Studies of Total Pulmonary Capacity and Its Subdivisions. V. Normal Values in Female Subjects

Abstract

Studies of the total pulmonary capacity and its subdivisions have been made in this clinic during the last two years, in an attempt to obtain a quantitative estimation of the degree of functional disability in cases of chronic pulmonary disease. It was found that the normal values gathered from the literature were insufficient to afford an adequate basis for the detection of pathological alterations, and preliminary studies were consequently made in healthy subjects. The results of measurements made in fifty normal male subjects have been presented in previous papers (11), (12). The data show definite limits of variation for the relative values of some of the subdivisions of the total pulmonary capacity, as well as a definite correlation between the pulmonary capacity and combined physical and radiological measurements of the chest. By means of these measurements the pulmonary capacity in a given normal adult male subject can be predicted with a fair degree of accuracy. Since it seemed probable that the same formula can not be applied in the case of normal female subjects, a similar. series of observations has been made in them. The results are presented in this communication. METHODSAs in the previous study, the total pulmonary capacity and its subdivisions were measured by means of Christie's method of oxygen dilution without forced breathing. Complete details will be found in that author's original description (5), and further details as to its use in this clinic are given in the first paper of this series (11). It may be mentioned, that we have become more convinced of the desirability of measuring the residual air by this method, rather than the volume of air remaining in the lungs at the end of a normal expiration (called " functional residual air " by Christie and " mid capacity " by us).' By

The Lung Volume and Its Subdivisions in Normal Boys 10-17 Years of Age 1

“…for inspiratory capacity, expiratory reserve and residual volumes, respectively. Lung volume studies of normal adults using the open-circuit method (28) or various modifications of the closed-circuit method (9,22,(25)(26)(27)(32)(33)(34) cannot be compared with our data for boys because of the effect of age upon the various subdivisions and because in most cases the tests were conducted in the sitting posture (22,(27)(28)(29).…”

“…The present study gives further proof of its usefulness. It is generally recognized that less variability is encountered when the volumes of the various subdivisions are expressed as percentages of the total lung capacity (9,22,(25)(26)(27)(28)(29) (11-13, 31, 32). The open-circuit method introduced by Darling, Cournand and Richards (15), however, appears to allow fewer sources of error.…”

“…In Figure 1 (3) 0 _ and the non-logarithmic values and therefore add nothing to accuracy of prediction within the height range studied. In the case of adults the relative proportions of the total lung capacity occupied by the different subdivisions have been shown to be more constant than the absolute volumes of the subdivisions (9,22,(25)(26)(27)(28)(29). For the children of this study mean values for successive age groups, as well as the overall mean values for each subdivision, are given in Table V The data show no consistent change in the relative volumes of the various subdivisions which may be attributed to age.…”

Studies of Total Pulmonary Capacity and Its Subdivisions. Viii. Observations on Cases of Pulmonary Fibrosis

“…The limits of variation in normal subjects, both male and female, and the method for the prediction of the normal capacity of a given subject have been described (1) (2) (3). The purpose of the present communication is to correlate the anatomical findings with measurements of the total pulmonary capacity and its subdivisions in 58 cases of pulmonary fibrosis.…”

Studies of Total Pulmonary Capacity and Its Sub-Divisions. Vi. Observations on Cases of Obstructive Pulmonary Emphysema 1

“…However, the changes are so constant and well marked that we do not believe that the general conclusions will be altered. It may be mentioned here that in the cases of the two female patients the normal values found for this sex (4) have been used for comparative purposes.…”