Jejunostomy/Ileostomy

The ideal location for most ileostomies is in the right lower quadrant through the rectus muscle with sufficient space away from the umbilicus and skin creases to ensure adequate appliance-to-skin seal when the patient is sitting down. The creation of an ileostomy begins with the removal of a circular disk of skin with a radius of 1.5 to 2 cm (depending on the size of the patient and the thickness of the bowel loop). Subcutaneous tissue is then divided down to the anterior rectus sheath with cautery. The anterior rectus sheath is divided vertically, and the rectus muscle fibers are separated with blunt dissection. The posterior sheath and peritoneum are then sharply divided. The stoma opening should be the size of two fingerbreadths. In general, large fascial defects may predispose patients to parastomal hernias, while insufficient diameter may interfere with stoma perfusion or cause postoperative obstruction. Bowel viability must then be confirmed and may require trimming of the ileal edge to ensure appropriate bleeding. The bowel loop must then be passed through the stoma orifice, ensuring proper alignment of bowel mesentery. After the closure of the abdomen, the stoma is matured.

An end ileostomy, often created after total proctocolectomy or total abdominal colectomy, is typically fashioned with four everting stitches at the corners, which includes a full-thickness bite at the stoma edge and a subcuticular bite. Full-thickness bites between the stoma edge and subcuticular are then placed between these anchoring stitches to ensure appropriate eversion and anchoring. It is paramount to avoid stitches in the seromuscular layer altogether, as these can lead to fistulae and not to include the epidermis as mucosal islands may form and prevent appropriate flange adherence to the skin. Stitches are typically 3-0 absorbable sutures.

Loop ileostomies, used to divert in cases of delicate anastomoses, as well as in cases of obstruction, are fashioned in a slightly different manner. First, an appropriate loop of the terminal ileum should be identified. A segment at least 20 cm from the ileocecal junction will facilitate subsequent stoma reversal. When bringing the stoma loop through the aperture, care must be taken to maintain the orientation of the mesentery as well as the afferent and efferent limbs. This is often accomplished by placing a blue-dyed suture on the afferent limb (“blue to the sky”) and a brown suture on the efferent limb (“brown goes down”). After bringing the loop through the abdominal wall, an ostomy rod is typically secured underneath the loop and the distal stoma limb is opened transversely at the skin level on its antimesenteric aspect. The distal bowel edge is then secured to the subcuticular tissue with interrupted 3–0 absorbable sutures flush to the skin. The proximal lip is everted with full-thickness stitches to the dermis. When finished, the everted afferent limb should occupy about two-thirds of the stoma opening.

Colostomy

The same principles for preoperative marking apply to colostomy. They should be placed in a well-visualized, easy-to-reach part of the abdomen away from skin folds or other topography that may obstruct the appropriate placement of an ostomy appliance. Unlike small bowel, prior to delivering the ostomy loop through the aperture, adequate mobilization of colonic mesentery must take place. Attached epiploica or thickened mesentery may make it difficult to deliver the stoma through the created opening. This can be ameliorated by either dilating the fascia further or thinning out the fatty tissue. After the bowel is appropriately delivered, the surgeon should only be able to fit his or her gloved fifth digit between the fascia and bowel. If the fascial opening is too large, it can be closed with interrupted absorbable sutures. The colon should extend up to 2 cm above the skin surface; however, it need not be “Brooked” like a small bowel stoma. The matured colostomy should protrude 0.5 to 1 cm. To mature an end colostomy, the bowel edge can be everted or kept flush to the skin. Full-thickness throws should be taken through the bowel wall and then through the dermal layer of the skin. Sutures are not thrown through the serosal layer. Additional sutures are then placed circumferentially as needed.

Loop end colostomies or “Prasad” style may be utilized when there is technical difficulty in the form of reach issues of the colon reaching the abdominal wall in a tension-free manner. This happens most often when creating an end colostomy in an obese patient or those with friable mesentery. Once the bowel is delivered through the stoma opening, a supportive rod is placed through the mesentery 3 to 4 cm proximal to the cut edge, and the staple line is dunked into the subcutaneous tissue. The bowel is then opened on the antimesenteric border 3–4 cm proximal to the divided end of the bowel and the proximal limb is everted and sutured to the skin using absorbable sutures in the same manner as a typical end colostomy.

Loop colostomies have fallen out of favor in the last few decades as loop ileostomy is considered a better form of fecal diversion given their lower rates of prolapse and parastomal hernias as well as the ability to preserve the colon for future resection/reconstruction in cases of obstructing tumors. However, loop transverse colostomy or loop sigmoid colostomy can be used in extreme situations, such as obliterative peritonitis or an obstructing distal mass that is not amenable to resection. The abdominal wall is prepared similarly to end colostomy, except the opening must be much larger to provide room for two loops of bowel (at least three fingers in diameter). After mobilizing just enough bowel to reach the abdominal wall, a small window is made through the mesentery to pass a Penrose drain. A large clamp is then passed through the stoma opening that grasps the Penrose to pull the bowel through. Marking stitches of different colors can be used to mark the afferent and efferent limbs. The Penrose is then exchanged for an ostomy rod and the stoma is matured. The efferent limb is matured with full-thickness absorbable sutures. Full-thickness dermal sutures are placed at the 12:00, 3:00, and 9:00 o’clock positions on the afferent end and forceps are used to evert the edges. Further interrupted sutures are placed as needed.

Peristomal Skin Complications

Peristomal skin complications are frequently experienced by patients with an ostomy, with reported incidence ranging from 18% to 55%, and are the most common reason for visits to outpatient stoma services. ^, Complications range from minor skin irritation to serious infection, with the majority of these complications being managed conservatively or medically, without the need for reoperation. Prevention is the most important factor in avoiding these complications, which can be accomplished by putting a stoma in the correct position with proper eversion, well-fitting stoma appliances, and patient education on adequate hygiene and maintenance.

Dermatitis is the most frequently observed complication with all stoma types. By avoiding the absorptive capacity of the colon, ileostomies produce highly alkaline and toxic output that can be irritative to the skin. Risk factors for this are those with poor fitting appliances, usually in association with other risk factors including poor siting, skin folds, obesity, prolapse, retraction, and parastomal hernias. ^, Management includes keeping the area dry, using skin protectant ointments, appropriate fitting appliances, and minimizing the frequency of appliance changes. Allergic dermatitis is a less frequent cause but can be easily treated by either changing the brand of appliance used or usually a short course of topical steroids.

Folliculitis, which can result from repetitive trauma of the skin by frequent appliance removal or hair trimming, is usually self-limiting and can resolve with gentle stoma application and manipulation. A peristomal abscess can be the result of a surgical site infection or active CD leading to an underlying fistula tract. Management of abscesses includes source control, management of the underlying inflammatory disease (if applicable), and management of any sequelae of the abscess including stoma stricture and early fistula formation. ^,

High-Output Stomas

Under normal conditions, approximately 90% of nutrients are absorbed in the first 150 cm of the small intestine. Approximately 9 to 10 L of fluid enters the small bowel daily, with 6 L of absorption in the jejunum, 2.5 L in the ileum, and the remaining 1.5 L entering the colon. A high-output stoma is defined as a stoma with more than 1500 mL of daily output. These are more frequent in ileostomies than colostomies, given the absorptive capacity of the colon. Ileostomy output is affected by factors including length of bowel resection, medications, dietary choices, bacterial overgrowth, and residual intestinal disease. High-output ileostomies can be difficult to manage and lead to dehydration, acute kidney injury, and electrolyte abnormalities including hyponatremia, hypokalemia, and hypomagnesemia. ^,

The initial evaluation of patients with high-output stomas mirrors patients with acute or chronic diarrhea who have intact GI tracts. Regardless of the cause of the high output, dehydration and electrolyte imbalances should be addressed first. After that has been addressed, physicians should ensure that there is the appropriate appliance and appliance fit to avoid peristomal skin complications and provide education on dietary modifications for high output. Other strategies to reduce output include the use of antimotility agents (loperamide, diphenoxylate/atropine codeine), antisecretory agents (proton pump inhibitors, histamine antagonists, octreotide), or fiber supplementation. If feasible, surgical options such as reversal of the stoma should be considered. ^,

Parastomal Hernias, Prolapse, Retraction, and Stricture

Parastomal hernias are defined as incisional hernias associated with abdominal wall stoma and contribute to the largest portion of stoma-related complications that require surgical intervention. Factors contributing to the development of this complication include age, obesity, malnutrition, smoking, perioperative steroid use, and siting of the stoma outside of the rectus muscle. In the acute postoperative period, parastomal hernias are a result of a technical problem and should be repaired immediately. Outside of this, repairs should be reserved for those who are symptomatic and good surgical candidates. ^, Prior to surgical correction, a stoma belt, convex appliance, and regular support from a wound ostomy nurse may obviate the need for an operation.

A similar condition to parastomal hernias is stomal prolapse, which happens when a segment of bowel intussuscepts and protrudes through the stomal orifice. Risk factors include obesity, location of bowel (ileostomy, transverse, or sigmoid colostomy), creation technique (end vs. loop), and poor surgical technique. Most cases of prolapse can be managed conservatively, but stomal prolapse leading to obstruction, ischemia, or strangulation requires emergent surgical evaluation. ^{, ,}

Stomal retraction can occur due to weight gain, inadequate mobilization of the bowel segment, or poor location and fixation. This can typically be managed with convex stoma flanges and/or weight loss, but when this becomes an issue, surgical revision may be warranted. Stomal stricture is an uncommon problem and is usually related to ischemia, and in the setting of Crohn’s patients, recurrent disease should be ruled out. When this complication does occur, symptomatic patients should undergo surgical revision. ^{, ,}