Gastrointestinal stenting

Gastrointestinal stenting by an interventional radiologist is a minimally invasive procedure used to relieve obstructions or strictures within the gastrointestinal (GI) tract by inserting a stent, a flexible tube-like device, to restore normal flow and function. 

Indications

1. GI Obstruction: Stenting is used to relieve obstructions caused by tumours (e.g., colorectal cancer), strictures, or other conditions that impede the normal passage of food, liquids, or waste through the GI tract.
2. Palliative Care: Stenting may be performed in palliative settings to alleviate symptoms such as pain, nausea, vomiting, or difficulty swallowing in patients with advanced GI malignancies or non-resectable lesions.
3. Bridge to Surgery: In some cases, stenting can serve as a temporary measure to improve nutritional status and prepare patients for surgical intervention.

Pre-procedure Preparation

1. Patient Assessment:
   • Comprehensive evaluation of the patient’s medical history, symptoms, underlying GI condition, imaging studies (CT scans, endoscopy), and nutritional status.
   • Assessment of coagulation profile, renal function, and any contraindications to the procedure.
2. Imaging and Planning:
   • CT scans, MRI, or fluoroscopic imaging are used to identify the location, extent, and nature of the GI obstruction or stricture.
   • Three-dimensional reconstructions aid in planning the stenting procedure, including stent size and placement.
3. Informed Consent:
   • Explanation of the procedure, its purpose, potential risks (such as perforation, migration of the stent, bleeding, or infection), benefits, and alternatives. Informed consent is obtained.

Procedure Steps

1. Patient Positioning:
   • The patient is typically positioned on the procedure table, lying flat on their back or in a comfortable position based on the target area for stent placement.
2. Local Anesthesia:
   • Local anaesthesia may be administered at the site of stent insertion, such as the mouth (for esophageal stenting) or the perianal region (for colonic stenting), to numb the area and reduce discomfort.
3. Endoscopic or Fluoroscopic Guidance:
   • Depending on the location of the obstruction, either endoscopic or fluoroscopic guidance is used to visualise the GI tract and guide the stent placement.
   • Endoscopy is commonly used for esophageal or upper GI stenting, while fluoroscopy is used for colonic or lower GI stenting.
4. Stent Insertion:

   

   • A specialised catheter or endoscope with a stent delivery system is advanced through the GI tract to the site of obstruction or stricture.
   • The stent, typically made of metal (e.g., nitinol) or plastic, is deployed at the targeted location to open up the narrowed or blocked area and restore patency.
5. Stent Expansion:
   • Once deployed, the stent expands to its full diameter, creating a stable conduit for the passage of food, liquids, or waste through the GI tract.
   • The stent is designed to be flexible and conform to the natural contours of the GI tract, minimising discomfort and maintaining functionality.
6. Confirmation:
   • Imaging studies (fluoroscopy or endoscopy) are performed post-stent placement to confirm proper positioning, expansion, and patency of the stent.
   • Contrast dye may be injected to assess flow through the stent and ensure adequate relief of the obstruction.
7. Post-procedure Care:

• • The patient is monitored for a period after the procedure to assess for any immediate complications, such as perforation, bleeding, or stent migration.
  • Pain management, nutritional support, and follow-up care instructions are provided based on the patient’s needs and the type of stent placed.

Benefits of GI Stenting

• Immediate Symptom Relief: Rapid relief of symptoms such as dysphagia (difficulty swallowing), abdominal pain, nausea, vomiting, or constipation caused by GI obstruction.
• Minimally Invasive: Compared to surgical interventions, stenting is minimally invasive, with shorter recovery times, reduced hospital stays, and lower risk of complications.
• Improved Quality of Life: Enhances patient comfort, nutritional intake, and overall quality of life by restoring normal GI function and allowing for oral intake.
• Palliative Care: Provides palliative relief in patients with advanced GI malignancies or non-resectable lesions, improving comfort and easing symptoms.

Risks and Considerations

• Perforation: Risk of perforation or injury to the GI tract during stent placement, especially in cases of friable or fragile tissue.
• Migration: Stent migration (partial or complete displacement) can occur, requiring repositioning or additional interventions.
• Stent-related Complications: Potential risks include stent occlusion (due to tumour ingrowth or overgrowth), stent fracture, bleeding, infection, or tissue ingrowth.
• Re-stenosis: In some cases, stent patency may be compromised over time due to tumour progression, tissue ingrowth, or stent-related factors, necessitating repeat interventions.

Conclusion

Gastrointestinal stenting by an interventional radiologist is a valuable minimally invasive technique for treating GI obstructions or strictures. It offers rapid symptom relief, improved quality of life, and is well-suited for palliative care or as a bridge to surgical intervention. Close monitoring, patient education, and follow-up care are essential to optimise outcomes and address any potential complications or concerns.