概括
对静脉血栓栓塞的肝素剂量显示,抗凝剂反应在个体之间有显著的差异. 这些因素包括肝素清除的差异及其对激活部分血栓形成时间 (APTT) 的影响.
科学领域:
- 药理学 药理学是指药理学的学科.
- 血液学 血液学 血液学
- 临床医学 临床医学
背景情况:
- 静脉血栓塞栓症 (VTE) 需要有效的抗凝治疗.
- 氨酸是一种常用的抗凝剂,但它的有效性可能有所不同.
- 了解个体对肝素的反应对于优化治疗至关重要.
研究的目的:
- 调查VTE患者对标准肝素治疗方案的药理动力学和药理动力学反应.
- 确定导致氨酸抗凝效应在个体之间变化的因素.
- 评估肺栓塞对肝素半衰期的影响.
主要方法:
- 研究了20名接受标准肝素剂量的VTE患者 (70单位/千克IV玻尿酸,然后400单位/千克/24小时输液).
- 随着时间的推移,测量了血肝素活性和激活的部分血栓形成时间 (APTT).
- 使用血肝素活性和APTT计算肝素清除率和半衰期.
主要成果:
- 对抗凝血剂效果和对肝素的反应观察到显著的个体间差异.
- 归因于氨酸清除率和APTT对氨酸反应的差异的变化 (氨酸效应指数).
- 肝素半衰期为63±15分钟 (血活性) 和84±71.5分钟 (APTT);在肺栓塞患者中显著缩短 (P<0.005).
结论:
- 标准的肝素剂量在静脉瘤患者中表现出相当大的个体间差异.
- 氨酸清除率及其对APTT的影响是抗凝剂反应的关键决定因素.
- 肺栓塞与肝素半衰期缩短有关,这表明肝素代谢或清除发生了变化.
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