Which method is commonly used to measure lung volumes?

• A. Electrocardiogram
• B. Spirometer
• C. Pulse oximeter
• D. Peak flow meter

Answer: (B)

A spirometer is the correct method for measuring lung volumes because it directly assesses the volume of air inhaled and exhaled during breathing. It provides detailed measurements such as tidal volume, vital capacity, and total lung capacity, which are essential for evaluating respiratory function and diagnosing various pulmonary conditions.

In contrast, an electrocardiogram is used to measure electrical activity of the heart and does not provide information about lung volumes. A pulse oximeter measures oxygen saturation in the blood, giving insights into respiratory efficiency but not lung volumes themselves. Similarly, a peak flow meter is designed to measure the peak expiratory flow rate, which indicates airway obstruction but does not evaluate the total lung volumes necessary for a comprehensive understanding of lung function.