MECHANICAL TESTING AND INVERSE ANALYSIS FOR DEVELOPING A MATERIAL MODEL OF LUNG PARENCHYMA

Abstract

The mechanical ventilation of patients with Acute Respiratory Distress Syndrome (ARDS) and Acute Lung Injury (ALI) is a life saving treatment. However, insufficient understanding of lung mechanics can cause overstraining of the parenchymal tissue resulting in additional inflammatory injuries. These ventilation induced lung injuries (VILI) are mainly occurring in the alveolar tissue. The goal of our research is to improve mechanical ventilation, and thus to reduce the frequency and severity of VILI. Our research focuses on the development of different computational models that should serve a better understanding of the lung [Wiechert, 2007]. We are working on different projects concerning this complex multiscale problem. Since VILI occur mainly in the alveolar tissue, this work concentrates on a better understanding and modeling of this tissue. Our aim is to come up with accurate material models of parenchymal lung tissue. Currently our work is based on two material models for soft biological tissue that are already implemented in our research code [Holzapfel, 2001], [Itskov, 2006]. By mechanically testing tissue slices we will be able to determine appropriate material parameters of alveolar tissue more precisely and use these in our model development.