DILATION OF THE INTESTINE.
Capacity adapted to ingesta, rich and nutritious food improves breeds, excessive filling renders paretic, dilates; obstructions, impactions, strangulations, hernias, invaginations, twisting, tumors, compressions, calculi, lowered innervation, impaired circulation, verminous aneurism, peritonitis, persistent umbilical vesicle in horse and ox, hernia of mucous through muscular coat, cæcal dilatation, colic, rectal, with atresia ani, diseased end of cord, retained fæces. Symptoms: colics after meals, abdominal and rectal exploration, softer than impaction. Treatment: empty mechanically or by laxatives, demulcents, kneading, stimulants, nux vomica, ergot, barium chloride, eserine, rich concentrated food, electricity, enemata, laxatives.
It is a physiological law that the intestine developes in ratio with the demands made upon it, provided these demands are not too sudden and extreme. Thus the domestic pig and rabbit have intestines at once longer and more capacious than those of the wild varieties. The same is true of cattle and even of horses, heavy, rich feeding, generation after generation, increases the capacity to take in and utilize more, and to attain to a larger size and earlier maturity. In such a case the walls of the intestinal canal retain their primary thickness and strength and the whole change is in the direction of physiological improvement for economical ends.
When, however, the retention or habitual accumulation of food in the alimentary canal exceeds the self-adapting powers of its walls a true pathological dilatation takes place, and attenuation or thickening and paresis or actual paralysis of the walls ensues.
Whatever interferes with the normal active movement of the ingesta predisposes to this. Thus partial obstructions of all kinds, strictures, impactions, strangulations, hernias, invaginations, twisting, tumors, compressions, calculi, contribute to the overfilling of the bowel in front of them and to its more or less speedy dilatation. Whatever weakens the muscular walls of the bowels or the nerves presiding over these has a similar effect. Thus pressure on the solar plexus or its branches from any cause, or degeneration of the same, a tardy and imperfect circulation resulting from verminous aneurism and thrombosis, and a circumscribed peritonitis extending from the serous to the muscular coat of the bowel act in this way.
The persistence of the canal of the umbilical vesicle has been repeatedly observed in solipeds, in the form of a pouch or dilatation connected with the ileum three or four inches in front of the ileo-cæcal valve. Rauscher records one of these of thirteen inches long and having a capacity of seven quarts. These have been noticed in cattle as well.
Another form of sacculation results from rupture of the muscular coat through which the mucous forms a hernial sac in the peritoneal cavity. On a small scale these sacs are not uncommon, the size of a pea, a bean, or a marble, and very often containing larval or mature worms. Degive records an enormous dilatation of the horse’s cæcum, Peuch, one of the pelvic flexure of the colon having a capacity of forty pounds, and Simonin one of the floating colon. Dilatations of the rectum always take place in the new born affected with atresia ani.
Dilatation of the rectum into a cloaca is found in the horse and ox, often connected with disease or injury of the terminal part of the spinal cord, and is very common in dogs and cats in connection with the compulsory retention of the fæces indoors. Pigs also present instances of the kind.
The symptoms are in the main slight colics, with or without tympany and recurring after each meal. In the small animals the distended gut may often be recognized by palpation through the abdominal walls, and in the larger animals by rectal exploration. The distended viscus has not the firmness nor hardness of impaction or calculus and is mainly recognizable by its bulk and form. When the distension is in the rectum it may be easily reached and contents dislodged with the effect of giving complete relief for the time being.
Treatment. Treatment is necessarily mainly palliative and consists in the removal of abnormal accumulations. From the rectum this can be done with the hand, or in the smaller animals with the finger. For abnormal dilatations more anterior, purgatives and mucilaginous injections are required, with kneading of the bowels through the abdominal walls, or through the rectum in the larger animals, and stimulation of the peristalsis by nux vomica, ergot, barium chloride or eserine.