弗雷泽方程的外部验证,用于估计严重病情严重的成年人自由氨酸度
Andrew J Webb1, Caitlin S Brown2, JiTong Liu3
1Department of Pharmacy, Massachusetts General Hospital, Boston, Massachusetts, USA.
Pharmacotherapy
|November 17, 2025
概括
弗雷泽方程适度估计了重症患者的自由氨酸度,但低估了更高的水平. 对于精确的氨酸监测,仍然建议直接测量.
科学领域:
- 在重症监护中的药理动力学和药理动力学.
- 临床化学和治疗药物的监测.
背景情况:
- 危急病患者可能因蛋白质结合的改变而过度暴露瓦尔酸.
- 弗雷泽方程是为了估计该人群中的自由酸度而开发的,但需要外部验证.
研究的目的:
- 为了对Fraser方程进行外部验证,以估计成人重症监护室 (ICU) 患者的自由烯酸盐度.
- 将弗雷泽方程与多雷方程的性能进行比较,并评估治疗一致性.
主要方法:
- 包括具有同时自由和总氨酸测量的成年ICU患者.
- 为了估计,使用了Fraser方程,包括总的酸,白蛋白,BUN,醇和阿司匹林使用量.
- 布兰德-阿尔特曼方法评估了方程性能,以及治疗一致性分析.
主要成果:
- 弗雷泽方程显示中等相关性 (r=0.728),但负偏差,低估了较高的测量度.
- 弗雷泽方程估计达到了71%的治疗一致性,超过多雷方程 (61.9%,p=0.001).
- 修改稍微提高了性能,但没有解决低估在较高度.
结论:
- 弗雷泽方程为自由酸盐的估计提供了适度的准确性,但不足以取代直接测量.
- 在较高度下低估的情况凸显了在重症患者中直接测量自由氨酸的必要性.
- 当直接测量延迟或不可用时,弗雷泽方程可以补充治疗决策.
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