Related Experiment Video
Updated: Aug 12, 2026

Whole-Body Nanoparticle Aerosol Inhalation Exposures
Published on: May 7, 2013
Deposition patterns of aerosolized drugs within human lungs: effects of ventilatory parameters
1Health Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711.
Abstract:
A mathematical model for inhaled aerosolized drugs is validated by comparisons of predicted particle deposition values with experimental data from adult subject inhalation exposure tests. The model is subsequently used to study the effects of ventilatory parameters on particle deposition patterns within the human lung. By altering breathing profiles, deposition values can be affected regarding quantity delivered and spatial location. Increased tidal volumes and breath-holding times increase deposition in the pulmonary region, while increased inspiratory flow rates increase deposition in the tracheobronchial region. Based upon fluid dynamics considerations (Reynolds numbers), an original method of partitioning the lung is also presented. The model has implications with regard to aerosol therapy, indicating that the efficacies of inhaled pharmacological drugs in the prophylaxis and treatment of airway diseases can be improved by regulating breathing profiles to deposit particles selectively at prescribed sites within the lung.
Related Concept Videos
Respiratory Volumes
Tidal Volume (TV) Tidal volume (TV) is the air inhaled or exhaled in a...
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Alterations in Respiration II
In Biot's breathing, the respiratory rate and depth are irregular, alternating between periods of deep gasping and apnea. Common causes include...
Pressure Relationships in Thoracic Cavity
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs during...
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Atelectasis II: Pathophysiology

