Heart irregularities, resulting from the inhalation of low percentages of chloroform vapour, and their relationship to ventricular fibrillation / by A. Goodman Levy and Thomas Lewis.

  • Levy, A. Goodman (Alfred Goodman)
Date:
[1912]
Catalogue details

Licence: Public Domain Mark

Credit: Heart irregularities, resulting from the inhalation of low percentages of chloroform vapour, and their relationship to ventricular fibrillation / by A. Goodman Levy and Thomas Lewis. Source: Wellcome Collection.

    15/18 page 111
    Fig. eS Fig. Fig. Fig. CHLOROFORM IRREGULARITIES. 111 5 x % An electrocardiogram from a cat under 0-5 per cent. vapour, showing marked irregularity resulting from premature ventricular contractions. Only a single normal or sequential beat is present; it is marked P, R and T, and lies in the centre of the figure. The rhythmic auricular contractions may be identified throughout the whole curve. They are marked P. 6 x 3. Shows a tachycaridia composed of premature contractions alternately generated in separate foci. This mechanism was present when the animal was upon 0-5 per cent. vapour 7 x 3 The transition from a complex tachycardia to ventricular fibrillation The tachycardia was induced by the injection of adrenalin under 0-5 per cent chloroform, the heart being originally regular. Sand 9 x 3. Two electrocardiograms from a single animal ; exemplifying the appear- ance of ventricular fibrillation, resulting from the injection of a small dose of adrenalin ; shortly after its onset (Fig. 8) and a few minutes later (Fig. 9). In Fig. 8 the oscillations follow each other at a rate of approximately 780 per minute; a series of slow undulations is present in this curve; (it is at this stage that the heart is contracted and in very active movement). In Fig. 9 the oscillations occur at a much slower rate, approximately half the preceding rate, and the slow undulations are no longer present, (it is at this stage that the heart is markedly dilated, and that the movements consist of feeble flickerings on the surface).
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