Evenepoel Pieter, Dejagere Tom, Verhamme Peter, Claes Kathleen, Kuypers Dirk, Bammens Bert, Vanrenterghem Yves
Department of Medicine, Division of Nephrology, University Hospital Leuven, Leuven, Belgium.
Am J Kidney Dis. 2007 May;49(5):642-9. doi: 10.1053/j.ajkd.2007.02.001.
Hemodialysis requires anticoagulation to prevent clotting of the extracorporeal circuit. Systemic anticoagulation with heparin is contraindicated in patients at high risk of bleeding. In these patients, regional citrate anticoagulation (RCA), with either calcium-free (RCA-Ca0) or calcium-containing dialysate (RCA-Ca3.0), and heparin-coated membranes (1.3 m(2); AN69ST; Nephral 300ST, Gambro-Hospal, Meyzieu, France) may represent valid alternatives.
To compare the efficacy and safety of these regional anticoagulation modalities, we performed a prospective randomized trial including 33 hemodialysis patients at high risk of bleeding. Regional anticoagulation was achieved by means of either AN69ST (11 patients, 31 sessions), RCA-Ca0 (11 patients, 32 sessions), or RCA-Ca3.0 (11 patients, 30 sessions). Patients assigned to RCA were dialyzed using a polysulfone membrane (1.3 m(2); F60; Fresenius Medical Care, Bad Homburg, Germany). Scheduled dialysis time was 4 hours. At the end of each dialysis session, the dialyzer was inspected for visible signs of thrombus formation and scored semiquantitatively (0, no clotting, to 4, severe clotting). Solute clearances were monitored at the second and fourth treatment hour as a parameter of subclinical clotting of the dialyzer.
Clotting phenomena necessitating premature termination of the dialysis session were encountered in 39%, 13%, and 0% using AN69ST, RCA-Ca3.0, and RCA-Ca0, respectively (P < 0.005). All clotting with AN69ST occurred after the second treatment hour. Mean dialyzer clotting scores were 2.7, 1.5, and 1.1, respectively (P < 0.0001). Significantly greater instantaneous urea nitrogen clearances were achieved at 2 hours during RCA compared with AN69ST. Except for clotting phenomena, no adverse events were observed.
Citrate provides superior regional anticoagulation compared with AN69ST membranes.
血液透析需要进行抗凝以防止体外循环凝血。对于出血风险高的患者，全身性肝素抗凝是禁忌的。在这些患者中，使用无钙（RCA-Ca0）或含钙透析液（RCA-Ca3.0）的局部枸橼酸盐抗凝（RCA）以及肝素涂层膜（1.3平方米；AN69ST；Nephral 300ST，法国甘布罗-霍斯帕尔公司，梅齐厄）可能是有效的替代方法。
为比较这些局部抗凝方式的疗效和安全性，我们进行了一项前瞻性随机试验，纳入了33例出血风险高的血液透析患者。通过使用AN69ST（11例患者，31次透析）、RCA-Ca0（11例患者，32次透析）或RCA-Ca3.0（11例患者，30次透析）实现局部抗凝。分配到RCA组的患者使用聚砜膜（1.3平方米；F60；德国费森尤斯医疗公司，巴特洪堡）进行透析。预定透析时间为4小时。在每次透析结束时，检查透析器有无血栓形成的可见迹象并进行半定量评分（0分表示无凝血，4分表示严重凝血）。在治疗的第2小时和第4小时监测溶质清除率，作为透析器亚临床凝血的一个参数。
使用AN69ST、RCA-Ca3.0和RCA-Ca0时，分别有39%（P<0.005）、13%和0%的患者出现需要提前终止透析的凝血现象。使用AN69ST时所有凝血均发生在治疗第2小时之后。平均透析器凝血评分分别为2.7、1.5和1.1（P<0.0001）。与AN69ST相比，RCA组在2小时时的即时尿素氮清除率显著更高。除凝血现象外，未观察到不良事件。
与AN69ST膜相比，枸橼酸盐提供了更好的局部抗凝效果。
