Frequency-domain identification of the respiratory system model during the interrupter experiment

Abstract This paper is the first in a series devoted to the metrological evaluation of the interrupter technique (IT). The aim of it is to propose effective modification of the classical algorithm and to summarize the research concentrated on evaluating the usefulness of the pressure and flow data frequency analysis on the estimation of the mechanical status of lungs. Based on the Frey et al. reports, a physical–mathematical representation of the respiratory system (modified DuBois’ model) was used. The electrical analog expresses the division of the physiological object into the tissue and airways segments. For such a theoretical structure, the optimal configuration of the measurement signals and the tools of their analysis have been simulated by means of forward–inverse modelling. At this stage, the possibility of expanding the inference on the system mechanics was shown. At the same time, the improvement of repeatability and evaluation precision in relation to the known IT realisation was observed.