Application of regional citrate anticoagulation in patients at high risk of bleeding during intermittent hemodialysis: a prospective multicenter randomized controlled trial

Objective: Safe and effective anticoagulation is essential for hemodialysis patients who are at high risk of bleeding. The purpose of this trial is to evaluate the effectiveness and safety of two-stage regional citrate anticoagulation (RCA) combined with sequential anticoagulation and standard calcium-containing dialysate in intermittent hemodialysis (IHD) treatment. Methods: Patients at high risk of bleeding who underwent IHD from September 2019 to May 2021 were prospectively enrolled in 13 blood purification centers of nephrology departments, and were randomly divided into RCA group and saline flushing group. In the RCA group, 0.04 g/mL sodium citrate was infused from the start of the dialysis line during blood draining and at the venous expansion chamber. The sodium citrate was stopped after 3 h of dialysis, which was changed to sequential dialysis without anticoagulant. The hazard ratios for coagulation were according to baseline. Results: A total of 159 patients and 208 sessions were enrolled, including RCA group (80 patients, 110 sessions) and saline flushing group (79 patients, 98 sessions). The incidence of severe coagulation events of extracorporeal circulation in the RCA group was significantly lower than that in the saline flushing group (3.64% vs. 20.41%, P<0.001). The survival time of the filter pipeline in the RCA group was significantly longer than that in the saline flushing group ((238.34±9.33) min vs. (221.73±34.10) min, P<0.001). The urea clearance index (Kt/V) in the RCA group was similar to that in the saline flushing group with no statistically significant difference (1.12±0.34 vs. 1.08±0.34, P=0.41). Conclusions: Compared with saline flushing, the two-stage RCA combined with a sequential anticoagulation strategy significantly reduced extracorporeal circulation clotting events and prolonged the dialysis time without serious adverse events.