Understanding pulmonary gas exchange: ventilation-perfusion relationships

This essay looks at the historical significance of four APS classic papers that are freely available online: Fenn WO, Rahn H, and Otis AB. A theoretical study of the composition of the alveolar air at altitude. Am J Physiol 146: 637—653, 1946 ( http://ajplegacy.physiology.org/cgi/reprint/146/5/637 ). Rahn H. A concept of mean alveolar air and the ventilation-bloodflow relationships during pulmonary gas exchange. Am J Physiol 158: 21—30, 1949 ( http://ajplegacy.physiology.org/cgi/reprint/158/1/21 ). Riley RL and Cournand A. “Ideal” alveolar air and the analysis of ventilation-perfusion relationships in the lungs. J Appl Physiol 1: 825—847, 1949 ( http://jap.physiology.org/cgi/reprint/1/12/825 ). Riley RL and Cournand A. Analysis of factors affecting partial pressures of oxygen and carbon dioxide in gas and blood of lungs: theory. J Appl Physiol 4: 77—101, 1951 ( http://jap.physiology.org/cgi/reprint/4/2/77 ).