[60] It becomes a question of importance just when and where we should cease to attempt operation on the colon from above or on the sigmoid from below; in other words, the exact location of the tumor should decide the measure when it can be accurately determined. Moreover, a wide margin of bowel on either side of any new-growth which is about to be resected should be excised. The question of blood supply to the margins of the wound thus made is also of importance, as the most ideal operation in appearance may be marred by gangrene due to lack of sufficient blood supply. When there is sufficient uninvolved gut below the tumor to permit of complete operation within the abdomen it is not advisable to do anything from below; but there are some cases in which anything like complete removal can only be effected by a combination of abdominal and sacral routes. A thorough extirpation should be made above the growth as well as of the involved tissue below. Those vessels which require ligation should be tied accurately at the level of their division, and no ligation of trunks or larger vessels should be attempted at any distance from the line of division. If this be carefully carried out and the divided mesentery, with its ends, and all the fat between the rectum and the sacrum be carefully dissected out, there will rarely be difficulty in making an end-to-end reunion of the divided bowel.
It is rarely necessary to include a colostomy with this procedure; in fact, when a permanent opening has become necessary there is little possibility of removing the main growth. Colostomy is a procedure for the hopeless cases; resection is rarely to be thought of as an alternative. It should be an early not a late measure, the reverse being true of colostomy, though even this should not be too late.
Colostomy.
—Colostomy for relief of rectal cancer is not a radical operation, but in many cases is far more humane and satisfactory than are those alluded to above. The intent is to make an opening in the left side of the groin at a point where it is easily made. There are two methods of performing colostomy here. One is to make an opening through the abdominal wall, attach to it the presenting surface of the sigmoid or colon, and either open it at once or some hours later, when adhesions have cemented the desired union. Such an opening may be made for emergency purposes under local anesthesia, but when the colon is movable, and when the disease has not yet involved the area thus exposed, or any portion above it, a more desirable method is a deliberate one. An opening is made such as is usually made on the right side when operating upon the appendix. The bowel thus being accessible is divided between two clamps, while the end of the lower segment is inverted and closed with chromic or silk sutures, after which it is dropped back. This leaves the upper portion with its open end corresponding to the abdominal opening, into which it is fastened by a series of sutures, being attached to the peritoneum and to the deep musculature rather than to the skin, for if it be brought out too freely and attached externally there is greater tendency to prolapse and subsequent discomfort. Into the opening thus afforded a large-sized rubber or bent glass tube is inserted for a few inches, around which gauze is packed, and every effort is made to conduct fecal matter to the exterior, as well to protect, at least for a few hours, the wound itself from fecal contamination. Improvements in this technique have been suggested, such as tying into the bowel a curved glass tube, thus conducting its contents into a rubber bag or receptacle placed outside the dressing. Another method which has been suggested by Stewart is to connect the interior of the colon by a Murphy button with a rubber bag or rubber dam upon the outside of the abdomen, by which protection for this purpose can be afforded.
This operation makes a complete and final division of the colon, and permanently excludes the rectum with its cancerous involvement. It is not, therefore, in this respect, a radical measure. The result, however, is that if the rectum be washed from below each day it is kept far cleaner and freer from contact with irritative foreign material than it otherwise would be. Furthermore, being disused it tends to undergo to some degree a species of physiological atrophy, and, in consequence, the cancer grows more slowly, if there do not occur an apparent temporary cessation of malignant activity.
By suitable management of the artificial anus, including the deliberate emptying of the bowel every morning and the use of protective pads for receptacles, it can be made far less disagreeable than patients ordinarily fear ([Figs. 595] and [596]).
Fig. 595
Gleason’s pouch and supporter.
Fig. 596