Effect of nafamostat mesylate anticoagulation and regional citrate anticoagulation during continuous renal replacement therapy in critically ill patients: a retrospective study of efficacy and safety

Regional citrate anticoagulation (RCA) is recommended for critically ill patients at high bleeding risk undergoing continuous renal replacement therapy (CRRT). Nafamostat mesylate (NM), a short-half-life serine protease inhibitor, is a popular alternative in East Asia. Direct comparisons of their efficacy and safety are limited. This retrospective single-center study included 81 critically ill patients receiving CRRT with either NM (<i>n</i> = 31) or RCA (<i>n</i> = 50) from January 2022 to January 2023. The primary outcome was filter lifespan. Secondary outcomes included circuit patency, bleeding events, and metabolic complications. The median filter lifespan was significantly shorter in the NM group compared to the RCA group (23.4 <i>vs.</i> 29.6 h, <i>p</i> = 0.02). The NM group also had a higher rate of unplanned circuit discontinuation (52.3 <i>vs.</i> 39.1%, <i>p</i> = 0.03). Multivariable analysis confirmed RCA was independently associated with a lower risk of circuit failure (HR = 0.44, <i>p</i> = 0.03). Although not statistically significant, trends favored NM regarding metabolic safety, with lower incidences of severe metabolic alkalosis (16.1 <i>vs.</i> 36.0%, <i>p</i> = 0.09) and hypocalcemia (9.7 <i>vs.</i> 26.0%, <i>p</i> = 0.13). RCA demonstrated superior anticoagulation efficacy in prolonging filter survival, while NM may offer a more favorable metabolic safety profile. The choice of anticoagulant should be individualized based on efficacy priorities and metabolic risk.