Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Clin J Am Soc Nephrol. 2011 May;6(5):1018-24. doi: 10.2215/CJN.07240810. Epub 2011 Apr 14.
To determine whether warfarin prolongs the time to first mechanical-catheter failure.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This was a multicenter parallel-group randomized controlled trial with blinding of participants, trial staff, clinical staff, outcome assessors, and data analysts. Randomization was in a 1:1 ratio in blocks of four and was concealed by use of fax to a central pharmacy. Hemodialysis patients with newly-placed catheters received low-intensity monitored-dose warfarin, target international normalized ratio (INR) 1.5 to 1.9, or placebo, adjusted according to schedule of sham INR results. The primary outcome was time to first mechanical-catheter failure (inability to establish a circuit or blood flow less than 200 ml/min).
We randomized 174 patients: 87 to warfarin and 87 to placebo. Warfarin was associated with a hazard ratio (HR) of 0.90 (P=0.60; 95% confidence interval [CI], 0.57, 1.38) for time to first mechanical-catheter failure. Secondary analyses were: time to first guidewire exchange or catheter removal for mechanical failure (HR 0.78; 95% CI, 0.37, 1.6); time to catheter removal for mechanical failure (HR 0.67; 95% CI, 0.19, 2.37); and time to catheter removal for any cause (HR 0.89; 95% CI, 0.42, 1.81). Major bleeding occurred in 10 participants assigned to warfarin and seven on placebo (relative risk, 1.43; 95% CI, 0.57, 3.58; P=0.61).
We found no evidence for efficacy of low-intensity, monitored-dose warfarin in preventing mechanical-catheter failure.
确定华法林是否会延长首次机械导管故障的时间。
设计、地点、参与者和测量：这是一项多中心平行组随机对照试验，参与者、试验人员、临床人员、结果评估人员和数据分析师均设为盲法。采用四组随机分组，组间以 1:1 比例进行随机化，分组通过传真隐藏至中央药房。新置入导管的血液透析患者接受低强度监测剂量华法林治疗，目标国际标准化比值（INR）为 1.5 至 1.9，或安慰剂治疗，根据模拟 INR 结果的时间表进行调整。主要结局是首次发生机械导管故障（无法建立回路或血流小于 200ml/min）的时间。
我们共随机分配了 174 名患者：87 名接受华法林治疗，87 名接受安慰剂治疗。华法林治疗与首次发生机械导管故障的时间的风险比（HR）为 0.90（P=0.60；95%置信区间[CI]，0.57，1.38）。次要分析结果为：首次因机械故障而需要交换导丝或导管取出的时间（HR 0.78；95% CI，0.37，1.6）；因机械故障而需要导管取出的时间（HR 0.67；95% CI，0.19，2.37）；以及因任何原因而需要导管取出的时间（HR 0.89；95% CI，0.42，1.81）。10 名接受华法林治疗的患者和 7 名接受安慰剂治疗的患者发生了主要出血（相对风险，1.43；95% CI，0.57，3.58；P=0.61）。
我们没有发现低强度、监测剂量华法林在预防机械导管故障方面有任何疗效证据。
