Role of Endoscopy in the Management of Acute Colonic Pseudo-Obstruction and Colonic Volvulus
Patient Guideline Summary
- We will use the abbreviation ACPO throughout this summary to refer to acute colonic pseudo-obstruction.
- Colonic volvulus describes the twisting of a loop of the large bowel that obstructs the flow of its contents and threatens its blood supply. ACPO occurs when flow in the large bowel stops without a physical obstruction.
- Causes of colonic volvulus include a cancer mass and a floppy loop of the bowel. Colonic volvulus can occur anywhere in the large bowel.
- Sigmoid volvulus usually occurs in elderly men in poor health.
- Cecal volvulus most often occurs in younger women.
- ACPO is the result of a failure of the nerves that regulate bowel motion and occurs mainly in acutely ill elderly patients.
- Symptoms of both conditions include abdominal pain, bloating, nausea, vomiting, and altered bowel function.
- Complications — dead bowel, perforation, sepsis, shock, and death — are guaranteed unless the obstruction is relieved and the blood supply is restored.
- This patient summary focuses on the management of sigmoid and cecal volvulus.
- The initial evaluation should include a focused history, physical examination, and basic laboratory assessment.
- In stable patients, colonic volvulus is often initially evaluated with plain abdominal x-rays.
- Computed tomography (CT) imaging may be used to confirm the diagnosis.
- Because recurrence is common, treatment includes the prevention of repeated episodes.
- High-risk patients require urgent treatment. They have unstable blood pressure, and evidence of perforation or peritonitis (infection in the abdomen).
- Patients with uncomplicated volvulus should typically undergo colonoscopy (looking inside the colon with a flexible telescope) to assess sigmoid colon viability, untwist the anatomy and decompress the colon.
- Urgent surgical sigmoid resection (removal) is indicated when endoscopic untwisting of the sigmoid colon fails and in cases of a dead or perforated colon.
- Patients who undergo successful endoscopic detorsion (untwisting) should be considered for sigmoid colectomy during the same hospital admission to prevent recurrent volvulus.
- Other methods of preventing recurrence are available for frail patients, but they are inferior to the removal of the sigmoid colon.
- Segmental resection is the preferred treatment for patients with cecal volvulus.
Acute Colonic Pseudo-Obstruction
- The initial evaluation should include a focused history and physical examination, baseline laboratory values, and diagnostic imaging.
- Initial treatment of ACPO is supportive and includes eliminating or correcting conditions that predispose patients to ACPO or prolong its course.
- Pharmacologic treatment with neostigmine is indicated when ACPO does not resolve with supportive therapy.
- Endoscopic colonic decompression should be considered in patients with ACPO in whom neostigmine therapy is contraindicated (unsafe) or ineffective.
- Surgical treatment is recommended for ACPO complicated by colon ischemia (inadequate blood supply) or perforation or ACPO refractory (unresponsive) to pharmacologic and endoscopic therapies.
- ACPO: Acute Colonic Pseudo-obstruction