Physiology, Airway Resistance

Excerpt

The lungs are an intricately designed organ that acts as the body's center for gas exchange, inhaling and exhaling approximately 7 to 8 mL of air per minute per kg while exchanging oxygen for carbon dioxide. Airway resistance is an essential parameter of lung function and results from the frictional forces of the airways, which oppose airflow. At physiologic levels, airway resistance in the trachea is responsible for turbulent airflow, while airway resistance in the bronchi and bronchioles allows for more laminar airflow, in which air smoothly flows to the distal segments of the lungs. When airway resistance is elevated, as seen with certain pulmonary diseases, air can become trapped in the lungs, limiting gas exchange and possibly causing respiratory failure in severe cases.