What is the management plan for a patient with a small bowel obstruction (SBO) due to a Crohn's disease flare?

Management of Small Bowel Obstruction Due to Crohn's Disease Flare

Surgery is mandatory for symptomatic intestinal strictures that do not respond to medical therapy and are not amenable to endoscopic dilatation in Crohn's disease patients with small bowel obstruction. 1

Initial Assessment and Diagnosis

• CT abdomen and pelvis with IV contrast is the preferred initial imaging modality for suspected SBO due to Crohn's flare, with >90% diagnostic accuracy for detecting obstruction, identifying the cause, and evaluating for complications such as ischemia 1
• Any colorectal stricture should be assessed with endoscopic biopsies to ensure absence of malignancy 1
• Signs suggesting potential ischemia requiring immediate surgery include abnormal bowel wall enhancement, intramural hyperdensity, bowel wall thickening, mesenteric edema, ascites, and pneumatosis 1

Medical Management

First-line approach for uncomplicated SBO:

• Nil per os (NPO) status with IV fluid resuscitation and correction of electrolyte abnormalities 2
• Nasogastric tube decompression for patients with significant distension and vomiting 3
• IV antibiotics if signs of infection or ischemia are present 2
• For active Crohn's disease causing the obstruction:
  • Corticosteroids for acute inflammation (though ineffective for maintenance) 1
  • Azathioprine 1.5-2.5 mg/kg/day or mercaptopurine 0.75-1.5 mg/kg/day may be effective for treating the underlying Crohn's flare 1
  • Infliximab may be considered for refractory cases as part of a comprehensive treatment strategy 1

Surgical Management

Indications for immediate surgery:

• Signs of strangulation, perforation, or ischemia 1
• Free peritoneal perforation with radiological signs of pneumoperitoneum and free fluid 1
• Hemodynamic instability with persistent obstruction 1
• Complete obstruction that fails to respond to medical therapy 1

Surgical approach:

• For hemodynamically stable patients with intestinal obstruction: laparoscopic approach to adhesiolysis and bowel resection if appropriate expertise exists 1
• For hemodynamically unstable patients: open surgical approach 1
• Surgical options include:
  • Strictureplasty for short fibrotic strictures (preserves bowel length) 4
  • Limited resection of affected segment when strictureplasty is not feasible 4
  • For multiple or extensive strictures: combination of strictureplasty and limited resection 4

Special Considerations

• Nutritional support is essential before and after surgery for patients with diffuse small bowel disease 1
• Patients with extensive small bowel involvement may benefit from minimal surgery approaches (strictureplasty, enteroplasty) to preserve bowel length and prevent short bowel syndrome 4
• Smoking cessation is critical for maintaining remission and should be strongly advised for all patients 1
• Post-operative maintenance therapy with azathioprine/mercaptopurine should be considered to prevent recurrence 1

Prognosis

• If the initial episode of SBO can be reversed non-operatively, maintenance therapy may eliminate or postpone the need for resection 5
• Recurrent obstruction within 8 months of initial episode suggests higher likelihood of eventually requiring surgery 5
• Overall mortality for SBO is approximately 10% but increases to 30% with bowel necrosis or perforation 2

Pitfalls to Avoid

• Delaying surgery in critically ill patients with signs of ischemia, strangulation, or perforation 1
• Administering oral contrast in high-grade obstruction, which can delay diagnosis, increase patient discomfort, and risk aspiration 1
• Relying solely on plain radiographs, which cannot exclude the diagnosis of SBO 3
• Failing to distinguish between inflammatory versus fibrotic strictures, as inflammatory strictures may respond to medical therapy while fibrotic strictures require intervention 1