PANCE Pulmonology Practice Test

Reversibility after a bronchodilator is the hallmark feature that points to asthma. In asthma, the airways are inflamed and hyperresponsive, so they often dilate noticeably after inhaled bronchodilators, which shows up as an improvement in spirometry, especially the FEV1. A common teaching threshold is an increase in FEV1 of about 12% and at least 200 mL from baseline within minutes after a short-acting bronchodilator. This pattern helps distinguish asthma from more fixed obstructive conditions, where the bronchodilator effect is minimal or absent. The other scenarios don’t fit as well. No response to bronchodilators argues against asthma rather than for it, and a chronic dry cough without wheeze or being over 70 years old are nonspecific and can occur with many other conditions. So, observing a clear bronchodilator-induced improvement in airway function best indicates asthma.