Anticoagulants are frequently used to prevent thrombosis of the dialysis filter in patients on continuous kidney replacement therapy (CKRT). However, there is ambiguity about the clinical decision about the anticoagulation strategy to be used. Despite the current guidelines suggesting the use of regional citrate anticoagulation as first-line treatment for continuous kidney replacement therapy in critically ill patients, there are limited clinical trials and meta-analyses to provide clinical evidence for the recommendation.

The results of a randomized controlled trial showed that patients treated with regional citrate anticoagulants had a longer filter life span (47 versus 26 hours) but also a higher frequency of new infections (68 versus 55 percent). The study included600 critically ill patients with acute kidney injury receiving CKRT, where patients treated with regional citrate anticoagulant were compared with those treated with systemic heparin infusion. The results also showed that the rates of 90-day mortality were similar between the groups. This clinical trial supported the recommendation of preferring regional citrate anticoagulation over systemic heparin for anticoagulation with CKRT.

The regional citrate anticoagulation involves the addition of a citrate solution to the blood before the filter of the extracorporeal dialysis circuit. It consists of citrate infusion to the blood before the filter of the extracorporeal circuit, by chelating ionized calcium, a key cofactor of many steps of the clotting cascade; the calcium-citrate complexes are then primarily removed by filtration and dialysis. It has been associated with longer filter life span, a quality indicator of the procedure.

The results of the clinical trial concluded that among critically ill patients with acute kidney injury receiving continuous kidney replacement therapy, anticoagulation with regional citrate, compared with the systemic heparin anticoagulation, led to significantly longer filter life span.

Reference

1  Zarbock A., et al. Effect of regional citrate anticoagulation vs systemic heparin anticoagulation during continuous kidney replacement therapy on dialysisfilter life span and mortality among critically ill patients with acute kidney injury: A randomized clinical trial. JAMA. 2020; 324(16):1629.