27 Citrate Anticoagulation for Single‐Needle Hemodialysis: Safety and Efficacy

Background  Single‐needle (SN) hemodialysis can be the only option for selected patients with difficulties with vascular access. Full heparinization is required to avoid clotting in the circuit. In patients at risk of bleeding, citrate could be the alternative anticoagulant. The aim of our retrospective clinical study was to evaluate safety and efficacy of regional citrate anticoagulation (RCA) during SN hemodialysis. Patients and methods  Regional citrate anticoagulation was performed using 4% trisodium citrate, 1 m CaCl 2 and dialysate with 0 mmol/L Ca, 0.5 mmol/L Mg and 0 g/L glucose, Na was set at 138 mmol/L and HCO 3 at 28 mmol/L. Safety was assessed by percent of procedures that were terminated prematurely or changed to another modality due to RCA‐related complications and by incidence of important hypocalcemia, defined as decrease of iCa from start of dialysis > 0.2 mmol/L or decrease > 0.05 mmol/L to a value of < 0.8 mmol/L. Efficacy was evaluated by visual assessing of clot formation in arterial and venous bubble traps and dialyzer, after completing dialysis, by scoring: grade 5 (<10 fibers clotted) to 0 (>20% fibers clotted). It was considered insufficient if the grade was ≤ 3 or a significant clot in bubble traps occurred. Results  In retrospective analysis of 41 protocols, important hypocalcemia was recorded in 34% of cases. 5% of procedures were terminated prematurely. Median dialyzer grade was 5 (interquartile range 4–5, N  = 36). Anticoagulation was insufficient in 17% (6/36) of procedures, in these cases neither citrate infusion rate was lower nor coagulation time shorter. None of the systems clotted. Thirty protocols were filled in completely; average parameters are shown in the table below. In the first hour iCa decreased in 67% of procedures for 0.08 ± 0.05 mmol/L, those procedures had significantly lower starting calcium rate (6.4 ± 0.9 vs. 7.3 ± 1.1 mmol/L, P  = 0.02) and higher starting iCa (1.02 ± 0.13 vs. 0.89 ± 0.14 mmol/L, P  = 0.02). Over the entire procedure iCa decreased in 80% of cases for 0.17 ± 0.09 mmol/L, there was significant but small increase in Na (135 ± 4 vs. 137 ± 4 mmol/L, P  ≤ 0.01) and no increase in HCO 3 at the end of hemodialysis ( Table A27). A27Parameter Valueblood flow (mL/min) 244 ± 27 starting rate of 4% Na citrate (mL/h) 191 ± 19 citrate rate (percent of mean blood flow) 2.6% ± 0.4% starting rate of 1 m CaCl 2 (mL/h) 6.7 ± 1.1Conclusions  Citrate anticoagulation during single‐needle hemodialysis is a safe and effective procedure in the majority of patients. CaCl 2 infusion rate should often be increased to correct hypocalcemia. Close monitoring of iCa is mandatory. Increased starting dose of CaCl 2 should be evaluated.