Plate 59

The right transverse colostomy is preferred by many over cecostomy for decompression of the obstructed colon due to a left-side lesion. This procedure completely diverts the fecal stream and permits an efficient cleansing and preparation of the obstructed colon proximal to the lesion. When simple diversion of the fecal stream is needed as a complementary component of an elective colonic operation, the surgeon should consider placement of a proximal diverting loop ileostomy (see Plate 58).

Since this procedure is usually performed to relieve acute obstruction of the left colon, the preoperative preparation is limited to the correction of fluid and electrolyte imbalance as well as blood volume deficits. Flat and upright roentgenograms of the abdomen are made with a marker, such as a coin, on the umbilicus. An emergency water-soluble contrast enema is indicated to locate conclusively the left-sided point of obstruction. A sigmoidoscopic or colonoscopic examination may be done. Prophylactic antibiotics are administered intravenously within one hour of incision.

Usually, endotracheal anesthesia, which provides a cuff for secure closure of the trachea, is indicated to avoid aspiration of regurgitated gastrointestinal contents.

The patient is placed in a comfortable supine position with the proposed site for the incision presenting.

The incision is placed in the right upper quadrant. A vertical or transverse incision can be made in a location over the distended colon as indicated from a study of the abdominal roentgenograms. Currently it is believed that the opening should be made through the rectus muscle with consideration being given for the span of the ostomy appliance gasket, which should be away from skin folds, bony prominences, or the valley of the umbilicus. Marking is further discussed in the section on loop ileostomy. The tentative site should be checked with the patient standing and sitting and taking special note of the proximity to the patient's belt line which should be avoided. The opening into the abdomen, while limited in length, must be large enough to permit easy identification and mobilization of the tightly distended transverse colon. If the bowel is tightly distended, it is essential to deflate it through a large needle or trocar, since the collapsed bowel can thus be handled more easily and safely.

A knuckle of transverse colon is delivered into the wound, and the omentum is retracted upward. If the intestine is tremendously distended, a large-bore needle attached to a syringe is inserted obliquely through its wall to allow gas to escape. Decompression through a small trocar attached to a suction apparatus may be indicated before the distended bowel can be safely mobilized. If necessary to avoid contamination, the small opening is closed with a purse-string suture. Under such circumstances the decompression of the bowel permits a safe delivery of a larger segment of the transverse colon through a smaller incision. The greater omentum, which is frequently more vascular than usual under these circumstances, should be dissected free of the colon that is to be used as a colostomy (Figure 1). All bleeding points should be ligated before replacing the omentum in the abdomen. The principle utilized is similar to that described in Plate 27, Figures 1 and 2. Some surgeons prefer to pass a curved clamp through an avascular portion of the omentum and transverse mesocolon beneath the colon, following which a finger is inserted as a guide (Figure 2). The omentum is divided over the presenting portion of the transverse colon and reflected to either side (Figure 3). It may be necessary to divide several small blood vessels where the omentum is attached to the colon above the anterior taenia. After an adequate through-and-through opening has been made beneath the transverse colon, a sterile large rubber catheter (equal to 32 French) is inserted as the finger is removed (Figure 4). The rubber catheter tip is cut off and one end is inserted into the other point. This joint is then secured with a nonabsorbable suture (Figure 5). The use of a rubber tube instead of a solid glass or plastic rod allows it to flex into an ostomy appliance. A liberal amount of transverse colon should be exteriorized to ensure a complete diversion of the fecal stream.

The fat tabs on the loop of bowel are now anchored to the adjacent peritoneum with fine sutures, great care being taken not to penetrate to the lumen of the bowel (Figure 6). The use of sutures in anchoring the intestine to the parietes is advantageous, since these will serve as a guide to the individual layers when the colostomy is closed. In the presence of great distention where the intestinal wall is quite thin, it is wiser to depend upon the fixation of the intestine by the glass rod, since perforation of the intestine may take place with resultant leakage and peritonitis if sutures are taken to anchor the bowel to the abdominal wall.

If a very liberal incision was necessary to deliver the dilated intestine, the peritoneal opening may be partially closed by interrupted fine sutures (Figure 7). The peritoneal closure should not constrict the arms of the knuckle of the intestine but should permit the introduction of the index finger directly into the peritoneal cavity about the intestine. The fascia is approximated with interrupted 00 sutures (Figure 7). In general, this fascial closure should allow the passage of one finger plus the loop. The subcutaneous tissue and skin are closed in a similar manner (Figures 8 and 9). Subcuticular interrupted absorbable sutures may be used to provide a firm closure and a wound less likely to be irritated by the subsequent constant fecal soilage. The ostomy is matured in most cases. A transverse incision is made. The distal or inactive stoma is matured first by placing fine 0000 absorbable sutures that transverse the thickness of the colon bowel wall. The suture is completed as a traverse subcuticular bite beneath the skin edges. The proximal or active stoma is then matured in a similar fashion. In some cases it may be preferred to delay the opening of the stoma, in which case tube drainage of the proximal limb is sometimes used.

It is usually better judgment to open the colostomy before the initial dressings are applied rather than to delay 2 or 3 days to avoid possible infection of the wound, since the dangers of unrelieved obstruction are greater than the possible complications of wound infection. A transverse incision in the taenia should not be made, for the bowel may be almost half divided, and subsequent closure of the colostomy may thus be made unnecessarily difficult. Invariably, the opening appears to become larger after the colon returns to its normal size (see Plate 60).

A short incision should be made in the midportion of the presenting taenia (Figure 8). All bleeding points are transfixed and tied with fine suture material. At this point, the skin is cleaned and prepared with a benzoin-like compound for immediate application of a large ostomy appliance. The advantage of a flexible rubber tube become immediately apparent now and each time the ostomy appliance is changed. Alternatively, some prefer to mature the colostomy at the time of surgery or to relieve the obstruction by inserting an open-ended catheter proximally through a purse-string suture (Figures 9 and 10). The rubber catheter is usually removed in 10 to 14 days; however, shrinkage of the edematous loop to a normal-sized colostomy may take the better part of a month.

In cases of acute obstruction, it may be desirable to continue constant gastric suction for several days. Following this, the patient is given fluids the first day and a soft diet for the next few days, progressively increasing to a high-vitamin, high-calorie, high-protein, low-residue diet. Early ambulation is permitted. Irrigations of the proximal colon may be given through the colostomy opening in preparation for secondary surgical procedures or to establish regular emptying of the colostomy if the colostomy is to be permanent. Following diversion of the fecal stream, the reaction about the obstructing tumor tends to subside and the obstruction may be relieved. Through-and-through irrigations for cleansing purposes may then be possible. Blood transfusions, high-calorie solutions, and Ringer's solution are given as required, depending on the degree of the patient's debility. Antibiotic therapy is discontinued after a few days or so unless the patient has a continuing infection.