This study assessed the safety and efficacy of a commercial low-
citrate concentration-based pre-filter replacement fluid during continuous veno-venous haemofiltration (CVVH) in patients with frequent filter clotting and high risk of
bleeding. We used a commercial low-
citrate fluid as pre-dilution replacement fluid during CVVH (
citrate: 11 mmol/l (33 meq/l),
sodium: 140 mmol/l,
chloride: 108 mmol/l and
potassium: 1 mmol/l). A
calcium and
magnesium infusion was delivered separately by central line for the maintenance of serum ionized
calcium (Cai) and total
magnesium (Mg). In this prospective observational study, 30 patients, 124 filters and 1,515 treatment-hours were observed. Median filter life of
citrate CVVH was 9.5 hours. Filter life in the 48 hours prior to
citrate CVVH was also observed. In the patients on prior non-
anticoagulant CVVH (n=14) filter life increased significantly with
citrate (9.5 hours vs 5 hours; P<0.0001). In patients on prior
heparin CVVH (n = 15), filter life was similar with
citrate (10 hours vs 8 hours; P = 0.68). However, in patients with prior early/frequent filter clotting despite
heparin (n = 11) filter life increased significantly (10 hours vs 7 hours; P=0.038). Of 411 serum Cai measurements, none showed a Cai < 0.85 mmol/l and, of 84 observations, none showed a serum Mg<0. 6 mmol/l. One patient with
sepsis and
shock needed to cease
citrate CVVH because of progressive ionized hypocalcaemia and increasing anion gap. No other adverse effects were observed. In selected patients, CVVH with a commercial low-
citrate concentration
solution as pre-filter replacement fluid and a simultaneous
calcium and
magnesium infusion protocol appears generally safe. Filter life was acceptable and superior to that achieved with previous treatment.