Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Germany.
Nephrol Dial Transplant. 2011 Jan;26(1):232-9. doi: 10.1093/ndt/gfq575. Epub 2010 Sep 27.
Continuous venovenous haemofiltration (CVVH) in the intensive care setting requires anticoagulation to prevent clotting of the extracorporeal circuit. Several protocols avoiding heparin and using regional citrate anticoagulation have been developed to diminish bleeding risks. However, data from randomized trials comparing citrate anticoagulation with systemic heparinization are very limited.
One hundred and seventy-four patients on mechanical ventilation, requiring renal replacement therapy for acute renal failure, were included in this prospective randomized multicentre trial comparing regional citrate with systemic heparin. The study was performed at nine different intensive care units at university or academic teaching hospitals. The participants were randomized to either CVVH using regional citrate anticoagulation or CVVH using systemic anticoagulation with unfractionated heparin. The primary outcome was to compare treatment efficacy represented by the patients' acid base status on Day 3 and on each consecutive day. Several parameters of safety and efficacy were analysed as secondary outcomes.
Comparison of standard bicarbonate from Day 3 to Day 11 revealed no difference between both treatment modalities. Use of citrate resulted in less systemic anticoagulation, a lower risk of bleeding and a longer haemofilter patency. Episodes of hypercalcaemia, hypocalcaemia and the need for additional bicarbonate infusions occurred more often under citrate. The patients' high mortality was not influenced by the mode of anticoagulation.
Citrate may be used as a regional anticoagulant and the only buffering agent in CVVH with adequate treatment efficacy and safety. However, neither citrate nor heparin anticoagulation should be regarded as a therapeutic standard, since there is no advantage of one of these substances with regard to patient mortality.
在重症监护环境中进行连续静脉-静脉血液滤过（CVVH）需要抗凝以防止体外回路凝血。已经开发了几种避免肝素并使用局部枸橼酸盐抗凝的方案，以降低出血风险。然而，比较枸橼酸盐抗凝与全身肝素化的随机试验数据非常有限。
本前瞻性随机多中心试验纳入了 174 名需要肾脏替代治疗急性肾衰竭而接受机械通气的患者，比较局部枸橼酸盐与全身肝素抗凝。该研究在 9 家不同的大学或学术教学医院的重症监护病房进行。参与者被随机分配到使用局部枸橼酸盐抗凝的 CVVH 或使用未分级肝素全身抗凝的 CVVH。主要结局是比较第 3 天和随后每天的患者酸碱状态的治疗效果。作为次要结局分析了几种安全性和疗效参数。
从第 3 天到第 11 天比较标准碳酸氢盐，两种治疗方式之间没有差异。使用枸橼酸盐导致全身抗凝减少，出血风险降低，血液滤过器通畅时间延长。枸橼酸盐组更常发生高钙血症、低钙血症和需要额外补充碳酸氢盐。患者的高死亡率不受抗凝方式的影响。
枸橼酸盐可用作 CVVH 的局部抗凝剂和唯一的缓冲剂，具有足够的治疗效果和安全性。然而，枸橼酸盐和肝素抗凝都不应被视为治疗标准，因为这两种物质在患者死亡率方面没有优势。
