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Kidney Week

Abstract: FR-PO462

Flexitrate Regional Citrate Anticoagulation in Continuous Venovenous Hemodiafiltration

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Lenga, Ilan, Lakeridge Health, Oshawa, Ontario, Canada
  • Hopman, Wilma M., Queen's University, Kingston, Alberta, Canada
  • O'Connell, Adam J., Lakeridge Health, Oshawa, Ontario, Canada
  • Hume, Francesca, Lakeridge Health, Oshawa, Ontario, Canada
  • Wei, Charles C., Lakeridge Health, Oshawa, Ontario, Canada

This study compared Flexitrate, an innovative regional citrate anticoagulation (RCA) protocol, to traditional RCA (tRCA) and Heparin anticoagulation protocols in intensive care patients treated with continuous renal replacement therapy (CRRT).


A single-center, retrospective, cohort study, was conducted in a 26-bed ICU in a large community hospital. Consecutive patients from a 6 month pilot of Flexitrate CRRT were compared to consecutive patients from the preceding 9 months receiving tRCA and Heparin CRRT anticoagulation. 80 dialysis sessions (Flexitrate = 2,852 hours, tRCA = 3,580 hours and Heparin = 2,026 hours), performed in 53 patients, were evaluated for filter life, RCA control, and metabolic control.


Filter survival was significantly improved with Flexitrate compared to tRCA (HR 0.24, p=0.018) and Heparin (HR 0.14, p=0.004); see attached Figure.
Anticoagulation control was superior with Flexitrate with Patient Ionized Calcium out of target a median of 16% of the time, compared to 27% for tRCA (p<0.001). Filter Ionized Calcium was out of target a median of 6.8% of the time, compared to 23% for tRCA (p= 0.03).
Flexitrate produced significantly less alkalosis, hypernatremia, and hypocalcemia than tRCA, and was comparable to Heparin anticoagulation. The only adverse metabolic outcome with Flexitrate was more Hypomagnesemia.


The Flexitrate protocol extended filter life, delivered more consistent anticoagulation, and provided superior metabolic control compared to a tRCA protocol. Filter life was also superior to Heparin anticoagulation, with similar metabolic control. A randomized control trial comparing these protocols is recommended.

Dialysis Filter Survival for the three protocols, censored for filter clotting.