What is a potential cause of increased airway resistance?

Increased airway resistance can occur due to the presence of secretions in the airways. When mucus or other secretions accumulate, they can partially or completely obstruct airflow, making it more difficult for air to move in and out of the lungs. This resistance can lead to a higher work of breathing and can be associated with conditions such as asthma or chronic bronchitis. The presence of secretions creates a physical blockage that impedes airflow, resulting in symptoms like wheezing or decreased breath sounds during auscultation.

While other factors like pneumonia and fibrosis can impact overall lung function and respiratory mechanics, they do not inherently cause increased airway resistance in the same direct way that secretions do. Pneumonia may lead to more fluid and infection in the lungs, which can contribute to overall respiratory distress but involves complications beyond just airway resistance. Fibrosis involves scarring of lung tissue that primarily affects lung compliance rather than airway resistance. Low tidal volume can indicate restrictive lung disease but does not directly contribute to increased resistance in the airway, as it primarily represents a decrease in the amount of air exchanged with each breath rather than a blockage in the airflow itself.