Respiratory physiology.

A basic review is presented of the anatomy and physiology of the airways and the alveolar - capillary interface. Lung volumes are defined, as are terms used in pulmonary function testing, and alveolar ventilation is discussed. Five common mechanisms of arterial hypoxemia are explored and some common examples are presented, and the value and limitations of arterial blood gas determinations and pulse oximetry in the Emergency Department setting are discussed.