Overview

Definition:
-A gastrocutaneous fistula is an abnormal opening between the stomach and the skin, allowing gastric contents to leak externally
-After percutaneous endoscopic gastrostomy (PEG) placement, a gastrocutaneous fistula refers to persistent leakage or an unintended opening at the PEG site that fails to close spontaneously after device removal or discontinuation.
Epidemiology:
-The incidence of persistent gastrocutaneous fistulas after PEG removal is relatively low, generally reported between 1-3%
-Risk factors include malnutrition, immunosuppression, prolonged PEG use, and complications at the insertion site such as infection or irritation.
Clinical Significance:
-Persistent gastrocutaneous fistulas can lead to significant morbidity, including malnutrition due to leakage of gastric contents, skin breakdown and infection, electrolyte imbalances, and psychological distress for the patient
-Prompt and effective management is crucial for patient recovery and quality of life.

Clinical Presentation

Symptoms:
-Persistent leakage of gastric fluid or bile from the PEG site after device removal
-Skin irritation, maceration, and erythema around the stoma
-Foul odor from the drainage
-Inability to initiate oral feeding due to persistent leakage
-Signs of dehydration or malnutrition in severe cases.
Signs:
-Visible stoma opening at the gastrostomy site
-Continuous drainage of gastric contents onto dressings
-Evidence of cellulitis or abscess formation around the stoma
-Palpable induration or granulation tissue at the fistula tract
-Poor wound healing.
Diagnostic Criteria:
-Diagnosis is primarily clinical, based on the persistent drainage of gastric contents from the stoma site for more than 2-3 weeks after PEG removal or discontinuation
-Confirmation may involve a contrast study of the fistula tract to assess its size and depth, or endoscopic evaluation.

Diagnostic Approach

History Taking:
-Detailed history of PEG placement, duration of use, and any complications during its indwelling period
-Previous attempts at closure
-Nutritional status and oral intake capabilities
-Co-morbidities, especially those affecting wound healing or immune function
-Any signs of infection or systemic illness.
Physical Examination:
-Careful inspection of the stoma site for erythema, edema, induration, and discharge
-Assess the surrounding skin for maceration or breakdown
-Palpate the tract for any tenderness or induration
-Evaluate the patient for signs of dehydration or malnutrition.
Investigations:
-Contrast fistulography: A contrast medium is injected into the fistula tract and serial X-rays are taken to delineate the tract's course, size, and communication with the stomach
-Endoscopy: Can visualize the gastrocutaneous opening from the gastric side and assess the integrity of the gastric mucosa
-Laboratory tests: Complete blood count (CBC) to assess for infection, electrolytes, albumin to assess nutritional status.
Differential Diagnosis:
-Simple wound dehiscence at the stoma site without persistent fistula formation
-Skin breakdown due to gastric acid irritation without a true tract
-Enterocutaneous fistula from other abdominal pathology
-Abscess or cellulitis at the PEG site.

Management

Initial Management:
-Conservative management is the first-line approach
-Meticulous wound care with frequent dressing changes
-Application of barrier creams or ostomy pastes to protect the surrounding skin from gastric secretions
-Nutritional support optimization, either via parenteral nutrition or if possible, through an alternative oral or enteral route
-Identification and treatment of any superimposed infection.
Medical Management:
-Proton pump inhibitors (PPIs) may be used to reduce gastric acidity, potentially aiding in spontaneous closure
-Antibiotics are indicated if there is evidence of local infection or cellulitis
-Nutritional support should be optimized.
Surgical Management:
-Surgical intervention is considered for persistent fistulas that do not close with conservative measures, typically after 4-8 weeks of conservative therapy
-Options include: Simple Ligation and Excision: For small, superficial fistulas
-Fistula Excision with Gastric and Cutaneous Closure: The fistula tract is dissected and excised, followed by layered closure of the gastric wall and the abdominal wall defect
-Gastric Resection: In cases of large or complex fistulas involving significant gastric wall defect, a partial gastrectomy may be necessary
-Minimally Invasive Techniques: Laparoscopic approaches may be used for fistula excision and closure in select cases.
Supportive Care:
-Pain management
-Regular monitoring for signs of infection
-Psychological support for the patient
-Close follow-up by a multidisciplinary team including surgeons, gastroenterologists, dietitians, and stoma nurses.

Complications

Early Complications:
-Worsening skin breakdown
-Cellulitis or abscess formation at the stoma site
-Dehydration and electrolyte disturbances due to persistent leakage
-Increased risk of malnutrition.
Late Complications:
-Scarring and cosmetic deformity
-Adhesions if laparotomy is performed
-Recurrence of the fistula after attempted closure
-Chronic skin irritation or dermatitis.
Prevention Strategies:
-Proper PEG insertion technique and fixation
-Regular stoma site care and monitoring
-Prompt management of any early complications like infection or irritation
-Adequate nutritional support during and after PEG use
-Judicious use of PEG, considering alternative feeding methods when appropriate.

Prognosis

Factors Affecting Prognosis:
-Size and depth of the fistula
-Duration of leakage
-Patient's nutritional status and immune function
-Presence of comorbidities
-Success of initial management strategies
-Extent of surgical intervention required.
Outcomes:
-Most small gastrocutaneous fistulas after PEG will close spontaneously with conservative management
-Larger or persistent fistulas requiring surgical intervention generally have good outcomes with complete closure, although recurrence is possible
-Patients with underlying severe malnutrition or immunosuppression may have poorer outcomes.
Follow Up:
-Close follow-up is essential to monitor for signs of recurrence or complications
-This typically includes regular clinical assessments, wound checks, and nutritional status evaluation
-For surgically managed fistulas, follow-up continues until complete wound healing and functional recovery.

Key Points

Exam Focus:
-Recognize the common presentation of a persistent gastrocutaneous fistula post-PEG
-Understand the indications for conservative vs
-surgical management
-Be familiar with the surgical techniques for fistula closure and their potential complications.
Clinical Pearls:
-Always consider conservative management first for post-PEG fistulas, focusing on meticulous wound care and nutritional support
-Contrast fistulography is a key investigation to delineate the tract
-Surgical excision and layered closure is the definitive treatment for refractory fistulas.
Common Mistakes:
-Prematurely opting for surgery without adequate conservative trial
-Underestimating the importance of skin care and nutritional support
-Inadequate assessment of fistula tract size and depth
-Failing to identify and manage underlying factors contributing to poor wound healing.