title: Effect of ultra-low dose and standard heparin locks on early tunnelled dialysis catheter outcomes in low-risk dialysis patients.
abstract: OBJECTIVE
  Initial heparin locks instilled after tunnelled dialysis catheter (TDC) insertion can leak causing systemic anticoagulation and also promote staphyloccocal biofilm formation, predisposing to catheter-related infection (CRI). The 1000 U/mL concentration is thus advocated as the optimal dose for preventing catheter bleeding and malfunction. The effect of lower heparin concentrations on further lowering these complications is not known. We compared early TDC outcomes between a non-standard ultra-low (500 U/mL) and standard initial heparin locks (1000 and 5000 U/mL).
  
  
  METHODS
  This was a retrospective study on prospectively collected data on 238 de novo internal jugular TDCs placed by nephrologists. Cases were categorized into groups 1, 2 and 3, according to initial heparin lock: 500 [n = 30], 1000 [n = 180] and 5000 U/mL [n = 28] respectively. Bleeding and malfunction within 24 h of TDC insertion, 30 days CRI-free catheter survival and the effects of clinical and laboratory factors on bleeding were evaluated.
  
  
  RESULTS
  Bleeding events were similar in groups 1, 2 and 3 (7 vs 14 vs 13%, respectively, P = 0.61). Malfunction was only seen in group 2 (3.3%). Thirty-day CRI-free catheter survival was comparable (96 vs 98 vs 97%, respectively, P = 0.22), giving a cumulative CRI rate of 0.76/1000 catheter days. All CRIs were staphylococcal. Univariate analysis did not reveal any significant predictors of catheter bleeding.
  
  
  CONCLUSIONS
  Immediate TDC bleeding, malfunction and CRI rate are not influenced by heparin lock concentrations ≤5000 U/mL in this low-risk cohort. However this needs to be corroborated in higher risk patients.
authors.affiliation: Renal Division, Department of Medicine, Khoo Teck Puat Hospital, Singapore.
authors.forename: Claude J
authors.initials: CJ
authors.lastname: Renaud
authors.forename: Eng Kuang
authors.initials: EK
authors.lastname: Lim
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Tho
authors.forename: Lee Ying
authors.initials: LY
authors.lastname: Yeoh
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D061807:Catheter Obstruction / Q000209:etiology; D055499:Catheter-Related Infections / Q000382:microbiology; D002405:Catheterization, Central Venous / Q000009:adverse effects / Q000295:instrumentation*; D002408:Catheters, Indwelling; D018572:Disease-Free Survival; D004867:Equipment Design; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D006493:Heparin / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects / Q000295:instrumentation*; D012189:Retrospective Studies; D012307:Risk Factors; D012846:Singapore; D013210:Staphylococcus / Q000302:isolation & purification; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D006493:Heparin
keywords: bleeding; catheter lock; hemodialysis; heparin; heparin leak; tunnelled dialysis catheter