What can airway obstruction lead to in patients?

Airway obstruction primarily affects the flow of air in and out of the lungs, especially during expiration. When there is obstruction, the resistance to airflow increases, which commonly results in decreased expiratory flow rates. As air becomes trapped in the lungs due to this obstruction, it can lead to areas of hyperinflation where the lungs are over-distended with air.

This decreased expiratory flow and subsequent hyperinflation are hallmark features in various obstructive lung diseases, including asthma. In asthma patients, airway inflammation and bronchoconstriction lead to difficulty in expelling air, thereby causing reduced airflow out of the lungs and contributing to the sensation of breathlessness and wheezing.

In contrast, increased inspiratory flow rates and improved lung function are not consistent with the physiological effects of airway obstruction, as these conditions imply a more normal or improved ability to breathe, which contradicts the impact of obstruction. Normal pulmonary function tests would indicate no obstruction, which does not apply to patients experiencing airway obstructions.