Distension of the lungs : its effect on the respiration in man and in normal and vagotomized dogs / by Walter M. Boothby and Frank B. Berry.

  • Boothby, Walter M.
Date:
[1915?]
Catalogue details

Licence: In copyright

Credit: Distension of the lungs : its effect on the respiration in man and in normal and vagotomized dogs / by Walter M. Boothby and Frank B. Berry. Source: Wellcome Collection.

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    expiration, producing an exaggerated inspiration, as shown by the pneumograph curve below point A. The following expira¬ tion is abortive, as shown by both curves. The succeeding res¬ pirations are somewhat more rapid and slightly more irregular than when breathing under normal pressure. At a and b in this Fig. I. Effect of distension on W. M. B. Spirometer weighted to give 15 cm. water pressure. Upper curve written by the recording spirometer, with in¬ spiration up and expiration down. Lower curve written by the pneumograph around the subject’s chest with inspiration down and expiration up. To be read from left to right. At A tap turned so that the subject is connected with the ' air under pressure in the apparatus. The pneumograph shows qualitatively the preceding normal respiratory rhythm; the first effect is a total expansion of the chest, followed by faster and shallower respirations. At a and b maximum in¬ spirations and expirations were made showing that the reserve air was greatly increased and the lungs markedly distended. At B the weights were removed from the spirometer and the subject then breathed air under a normal pressure. At c, d, e, and / maximum inspirations and expirations were made and are to be contrasted with those made at a and b. At C, E, and G the weights were re¬ placed on the spirometer and at D, F, and H again removed. No evidence of ap- noea either primary or secondary. Time in two seconds.