Airflow and volume profiles involve some respiratory individual peculiarities

Abstract

The aim of our research was to evaluate the respiratory individuality during voluntary hyperventilation. 13 healthy subjects following voluntary hyperventilation protocol with the respiratory rate at 20 breaths per minute were recorded twice with one year interval. The airflow signal was decomposed by Fourier transformation into harmonics, the characteristics of first four harmonics made 8 variables complexes that can reproduce the mean airflow profile. The volume profile is represented by triplets including tidal volume, inspiratory and expiratory times. These multivariate complexes (8 variables complexes and respiratory triplets) of in two conditions (repeated recordings after one year interval) was compared by statistic test of similarity. The statistic comparison confirms the respiratory individuality in conditions of hyperventilation test.