Regional citrate anticoagulation in patients with liver failure supported by a molecular adsorbent recirculating system

Objective: Regional citrate anticoagulation has emerged as a promising method in critically ill patients at high risk of bleeding. However, in patients with liver failure, citrate accumulation may lead to acid-base and electrolyte imbalances, notably of calcium. The aim of this study was to evaluate the feasibility and safety of regional citrate anticoagulation during liver support using a molecular adsorbent recirculating system as well as its effects on electrolyte and acid-base balance in patients with liver failure. Design: Prospective observational study. Setting: University hospital. Patients: Twenty critically ill patients supported by molecular adsorbent recirculating system resulting from liver failure between January 2007 and May 2009. Measurements and Main Results: The median duration of molecular adsorbent recirculating system treatment was 20 hrs (interquartile range, 18-22 hrs). Two of 77 molecular adsorbent recirculating system treatments (2%) were prematurely discontinued as a result of filter clotting and bleeding, respectively. The median citrate infusion rate, necessary to maintain the postfilter ionized calcium between 0.2 and 0.4 mmol/L, was 3.1 mmol/L (interquartile range, 2.3-4 mmol/L) blood flow. The median calcium chloride substitution rate was 0.9 mmol/L (0.3-1.7 mmol/L) dialysate. Total serum calcium remained stable during molecular adsorbent recirculating system treatments. There was a statistically significant increase of the ratio of total calcium to systemic ionized calcium (2.04 +/- 0.32 mmol/L to 2.17 +/- 0.35; p = .01), which reflected citrate accumulation resulting from liver failure. Under close monitoring, no clinically relevant electrolytes or acid-base disorders were observed. Conclusions: Our results suggest that regional citrate anticoagulation is a safe and feasible method to maintain adequate circuit lifespan without increasing the risk of hemorrhagic complications while maintaining a normal acid-base as well as electrolyte balance in patients with liver failure supported by molecular adsorbent recirculating system. (Crit Care Med 2011; 39: 273-279)