Gastrointestinal fistula is one of the severe complications in gastrointestinal surgery, caused by trauma, surgical injury, severe intra-abdominal infections, chronic intestinal inflammation, and tumors. Clinically, it is classified into high and low fistulas; high-output and low-output fistulas; tubular and lip fistulas.

bubble_chart Diagnosis

1. There is often a history of surgery, trauma, or severe intra-abdominal infection.
2. In the early stages, when gastrointestinal contents have not perforated the abdominal wall and accumulate in the abdominal cavity, there are often manifestations of intra-abdominal infection. When turbid and foul fluid drains from the wound or abdominal drainage site after gastrointestinal surgery, gastrointestinal fistula should be suspected, and further examination should be conducted for confirmation. Once gastrointestinal contents are observed draining from the incision or drainage site, a definitive diagnosis can be made.
3. When gastrointestinal fistula is suspected, activated charcoal or dye can be administered orally, and observation should be made to see if it overflows from the wound or drainage site. The location of the fistula can be determined based on the duration of its excretion.

bubble_chart Treatment Measures

1. Early and adequate drainage to control intra-abdominal infection: In patients with signs of peritonitis after gastrointestinal surgery or abdominal trauma, when a fistula is suspected, exploratory laparotomy should be performed. If a gastrointestinal fistula is confirmed, thorough peritoneal lavage should be performed, and drainage tubes should be placed for adequate drainage. Multiple drainage sites or double-lumen tube continuous negative pressure suction may be necessary if required. Antibiotics should be selected based on bacterial culture results to control infection.
2. Maintaining nutrition: For high-output fistula patients who cannot resume oral intake, total parenteral nutrition (TPN) via deep venous catheterization should be administered, providing 167–209 kJ (40–50 kcal) per kilogram of body weight per day and 0.2–0.3 g of nitrogen per kilogram (equivalent to 1.3–1.95 g of protein per kilogram). For some high fistulas, a nasogastric tube can be inserted into the distal intestine beyond the fistula, or a jejunostomy can be performed. Alternatively, a tube can be inserted through the fistula opening and advanced to the distal side for tube feeding or elemental diet administration until oral intake is possible.
3. Local fistula management: ⑴ Tubular fistula: After 2–4 weeks of adequate drainage, if intra-abdominal infection is controlled and gastrointestinal discharge gradually decreases, the drainage tube can be gradually removed until the fistula heals spontaneously. ⑵ For large fistulas with short tracts or lip fistulas, silicone sheets can be used for internal occlusion. Successful occlusion often allows the patient to resume oral intake, improving nutritional status and facilitating early surgical intervention. ⑶ If the skin around the fistula is eroded, zinc oxide ointment can be applied to protect the skin and prevent further erosion by gastrointestinal contents.
4. Surgical treatment: ⑴ Indications: (1) The fistula persists for a long time despite the above measures or the fistula tract has become epithelialized. (2) Lip fistula. (3) Small intestinal fistula with a daily output >5000 ml despite the above measures. (4) Obstruction distal to the fistula. ⑵ Timing of surgery: (1) Intra-abdominal infection is localized or controlled. (2) The patient’s overall nutritional status is good. (3) Generally, fistulas persisting for more than 3 months. However, for high-output small intestinal fistulas, surgery should be performed as early as possible after inflammation control and nutritional improvement. ⑶ Surgical methods: Commonly used procedures include: (1) Intestinal resection and anastomosis: Suitable for early small intestinal fistulas with mild intra-abdominal infection. (2) Fistula bypass: The affected intestinal segment is bypassed, and the proximal and distal ends of the small intestine are anastomosed to restore continuity. Suitable for small intestinal and colonic fistulas. (3) Vascularized intestinal seromuscular patch repair: Suitable for fistulas in difficult-to-resect segments, such as duodenal fistulas.
5. Prevention and treatment of complications: Strict monitoring of cardiac and pulmonary function, as well as blood electrolytes, is essential. Prompt treatment is required for complications such as septic shock, massive gastrointestinal bleeding, and respiratory failure.