Studies of Pulmonary Function

IN clinical medicine before World War II, pulmonary-function studies, if done at all, were limited to measuring the vital capacity and possibly the maximal breathing capacity. The arterial oxygen saturation and the acid–base relations were also occasionally determined to estimate the adequacy of respiratory function. During World War II practical problems encountered in high-altitude flying, notably those associated with pressure breathing, led to an increased interest and more extensive investigations requiring the development of new technics and improvements in the existing methods. The usefulness of the new technics in clinical medicine was soon realized. More recently, pulmonary-function studies have been . . .