What component of pulmonary function refers to air remaining in the lungs after maximum exhalation?

Residual volume refers to the amount of air that remains in the lungs after a person has exhaled as much air as possible. This air cannot be voluntarily expelled and is critical for keeping the alveoli open, which facilitates gas exchange. It plays an important role in preventing lung collapse and maintaining a reservoir of oxygen-rich air to support continual gas exchange during subsequent inhalations.

Understanding residual volume is crucial for assessing lung function, particularly in conditions that affect lung capacity and function, such as obstructive and restrictive lung diseases. Other concepts related to lung volume and capacity, such as total lung capacity, functional residual capacity, and inspiratory capacity, encompass different aspects of lung function, but they do not specifically isolate the volume of air that remains after maximum exhalation like residual volume does.