A cost comparison of regional citrate versus low-dose systemic heparin anticoagulation in continuous renal replacement therapy

We compared the cost of continuous renal replacement therapy (CRRT) in critically ill patients using two different anticoagulation strategies: regional citrate and low-dose systemic heparin in a single-centre, prospective observational study in an adult Australian tertiary intensive care unit (ICU). All patients receiving CRRT between October 2015 and May 2016 were included in the study. Costs were modelled using the number of filter sets, number of dialysis bags, amount of citrate, heparin and calcium replacement required, and cost of monitoring the anticoagulation. The primary outcome was cost associated with CRRT per patient per day. The secondary outcome was efficacy of CRRT. In total, 66 patients were commenced on dialysis that required anticoagulation. Twenty-four patients were commenced on regional citrate anticoagulation and 42 patients commenced on systemic low-dose heparin anticoagulation. Median filter life, though not statistically significant, was longer in the citrate group by 7.7 hours (P=0.152), however the median cost of anticoagulation was AUD$317.91 higher in the citrate than the heparin group per patient per day (P=0.0020). While regional citrate anticoagulation may prolong filter life, it is also more expensive than low-dose systemic heparin. Choice of anticoagulation in CRRT should include cost as one of the variables that clinicians consider.