Volume 1

A system of medicine / edited by J. Russell Reynolds.

Date:
1866-1879
Catalogue details

Licence: Public Domain Mark

Credit: A system of medicine / edited by J. Russell Reynolds. Source: Wellcome Collection.

    220/976 (page 200)
    be no doubt indeed that tbe sequence of events occurs in the reverse order ; that the small afferent vessels become blocked up, and that on this blocking up supervene those changes which, according to circum- stances, end in extravasation of blood, inflammation, purulent-infiltra- tion, or gangrene. This view is partly based on direct observation in Pyaemia itself, partly on corroborative evidence derived from other sources. Thus, it has been clearly established by experiments that if a small artery leading to any spot be obstructed, that spot becomes the seat of congestion and inflammation. The careful experiments of Mr. Wharton Jones * show that, if in the frog’s foot such an artery be divided, and the capillary area to which it leads be thus cut off from all direct supply of blood, these capillaries nevertheless become filled with blood by regurgitation from neighbouring anastomising vessels ; and further, that since by the same operation they have been cut off from the direct influence of the heart’s systole, the blood which is poured into them becomes stagnant there, and intense congestion results. Again, the experiments of Cruveilhier, Sedillot,t Henry Lee \ and others, show that if mercury, oil, pus, fibrine, be injected into the veins they become impacted in the small arteries connected with the network of capillaries next beyond the seat of operation, occlude them, and induce congestion, if not haemorrhage, and inflammation in the’ respective areas to which they lead. Each of these experiments has no doubt some point of special interest, but all concur in establish- ing one common fact of fundamental importance, viz.—that the sudden stoppage of the direct supply of blood to a limited area tends to the production in that area of congestion and inflammation—of the very processes in fact which mark the secondary effects of Pyaemia. The analogies afforded by other forms of disease are still more to the point. When arteries become obstructed either from morbid changes in their walls, or from plugs in their interior, the parts which they supply fall into an unhealthy condition. It is needless to dwell upon the changes which take place in the lower extremities, when in old age the arteries become closed by accumulated ather- matous and earthy deposit, or even upon the circumscribed softenings in the substance of the heart (leading to rupture), which attend similar