Wang Fang, Lin Li, Li Peiyun, Huang Xianli, Ye Ting, Sun Xiankun, Tang Xue, Zhang Min, Zhang Sheng, Yang Yingying, Zhao Yuliang, Zhang Ling, Chen Zhiwen
Department of Nephrology, West China Hospital, Sichuan University/West China School of Nursing, Sichuan University, Chengdu, China.
Department of Nephrology, Kidney Research Institute, West China Hospital, Sichuan University, Chengdu, China.
BMC Nurs. 2025 Aug 25;24(1):1109. doi: 10.1186/s12912-025-03762-x.
Regional citrate anticoagulation (RCA) is the preferred strategy during continuous renal replacement therapy (CRRT). However, saline flushing is often used when anticoagulants are contraindicated, although its effectiveness remains uncertain. This study evaluated the efficacy of different saline flushing strategies in preventing circuit clotting during anticoagulant-free CRRT in critically ill patients.
This prospective, three-arm randomized controlled trial included critically ill patients initiating CRRT who had contraindications to anticoagulants. Patients were randomized into three groups: 30-minute flush (200 mL every 30 minutes), 2-hour flush (200 mL every 2 hours), or no flush. The primary outcome was circuit lifespan. The secondary outcomes included the delivered CRRT dose, filtration fraction, nurse satisfaction, length of hospital stay, 28-day mortality, and hypotension incidence within 2 hours of CRRT initiation.
Among 144 randomized patients, 117 (81%) completed the trial: 38 in the 30-minute flush group, 37 in the 2-hour flush group, and 42 in the no-flush group. The mean circuit lifespan was shorter in the 30-minute group (31.03 ± 20.26 h) than in the 2-hour (41.96 ± 18.26 h) and no-flush groups (42.10 ± 19.29 h)(p < 0.05). Significant differences were observed among the 30-minute flush, 2-hour flush, and no-flush groups in terms of delivered CRRT dose (89%, 95% vs. 98%, p < 0.001), filtration fraction (16.14%, 14.05% vs. 13.07%, p < 0.001), and nurse satisfaction (32.26, 62.04 vs. 93.93, p < 0.001). The 30-minute flush group had a higher hypotension incidence within 2 hours of CRRT initiation compared to the no-flush group (71.05% vs. 42.85%, p < 0.017, Bonferroni-adjusted). No significant differences were found in the number of clotting-free patients at 72 hours, hospital stay, or 28-day mortality (p > 0.05).
Frequent saline flushing does not appear to effectively prevent circuit clotting and may be associated with increased hypotension, reduced delivered CRRT dose, higher filtration fraction, and lower nurse satisfaction. These findings suggest that saline flushing should be used cautiously in anticoagulant-free CRRT.
Chinese Clinical Trial Registry:ChiCTR2400080111(01/20/2024).
局部枸橼酸抗凝（RCA）是持续肾脏替代治疗（CRRT）期间的首选策略。然而，当抗凝剂禁忌时，常使用生理盐水冲洗，但其有效性仍不确定。本研究评估了不同生理盐水冲洗策略在危重症患者无抗凝CRRT期间预防体外循环凝血的疗效。
这项前瞻性、三臂随机对照试验纳入了开始进行CRRT且有抗凝剂禁忌证的危重症患者。患者被随机分为三组：30分钟冲洗组（每30分钟200毫升）、2小时冲洗组（每2小时200毫升）或不冲洗组。主要结局是体外循环寿命。次要结局包括实际给予的CRRT剂量、滤过分数、护士满意度、住院时间、28天死亡率以及CRRT开始后2小时内的低血压发生率。
在144例随机分组的患者中，117例（81%）完成了试验：30分钟冲洗组38例，2小时冲洗组37例，不冲洗组42例。30分钟冲洗组的平均体外循环寿命（31.03±20.26小时）短于2小时冲洗组（41.96±18.26小时）和不冲洗组（42.10±19.29小时）（p<0.05）。在实际给予的CRRT剂量（89%、95%对98%，p<0.001）、滤过分数（16.14%、14.05%对13.07%，p<0.001）和护士满意度（32.26、62.04对93.93，p<0.001）方面，30分钟冲洗组、2小时冲洗组和不冲洗组之间存在显著差异。与不冲洗组相比，30分钟冲洗组在CRRT开始后2小时内的低血压发生率更高（71.05%对42.85%，p<0.017，经Bonferroni校正）。在72小时无凝血患者数量、住院时间或28天死亡率方面未发现显著差异（p>0.05）。
频繁的生理盐水冲洗似乎不能有效预防体外循环凝血，且可能与低血压增加、实际给予的CRRT剂量减少、滤过分数升高和护士满意度降低有关。这些发现表明，在无抗凝CRRT中应谨慎使用生理盐水冲洗。
中国临床试验注册中心：ChiCTR2400080111（2024年1月20日）。
