Sigmoid Volvulus Overview

Definition

• Sigmoid volvulus is a twisting of the sigmoid colon, a part of the large intestine.
• It's a common cause of intestinal obstruction in the elderly.

Etiology

• Predisposing factors for sigmoid volvulus include:
  • Chronic constipation
  • Reduced bowel motility
  • Long redundant sigmoid colon
• The exact mechanism of volvulus is unclear but involves a combination of these factors.

Pathophysiology

• The twisting of the sigmoid colon can lead to obstruction of the bowel lumen.
• This blockage prevents the passage of stool and gas.
• The resultant pressure buildup can cause significant distension in the colon above the obstruction.
• If left untreated, the impacted stool can lead to bowel ischemia and necrosis.

Clinical Presentation

• Common symptoms include:
  • Abdominal pain, often sudden and severe.
  • Nausea and vomiting.
  • Abdominal distension.
  • Constipation.
  • Obstipation.
• The pain may be intermittent.
• In later stages, signs of systemic toxicity, like fever and shock, may appear.

Diagnosis

• Clinical examination, often revealing a palpable "olive" shape mass or distended abdomen.
• Radiographic imaging, like abdominal X-ray, is often used for initial diagnosis.
  • X-ray findings may show a characteristic "coffee bean" or "inverted U" sign.
• CT scan provides more detailed information about the extent of the volvulus, potential complications and the presence of ischemia.
• Lab tests may include complete blood count (CBC) to assess for signs of infection or inflammation.

Treatment

• Immediate treatment is crucial to prevent complications.
• Initial management involves:
  • Establishing a clear airway via endotracheal intubation.
  • Intravenous (IV) fluids and electrolyte correction.
• Non-operative intervention, like decompression using a colonoscope or a tube, is attempted in cases that aren't urgent.
• Surgical intervention is necessary, particularly for cases with signs of strangulation, bowel ischemia, or when non-operative techniques fail.

Surgical Management

• Procedures involving:
  • Resection of the affected segment may be required in some circumstances.
  • De-torsion and fixation of the sigmoid colon to prevent recurrence or re-volvulus.
  • Reconstruction of the intestinal pathway to ensure proper function.

Complications

• Ischemia—reduced blood supply—and necrosis—tissue death—can occur, potentially requiring segmental resection.
• Perforation of the colon, with subsequent peritonitis.
• Sepsis and multi-organ failure can occur in severe cases.

Prognosis

• Early diagnosis and intervention are essential for a favorable outcome.
• The prognosis depends significantly on:
  • The severity of bowel ischemia at the time of presentation.
  • Pre-existing medical conditions.
  • Promptness of treatment.
• Overall, while sigmoid volvulus can be serious if left untreated, the outcomes are generally good when timely intervention occurs.

Prevention

• Prevention strategies mainly focus on managing constipation:
  • Dietary modification to include high-fiber foods.
  • Medications to promote bowel regularity.
  • Regular bowel habits.