Reduction of a linear complex model for respiratory system during Airflow Interruption

Abstract

The paper presents methodology of a complex model reduction to its simpler version - an identifiable inverse model. Its main tool is a numerical procedure of sensitivity analysis (structural and parametric) applied to the forward linear equivalent designed for the conditions of interrupter experiment. Final result - the reduced analog for the interrupter technique is especially worth of notice as it fills a major gap in occlusional measurements, which typically use simple, one- or two-element physical representations. Proposed electrical reduced circuit, being structural combination of resistive, inertial and elastic properties, can be perceived as a candidate for reliable reconstruction and quantification (in the time and frequency domain) of dynamical behavior of the respiratory system in response to a quasi-step excitation by valve closure.

Wearable Interrupter Module for Home-Based Applications in a Telemedical System Dedicated to Respiratory Mechanics Measurements

“…A practical test must also address the issue of the clinical relevance of the reduced models applied in the time and frequency domains. Depending on the level of simplification, diverse structural-parametric description can be proposed for the EIT: analog, similar to the equivalent used by Peslin [15], [23] or DuBois [9]. Computer simulations and preliminary real measurements conducted with the time/frequency procedures of data analysis in our laboratory have shown that these structures can be used in a complementary manner to assess the mechanical status of the lungs.…”

“…Instead of passing over the dynamic changes observed just after occlusion (backextrapolative procedures), as is typical for IT, the EIT, using the idea of indirect measurement and information contained in postocclusion transient states, deduces the complex mechanical nature of the respiratory system more precisely. The formulation of an inverse model for the interrupter measurement and a procedure to estimate the parameters of this model were needed for this task [15], [16]. The classical occlusive algorithm was also replaced with a fusion-like procedure, which uses information contained in the time-(pressure and flow signals measured at the mouth) and frequency-domain (real and imaginary parts of the input interrupter resistance) characteristics [8], [9], [14], and their parametric and nonparametric indices.…”

Internal validation of a telemedical system for monitoring patients with chronic respiratory diseases

“…This application exactly mimics the operation of a home unit: it is labeled by a specific serial number, accepts configuration files from the server, enables the selection of a given patient from the list and the date from the unrolled calendar, can set the ambient pressure, and finally is used to generate spirometric or interrupter data. The both tests are simulated using computational models for the respiratory system [16,19]. The generated data are individualized by rescaling procedure, with parameters depending on the date of simulated examination (as in Fig.…”

Analysis of Properties of a Lung Mechanical Model During Artificial Ventilation Using Measurement Station

“…The standard version of the IT measurement protocol generates quick flow interruption (100 ms standard) and results in fast airway opening pressure rise P ao [16]. An exemplary plot is shown in Fig.…”