INTESTINAL OBSTRUCTION. 125 
CHAPTER IV. 
INTESTINAL OBSTRUCTION. 
In this instance obstruction signifies not merely constipation but an acci- 
dent which as a rule proves exceedingly dangerous. 
Considering the fact that dogs are accustomed to swallow hair, bits of wood, 
glass, stones, and other indigestible substances, stoppage would seem likely to 
occur often among them; yet as a matter of fact it is not common, thanks to the 
provisions of nature, which make it possible for almost anything that can pass 
through the throat, to journey down and out of the alimentary canal. The 
exceptions to this are few, and include substances that have sharp points, which 
obviously render them liable to become fixed on the way. 
But there are other causes of obstruction. Sometimes it results from a 
twist or knot in the intestine. Sometimes, also, it is occasioned by what is 
termed intussusception, which is the slipping of one portion of the intestine, 
stove-pipe like, into another, in which case the outer part contracts and holds 
the inner fast. 
By strangulated hernia is meant the imprisonment of a part of the bowel 
in an opening in the abdominal wall, which constitutes what is popularly called 
a “rupture.” In umbilical hernia, for instance, the bowel produces the char- 
acteristic appearance ; and generally the knob-like protrusion yields to pressure, 
and can be forced back. As long as this is possible there is no obstruction ; 
but if the tissues which constitute the hernial ring become inflamed or affected 
by spasm, the opening is narrowed, the intestine pinched, and passage through 
it obstructed. 
Obstruction may occur in consequence of pressure from tumors, also organs 
that are greatly enlarged by disease. Again, it may be the result of long- 
neglected constipation, matters that should be thrown out accumulating and 
forming a mass which the lower bowel has not the power to expel. Finally, cases 
of obstruction are encountered in which the cause cannot be determined. 
Only by the selection of a typical case of intestinal stoppage for an illustra- 
tion can an adequate idea of the symptoms be conveyed. Pain is usually the 
first manifestation sufficient to attract attention, although in some instances an 
insignificant diarrhoea or constipation may have previously existed. The pain 
is severe, colicky in character, and recurs at short intervals. Indeed, the symp- 
toms at this stage are identically those of colic, for which obstruction is commonly 
mistaken and treated. 
