Ventilation‐perfusion ratio: A Mathematical Approach for Gas Exchange in the Lungs

Abstract

Chronic pulmonary diseases and respiratory infections remained as one of the most morbid and deadliest diseases in the world. Airway and environment play an important role in the etiology of these pathologies. The balance between oxygen and carbon dioxide exchange is the pillar of the respiratory system. The ventilation ‐ perfusion ratio (VPR) determines the efficiency of gas exchange in different areas of the lung. For a long time the lung was assumed to be divided in three regions that would have homogenous VPR. Recently it was established that the VPR changes in a more heterogeneous fashion. The aim of this project is to understand the gas exchange in each alveoli using a mathematical model that produce the VPR architecture based on airways architecture. The model assumed mass balance, the ideal gas law and diffusional forces. Parameters for the model were determined according to data obtained in the literature and their correspondent mathematical calculus. The model was implemented in MATLAB (The MathWorks®, Inc.)and the equations were solved to steady state. The model predicted gas concentrations and flows in different lung segments. We were able to model healthy an pathological situations. In addition, we also simulated environmental influence in the small airways. The mathematical model was helpful to understand the gas exchange dynamics. It could be used to predict the interaction between ventilation and perfusion under different conditions, giving the possibility to estimate the efficacy of medical intervention. It can also shed some light on how to prevent anddecrease the incidence of lung diseases. Support or Funding Information Department of Biomedical Engineering, Universidad de los Andes, Bogota, Colombia This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .