What is catheter fatigue?

What is Catheter Fatigue?

Catheter fatigue is not a formally recognized medical term in the provided clinical guidelines or literature. The evidence discusses related concepts including catheter failure, catheter dysfunction, and mechanical catheter complications, but does not define or use the specific term "catheter fatigue."

Related Concepts in the Literature

Catheter Failure

The closest analogous term is catheter failure, which has specific definitions depending on catheter type:

• Neuraxial catheters: Defined as the inability of the catheter to provide satisfactory analgesia, requiring replacement or alternative pain relief 1
• Hemodialysis catheters: Defined as failure to attain and maintain blood flow ≥300 mL/min at prepump arterial pressure more negative than -250 mmHg 1, 2

Catheter Dysfunction

Catheter dysfunction represents progressive deterioration in catheter performance 1, 2, 3:

• Blood flow rates <300 mL/min in hemodialysis catheters 2, 3
• Venous pressure >250 mmHg 3
• Progressive decrease in dialysis adequacy (URR <65% or Kt/V <1.2) 2, 3
• Inability to aspirate blood freely 2, 3

Mechanical Complications That May Resemble "Fatigue"

Material Degradation Over Time

Research demonstrates that catheter materials undergo mechanical changes with prolonged implantation 4:

• Silicone catheters: Show higher mechanical failure with increasing implantation time due to lower mechanical performance and loss of barium sulfate filler particles near the surface, creating microscopic notches that act as predetermined fracture sites 4
• Polyurethane catheters: More susceptible to chemical degradation from chemotherapeutic solutions but maintain better mechanical properties over time 4

Progressive Mechanical Problems

Several time-dependent mechanical issues occur 1:

• Fibrin sheath formation: Fibrin adheres to the external catheter surface with thrombus trapped between sheath and catheter tip 1, 3
• Catheter migration: Secondary malposition occurring when catheters dislocate due to increased thoracic pressure or physical activity 1
• Pinch-off syndrome: Compression of large-bore silicone catheters between the clavicle and first rib, leading to malfunction, obstruction, damage, or fracture 1

Clinical Implications

Timing of Dysfunction

The age of the catheter determines the likely cause of problems 1:

• New catheters (<2 weeks): Dysfunction typically results from mechanical obstruction, improper tip location, or catheter integrity problems 1
• Older catheters (≥2 weeks): Dysfunction more likely results from progressive occlusion by fibrin or thrombus 1, 3

Common Pitfalls

• Waiting until blood flow decreases to 300 mL/min may be too late to salvage the catheter and avoid loss of the access site 1
• A dysfunctional catheter is easier to salvage than a nonfunctional catheter, making early detection crucial 2, 3
• Catheter dysfunction leads to 17-33% of untimely catheter removals 2, 3