Regional citrate anticoagulation circuit for the PrismaFlex machine with pre and post dilution CVVHDF using calcium-containing solutions. Prismasate and Prismasol are the commercial dialysate and substitutions fluid solutions sourced from Baxter (Baxter, Dearborn Chicago). Abbreviations: QB, blood flow rate; QR1, pre-filter fluid flow rate; QD, dialysate flow rate; QR2, post-filter fluid flow rate; QE, effluent flow rate; QFR, patient fluid removal rate. * Commercial solutions