during exspiration. Our normal V15-values are compared with all normal values of the nasal airflow mentioned in literature by other authors.