What is the treatment approach for Small Bowel Obstruction (SBO)?

Treatment Approach for Small Bowel Obstruction (SBO)

Non-operative management should be the initial approach for all patients with SBO unless there are signs of peritonitis, strangulation, or bowel ischemia. 1

Initial Assessment and Diagnosis

• Key clinical findings to identify:

  • Prior abdominal surgery (most reliable risk factor)
  • Constipation
  • Abdominal distension
  • Abnormal bowel sounds
  • Signs of strangulation (fever, hypotension, diffuse abdominal pain, peritonitis) 2

• Imaging:

  • CT scan with contrast is the preferred imaging technique for diagnosis of SBO
  • CT helps differentiate complete vs. partial obstruction and identify signs requiring urgent surgery:
    • Closed loop obstruction
    • Bowel ischemia
    • Free fluid 1

Management Algorithm

1. Non-operative Management (First-line for most patients)

• Components:

  • Nil per os (NPO)
  • Nasogastric tube decompression (for patients with significant distension and vomiting)
  • IV fluid resuscitation
  • Correction of electrolyte disturbances
  • Nutritional support as needed 1

• Water-soluble contrast agents (WSCA):

  • Reduces failure rate of conservative management (17% with WSCA vs. 50% without) 1
  • Protocol: 100 ml Gastrografin within 24h of admission with follow-up X-rays 1

• Duration:

  • Trial of non-operative management for 72 hours is considered safe and appropriate
  • Continuing beyond 72h remains debatable if high output from decompression tube persists without clinical deterioration 1

2. Surgical Management (For specific indications)

• Indications for immediate surgery:

  • Signs of peritonitis
  • Strangulation
  • Bowel ischemia 1

• Indications for surgery after failed non-operative management:

  • Persistent obstruction after 72 hours of conservative management
  • Clinical deterioration during non-operative management 1

• Surgical approach:

  • Laparotomy is the traditional approach of choice
  • Laparoscopy may be considered in select cases (35% of cases in some studies) 1
  • Higher rate of negative explorations reported with laparoscopy compared to open surgery 1

Special Considerations

Malignant Bowel Obstruction

• Requires additional considerations including:
  • Endoscopic stenting options
  • Palliative care discussions in advanced disease
  • Poorer prognosis (median survival 26-192 days) 3

Nasogastric Tube Use

• Not all patients require NG tube placement
• Patients without active emesis may be safely managed without NG tubes
• NG tube placement associated with increased risk of pneumonia and respiratory failure 4

Outcomes and Recurrence

• Surgical management is associated with:

  • Lower recurrence of SBO symptoms (34.8% vs 57.4% with conservative management)
  • Fewer rehospitalizations for SBO (14% vs 29.4% with conservative management) 5
  • However, surgical management carries 7.4% risk of requiring additional surgery for recurrent SBO 5

• Overall mortality for SBO is approximately 10%, but increases to 30% with bowel necrosis/perforation 6

Common Pitfalls to Avoid

• Delaying surgery beyond 72 hours in patients with persistent complete obstruction
• Failing to recognize signs of strangulation requiring immediate surgery
• Overreliance on plain radiographs (cannot exclude SBO diagnosis) 2
• Unnecessary NG tube placement in patients without significant vomiting or distension 4
• Neglecting fluid and electrolyte resuscitation during non-operative management

By following this algorithm-based approach with careful patient assessment and appropriate timing of surgical intervention when needed, outcomes for patients with SBO can be optimized.