title: Citrate versus heparin lock for hemodialysis catheters: a systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Citrate solution has been suggested as an effective and safe catheter lock in hemodialysis. However, whether a citrate lock is superior to a heparin lock in preventing catheter-related infections and maintaining catheter patency is inconclusive.
  
  
  METHODS
  A systematic review and meta-analysis was performed by searching in PubMed, EMBASE, Ovid, the Cochrane Library, and Web of Science databases and major nephrology journals.
  
  
  METHODS
  Patients receiving hemodialysis with central venous catheters.
  
  
  METHODS
  Randomized controlled trials comparing citrate locks with heparin locks in hemodialysis patients with central venous catheters.
  
  
  METHODS
  Locking central venous catheters with citrate locks.
  
  
  RESULTS
  Primary outcomes include catheter-related bloodstream infection (CRBSI), exit-site infection, catheter removal for poor flow, and thrombolytic treatment.
  
  
  RESULTS
  13 randomized controlled trials (1,770 patients, 221,064 catheter-days) met the inclusion criteria. Pooled analyses found that citrate locks could significantly reduce the incidence of CRBSI (risk ratio [RR], 0.39; 95% CI, 0.27-0.56; P < 0.001). Subgroup analysis showed that antimicrobial-containing citrate locks (citrate + gentamicin, citrate + taurolidine, and citrate + methylene blue + methylparaben + propylparaben) were superior to heparin locks in the prevention of CRBSI (P < 0.001, P = 0.003, and P = 0.008, respectively), whereas citrate alone failed to show a similar advantage (P = 0.2). Low- (1.04%-4%) to moderate-concentration (4.6%-7%) citrate locks were associated with decreased CRBSI incidence (P < 0.001 and P = 0.003, respectively), but patients receiving high-concentration (30%-46.7%) citrate and heparin locks had similar incidences (P = 0.3). The incidence of bleeding episodes (RR, 0.48; 95% CI, 0.30-0.76; P = 0.002) was significantly lower in patients receiving citrate locks, whereas both groups were similar in terms of exit-site infection (P = 0.2), catheter removal for poor flow (P = 0.9), thrombolytic treatment (P = 0.8), all-cause death (P = 0.3), catheter thrombosis (P = 0.9), mean catheter duration (P = 0.2), CRBSI-free catheter survival (P = 0.2), and catheter-related readmission (P = 0.5).
  
  
  CONCLUSIONS
  All studies used in the meta-analysis were performed in Western countries. The applicability of our findings to other regions remains to be clarified.
  
  
  CONCLUSIONS
  An antimicrobial-containing citrate lock is better than a heparin lock in the prevention of catheter-related infection, while citrate alone fails to show a similar advantage. Citrate locks of low to moderate concentrations, rather than high concentration, were superior to heparin locks in preventing CRBSI. Citrate locks also might decrease bleeding episodes. No difference has been identified in the efficacy to prevent exit-site infection or preserve catheter patency between citrate and heparin locks.
authors.affiliation: Division of Nephrology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Division of Nephrology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: West China School of Medicine, Sichuan University, Chengdu, China.
authors.forename: Jiqiao
authors.initials: J
authors.lastname: Yang
authors.affiliation: Division of Nephrology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Division of Nephrology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Division of Nephrology, West China Hospital, Sichuan University, Chengdu, China. Electronic address: fupinghx@163.com.
authors.forename: Ping
authors.initials: P
authors.lastname: Fu
mesh_terms: D000925:Anticoagulants / Q000494:pharmacology; D055499:Catheter-Related Infections / Q000517:prevention & control*; D062905:Central Venous Catheters / Q000592:standards*; D019343:Citric Acid / Q000494:pharmacology*; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D006435:Renal Dialysis / Q000379:methods*; D013927:Thrombosis / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D019343:Citric Acid; D006493:Heparin
keywords: Hemodialysis; antimicrobial solution; catheter lock; catheter-related bacteremia; citrate; exit-site infection; heparin; lock solution; renal replacement therapy; vascular access