What is the main purpose of pulmonary function tests?

The main purpose of pulmonary function tests is to assess the efficiency of gas exchange in the lungs. These tests measure various aspects of lung function, including airflow, lung volumes, and the ability of the lungs to transfer gases such as oxygen and carbon dioxide between the air and the bloodstream. By evaluating how well the lungs are working, pulmonary function tests can help diagnose conditions such as asthma, chronic obstructive pulmonary disease (COPD), and restrictive lung diseases.

The tests provide critical information about lung capacity, the flow of air during inhalation and exhalation, and how effectively oxygen enters the blood. This assessment is vital in determining the severity of any pulmonary disease and guiding treatment options. In contrast, the other choices pertain to entirely different physiological measurements that do not relate to lung functionality; they are focused on cardiovascular health and metabolic factors rather than the respiratory system.