Part 33

Lesions. In case of death the overdistension of the intestines and abdomen is the most marked lesion, the composition of the gas varying with the nature of the ingesta and the duration of the illness. Carburetted hydrogen compounds abound as a rule in the early stages, while carbon dioxide predominates later. Pinner found 49 per cent. of carburetted hydrogen, 8 per cent. of carbon dioxide, and 42 per cent. of nitrogen.

The contents of the large intestines are usually in considerable amount and in an undigested condition. The walls of the distended bowels are greatly attenuated and may show congestion, petechiæ, or rupture. Rupture of the diaphragm is not uncommon. Congestion of the lungs, but especially of the skin and superficial structures of the body, and of the brain are natural results of the expulsion of blood from the abdominal cavity.

Treatment. The desiderata are: relief from existing gaseous tension; arrest of further fermentation; and the restoration of the vermicular movement of the intestine.

The two first indications may sometimes be successfully met by stimulants and antiseptics. Formerly, mild cases were successfully treated by oil of peppermint and oil of turpentine in oil, and a free use of enemata. A more modern resort is a large (virtually soporific) dose of chloral hydrate (1 oz.) given in solution. This is at once a powerful antiferment and an antispasmodic. It is moreover highly volatile and in the heat of the stomach is readily passed on into the duodenum and absorbed. Employed early it not only checks the production of gas, but it relaxes the whole intestinal tract and allows the free passage of accumulated gas which passes off rapidly per anum.

But in severe cases the gaseous distension is too great to hope for relief by such measures and puncture of the cæcum or double colon is the only hopeful resort. This is made with a small trochar and cannula not more than ¼ inch in bore, which is inserted at the point of greatest resonance. The point usually advised, as in the ox, is the centre of the space circumscribed by the last rib, the ilium and the transverse processes of the lumbar vertebræ. A better plan is to percuss and puncture the point where the drumlike resonance is greatest. The higher the puncture the more promising as the cannula is less likely to be blocked by the ingesta which accumulates in the lower part of each viscus. The cannula may be left in place for some time to keep the bowel flaccid and allow time for the restoration of its contractile functions. The cannula may be utilized to inject antiferments (chloral) and peristaltic stimulants (eserine, pilocarpin, barium chloride). In cases in which puncture is not imperative these agents may be used hypodermically, eserine 1½ gr., pilocarpin 2 grs. or barium chloride 7 grs.

Enemata of soapsuds, with or without stimulants prove effective in emptying the floating colon and soliciting the action of the large intestines generally and the passage of flatus. Friction of the abdomen and walking exercise are desirable. After recovery a restricted diet, laxatives and bitters serve to restore the lost tone of the alimentary canal.

ACUTE INTESTINAL INDIGESTION WITH IMPACTION OF THE LARGE INTESTINES IN THE HORSE.

Definition. Causes: dessication of ingesta in colon, sacculation, constriction at pelvic flexure, debility, ill health, local peristalsis, diseased teeth, jaws or salivary apparatus, excess of food, heating grain, hard fibrous indigestible fodder, green leguminosæ, privation of water, inactivity, verminous aneurisms, tumors, strictures, obstructions. Symptoms: colics after meals, becoming more severe, tension and firmness of right side, sitting on haunches, stretching, small, hard, dry coated stools, obstruction felt on rectal exploration, frequent attempts to urinate, tympany. Course: six hours to six days or more, signs of aggravation and improvement. Lesions: large intestines tympanitic, impaction often at pelvic flexure, or other constriction, adherent mucosa has thick mucus or blood, is discolored, friable, necrosis, perforation, liquid contents of distended bowel in front, rupture, invagination, volvulus. Treatment: laxative diet, injections, aloes, pilocarpin, eserine, barium chloride, chloral hydrate, morphia, henbane, belladonna, puncture, cold or oleaginous enemata, empty or knead rectum and colon, cold compress, electricity, friction, laparotomy.

Definition. This is an impaction and obstruction of the colon, and usually of the pelvic flexure with dried and badly digested alimentary matters.

Causes. Certain anatomical and physiological conditions contribute to this disease in the horse. The ingesta as it leaves the stomach is liquid or pultaceous and throughout the small intestines it remains so, so that they are little liable to impaction. But by the time the cæcum is reached much of the liquid has been absorbed, and as the contents pass into the double colon they are usually a soft solid, which gradually becomes dried as it advances through the double and floating colon. The sacculation of cæcum and colon tends to delay the masses and favors absorption. The pelvic flexure, the narrowest part of the double colon, is formed by an acute bend of the viscus on itself so that the dried masses advancing from in front are especially liable to become arrested and impacted at this point. Impaction may, however, occur at any part of the large intestine.

Any debility or atony of the intestines predisposes to the condition. The ingesta accumulates in the portion which does not contract sufficiently to pass it onward, and this soon becomes distended to a state of absolute paresis. All conditions of debility, and all prolonged ill health tend to operate in this way by lessening vermicular movement.

Again in cases of nausea or intestinal disorder the supervention of antiperistaltic movements, will tend to accumulate the ingesta at one point and favor impaction (Ernst).

As in the case of other indigestions the imperfect preparation of the food is an active factor. Diseased teeth, jaws or salivary glands, act in this way and a functionally weak stomach contributes to this as to other intestinal disorders.

An excess of food and especially indigestible food will contribute to impaction. Heating grain, like corn, wheat, buckwheat, passed rapidly through the stomach in an imperfectly digested condition, tends to accumulate in the larger intestines. Hard, fibrous fodders like hay and straw that have run to seed, or which have been washed out by rains, bleached or heated, rye-straw, the stalks of beans, peas, vetches, which have been similarly spoiled, and clover hay affected with cryptogams or other ferments act in the same way. Even clover eaten green, produces in foals impactions to which the hairs of the leaves and chalices materially contribute (Verrier). The allied plants alfalfa and sainfoin when passed rapidly through the stomach tend to impaction of the large intestines. But any fibrous, indigestible and innutritious fodder, taken in excess to make up the deficiency of nutriment is liable to act in this way.

Other conditions that contribute to impaction are lack of water, especially at night when much hay is consumed, and lack of exercise which tends to torpor of both liver and bowels.

Finally verminous aneurisms and embolism of the intestinal arteries induce congestion, paresis, spasms, and other disorders which tend to aggregation and impaction. Also tumors, strictures and obstructions of all kinds tend to impaction.

Symptoms. A certain amount of impaction is not incompatible with ordinary health, but as this increases all grades of colic may be met with from the most simple and transient to the most persistent and severe.

In the milder forms slight and transient colics come on after meals, for days in succession, before any serious attack is sustained. These are especially marked under dry bulky fodder (hay), less so on grain, and less on green food or roots. The animal paws, moves the hind limbs uneasily, looks at the flanks, he may even kick at the abdomen, lie down and roll, rise, pass a little manure or flatus, and seeming relieved may resume feeding, until the next attack. The intermissions may last a few minutes, a quarter of an hour or longer, and they gradually become more prolonged until they disappear for the time. Sooner or later, however, the obstruction becomes more complete and the colic more severe and persistent. To the ordinary symptoms of violent abdominal pain there are added symptoms which point to bowel impaction or obstruction. There is a special tension of the right side of the abdomen, with flatness on percussion. When down there is a tendency to sit on the haunches to relieve pressure on the diaphragm and lungs. When standing there is a disposition to stretch the fore limbs out forward and the hind ones backward. Fæces may be passed at first in a few small round balls at a time, but this soon ceases, and very little or none can be obtained even by the use of enemas. The straining is usually so violent as to expel the enemata as soon as introduced. The hand introduced into the rectum can easily detect the solid impacted pelvic flexure of the colon pressing backward into the pelvis or impinging on the right pubis. Another common symptom is the frequent passage of urine in dribblets, due to the irritation of the bladder by the pressure upon it of the impacted colon during straining. In cases of this kind the colon and cæcum become tympanitic as first shown by a resonant distension of the right flank obliterating the hollow in front of the ilium, and later by a similar condition of the left flank.

The abdominal pain is usually less acute than in simple spasmodic colic or intestinal congestion. The face is less pinched and anxious, the eye less frightened, the kicking at the belly less violent, and the lying down more deliberate and careful. Very commonly the patient merely rests on his belly or side without attempting to roll.

Course. The disease may last six to twelve hours, or even as many days before it ends in recovery or death. The colicy symptoms usually increase, with the complication of dyspnœa when tympany becomes well marked, hyperthermia in case of the supervention of enteritis, and signs of general peritonitis and collapse in case of rupture of the bowel. A sudden increase of the pain may otherwise indicate the occurrence of invagination.

As indicating a favorable termination there may be restoration of the rumbling, the passage of fæces at first perhaps in the form of solid cylindroid masses, and later as a mixture of broken up ingesta, liquid and gas, the tension of the abdomen disappears, the pains lessen and cease, and there is a gradual restoration to health.

Lesions. The abdominal walls are tense and more or less drumlike, and when these are cut through the large intestines protrude strongly. When punctured there is a free discharge of gas. The most common seat of obstruction is the pelvic flexure, but it may occur in the floating colon, or rectum, in the double colon even at other parts than its pelvic flexure, in the cæcum or in the ilio-cæcal opening. The impacted mass is firm, rather dry, covered with mucus and sometimes blood, and manifestly only partially digested. Its size and form vary greatly as it is moulded into the affected viscus. The mucosa in contact with the impacted mass is covered with a thick layer of viscid mucus sometimes streaked with blood. The mucosa itself is congested, thickened, friable, and marked with spots or patches of various colors (white, gray, green,) indicating commencing necrosis. In old standing cases this may extend to the other coats of the bowel determining perforation or laceration.

The portion of the bowel immediately in front of the obstruction is filled with liquid which has been forced down upon the barrier by the active peristaltic movements, and the distension by liquid and gas may have increased until rupture has ensued with the escape of the contents into the peritoneal cavity. Invagination, volvulus and peritonitis are common.

Treatment. This will vary according to the stage and degree of the illness. In slight cases with transient colics only after meals, a more laxative diet may suffice. Boiled flaxseed, roots, potatoes, apples, green cornstalks, silage, or even sloppy bran mashes, with an abundance of good water and active exercise may prove efficient. Copious injections of warm water, soapsuds, or linseed oil emulsion may be added.

In the more violent cases we must resort to more active measures and yet drastic purgatives are full of danger. The free secretion from the vascular small intestines and the active vermicular movements, lead to the speedy overdistension of the bowel just in front of the obstruction, the current being strong and active all around the contracting gut in contact with the mucosa, while a weaker return current sets in in the centre, but is effectually checked and arrested at no great distance in front of the impaction by the strong backward peripheral stream. If therefore the impaction is not broken up, it is inevitable that the gut above must be more and more distended until a rupture ensues.

Yet in a certain number of cases a moderate dose of aloes or castor oil supplemented by frequent enemata and other measures, succeeds in safely overcoming the obstruction. The solid impacted mass is gradually softened and removed, and finally after perhaps three or four days of complete obstruction the fæces begin to pass and recovery ensues.

With or without the aloes, the hypodermic use of pilocarpin or eserine or both will often succeed in obtaining successful peristalsis. Barium chloride while inducing more active peristalsis is, on that account, somewhat more dangerous.

Pain may be moderated and fermentation checked by chloral hydrate (½ oz.), or, an anodyne, morphia (2–4 grs.), may be given hypodermically. In the absence of these, extract of hyoscyamus or belladonna (2 drs.) may be given by the mouth, and repeated as may be necessary. If tympany is dangerous use the trochar and cannula. Enemata and other accessory measures must not be neglected.