Impact of Airways Geometry on Transport of Gases to Blood

TL;DR

This paper investigates how the structure of bronchial trees influences gas transport in the lungs, combining geometric analysis with a dynamic physiological model to improve understanding of respiratory function.

Contribution

It introduces a comprehensive model of gas exchange that incorporates airway geometry, gas dynamics, and individual characteristics, and evaluates existing bronchial tree representations.

Findings

Model accurately predicts gas exchange dynamics.

Structural features significantly impact transport efficiency.

Validation against observations supports model's validity.

Abstract

Topological structure of bronchial trees affects transport of gases and aerosols in the respiratory system. We start by providing a quantitative assessment of the ability of the alternative tree representations to predict observable geometric and mechanistic characteristics, such as network resistance, dead space volume, and path length. Then we present a model of dynamic transport of oxygen and carbon dioxide along the airways, in the alveoli, across the alveolar membrane, and along the pulmonary blood capillaries. The model also accounts for the exchange of these two gases with blood in the capillaries, as well as for age, gender and other in-species characteristics. Our model's predictions are compared with corresponding observations, providing an additional venue to assess the validity of the existing representations of the lung's bronchial tree.