How to Perform Rigid Sigmoidoscopy

• Indications:
  • Rectal bleeding
  • Lower abdominal and pelvic trauma
  • Extraction of foreign bodies
  • Stool cultures
  • Evaluation and biopsy of ileoanal pouch
• Contraindications:
  • Anal stricture
  • Acute perirectal abscess
  • Acutely thrombosed hemorrhoids
• Anesthesia:
  None
• Equipment:
  • Rigid sigmoidoscope and obturator
  • Light source
  • Suction apparatus
  • Insufflating bulb
  • Water-soluble lubricant
  • Long cotton-tipped swabs
  • Biopsy forceps, if desired
• Positioning:
  Lateral decubitus, lithotomy, or prone jackknife
• Technique:
  • Administer tap water or saline enema before procedure to empty distal colon of feces.
  • Perform a digital rectal examination to assess for masses.
  • Assemble sigmoidoscope by placing the obturator through the scope. Check light source and suction. Lubricate the scope thoroughly with water-soluble lubricant.
  • Gently insert the sigmoidoscope through the anus to 5 cm, remove the obturator, and attach the light source.
  • Judiciously insufflate air to visualize the lumen, using the minimum amount of air necessary to see.
  • Slowly advance the sigmoidoscope as a unit to visualize the rectum. Air will leak during the procedure, and intermittent insufflation will be necessary.
  • The lumen of the sigmoid will be posterior toward the sacrum and then gently curving to the patient's left. To minimize the risk of perforation, advance the sigmoidoscope only when the lumen is clearly visualized.
  • If stool is obstructing the view, use the cotton-tipped swabs to clear the lumen.
  • Advance the sigmoidoscope under direct vision as far as tolerated by the patient (most rigid scopes are 20 cm long) (see Figure 5.4).
  • To biopsy a mass or polyp, advance the scope until part of the mass is within the barrel of the scope. Insert the biopsy forceps into the barrel, and grasp a specimen of tissue. If needed, silver nitrate sticks may be used to achieve hemostasis.
  • • Systematically inspect the mucosa while withdrawing the instrument slowly.
  • Complications and Management:
    • Bleeding
      • Usually self-limited, but may occur after biopsy.
      • Rarely will require treatment, but if bleeding is hemodynamically significant, then resuscitate and consider endoscopic treatment.
    • Perforation
      • Manifested by abdominal pain, distention, and loss of hepatic dullness to percussion.
      • Obtain upright chest radiograph; free air under the diaphragm confirms the diagnosis.
      • IV fluids, IV antibiotics, urgent operative management.