What are the indications and considerations for using a PTFE (Polytetrafluoroethylene) graft in vascular surgery?

Indications and Considerations for PTFE Grafts in Vascular Surgery

PTFE (polytetrafluoroethylene) grafts should be used as the second-line option for vascular access after arteriovenous fistulas have been ruled out or have failed, particularly in hemodialysis patients who need reliable vascular access. 1

Primary Indications for PTFE Grafts

• When native arteriovenous fistulas cannot be established due to:

  • Inadequate vessel quality or size
  • Failed previous fistula attempts
  • Need for more immediate access (compared to fistula maturation time)
  • As a "planned bridge" to a future fistula 1

• Specific clinical scenarios where PTFE grafts are preferred:

  • Patients requiring rapid access for hemodialysis (PTFE grafts mature faster)
  • Patients with poor peripheral vessels unsuitable for fistula creation
  • Patients with limited life expectancy where fistula maturation time is impractical
  • When previous fistula attempts have failed 1

Advantages of PTFE Grafts

• Large surface area available for cannulation
• Technically easier to cannulate compared to fistulas
• Shorter maturation time (14 days minimum, ideally 3-6 weeks)
• Multiple insertion sites available
• Variety of shapes and configurations for placement flexibility
• Easier surgical handling and anastomosis construction
• Comparatively easier to repair surgically or endovascularly 1

Placement Considerations

• Preferred configurations:

  • Antecubital loop graft
  • Upper-arm curved graft 1

• Arterial inflow sites options:

  • Radial artery at the wrist
  • Brachial artery in the antecubital fossa
  • Brachial artery in lower portion of arm
  • Brachial artery below axilla
  • Axillary artery
  • Femoral artery (less preferred due to infection risk) 1

• Venous outflow site options:

  • Median antecubital vein
  • Proximal and distal cephalic vein
  • Basilic vein at elbow level
  • Basilic vein at upper arm level
  • Axillary vein
  • Jugular vein
  • Femoral vein 1

Material Selection and Modifications

• Standard wall 6-mm PTFE remains the gold standard for vascular grafts 1

• No convincing evidence supports one PTFE modification over another:

  • Tapered vs. uniform tubes
  • Externally supported vs. unsupported grafts
  • Thick vs. thin-walled configurations
  • Elastic vs. nonelastic material 1

• Early cannulation grafts (composite/PU grafts) may be considered as a catheter-sparing strategy 1

Important Clinical Considerations

• Expected lifespan: PTFE grafts typically last 3-5 years 1

• Maturation time: Minimum 14 days before cannulation, ideally 3-6 weeks to allow for tissue incorporation 1

• Vessel preservation strategy: Consider using smaller, more peripheral vessels for graft placement to preserve proximal sites for future access creation, despite potentially higher thrombosis risk 1

• Avoid proximal vessel temptation: Resist using larger proximal vessels despite better initial flow and patency, as this limits future access options 1

• Infection risk: PTFE has lower risk of disintegration with infection compared to biological grafts 1

• Thrombosis risk: Most common complication with PTFE grafts; requires careful monitoring and prompt intervention 2

Common Pitfalls to Avoid

• Placing grafts in proximal vessels first, which limits future access options
• Cannulating too early (before 14 days), increasing risk of complications
• Neglecting regular surveillance for stenosis or thrombosis
• Failing to consider PTFE grafts as a "bridge" to future fistula creation
• Using femoral placement without careful consideration of potential complications for future kidney transplantation 1

Monitoring and Complications

• Regular surveillance is essential to detect dysfunction before thrombosis
• Most common complications include:
  • Thrombosis (most frequent)
  • Infection (less common than with catheters)
  • Steal syndrome
  • Pseudoaneurysm formation
  • Venous stenosis 1, 2

By following these guidelines for PTFE graft placement and management, vascular access can be optimized to support effective hemodialysis while preserving future access options.