Respiration

Abstract

During the past year there have appeared a number of review articles or monographs either in the field of respiratory physiology, or sufficiently closely related to be of interest to the respiratory physiologist. Volume 2 of the new Handbook of Physiology contains a chapter on the neural control of respiration by Oberholzer & Tofani (204). Bouhuys & Lundin have reviewed the general problem of the distribution of inspired gas in the lungs (33). An atlas of the submicroscopic structure of the lung in both health and disease appeared (244) that provides many fascinating details for the physiologist concerned with the structural determinants of function. Two lucid, compre hensive analyses of the kinetics of reactions between hemoglobin and gases (115) and on diffusion and simultaneous chemical reaction velocity in hemo globin solutions and red cell suspensions (232) appeared. The circulatory adaptation to hypoxia (154), the physiology and pharmacology of the pulmo nary circulation (181), and the principles of oximetry (199) were the subject of extensive reviews. Ferris (103, 104) has assembled much of the current literature on pulmonary function. Finally, special mention must be made of a scholarly essay by Richards on homeostasis (223), not directly concerned with respiration, but of interest to st u dents of the arrangements and de rangements of function in any system. MECHANICS OF RESPIRATIONUnderstanding the intimate nature of the performance of the ventilatory apparatus as a mechanical system continues to be a challenge to the respira tory physiologist. By sheer weight of number of publications under the gen eralized category "mechanics", this area of research represents the most actively studied segment of respiration. Fenn has written a lucid summary of the mechanism of breathing (100), simply presented hut profound, and singularly well suited to serve as a teaching reference in physiology.The fundamental nature of the contribution of various tissues of the lung to its "elastic" performance is poorly understood, but an appreciation of the importance of surface tension effects has been a particularly noteworthy ad vance (43) . There is apparently on the alveolar surface a peculiar material which has a coefficient of compressi bility that places it in the category of a liquid film. The surface tension of this material decreases markedly on com pression. The process is reversible if it is compressed to about 50 per cent of its surface area, but with further compression the film appears to rupture on re-expansion. This behavior is at variance with that seen in pure protei n films, and although it has not been possible to draw a firm conclusion, the 1 This review covers the literature available to the author for the period ending June 1, 1960. 123 Annu. Rev. Physiol. 1961.23:123-152. Downloaded from www.annualreviews.org Access provided by Dartmouth College -Main Library on 02/03/15. For personal use only. Quick links to online content Further ANNUAL REVIEWS Annu. Rev. Physiol. 1961.23:123-152. Downloaded from www....