The effect of section of the vagi on the respiration of the cat / by J. Trevan and E. Boock.

  • Trevan, J. W. (John William)
Date:
[1922?]
Catalogue details

Licence: In copyright

Credit: The effect of section of the vagi on the respiration of the cat / by J. Trevan and E. Boock. Source: Wellcome Collection.

    5/12 page 333
    If the section passes through the anterior colliculi (level II) the effect of the division of the vagi is much less marked. There is slight slowing Figs. 2, 3, 4. Effect on respiration of section of the vagi after decerebration. Fig. 2. De¬ cerebration at level IV of Fig. 1. The interval between a and b was 20 mins. Fig. 3. Decerebration at level II. Both vagi divided at the arrow. Gap in the tracing about 3 mins. Fig. 4. Decerebration at level III. The abdominal movement precedes the thoracic. and compensatory deepening, shown in the tracing given in Fig. 3. Measurements of the tracing give the following results : Depth Rate Minute volume Before section ... 21 28 588 After „ . 24 23 552 If the section passes between the colliculi (level III), division of the vagi gives a greater deepening of the respiration, and a curious in¬ coordination of the respiratory movements usually shows itself at this stage, especially, and sometimes only, on increasing the dead space of the tracheal cannula. It consists of a time dissociation of the abdominal and thoracic respiratory movements. It is illustrated in Fig. 4. The inspiratory movement is downwards, and the first wave on the curve at A was found by inspection at the time of the experiment to be
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