Parameter Identification for Respiratory Dynamics by Personalized Simulation and Experiment

Abstract

Gas flow in the airway and lung deformation due to tissue elasticity and surface tension are the main characteristics of respiratory dynamics. In this study, a simulation with the discretized model as a distributed parameter system is used extensively to identify some of the model parameters which could not be measured directly, and to estimate the real situation of lung respiration. With the use of 5 excised lungs from Japanese white rabbits, the pleural pressure vs lung volume change (Ppl-ΔV) relations are observed in situ under oscillating pleural pressure. The elastic properties of the lung tissue are measured under biaxial tension. The unknown parameters, such as that for the surface tension in the alveoli, are identified so that the Ppl-ΔV relations calculated by the simulation coincide with the experimental ones for an individual lung. The simulation studies with identified parameters demonstrate potential for estimation of the actual phenomena inside of an excised lung.