Citrate doubles CRRT filter lifespan: A real-world Chinese cohort study

Abstract

Background:

Continuous renal replacement therapy (CRRT) plays a crucial role in the management of acute kidney injury (AKI) and fluid overload among critically ill patients. Despite its clinical significance, comprehensive real-world evidence from the Chinese population regarding the clinical application of CRRT, including anticoagulation strategies and factors influencing therapeutic efficacy, remains scarce.

Methods:

This retrospective cohort study was performed to examine all CRRT treatments administered in the ICU of a tertiary Grade A hospital from July 1 to August 31, 2025. A total of 238 CRRT sessions fulfilling the inclusion criteria were analyzed. Data collected encompassed patient demographics, illness severity scores (APACHE II and SOFA), CRRT treatment parameters, anticoagulation strategies, laboratory indicators, and causes leading to treatment discontinuation. The primary outcome comprised filter survival time, which was analyzed using Kaplan–Meier analysis and Cox proportional hazards models.

Results:

The analysis included 238 sessions derived from 187 patients (median age 67; 61.3% male). CVVH was the most commonly applied modality (55.9%). Meanwhile, citrate anticoagulation was employed in 49.6% of sessions, followed by heparin (28.2%). The predominant reason for discontinuation was filter clotting (33.6%). Multivariable analysis revealed that the use of citrate anticoagulation was associated with a significantly reduced risk of filter clotting compared to heparin (HR = 0.49, 95% CI 0.29–0.81, p = 0.006). Likewise, a blood flow rate exceeding 150 mL/min was associated with a protective effect (HR = 0.65, 95% CI 0.43–0.98, p = 0.039), whereas mechanical ventilation was associated with an increased risk of filter clotting (HR = 2.15, 95% CI 1.16–3.99, p = 0.015). Finally, median filter survival was 38.5 h for citrate, 18.0 h for heparin, and 26.0 h for nafamostat (log-rank p < 0.001).

Conclusion:

This real-world study demonstrates a strong association between citrate anticoagulation and extended filter lifespan during CRRT, supporting its role as the preferred anticoagulation approach in this setting. Moreover, maintaining adequate blood flow rates and adopting customized anticoagulation management for mechanically ventilated patients may further enhance CRRT efficacy. These findings collectively provide valuable real-world evidence to inform clinical decision-making.