Colic comes on while the animal is working, moving about, or resting, according to circumstances, and at first resembles that due to congestion. It afterwards becomes very violent; the animals paw, stamp, show great uneasiness, throw themselves violently down, and rise suddenly, only to again lie down as before. The face expresses anxiety, suffering and depression; the tail is often kept lifted, and efforts are continually made to defæcate, mucus being passed. By passing the hand into the rectum the invagination may occasionally be discovered.
Colic persists with great intensity for ten to twelve hours, interrupted only by rare periods of calm. At the end of this time, however, it may suddenly disappear, and the animal may fall into a semi-comatose state. This indicates the onset of necrosis in the invaginated section, the painful reflexes no longer being transmitted to the sympathetic system. The disappearance of colic is sometimes regarded as a sign of improvement, but this improvement is illusory. From this time onwards the animals stand stolidly, obstinately refusing both food and drink. If they lie down, it is with great care. Palpation of the right side of the abdomen is painful, and the animal actively resents it. One of the most important and constant signs at this stage is the absence of defæcation, due to obstruction of the intestine, which is occluded. The animals may survive for ten, twelve, or even fifteen days (see also Möller and Dollar’s “Regional Surgery,” loc. cit.). The invaginated, necrosed portion may even be passed with the fæces, and recovery may occur, the continuity of the intestinal tube being secured by the adhesion of the serous surfaces; but such spontaneous recoveries are exceptional. Usually after a few days death results from peritonitis.
Occasionally, trifling invaginations may become reduced spontaneously, Diarrhœa, with the passage of blood-stained material is then seen for a time, a sign which alone at this stage would justify the diagnosis of invagination.
Diagnosis. The intensity of the colic and the absence of defæcation for several days afterwards, justifies the diagnosis of invagination. Purgatives then remain without effect. In addition, rectal exploration offers a valuable means of diagnosis. The last portions of the intestine are found absolutely empty, and the arm when withdrawn is found to be covered with viscous blood-stained mucus, resulting from the sero-sanguinolent exudate, due to compression of the blood-vessels.
In cases of this kind accompanied by the above-mentioned symptoms abdominal exploration by the rectum should always be practised, but it rarely gives exact information. The hand, when passed towards the right flank, may sometimes reach the invaginated part, which conveys the impression of a cylindrical swelling. The invagination, however, can rarely be reached. If the operator is successful, he will find that as he displaces this cylindrical mass or attempts to grasp it, the animal shows signs of exaggerated sensitiveness.
The prognosis is of exceptional gravity. Apart from the rare cases where the invaginated portion becomes necrotic and is eliminated, death is inevitable. Unless an operation is performed, septic peritonitis may develop about the fifth or sixth day.
Treatment. The only treatment consists in surgical intervention. Some practitioners have recommended giving large doses of purgatives with the idea of causing changes in the neighbourhood of the invaginated part; but such treatment presents little chance of success. The same is true of the administration of large doses of olive oil, either in the form of draught or of enema.
Siebert attempted reduction by generating CO2 from soda bicarbonate dissolved in water and diluted HCl, injected successively per rectum. In time fæces and CO2 escaped, and the patient recovered. Siebert claims to have cured by this method a cow with invagination of five days’ duration; but the effect of his treatment may be doubted, as afterwards a portion of bowel was found in the cow’s dung.
When diagnosis is certain, the only treatment that can be recommended consists in performing laparotomy followed by enterotomy. One cannot, however, operate in all cases, nor do all cases offer the same chances of success. If the invagination is situated in the first portion of the small intestine, and is hidden beneath the circle of the hypochondrium, intervention is out of the question, but if it has been detected by rectal exploration in the last portion of the intestine, operation may prove successful. Only in cases of the latter description should it be attempted.
Laparotomy is performed in the right flank according to the usual method (see Möller and Dollar’s “Regional Surgery,” p. 313). After opening the peritoneal cavity, the invaginated loop of intestine must be sought. It is not always easy to discover amongst the mass of intestines present, but can be recognised by its hardness and by the congestion of neighbouring parts. After withdrawing it through the abdominal opening, the operator may then proceed by one of several methods.