Chronic emphysema is associated with what specific spirometry reading?

Chronic emphysema, a form of chronic obstructive pulmonary disease (COPD), is characterized by the destruction of alveolar walls and the loss of elastic recoil within the lungs. This leads to air trapping due to narrowed airways and impaired expiratory flow.

In patients with emphysema, spirometry readings typically show an increased residual volume. This is because, with the destruction of the alveoli, the ability to fully exhale air is compromised. As a result, residual air remains in the lungs after exhalation, leading to elevated levels of residual volume. The presence of air trapping can contribute to hyperinflation of the lungs, which can be visualized on imaging and is evident in the pathology of the disease.

In contrast, decreased total lung capacity would not be characteristic of emphysema since the total lung capacity may remain normal or even increase due to hyperinflation. Airway resistance is typically increased rather than decreased because of the obstruction and collapse of small airways. FEV-1, which measures the forced expiratory volume in one second, is usually decreased in emphysema due to the obstructive nature of the disease.