Predicting particle deposition in an adult human lung using an oscillatory, lumped respiratory model

Inhalation has become widely accepted as the optimal drug delivery mechanism for respiratory diseases, which often requires targeting a particular region of the lung. Mathematical models are key to understanding the factors that influence drug transport and deposition in the lung. This study proposes a simple zero-dimensional typical path model that couples respiratory mechanics and particle deposition over multiple oscillatory breathing cycles. Respiration is modeled using an RLC (resistance–inductance–capacitance) circuit analog framework to capture airflows, lung pressures, and volumes. The model is validated against experimental deposition fractions reported in the literature. The model is used to explore the effects of oscillatory respiration and multiple breaths on particle deposition in different regions of the lung. The results indicate that oscillatory dynamics are important in compliant airways. Deposition increases over multiple breaths as the concentration of suspended particles increases in the respiratory airways.