Toward Acid and Heparin-Free Dialysis: The Regional Anticoagulation Approach

Background and hypothesis In chronic intermittent hemodialysis, heparin is the standard anticoagulant as is the use of acid-containing dialysate. Regional anticoagulation (RA) with a calcium-free, citrate-containing dialysate has been developed. We compared RA using a calcium-free, citrate-free dialysate, routinely used in our centre, to systemic heparinization. Methods In a retrospective, observational, single-centre, cross-over study, we examined 15 patients undergoing chronic hemodialysis who were at high risk of bleeding and temporarily unable to use heparin. These patients received temporary treatment with RA involving calcium-free and citrate-free dialysate. We compared the dialysis session success rates during two distinct periods: standard heparinization and RA procedure with a calcium-free and citrate-free dialysate. Results In our study of 15 patients on chronic hemodialysis which compared 30 RA sessions to 28 heparin-based anticoagulation session, we observed a 100% success rate with a median session duration of 240 minutes in both RA and heparin groups. No early extracorporeal circulation (ECC) loss was reported. However, we noted significant differences in the post-dialysis ECC thrombosis scores, with higher Global Thrombosis Index (GTI) and higher membrane coagulation scores in the RA group (p < 0.007 and p < 0.02, respectively). No hypocalcaemia or hypercalcemia symptoms occurred. Median post-filter ionized calcium levels were 0.32 [0.29–0.39] mmol/L at 30 minutes and median patient ionized calcium levels was 1.19 [1.135–1.28] mmol/L at 60 minutes. No significant difference in per-dialysis arterial blood pressure was observed between groups. Conclusion Our study evaluated the RA approach using a calcium-free, citrate-free acetate dialysate in a chronic hemodialysis centre and found it effective. Although an acid-free dialysate was not used in this study, our findings suggest it could be the next frontier in the evolution of advanced dialysis techniques.