Background: Regional citrate anticoagulation (RCA) is being used increasingly in critically ill patients who require continuous renal replacement therapy (CRRT). RCA may be avoided in patients with liver disease because of perceived increased risk of metabolic complications. The study compares the circuit lifespan and metabolic complications using RCA for CRRT at varying levels of liver dysfunction.
Methods: Data was collected retrospectively including the number of days on CRRT, number of circuit (re)initiations within that time and serum ionized and total calcium, bicarbonate, and sodium, repeatedly during treatment. Model for end-stage liver disease (MELD) scores were calculated and patients were divided into 4 groups according to MELD score quartiles.
Results: A total of 697 patients were included in the present study. The median circuit survival time was not different between groups. The median minimum serum ionized calcium levels during treatment were significantly lower in groups 3 and 4 (p<0.001), but by the last day of treatment, mean serum ionized calcium levels were not different between groups. The median minimum bicarbonate levels were significantly lower in groups 3 and 4 compared with groups 1 and 2 (p<0.01), but this is not considered clinically significant. The median maximum and mean serum bicarbonate levels were not significant between groups. Total to ionized calcium ratio levels were similar in groups 1, 2 and 3, but significantly higher in group 4 compared with other groups.
Conclusion: RCA is a reasonably safe form of anticoagulation for maintaining efficiency and patency of the dialyzer in critically ill patients with liver dysfunction.