Regional Citrate Anticoagulation

It is unclear whether different modes of continuous renal replacement therapy (CRRT) impact post-filter ionized calcium concentrations during regional citrate anticoagulation (RCA) when using calcium-containing replacement fluid. This prospective, single-center, observational cohort study will screen all patients receiving CRRT for eligibility. General clinical information will be collected before commencing CRRT treatment. Patients will be randomly assigned to either the veno-venous hemofiltration (CVVH) or continuous veno-venous hemodialysis (CVVHD) group and switch to the alternative mode in the subsequent treatment session. Pre-filter and post-filter ionized calcium, systemic total and ionized calcium, and effluent total and ionized calcium will be measured 2 hours after the initiation of CRRT. Electrolyte levels, arterial blood gases, hourly citrate dose, and total citrate dose will be recorded every 6 hours until the end of CRRT. The primary outcome is the difference in ionized calcium concentrations at each site over time between the two modes.