Citrate anticoagulation for single-needle hemodialysis: safety and efficacy

Single-needle hemodialysis can be the only option in some patients and requires full heparinization. The aim of our retrospective clinical study was to evaluate the safety and efficacy of regional citrate anticoagulation for single-needle hemodialysis. Citrate anticoagulation was performed during 41 single-needle hemodialysis procedures in 24 patients at risk of bleeding, using 4% trisodium citrate, 1 M CaCl2 and calcium-free dialysate. Safety was assessed by the percentage of procedures that were terminated prematurely or changed to another modality due to citrate-related complications and by incidence of important hypocalcemia. Efficacy was evaluated by visually assessing clot formation in the circuit. Five per cent of the procedures were terminated prematurely. Important hypocalcemia was recorded in 34% of the procedures. Anticoagulation was suboptimal in 17% of the procedures, but none of the systems clotted. The median dialyzer assessment grade was excellent. The average protocol parameters were: blood flow 244 +/- 27 mL/min, starting rate of citrate 191 +/- 19 mL/h, starting rate of calcium 6.7 +/- 1.1 mL/h. In the first hour, ionized calcium decreased in 67% of the procedures by 0.08 +/- 0.05 mmol/L. During the entire procedure, ionized calcium decreased in 80% of the cases by 0.17 +/- 0.09 mmol/L. There was a significant, but small increase in sodium (135 +/- 4 vs 137 +/- 4 mmol/L) and no increase in bicarbonate. Citrate anticoagulation during single-needle hemodialysis, according to our protocol, is safe and effective. Close monitoring of ionized calcium is mandatory. The calcium infusion rate should frequently be increased to correct hypocalcemia. The increased starting rate of calcium should be evaluated.