Modified regional citrate anticoagulation is optimal for hemodialysis in patients at high risk of bleeding: A prospective randomized study of three anticoagulation strategies

Background：The recommended regular saline flushing presents clinical ineffectiveness for patients at high risk of bleeding with heparin contraindication. Regional citrate anticoagulation (RCA) has been used in a Ca2+ containing dialysate with prefilter citrate in one arm (RCA-one). The anticoagulation effect was not realized, and up to 40% resulted in serious clotting in the venous expansion chamber. We innovatively transferred one-quarter of the TSC from the prefilter to the postfilter based on RCA-one, which is called RCA-two in this trial. The objective of this study was to compare the efficacy and safety of RCA-two with either saline flushing or RCA-one in HD patients with a high bleeding risk. Method：In this investigator-initiated, multicenter, placebo-controlled, prospective, randomized clinical trial, 52 patients (77 sessions) were randomized to the RCA-two and RCA-one group in part one trial, and 45 patients (64 sessions) were randomized to the RCA-two and Saline group in part two trial. Serious clotting events, adverse events and blood analyses were recorded. Results：The primary outcome, Serious clotting events in the RCA-two group were significantly lower than that in the RCA-one and Saline group (7.89% vs. 30.77%, P = 0.011; 3.03% vs. 54.84%, P < 0.001, respectively). The median circuit survival time was 240 min (IQR 240 to 240) in the RCA-two group, which was significantly longer than 230 min (IQR 155 to 240, P < 0.001) in the RCA-one group and 210 min (IQR 135 to 240，P = 0.003) in the Saline group. The majority of the AEs were hypotension, hypoglycemia and chest tightness, most of which were mild in intensity. Eight patients (20.51%) in the RCA-one group, 4 patients (12.90%) in the Saline group and 10 patients (26.31%) in the RCA-two group, P>0.05. Conclusions：Our data demonstrated that the modified anticoagulation protocol is more effective and feasible during hemodialysis therapy for patients at high risk of bleeding. Trial registration: GDREC, GDREC2017250H. Registered 2th February 2018-Retrospectively registered.