[An attempt to estimate potentially useful parameters to evaluate the normal range of nasal peak inspiratory flow].

Introduction: Measurement of peak nasal inspiratory flow (PNIF, peak nasal inspiratory flow) seems to be a cheap and simple method to assess nasal patency. Unfortunately, due to the lack of reference values a single measurement does not take any information about the degree of nasal obstruction. Therefore, the purpose of this study was to establish parameters useful for estimating PNIF reference values.
Material and Methods: 221 respondents, from Wrocław, answered a questionnaire based on ECRHS II and ISAAC. Sample was randomized based on the personal number, stratified and representative of age and sex. Subjects were divided into three groups on the basis of their age (6-7, 13-14 and 20-45 years). The PNIF was measured using an In-Check portable nasal inspiratory flow meter (In-Check's Clement-Clark). The highest of the five PNIF values was used as the measure of PNIF for each subject in subsequent analyses (PNIF MAX). Patients with rhinitis and/or asthma were withdrawn from the study.
Results: Repeated measurements of PNIF were performed in 221 healthy volunteers. PNIF values were higher in males compared to women and this difference was statistically significant. There was a statistically significant correlation between height and PNIF MAX, and there was no such correlation between age and PNIF MAX. Stepwise linear regression that included gender, height, age revealed that only sex and height were independent significant predictors of PNIF. Obtained dependence PNIF MAX = -137.7 - 22.5 x + 1.7 y, where x is the sex (a woman, 0 - male) and the y - height. Coefficient of determination (R(2)) was 0.45 which means that regression equation explains about 45% of the observed PNIF MAX variability.
Conclusions: A correlation was found between PNIF value and sex and height of the patients, while age is irrelevant in this regard. Difficulty of establishing standards for the PNIF parameter are probably due to anatomical differences in the construction of the nose.