What is the evaluation and management of a peritoneal dialysis (PD) catheter malfunction when flushing is not possible?

Evaluation and Management of PD Catheter Malfunction with Inability to Flush

When a peritoneal dialysis (PD) catheter cannot be flushed, prompt radiographic evaluation and intervention are necessary to diagnose the cause and restore catheter function to prevent complications and potential need for catheter replacement. 1

Initial Assessment

Causes of PD Catheter Malfunction

• Mechanical obstruction:
  • Catheter tip malposition
  • Fibrin sheath formation
  • Omental wrapping
  • Intraluminal thrombus
  • External compression
• Technical issues:
  • Kinking of the catheter
  • Tubing connection problems

Immediate Evaluation

1. Assess catheter age:

   • Recently placed catheters: More likely mechanical obstruction or improper placement 1
   • Older catheters: More likely fibrin sheath or omental wrapping

2. Physical examination:

   • Check for kinks in external portion of catheter
   • Assess exit site for signs of infection
   • Examine abdomen for tenderness suggesting peritonitis

Management Algorithm

Step 1: Basic Troubleshooting

• Reposition patient (try supine, lateral positions)
• Check for kinks in external tubing
• Ensure all connections are secure

Step 2: If Basic Measures Fail

• Radiographic evaluation is mandatory to diagnose the cause of dysfunction 1
• Catheter imaging with contrast infusion can identify:
  • Malpositioned catheter tip
  • Residual lumen thrombus
  • External fibrin catheter sheath 1

Step 3: Interventions Based on Radiographic Findings

1. For catheter malposition:

   • Repositioning of the catheter under fluoroscopic guidance 1

2. For fibrin sheath or intraluminal thrombus:

   • Intraluminal thrombolytic therapy:
     • Use tissue plasminogen activator (tPA) as an interdialytic lock between dialysis treatments 1
     • For severe occlusion: Higher-dose lytic infusion may be required 1

3. For persistent obstruction:

   • Specialized catheter brush may be used to mechanically remove thrombus from conventional catheter lumens 1
   • Angioplasty of the vessel if indicated 1

4. For irreparable obstruction:

   • Catheter replacement over guidewire if malpositioned 1
   • Complete catheter replacement via original wound or new mini-laparotomy 2

Outcomes and Follow-up

Success Rates

• Catheter revision and replacement procedures by nephrologists show:
  • 71.6% catheter survival at 1 month
  • 48.4% catheter survival at 6 months 2

Monitoring After Intervention

• Monitor for complications:
  • Bleeding requiring surgical exploration (rare)
  • Wound infection
  • Peritonitis within 4 weeks after surgery 2

Indications for Switching to Hemodialysis

If PD catheter dysfunction cannot be resolved, consider transfer to hemodialysis when:

• Technical/mechanical defects are irreparable 1
• Inadequate solute transport or fluid removal persists despite interventions 1
• Patient develops unacceptably frequent peritonitis 1

Prevention Strategies

• Regular assessment of catheter performance is essential 1
• Proper catheter placement and fixation can prevent displacement 3
• Some centers perform routine flushing of PD catheters during periods of rest, though practices vary widely and evidence for optimal protocols is lacking 4, 5

Important Considerations

• Early intervention for catheter dysfunction is critical as a dysfunctional catheter is easier to salvage than a nonfunctional one 1
• Prompt treatment reduces inadequate dialysis complications 1
• PD catheter revision and replacement by nephrologists has acceptable outcomes and reasonable complication rates 2
• Vascular access planning should be considered if PD failure is likely, as recommended by guidelines 1