When is a diversion ostomy considered for an adult patient with severe or prolonged ileus and a history of abdominal surgery or underlying medical conditions?

Diversion Ostomy for Ileus

Direct Answer

Diversion ostomy is NOT a standard treatment for uncomplicated ileus—it is reserved for specific mechanical obstructions or when ileus occurs in the context of severe underlying pathology requiring surgical intervention, such as fulminant colitis, perforated viscus with hemodynamic instability, or unresectable obstructing malignancy. 1

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When Diversion is Indicated in the Context of Ileus

Mechanical Obstruction Requiring Abbreviated Surgery

Loop ileostomy should be performed in severely unstable patients with right-sided obstruction when the patient cannot tolerate a time-consuming resection and anastomosis. 1

• In hemodynamically unstable patients with metabolic derangement, coagulopathy, or septic shock, damage control principles dictate performing only procedures the patient can tolerate 1
• Loop ileostomy represents a rapid, technically simple intervention that achieves source control without the risk of anastomotic leak 1
• For left-sided obstruction in unstable patients, loop transverse colostomy is the procedure of choice when resection cannot be safely performed 1

Fulminant Colitis with Ileus

Diverting loop ileostomy with intraoperative colonic lavage followed by postoperative antegrade vancomycin flushes is a colon-preserving alternative to total colectomy in fulminant C. difficile colitis. 1, 2

• This approach resulted in significantly lower adjusted mortality (17.2% vs. 39.7%) compared to total colectomy in a multicenter study 1
• The procedure is particularly valuable when ileus is present as part of fulminant colitis, as it allows both decompression and direct antibiotic delivery 1, 2
• Vancomycin flushes (500 mg every 6 hours) are continued via the ileostomy for 10 days postoperatively 1

Perforation with Peritonitis

In patients with perforation and hemodynamic instability, terminal ileostomy (not loop) should be created after resection, with the distal bowel stapled off. 1

• If open abdomen is required due to abdominal compartment syndrome risk, stoma creation should be delayed and the bowel left stapled inside the abdominal cavity 1
• Loop ileostomy is reserved only for obstruction when the pathology is not easily resectable or when an extremely abbreviated laparotomy is required 1

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When Diversion is NOT Indicated

Uncomplicated Functional Ileus

Functional ileus only rarely requires surgery—supportive measures depending on etiology usually suffice. 3

• Conservative management with bowel rest, nasogastric decompression, correction of electrolyte abnormalities, and treatment of underlying causes is the standard approach 3
• Surgery is indicated only when mechanical obstruction cannot be excluded or when complications develop 3

Postoperative Ileus

Postoperative ileus is managed conservatively and does not warrant diversion ostomy. 3

• Early mobilization, minimizing opioids, and supportive care are the mainstays of treatment 3
• Surgical intervention is only considered if mechanical obstruction is suspected or if ileus persists beyond expected timeframes with concerning features 3

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Critical Decision Algorithm

Step 1: Distinguish Mechanical from Functional Ileus

• Mechanical obstruction presents with colicky pain, high-pitched bowel sounds early, and complete obstruction to passage of stool/flatus 3
• Functional ileus presents with constant discomfort, absent bowel sounds, and may have intermittent passage of flatus 3
• CT imaging is essential to differentiate and identify transition points, free air, or ischemia 3

Step 2: Assess Hemodynamic Stability

If patient has hypotension requiring vasopressors, lactate ≥5 mmol/L, or signs of septic shock, proceed urgently to surgery with damage control principles. 1

• Goal is source control, not anatomical reconstruction 1
• Resuscitation targets: MAP ≥65 mmHg, CVP 8-12 mmHg, ScvO2 ≥70% 1
• Time from admission to surgery is critical—survival drops to 0% when surgery is delayed beyond 6 hours in septic shock with perforation 1

Step 3: Determine Surgical Approach Based on Pathology

For right-sided pathology:

• Stable patients: Right colectomy with ileocolic anastomosis 1
• Unstable patients: Right colectomy with terminal ileostomy 1
• Severely unstable patients: Loop ileostomy only 1

For left-sided pathology:

• Stable patients: Resection with consideration of anastomosis 1
• Unstable patients: Hartmann's procedure 1
• Severely unstable patients: Loop transverse colostomy 1

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Common Pitfalls to Avoid

Creating Unnecessary Stomas

• Do not create a diversion ostomy for simple postoperative ileus or functional ileus without mechanical obstruction. 3
• The morbidity of ostomy creation and subsequent reversal is substantial and includes high output, dehydration, electrolyte abnormalities, and peristomal complications 1

Performing Complex Procedures in Unstable Patients

• Avoid creating anastomoses in patients with hemodynamic instability, coagulopathy, or severe metabolic derangement. 1
• The anastomotic leak rate in emergency surgery is 4-13%, significantly higher than the 0.5-1.4% in elective cases 1

Delaying Surgery in Mechanical Obstruction with Peritonitis

• Do not delay surgical intervention beyond 6 hours in patients with perforation and septic shock. 1
• Survival drops precipitously with delayed source control 1

Creating Stomas in Open Abdomen

• If open abdomen is planned, delay stoma creation and leave bowel stapled inside the abdomen. 1
• Creating a stoma in the setting of open abdomen increases the risk of enteroatmospheric fistula 1