What factors influence your decision between guidewire exchange versus removal and replacement through a new tunnel tract for patients with tunneled hemodialysis catheter mechanical failure?

Mechanical failure of a tunneled dialysis catheter (TDC) could be from catheter cuff extrusion form the exit site, catheter thrombosis or a fibrin sheath. In all three scenarios I prefer guidewire exchange rather than removal and replacement of the TDC. Removal and replacement are much more invasive procedures for the patient and will often result in loss of that venous site for future TDC insertion. For a well-functioning TDC whose cuff has extruded, I do a simple catheter exchange over a guidewire. If there is catheter malfunction, defined as poor blood flow despite flushing with saline and instillation of TPA, such that the patient is getting inadequate dialysis, I check for a fibrin sheath before exchange. I pull the malfunctioning TDC ...