口服抗凝血剂的临界值
K E Brummel1, S G Paradis, R F Branda
1Department of Biochemistry, Given Building, Health Science Complex University of Vermont, College of Medicine, Burlington, USA.
Circulation
|November 7, 2001
概括
华法林治疗显示出血凝时间和血凝-抗血凝III (TAT) 概况的显著变化,即使具有类似的国际规范化比率 (INR). 这表明抗凝血控制可能不如预期那么安全,个体反应会影响出血和凝血风险.
科学领域:
- 血液学 血液学 血液学
- 药理学 药理学是指药理学的学科.
- 临床医学 临床医学
背景情况:
- 监测口服抗凝药对于预防出血和血栓形成至关重要.
- 华法林治疗需要谨慎管理,以保持治疗疗效.
- 个体患者对抗凝血剂的反应可能会有很大差异.
研究的目的:
- 在华法林治疗的患者中研究全血凝固,其类似的国际规范化比率 (INR).
- 评估凝血概况和血栓-抗血栓III (TAT) 生成的变异性.
- 探索INR,凝血参数和XIII因子水平之间的关系.
主要方法:
- 在8名接受华法林治疗的男性受试者 (W组) 和一名多次受试者 (A组) 中研究了组织因子诱导的全血凝结.
- 测量了凝血时间,血-抗血III (TAT) 形成率和水平,血小板激活和纤维蛋白A代.
- 评估了VIII因子水平,并将其与多年华法林治疗相关联.
主要成果:
- 具有相似INR的受试者在凝血时间 (6.2-23分钟) 和TAT概况方面表现出很大的差异.
- 正常对照组的凝血时间较短 (5.7±0.3分钟),TAT水平较高 (742±91nmol/L).
- 与对照组 (149.4±37.4%) 相比,W组的VIII因子水平显著增加 (204±34.4%),与华法林治疗持续时间相关 (r=0.78,P=0.01).
结论:
- 将抗凝血控制到设定的INR治疗范围可能不如预期那么安全.
- 在具有相似INRs的患者中,组织因子凝血反应存在显著的个体变异.
- 这种变异性表明出血和血栓形成的风险不同,可能与潜在的血管异常和补偿机制有关,如增加的第八因子.
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