Citrate anticoagulation using ACD solution A during long-term haemodialysis

Haemodialysis with regional citrate anticoagulation in patients with contraindications for heparin is increasingly performed in the USA and Europe. Most published protocols use trisodium citrate, which is not readily available nor is it licensed in Australia. We established a protocol for citrate-anticoagulation in haemodialysis using acid citrate dextrose solution A (ACDA), which is approved for apheresis procedures in Australia. The aim of the present study was to assess the safety and efficacy of this protocol for routine use in haemodialysis patients.

Systemic and post-filter blood ionized calcium, serum sodium and bicarbonate and dialyzer clotting score were analyzed prospectively in 14 patients undergoing 150 consecutive haemodialysis treatments with citrate anticoagulation using calcium-free dialysate. A simple algorithm allowed the attending nurse to adjust citrate infusion (to maintain post-filter ionized calcium at 0.2-0.3 mmol/L) and i.v. calcium substitution. Scheduled dialysis time was 4 h, and point-of-care monitoring of blood ionized calcium during dialysis was done at 0, 15, 60, 120 and 240 min.

ACDA infusion rates of 300 mL/h were used in the first 52 treatments, but resulted in high dialyzer clotting score and 6% of treatments were discontinued due to complete clotting. Thereafter, ACDA infusion rate was increased to 350 mL/h, with all 98 subsequent treatments completed successfully. Ionized calcium levels were stable during all procedures with post-dialysis serum sodium averaging 135 ± 3 mmol/L and bicarbonate 23.8 ± 2 mmol/L.

Routine use of citrate anticoagulation in the setting of a long-term haemodialysis unit is safe and efficient. Point-of-care measurements of ionized calcium levels are critical to safely and successfully perform citrate anticoagulation.