Pulmonary Function in Diseases of the Chest

¹ Professor of Medicine and Director of the Cardio-Respiratory Laboratory University of Southern California School of Medicine.

An accurate evaluation of the degree of pulmonary function impairment may be made from the following physiological tests: (1) Ventilation measurements from spirogram tracings (total vital capacity, three second timed vital capacity, maximal breathing capacity and the shape of the exhalation curve following a deep breath), (2) the degree of bronchospasm present, (3) the residual air capacity and alveolar nitrogen per cent after seven minutes oxygen breathing, (4) the arterial blood oxygen saturation at rest and immediately after step-up exercise, (5) the oxygen uptake during step-up exercise, (6) the per cent of oxygen extracted from the inspired air breathed and (7) the character and duration of dyspnea after step-up exercise.