Should I place a nasogastric (NG) tube in a patient with sigmoid volvulus who is very distended?

Management of Sigmoid Volvulus with Significant Distension

Nasogastric tube placement is not recommended as the primary intervention for sigmoid volvulus with significant distension. Instead, urgent flexible endoscopic decompression should be performed if there are no signs of ischemia or perforation. 1

Initial Assessment and Diagnosis

• Abdominal distension is a hallmark finding in sigmoid volvulus, often accompanied by abdominal pain, constipation, and sometimes vomiting (a late sign) 1
• Diagnostic imaging should be obtained immediately:
  • Plain abdominal radiographs as first-line imaging (look for classic "coffee bean" sign) 1, 2
  • CT scan with IV contrast if diagnosis is uncertain or complications are suspected (89% positive diagnostic yield for sigmoid volvulus) 1

Management Algorithm

Step 1: Assess for Signs of Ischemia or Perforation

• Check for peritoneal signs, fever, tachycardia, hypotension
• Obtain blood tests including lactate levels (although bowel ischemia may be present without hyperlactatemia) 1
• Silent abdomen is a valuable indicator of gangrenous bowel 3

Step 2: Choose Appropriate Intervention

If NO signs of ischemia or perforation:

• First-line treatment: Urgent flexible endoscopic decompression 1
  • Superior to rigid sigmoidoscopy (lower perforation rate, better diagnostic performance) 1
  • Successful in 60-95% of cases 1
  • After successful detorsion, a decompression flatus tube should be left in place 1

If signs of ischemia, perforation, or failed endoscopic decompression:

• Emergency surgical intervention is required 1
  • Options include sigmoid resection with primary anastomosis or Hartmann's procedure depending on patient condition and intraoperative findings 1

Important Considerations

• NG tube placement is not specifically recommended in the guidelines for sigmoid volvulus management 1, 2

  • The primary issue in sigmoid volvulus is distal colonic obstruction, not proximal GI decompression
  • NG tube may help with associated symptoms like vomiting but does not address the underlying pathology

• Recurrence risk is high (43-75%) after successful endoscopic detorsion without definitive surgery 1

  • Sigmoid distension ≥9 cm at baseline CT is associated with increased risk of recurrence (OR: 3.23) 4
  • Consider definitive surgical treatment during index admission or soon thereafter 1

• Pitfalls to avoid:

  • Delaying endoscopic decompression in patients without signs of ischemia/perforation
  • Missing signs of bowel ischemia (can occur without hyperlactatemia) 1
  • Using rigid sigmoidoscopy (can miss ischemia in up to 24% of cases) 1
  • Using barium contrast if perforation is suspected (water-soluble contrast is preferred) 1

In summary, while an NG tube may be placed for symptomatic relief of vomiting, it is not the primary intervention for sigmoid volvulus. The focus should be on urgent endoscopic decompression followed by definitive surgical management to prevent recurrence.