CKRT in Patients With Acute Kidney Injury, Liver Failure

There are conflicting opinions on the efficacy and safety of no anticoagulation versus regional citrate anticoagulation for treatment of acute kidney injury (AKI) with continuous renal replacement therapy (CKRT) in patients with severe liver failure at high risk for bleeding. Ming Bai and colleagues reported results of a randomized, controlled trial assessing both therapies for CKRT in that patient population. 

The study cohort included patients who were randomized to receive regional citrate anticoagulation or no-anticoagulation CKRT. The primary end point of interest was filter failure. 

Forty-two patients were randomized to the regional citrate anticoagulation CKRT group and 45 were randomized to the no-anticoagulation CKRT group. The filter failure rate in the no-anticoagulation group was significantly higher than in the regional citrate anticoagulation group (25 [56%] vs 12 [27%], respectively; P=.003). 

The finding was confirmed by cumulative incidence function analysis and sensitivity analysis including only the first CKRT sessions. In the cumulative incidence function analysis, the cumulative filter failure rates at 24, 48, and 72 hours of the no-anticoagulation group were 31%, 58%, and 76%, respectively, compared with 11%, 23%, and 35% in the regional citrate anticoagulation group. 

The incidences of CA²+_tot/Ca²+_ion >2.5, hypocalcemia, and severe hypocalcemia were significantly higher in the regional citrate group than in the no-anticoagulation group (7% vs 57%; P<.001, 51% vs 82%; P=.002, and 13% vs 77%; P<.0010). Most (73%) of the increased CA²+_tot/Ca²+_ion ratios were normalized following the upregulation of the calcium substitution rate. There was no significant additional increase in the systemic citrate concentration after 6 hours in the regional citrate anticoagulation group. 

In conclusion, the researchers said, “For patients with liver failure with a higher bleeding risk who required CKRT, regional citrate anticoagulation resulted in significantly longer filter lifespan than no anticoagulation. However, regional citrate anticoagulation in patients with liver failure was associated with a significantly higher risk of hypocalcemia, severe hypocalcemia, and CA²+_tot/Ca²+_ion >2.5.” 

Source: Clinical Journal of the American Society of Nephrology