Respiratory Research volume 17 , Article number: 78 Cite this article. Metrics details. The knowledge of where particles deposit in the respiratory tract is crucial for understanding the health effects associated with inhaled drug particles.
An ex vivo study was conducted to assess regional deposition patterns thoracic vs. Experiments were set using an original respiratory tract model composed of a human plastinated head connected to an ex vivo porcine pulmonary tract. The model was ventilated by passive expansion, simulating pleural depressions.
Aerosol was administered during nasal breathing. Planar scintigraphies allowed to calculate the deposited aerosol fractions for particles in the three size ranges from sub-micron to micron The deposited fractions obtained, for thoracic vs. Results obtained with this new ex vivo respiratory tract model are in good agreement with the in vivo data obtained in studies with baboons and humans.
The effectiveness of aerosol drug delivery mainly depends on the amount of active agent penetrating the respiratory tract as well as on its regional distribution. This information is crucial for predicting the beneficial health effects associated with inhaled drug particles.
Many inhalation studies were mainly focused on the assessment of the total deposited fraction often calculated by comparison between inhaled and exhaled fractions or used computational approaches, for instance, the recent Euler-Lagrangian approach of Kannan et al.
