**4.3 Technical and anatomic stoma-related complications**

Proper creation, management, and closure of ostomy are critical both for the treatment of specific disorders and for the peace of mind of the patient. A poor site selection contributes to the rate of stomal complications and is more likely to occur in patients undergoing emergency surgery compared with elective surgery. Other risk factors for stomal problems include:


*Gastrointestinal Stomas*

smell.

• Volume

• Transit

• Nutrition

stone formation.

The type and volume of output (effluent), and therefore fluid loss, are determined by the location of the stoma relative to the ileocecal valve. Ileostomies, cecostomies, and ascending colostomies typically produce output (effluent) >500 mL/day that contains digestive enzymes, which is irritating to the mucosa and skin, while descending/sigmoid colostomies produce stool that does not contain digestive enzymes.

The output from an ileostomy tends to be fairly watery and green or bilious in color. Within a few weeks of resumption of a regular diet, the material becomes thicker and more yellow-brown, with a watery porridge or applesauce consistency. Depending on the amount of small bowel removed, the output is looser, and the patient is more prone to dehydration. Most ileostomates notice little odor from the output, but, certain foods (e.g., eggs and fish) may produce an offensive

The ostomy output is also affected by diet, fluid intake, medications, and organic problems such as Crohn's disease or adhesions. Diarrhea, frequent loose or watery bowel movements in greater amounts, than expected, is a warning that something is not right. It can come suddenly and may cause cramps. The causes of diarrhea are variable: diet,

In a healthy individual, 1000–2000 mL of fluid passes through the ileocecal valve daily. This volume is reduced to 100–200 mL in normal stool as it passes through the colon. So a left-sided colostomy output is similar in volume and composition to the feces that would be passed transanally. The volume of ileostomy output varies fairly widely among patients but only mildly from day to day in a single individual. In the early postoperative period, the ileostomy output is 1000–1500 ml/day. In a few days, this volume is reduced to about 500 ml, even with no dietary restrictions; however it is known that fatty food and large amounts of

Resection of anus and/or colon affects the function of the proximal GI tract and the integration of endocrine and neuroenteric activities. It seems that small bowel transit time decrease after ileostomy due to adaptation to the new condition whose

Microbial flora of an individual is fairly stable over time, whereas there is great variability among individuals. After creation of an ileostomy, the distal ileum is

The colon has little role in the maintenance of normal nutrition, working primarily to absorb fluid and to store feces. Thus, removal of the colon has little effect on nutrition. However, loss of part of the terminal ileum may result in loss of bile acids and poor absorption of fat and fat-soluble vitamins. Vitamin B12 may also not be adequately absorbed in patients with terminal ileal loss that may result in pernicious or macrocytic anemia requiring monthly administration of vitamin B12. Absorption may also be impeded by ileal bacterial overgrowth. Kidney stones may be a consequence of chronic dehydration and acid urine. Adding sodium bicarbonate to the diet and increasing fluid intake may help to prevent uric acid

emotional stress, intestinal infection, antibiotics, and short bowel syndrome.

liquid increase transit and the fluidity of the effluent.

mechanisms are not yet well understood.

rapidly colonized with a variety of bacteria.

**40**

• Comorbid conditions (obesity, inflammatory bowel disease, diabetes)

The rates for stomal complications range from 14 to 79%. Peristomal dermatitis is the most common complication. Other complications include poor stoma siting, high output, ischemia, retraction, parastomal hernia formation, stomal stenosis, bleeding, and prolapse. Surgeons should be cognizant of these complications before, during, and after stoma creation, and adequate measures should be taken to avoid them [11].

Stomal and peristomal complications can occur in the early postoperative period or many years later. Complications occurring in the course of days after surgery are often related to technical issues. Those occurring within 3 months of stoma construction—necrosis, bleeding, retraction, and mucocutaneous separation—are more frequently related to suboptimal stoma site selection. Late stomal complications are generally described for permanent ostomies and include parastomal hernia, stomal prolapse, and stenosis. The site of closure of the ostomy can be associated with complications such as delayed healing, infection, and hernia formation.

Loop ileostomies have higher complication rates when compared to end colostomy or end ileostomy and with loop colostomy. The most common problems of end and loop ileostomies are dehydration, skin irritation, and small bowel obstruction. Prolapse can occur in all types of stomas but is more prevalent in loop colostomies, especially those constructed using the transverse colon.
