Residency · Residency · General Surgery
Ostomy Creation and Reversal
Overview
An ostomy is a surgically created opening that brings a portion of bowel to the abdominal wall surface. Ostomies are common in general surgery practice and serve purposes of diversion, decompression, or definitive management. They are classified by the segment of bowel used (ileostomy for small bowel, colostomy for large bowel) and by their configuration (loop or end).
Preoperative Planning
Stoma Site Marking
Preoperative stoma site marking is an essential step that should be performed by an enterostomal therapy nurse or the surgeon. The site should be placed through the rectus abdominis muscle to reduce the risk of parastomal hernia. The ideal location is on a flat skin surface with a 5 cm radius clear of bony prominences, scars, skin folds, and the umbilicus, positioned below the belt line and visible to the patient. The site should be marked with the patient in sitting, standing, and supine positions. The right lower quadrant is typical for an ileostomy, while the left lower quadrant is typical for a colostomy. Poor stoma siting is the most preventable cause of stoma complications.
Types of Ostomies
End Ileostomy
An end ileostomy is indicated after total proctocolectomy for ulcerative colitis or familial adenomatous polyposis, following emergent subtotal colectomy, or for diversion of distal pathology. The terminal ileum is delivered through the marked site with adequate mesenteric length and without tension. Brooke maturation involves everting 2-3 cm of ileum and suturing the mucosa to the dermis, creating a "rosebud" appearance that ensures effluent enters the appliance directly. Output is liquid to semiformed, typically 500-1500 mL per day initially, and decreases as the bowel adapts.
Loop Ileostomy
A loop ileostomy is used for temporary fecal diversion, most commonly to protect a low colorectal or coloanal anastomosis or in the setting of perianal sepsis. A loop of ileum is delivered through the abdominal wall, and a supporting rod or bridge is placed beneath the loop and removed at 5-7 days. The antimesenteric border is opened, and the functional (proximal) limb is matured with eversion. Loop ileostomy is easier to reverse than an end ileostomy and is the preferred diversion method for low pelvic anastomoses.
End Colostomy
An end colostomy is indicated after a Hartmann procedure, abdominoperineal resection, Fournier gangrene, or for distal obstruction. The colon is delivered through the left lower quadrant site and matured flush or with slight eversion. Because colostomy output is formed, eversion is less critical than with ileostomy. Circumferential sutures secure the stoma to the dermis.
Loop Colostomy
A loop colostomy is used for temporary diversion for distal pathology such as rectal trauma, perineal wounds, or fistulae. It is less commonly performed than loop ileostomy and carries higher complication rates. The technique is similar to loop ileostomy, with a supporting rod placed beneath the loop.
<image>Diagram showing the four main types of ostomies (end ileostomy, loop ileostomy, end colostomy, loop colostomy) with their respective configurations and maturation techniques</image>
Ostomy Complications
Early Complications
Ischemia and necrosis are assessed by inspecting stoma color at the bedside; a dusky or black appearance is concerning. Superficial necrosis may be observed and can heal, but necrosis extending below the fascial level requires reoperation. A test tube and penlight can be used to assess the depth of viability. Retraction occurs when the stoma retracts below the skin level, risking effluent leaking under the appliance. Causes include tension on the mesentery, obesity, and inadequate mobilization, and management involves a convex appliance with a belt or reoperation if severe. Mucocutaneous separation, the dehiscence of the stoma-skin junction, is managed with wound care and pouching adaptations and usually heals secondarily.
High-output ileostomy, defined as output exceeding 1500 mL per day, is common in the early postoperative period. Management includes intravenous fluid replacement, oral rehydration solutions, loperamide, codeine phosphate, and dietary modifications. Electrolytes -- sodium, potassium, magnesium, and bicarbonate -- must be monitored and replaced. Dehydration is the most common cause of readmission after ileostomy creation.
Late Complications
Parastomal hernia is the most common long-term complication, occurring in up to 50% of colostomies and 20-30% of ileostomies. Risk factors include obesity, previous stoma site hernia, lateral to rectus placement, and a large fascial aperture. Management ranges from observation if asymptomatic to a hernia belt to surgical repair with local tissue, mesh, or stoma relocation. The PREVENT and STOMAMESH trials have shown benefit for prophylactic mesh placement at the time of end colostomy creation.
Prolapse, the telescoping of bowel through the stoma, is more common with loop and transverse colostomies. Management includes manual reduction, application of sugar to reduce edema, and surgical revision. Stenosis, or narrowing of the stoma or fascial aperture, may require digital dilation or surgical revision. Skin irritation from contact dermatitis due to effluent (especially with ileostomy), allergic dermatitis, or fungal infection is prevented by proper appliance fit and skin barrier products. Enterostomal therapy nurse consultation is essential for managing these issues.
<image>Clinical photographs showing common ostomy complications including parastomal hernia, stoma prolapse, and mucocutaneous separation with their characteristic appearances</image>
High-Output Ileostomy Management
A high-output ileostomy is defined as output exceeding 1500 mL per day, though some use a threshold of 2000 mL. It is most common in the early postoperative period and is usually self-limiting. Causes include short remaining small bowel, discontinuation of anti-motility agents, Clostridioides difficile infection, small bowel obstruction, and medications such as metoclopramide and prokinetics. The management protocol involves restricting hypotonic fluids (water, tea, coffee, juice), providing oral rehydration solutions (WHO recipe or commercial preparations), loperamide 2-4 mg taken 30 minutes before meals and at bedtime up to 16 mg per day, codeine phosphate 30-60 mg four times daily if loperamide is insufficient, omeprazole 20-40 mg daily to reduce gastric secretion volume, and intravenous fluid replacement if oral intake is insufficient. Magnesium should be monitored and replaced aggressively, as hypomagnesemia is common and often overlooked.
Ostomy Reversal
Loop Ileostomy Reversal
Loop ileostomy reversal is typically performed 8-12 weeks after creation to allow inflammation to resolve. Anastomotic integrity must be confirmed before reversal with a water-soluble contrast enema or flexible sigmoidoscopy, and adjuvant therapy should be completed first if applicable. The EASY trial demonstrated that early closure within 2 weeks reduced stoma-related complications, though this approach is not widely adopted. The technique involves a circumferential incision around the stoma, mobilization of the bowel from the abdominal wall, resection of the stoma site with creation of a stapled or hand-sewn side-to-side anastomosis, and closure of the fascia and skin. Morbidity is 10-20%, with wound infection being the most common complication, followed by small bowel obstruction, anastomotic leak, and incisional hernia. Incisional hernia at the former stoma site occurs in up to 30% of patients and represents a major long-term risk.
Hartmann Reversal
Hartmann reversal is a more complex procedure than loop ileostomy reversal and is typically performed 3-6 months after the Hartmann procedure. It requires laparotomy or a laparoscopic approach, adhesiolysis, identification of the Hartmann pouch, and construction of a colorectal anastomosis. Morbidity is 15-30%, including anastomotic leak, wound infection, and small bowel obstruction. Up to 40-50% of patients never undergo reversal due to age, comorbidities, or patient preference.
Colostomy Reversal
Colostomy reversal follows similar principles to ileostomy reversal, involving mobilization, resection of the stoma site, anastomosis, and abdominal wall closure. It carries a higher complication rate than ileostomy reversal.
<image>Surgical steps of loop ileostomy reversal showing circumferential skin incision, bowel mobilization, stapled side-to-side anastomosis, and fascial closure</image>
Enterostomal Therapy
Enterostomal therapy nurse consultation is essential throughout the continuum of ostomy care. Preoperatively, the ET nurse assists with site marking, patient education, and psychosocial support. Postoperatively, they provide appliance fitting and teach self-care. Long-term, they manage complications, provide skin care guidance, and offer dietary counseling. The psychosocial impact of an ostomy is significant, encompassing body image concerns, sexual dysfunction, and social isolation. Support groups and peer mentoring programs improve patient adaptation.
Clinical Pearls
Preoperative stoma site marking is the single most important step in preventing stoma complications and should never be skipped. An ileostomy should always be matured with a 2-3 cm Brooke eversion, as flush ileostomies cause severe peristomal skin breakdown. High-output ileostomy is the most common reason for readmission, and patients should be educated about oral rehydration solutions and anti-motility agents before discharge. Stoma viability must be checked in the early postoperative period using a test tube and light to assess perfusion below the fascial level. Anastomotic integrity must be confirmed before reversing a diverting ostomy with a contrast study or endoscopy. Prophylactic mesh placement at end colostomy creation reduces parastomal hernia rates and should be considered routinely based on current evidence. Loop ileostomy is preferred over loop colostomy for temporary diversion due to lower complication rates and easier reversal.
References
- Shabbir J, Britton DC. Stoma complications: A literature overview. Colorectal Dis. 2010;12(10):958-964.
- Wound Ostomy and Continence Nurses Society. Management of the patient with a fecal ostomy: Best practice guideline for clinicians. 2018.
- Mrak K, et al. Prophylactic mesh placement to prevent parastomal hernia (STOMAMESH). Ann Surg. 2021;274(1):e1-e6.
- Danielsen AK, et al. Early closure of a temporary ileostomy (EASY). Lancet. 2017;390(10105):1727-1734.
- Krand O, et al. Management of high-output stomas. Colorectal Dis. 2013;15(6):664-670.
