604

INDUSTRIAL HYGIENE AND

OCCUPATIONAL

MEDICINE

METHODS

Pulmonary compartment studies were done with the patient sitting and using a modified
Benedict-Roth apparatus. The residual volume was measured by a helium dilution method.4
The maximum breathing capacity was measured in the modified Benedict-Roth apparatus for
a 15-second period. In both the maximum breathing capacity and the vital capacity measure­
ments, the largest values obtained were used if successive trials showed no further increment or
evidence of learning.
Usually three trials were sufficient. All gas volumes have been cor­
rected to body temperature and pressure conditions, saturated with water vapor at body
temperature, 37 C. (98.6 F.) (BTPS).
Standard values for the vital capacity were obtained by using the regression equation of
Baldwin, Cournand and Richards.5 The expected residual volume was calculated for each
individual, with an attempt to correct for age by using Robinson’s 6 data. The two standard
deviation ranges obtained by Robinson for the residual volume and the total capacity were
accepted as the range of normal values.
Expected maximum breathing capacity values were determined from the regression equation
of Baldwin, and associates.5 A range of normal variation of expected values was estimated
from the data of Gray and associates,7 although their observations were made on healthy young
males and females rather than on a hospitalized group. Their values had a standard deviation
± 13 per cent for males and ± 18 per cent for females. Assuming a similar variability in the
data of Baldwin and associates, we have arbitrarily used 26 per cent of the predicted value (two
standard deviations) as an estimated range of normalcy.
Arterial blood was obtained from a radial artery after 2 per cent procaine hydrochloride
infiltration. Arterial blood oxygen and carbon dioxide partial pressures (pCB and PCO2)
were determined in duplicate by the microbubble method of Riley, Proemmel and Franke.8 9
Arterial serum and whole blood C02 contents and arterial blood O2 content and capacity were
measured by the manometric method of Van Slyke and Neill.® The arterial blood pH was
calculated from pC02 and serum CO2 by the Henderson-Hasselbach equation. Expired air was
obtained synchronously with the arterial blood sample after a one to two-minute washout of the
collecting system. The mean alveolar oxygen partial pressure (p02) was calculated by the
alveolar equation, and the alveolar-arterial oxygen partial pressure difference was obtained by
subtracting the determined arterial pOi from the calculated mean alveolar pC>2.
The endocrinologic effectiveness of ACTH was measured by the fall in eosinophil concen­
tration in all instances, and by the rise in 17-ketosteroids excretion in most of the cases studied.10
RESULTS
Case i (F. F., P. B. B. H. no OE-649).—Thirty-seven years before this 53 year old
patient was admitted to the Peter Bent Brigham Hospital she had pneumonia complicated with
pleural effusion. Recovery was allegedly complete, and no further pulmonary symptoms

4. Gilson, J. C., and Hugh-Jones, P.: The Measurement of the Total Lung Volume and
Breathing Capacity, Clin. Sc. 7:185, 1949.
5. Baldwin, E. De F.; Cournand, A., and Richards, D. W., Jr.: Pulmonary Insufficiency:
I. Physiological Classification, Clinical Methods of Analysis, Standard Values in Normal
Subjects, Medicine 27:243, 1948.
6. Robinson, S.: Experimental Studies of Physical Fitness in Relation to Age, Arbeitsphysiologie 10:251, 1938.
7. Gray, J. S.; Barnum, D. R.; Matheson, H. W., and Spies, S. N.: Ventilatory Function
Tests: I. Voluntary Ventilation Capacity, J. Clin. Invest. 29:677, 1950.
8. Riley, R. L.; Proemmel, D. D., and Franke, R. F.: A Direct Method for Determination
of Oxygen and Carbon Dioxide Tensions in Blood, J. Biol. Chem. 101:621, 1945.
9. Van Slyke, D. D., and Neill, J. M.: The Determination of Gases in Blood and Other
Solutions by Vacuum Extraction and Manometric Measurement, J. Biol. Chem. 61:523, 1924.
10. Metabolic and endocrine observations on patients at the Peter Bent Brigham Hospital
were made by members of Dr. Thorn’s staff (Drs. T. F. Frawley, D. L. Wilson, and P. H.
Forsham). Similar observations on patient L. H. were made by Dr. Fuller Albright’s laboratory
at the Massachusetts General Hospital.