What is an enteric fistula and could green drainage from a Jackson‑Pratt drain after ventral or incisional hernia repair with mesh indicate its presence?

What is an Enteric Fistula and Its Relevance to Green Drainage After Hernia Repair

An enteric fistula is an abnormal communication between the intestinal tract and another structure—either another organ, the skin (enterocutaneous), or the atmosphere—and green drainage from a Jackson-Pratt drain after ventral or incisional hernia repair with mesh strongly suggests this serious complication, particularly an enterocutaneous fistula. 1, 2

Definition and Types

An enteric fistula represents any pathological connection originating from the bowel. 2 The most relevant types in the context of hernia repair include:

• Enterocutaneous fistula: Communication between bowel and skin or external atmosphere, which is the most likely diagnosis when green (bilious or enteric) drainage appears in a surgical drain 1, 2
• Enteroenteric fistula: Connection between bowel segments, often asymptomatic 1
• Enterovesical fistula: Connection to the bladder 1

Clinical Significance of Green Drainage Post-Hernia Repair

Green drainage from a Jackson-Pratt drain after ventral or incisional hernia repair with mesh placement is highly suspicious for an enterocutaneous fistula and represents a surgical emergency requiring immediate evaluation. 3, 4, 5

The green color indicates enteric content (bile, succus entericus, or intestinal secretions) communicating with the surgical site. 2 This complication, while rare, is serious and can occur:

• Early: Within days to weeks postoperatively due to unrecognized bowel injury, inadequate source control, or technical complications 1, 2
• Late: Months to years after repair (reported cases at 6-10 years) due to mesh erosion into bowel 3, 4, 5

Pathophysiology in Mesh-Related Hernias

Mesh-related enterocutaneous fistulas develop through several mechanisms:

• Direct mesh-bowel contact: Synthetic mesh placed intraperitoneally or in direct contact with bowel loops can erode into the intestinal lumen over time 3, 4, 5
• Mesh migration: Gradual displacement of mesh toward and into adjacent bowel 4
• Chronic inflammation and adhesions: Leading to pressure necrosis and eventual perforation 3, 5
• Infection: Mesh infection can progress to involve adjacent bowel, creating fistulous communication 1, 3

Immediate Diagnostic and Management Algorithm

Step 1: Confirm Enteric Content

• Analyze drain fluid: Green/bilious appearance, elevated bilirubin, or presence of enteric enzymes confirms intestinal origin 2
• Assess drain output volume: High-output fistulas (>500 mL/day) indicate more proximal bowel involvement and greater nutritional risk 1, 2

Step 2: Rule Out Sepsis and Abscess

• Evaluate for systemic inflammatory response: Fever, tachycardia, leukocytosis suggest associated intra-abdominal abscess requiring urgent drainage 1
• Obtain CT imaging with contrast: Essential to identify abscess collections, define fistula anatomy, assess for bowel obstruction, and evaluate mesh position 1, 2
• Drain any identified collections: Radiological or surgical drainage is mandatory before definitive management 1

Step 3: Optimize Patient Status (Sepsis-Nutrition-Anatomy Framework)

The management of enterocutaneous fistula requires addressing three key factors:

• Control sepsis: Aggressive drainage of abscesses, appropriate antimicrobials, and source control 1, 2
• Optimize nutrition: High-output fistulas cause massive protein and electrolyte losses; enteral feeding is preferred when tolerated, otherwise parenteral nutrition is essential 1, 2
• Define anatomy: Fistulography or CT fistulography to map the tract, identify distal obstruction, and plan surgical approach 1, 2

Step 4: Definitive Management Strategy

Complete mesh excision with bowel resection and repair is required for mesh-related enterocutaneous fistulas, as partial mesh removal results in 29% fistula recurrence versus 6% with complete excision. 6

• Timing: Definitive surgery should be delayed 3-6 months after initial presentation to allow inflammation to resolve, nutritional optimization, and wound healing 1, 2
• Surgical approach: Requires complete excision of involved mesh, resection of fistulous bowel segment, and primary anastomosis 1, 6
• Hernia repair: Simultaneous ventral hernia repair with non-bridged biological mesh (acellular porcine dermal matrix) results in 26% recurrence versus 66% with suture repair alone 6
• Avoid synthetic mesh: In contaminated fields with bowel resection, biological mesh or primary repair is preferred 1, 6

Critical Pitfalls to Avoid

• Do not attempt conservative management: Mesh-related enterocutaneous fistulas do not close spontaneously and require surgical intervention 6
• Do not perform partial mesh excision: Leaving any mesh in contact with the fistula tract increases recurrence risk nearly 5-fold 6
• Do not rush to surgery: Premature operation before nutritional optimization and sepsis control leads to failure and increased mortality 1, 2
• Do not ignore associated complications: Luminal strictures, multiple fistula tracts, and frozen abdomen significantly complicate management and must be identified preoperatively 1

Prevention Strategies

To minimize risk of enterocutaneous fistula in hernia repair:

• Avoid direct mesh-bowel contact: Use preperitoneal or retrorectus mesh placement rather than intraperitoneal onlay 4, 5
• Cover exposed bowel: Use omentum, peritoneum, or barrier materials when intraperitoneal mesh is necessary 1
• Ensure adequate bowel coverage: Deep burying of intestinal anastomoses under bowel loops prevents direct mesh contact 1
• Recognize high-risk scenarios: Emergency repair, contaminated fields, bowel resection, and poor tissue quality increase fistula risk 1