Citrate versus heparin lock for prevention of hemodialysis catheter-related complications: updated systematic review and meta-analysis of randomized controlled trials

Objective To provide updated evidence, we conducted a systematic review and meta-analysis to compare citrate lock with heparin in the prevention of hemodialysis catheter-related complications. Methods A systematic review and meta-analysis of randomized controlled trials were obtained by searching PubMed, EMBASE, Ovid, Cochrane library, and the Web of Science databases. Primary outcomes were catheter-related bloodstream infections (CRBI), exit-site infections, bleeding events, catheter removal for poor flow, and thrombolytic treatment. Secondary outcomes were thrombocytopenia, access-related admission, and all-cause mortality. Results The meta-analysis showed that the citrate lock containing antimicrobials can reduce the risk of CRBI when compared with heparin lock (RR: 0.34, 95% CI 0.24-0.49; I-2 = 0%; P<0.00001), and a tunneled cuffed catheter (TCC) was more beneficial for the prevention of CRBI (RR: 0.42, 95% CI 0.25-0.69; I-2 = 40%; P = 0.0007) when compared with non-tunneled cuffed catheters (NTCC). The microbiological correlation analysis suggests that the occurrence of CRBI is closely related to S. aureus in catheters locked by citrate (P = 0.015) rather than by heparin (P = 0.868). In the analysis of exit-site infection, citrate lock with NTCC was more effective in preventing exit-site infection than heparin (RR: 0.48, 95% CI 0.31-0.75; I-2 = 0%; P = 0.001). In addition, the risk of bleeding episodes was reduced in hemodialysis patients using citrate lock with TCC (RR: 0.53, 95% CI 0.32-0.86; I-2 = 0%; P = 0.01) and patients with citrate alone (RR: 0.51, 95% CI 0.30-0.85; I-2 = 12%; P = 0.010). The risk of catheter removal for poor flow (P = 0.91), thrombolytic treatment (P = 0.76), thrombocytopenia (P = 0.37), access-related admission (P = 0.10), and all-cause mortality (P = 0.62) was not significantly different. Conclusions Antimicrobial-containing citrate lock solutions could reduce the risk of CRBI in hemodialysis patients. The occurrence of CRBI is closely related to S. aureus in catheters locked by citrate rather than by heparin. Citrate lock was effective in reducing exit-site infection in NTCC and bleeding events in TCC.