Anticoagulant effect of low concentration plasma trisodium citrate in continuous veno-venous hemofiltration

Effective anticoagulation is a prerequisite of continuous renal replacement therapy (CRRT). During CRRT, prolonged anticoagulant therapy should be administered to prevent extracorporeal clotting. The purpose of our study was to evaluate whether a low concentration of plasma trisodium citrate (TCA) was effective as an anticoagulation treatment for continuous veno-venous hemofiltration (CVVH). We also retrospectively analyzed the complications of regional citrate anticoagulation (RCA) in our hospital.

We conducted this single-center retrospective study at a tertiary academic hospital. The study period was from July 1, 2019 to January 1, 2021. CVVH using the RCA protocol during the study period was performed. The RCA protocol and complications were included and analyzed. The concentrations of citrate in the blood and plasma were calculated.

In the current study, we used low-dose TCA as an anticoagulant in 288 CVVH runs for 78 patients. The median whole blood and plasma citrate concentrations were 2.13 mmol/L and 2.84 mmol/L, respectively. Although only a low concentration of citrate was used, RCA achieved expected anticoagulation and ensured the life span of the hemofilter during CVVH therapy. Although hypocalcemia was common during RCA, serious consequences could be prevented by timely adjustment of the protocol. Citrate intoxication was rare in patients without relative contraindications for citric acid. We did not find RCA-associated hypernatremia.

We recommend the use of a low concentration of TCA (2.5-3.0 mmol/L in plasma) in extracorporeal solution in the RCA protocol. Although RCA may cause some complications, serious complications can be prevented. Mild hypocalcemia and transient metabolic alkalosis can be corrected in a timely manner. We do not believe hypernatremia is a complication of RCA if the RCA protocol is appropriately applied.