[Mass spectrum analysis of expired and alveolar gas during separate bronchospirometry]

It is possible to measure with a mass spectrometer the oxygen and carbon dioxide pressure in expired gas and alveolar gas in each lungs during a separate bronchospirometry. In 15 cases out of 26 (of which 21 had broncho-pulmonary cancers) it was possible to trace serious disorders of the alveolar-capillary exchanges in the diseased lung, probably related to an altered ventilation-perfusion relationship. This technique brings more data to the physio-pathologist than the plain measurement of the oxygen consumption of the diseased lung.