title: Catheter patency and function after catheter sheath disruption: a pilot study.
abstract: OBJECTIVE
  Hemodialysis catheters are frequently complicated by dysfunction from fibrin sheaths. Previous studies of sheath disruption have methodologic limitations but suggest that the patency after disruption is short.
  
  
  METHODS
  A randomized, controlled, pilot trial was conducted to investigate the impact of angioplasty sheath disruption on catheter patency and function. Forty-seven long-term hemodialysis patients with secondary, refractory catheter dysfunction underwent guidewire exchange to replace their catheters.
  
  
  RESULTS
  Sheaths were present in 33 (70%) of the 47 patients. In 18 patients who were randomly assigned to disruption, the median time to repeat dysfunction was 373 d compared with 97.5 d in patients who did not undergo disruption (P = 0.22), and the median time to repeat catheter exchange was 411 and 198 d, respectively (P = 0.17). Mean blood flow (340 versus 329 ml/min; P < 0.001) and urea reduction ratio (72 versus 66%; P < 0.001) were higher in the disruption group. Fourteen patients had no sheaths, and their median times to repeat dysfunction and repeat exchange were 849 and 879 d, respectively. Patients with no sheaths had higher urea reduction ratio (73 versus 66%; P < 0.001) and a lower percentage of inadequate hemodialysis treatments (9.8 versus 27%; P = 0.01) and treatments that required thrombolytics (1.8 versus 5.0%; P = 0.03) than patients with sheaths that were not disrupted.
  
  
  CONCLUSIONS
  Disrupting sheaths by angioplasty balloon results in durable catheter patency and modestly improves blood flow and clearance over the duration of catheter use.
authors.affiliation: Sunnybrook Health Sciences Centre, Room A239, 2075 Bayview Avenue, Toronto, Canada M4N 3M5. matthew.oliver@sunnybrook.ca
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Oliver
authors.forename: David C
authors.initials: DC
authors.lastname: Mendelssohn
authors.forename: Robert R
authors.initials: RR
authors.lastname: Quinn
authors.forename: Elizabeth P
authors.initials: EP
authors.lastname: Richardson
authors.forename: Deeraj K
authors.initials: DK
authors.lastname: Rajan
authors.forename: Robyn A
authors.initials: RA
authors.lastname: Pugash
authors.forename: Joyce A
authors.initials: JA
authors.lastname: Hiller
authors.forename: Alex J
authors.initials: AJ
authors.lastname: Kiss
authors.forename: Charmaine E
authors.initials: CE
authors.lastname: Lok
mesh_terms: D000368:Aged; D000800:Angioplasty, Balloon / Q000379:methods*; D002405:Catheterization, Central Venous / Q000295:instrumentation*; D002408:Catheters, Indwelling; D005260:Female; D006083:Graft Occlusion, Vascular / Q000628:therapy*; D006801:Humans; D008297:Male; D010865:Pilot Projects; D006435:Renal Dialysis / Q000009:adverse effects* / Q000295:instrumentation*