In a patient with asthma, what happens to FEV1?

In patients with asthma, FEV1, or forced expiratory volume in one second, is commonly reduced during an asthma attack or exacerbation due to bronchoconstriction, inflammation, and increased mucus production, all of which narrow the airways and impede airflow. This obstruction leads to difficulty in exhaling air from the lungs, resulting in decreased FEV1 measurements.

The pathophysiology of asthma involves bronchial hyperreactivity, which can cause significant changes in lung function. When a patient experiences an asthma exacerbation, the constricted airways make it hard for air to flow out rapidly, significantly affecting the FEV1 values. Therefore, monitoring FEV1 is crucial in assessing asthma control and severity.

In contrast, FEV1 may remain unchanged, increase, or fluctuate dramatically under specific situations or treatment conditions, but these do not accurately reflect the typical presentation of asthma. The most characteristic finding in asthma, especially during an acute attack, is a reduction in FEV1, affirming that option regarding its reduction is the appropriate choice.