3. Compression of the bowel from abdominal tumors.
4. Contraction of the bowel from inflammatory changes, often tuberculous.
A consideration of external hernia is, of course, not included in this paper, but the possibility of the symptoms of intestinal obstruction being due to this cause should never be overlooked.
Congenital Strictures and Malformations.
Cases of congenital strictures and malformations are confined almost wholly to the rectum and anus, and come more properly under the province of the surgeon. Some of the cases, however, belong to the physician, the obstruction being so slight as not to require surgical assistance. With all of them, however, the physician should be familiar, that he may be able to distinguish between congenital malformation giving rise to immediate obstruction and other forms of intestinal occlusion. He should know, too, when to seek the aid of the surgeon. For these reasons, as well as to make the history of the causes of intestinal obstruction as complete as possible, it has been thought proper to include in the list congenital occlusion and malformation of the intestine. They will be treated, however, in the briefest possible way, and the reader is referred to works on surgery for a more detailed account of the pathology, symptoms, and treatment.
When congenital occlusion of the colon occurs, it is almost invariably found in the sigmoid flexure, and is due, as most congenital atresia of the intestine, to foetal peritonitis. Congenital occlusion may be found in any portion of the small bowel, but a frequent site is the lower part of the ileum and the ileo-cæcal opening. The following case1 gives an example of a form of stricture of the duodenum in infants, with the symptoms and pathological changes. The septum is supposed to be an unnaturally developed valve, or two valvulæ conniventes united: "A child when born presented no unusual symptoms for the first twenty-four hours. Vomiting then came on, and continued with short intermissions until death, which took place some thirty-eight hours after birth. The bowels were never relieved during life. The only disease found was stricture of the duodenum close to the entrance of the gall-duct, so that a probe passed down the latter entered the duodenum immediately below the constriction. There was nothing to indicate in what manner the constriction had occurred. On the gastric side of the latter the duodenum was immensely distended—so much so that at first sight it appeared like the pyloric end of the stomach itself, and only by a more careful examination was the distinction between the stomach and intestine detected by a ridge running around their place of junction."
1 Quoted by Mr. Pollock in Holmes's System of Surgery, from Pathological Transactions, vol. xii. p. 101.
Cases like this, a number of which are on record, are instructive and of pathological interest; when, however, congenital occlusion exists in the small intestines, no treatment can be suggested. If the sigmoid flexure is the part involved and diagnosis can be made, opening the intestine in the right groin and establishing an artificial anus should be attempted.
In the development of the foetus the anal part of the bowel, beginning below, develops upward, and the intestinal portion, commencing above, grows downward; both portions, advancing, finally unite, making one continuous tube. When, however, there is some interruption in the foetal development of the intestine, and the two portions of bowel fail to unite, we have malformation of the rectum and anus and intestinal obstruction; or the two portions of bowel may have been united and continuity of the intestinal track established, and subsequent intra-uterine inflammation may obliterate the canal. Under these circumstances a ligamentous cord represents the original tube. The cord descends from the cul-de-sac in which the upper part of the bowel ends to the skin about the anus, or is lost in the tissues about the neck of the bladder. In congenital malformations the following conditions may be found: 1st. The anal orifice may be so minute as not to allow the feces to escape; or the aperture may be occluded by a membrane, through which the meconium may be seen; or the anus may be entirely absent. 2d. The rectum may be occluded by a membranous septum, the presence of which is not suspected until symptoms of intestinal obstruction arise, and then it is discovered by introducing the finger or a probe; or the rectum may be entirely absent, the colon terminating in the iliac fossa in a dilated pouch, or ending at the top of the sacrum or stopping at any point between this and the normal anus, the place being determined by the period of arrest of foetal development; or, the anus being absent, the rectum may open into the vagina, bladder, urethra, and other places. These cases belong exclusively to the surgeon.