What is the management of a colocutaneous fistula?

Management of Colocutaneous Fistula

The primary management of colocutaneous fistula consists of removing the tube and allowing the fistula to close spontaneously, with surgery reserved for cases with peritonitis or failure to heal. 1

Etiology and Presentation

• Colocutaneous fistulas are uncommon but significant complications that may occur when the colon is inadvertently punctured during gastrostomy placement or when a tube erodes into the adjacent colon 1
• Patients typically present with:
  • Stool leaking around the gastrostomy tube
  • Diarrhea resembling formula during feeding
  • Fecal discharge from a wound or cutaneous opening 1
• A common scenario is when a replacement gastrostomy tube is advanced through a previously created gastrocolocutaneous fistula into the colon rather than through the colon into the stomach 1

Diagnostic Approach

• Radiographic identification is essential - a feeding tube misplaced into the colon can be visualized with contrast studies 1
• MRI is the preferred diagnostic tool for enteric fistulas, offering the highest sensitivity and specificity for defining the anatomy of the fistulous tract 2
• Assessment should include:
  • Location of the fistula
  • Volume of output (low <200 ml/day, moderate 200-500 ml/day, high >500 ml/day)
  • Patient's nutritional status and hydration
  • Presence of complications such as abscesses or strictures 2, 3

Initial Management

1. Conservative Management

   • Remove the tube and allow the fistula to close spontaneously 1
   • Fluid resuscitation and electrolyte rebalancing, especially for high-output fistulae 2
   • Nutritional support through enteral or parenteral nutrition depending on fistula location and output 3
   • Skin protection to prevent excoriation from fistula output 2, 3

2. Medical Management

   • Medications to reduce intestinal motility or secretions:
     • Proton pump inhibitors
     • Loperamide
     • Opium derivatives
     • Psyllium fibers
     • Cholestyramine 3
   • Antibiotics if infection is present 2

3. Wound Care

   • Negative Pressure Wound Therapy (NPWT) can help manage output, facilitate wound healing, and secure bag adhesion 2, 3
   • Protect surrounding skin from fistula output to prevent excoriation 3

Definitive Management

1. Surgical Intervention

   • Surgery is required when:
     • Signs of peritonitis develop 1
     • The fistula fails to heal with conservative management 1
     • The fistula is associated with bowel stricture and/or abscess 2
     • For chronic fistulas that don't respond to medical management 4
   • Surgical timing is critical:
     • Delay until the patient has recovered from acute illness
     • Allow for complete wound healing
     • Optimize nutritional status preoperatively 3
   • Surgical options include:
     • Resection of the affected bowel segment with the fistulous tract 5
     • Staged surgical procedures for complex cases 4

2. Endoscopic Management

   • Endoscopic clipping may be an option for selected cases of colocutaneous fistula 6
   • Temporary colonic stenting has been used for stoma-related colocutaneous fistulas 7

Special Considerations

• High-Output Fistulas

  • Restrict hypotonic/hypertonic fluids to <1000 ml daily 3
  • Monitor fluid output and urine sodium to guide replacement therapy 3
  • Consider partial or exclusive parenteral nutrition 3

• Inflammatory Bowel Disease-Related Fistulas

  • Anti-TNF therapy may be beneficial for low-volume fistulae associated with active inflammation 2
  • Anti-TNF therapy should only be started after abscesses have been treated with antibiotics and drainage 2
  • Approximately one-third of patients achieve fistula healing with anti-TNF therapy 2

Prevention

• Use the safe-track technique during gastrostomy placement 1
• Elevate the head of the bed with adequate gastric insufflation during placement to displace the colon inferiorly 1
• Avoid excessive lateral traction on gastrostomy tubes 1

Pitfalls to Avoid

• Initiating anti-TNF therapy before adequate drainage of abscesses can worsen sepsis 2
• Immediate surgical resection without adequate preparation (nutritional optimization, sepsis control) leads to poorer outcomes 2, 3
• Neglecting skin care can lead to significant skin breakdown and additional morbidity 2
• Failure to address associated complications (strictures, abscesses) will reduce success rates of both medical and surgical interventions 2