STUDIES OF TOTAL PULMONARY CAPACITY AND ITS SUBDIVISIONS. V. NORMAL VALUES IN FEMALE SUBJECTS

Abstract

Determinations of total pulmonary capacity and its subdivisions have been made in 50 healthy [female] subjects, of an average age of 23.1 yrs. Considerable variations were found in the absolute values, but they were closely correlated with combined physical and radiological measurements of the chest, as was the case in the normal male subjects. A formula has been derived for the prediction of the corresponding pulmonary capacity in a given case. The relative values (total capacity = 100%) presented a rather fixed range of variation. The respiratory "dead space," calculated from the tidal volume and the CO2 percentages of the tidal and alveolar airs, varied proportionally with the tidal volume, being independent of the respiratory rate.