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使用临床输入变量的机械不均气泡中的应力和应变:一个简单的概念模型
John J Marini1, Patricia R M Rocco2, Lauren T Thornton3
1Department of Pulmonary and Critical Care Medicine, University of Minnesota, Minneapolis, St Paul, MN, USA. marin002@umn.edu.
Critical care (London, England)
|April 28, 2024
概括
通过考虑肺部单元张力和应力聚焦,可以改善肺部保护性通风. 新的模型帮助临床医生更好地通过计算机械不均性来估计呼吸器诱导的肺损伤 (VILI) 风险.
科学领域:
- 机械通风机械通风机械通风机
- 肺部生理学 肺部生理学
- 关键护理医学 关键护理医学
背景情况:
- 目前的肺部防护通风策略依赖于气道压力和体积,假设肺部应力和张力均.
- 机械上不均的肺,如在ARDS中,经历不均的应力分布,挑战这些假设.
- 风机引起的肺损伤 (VILI) 风险评估需要纳入除了标准风机电路测量之外的因素.
研究的目的:
- 扩展一个统一的肺部单元模型,以在不同合规的边界上表征应力和应变放大.
- 将可测量的通风功率与应力/应变放大集成在一起,以便对VILI风险有更精细的视角.
- 确定临床医生可识别和可测量的变量,可以改善VILI危险评估.
主要方法:
- 一个球形肺部单元的概念建模,其各个细分的合规性各不相同.
- 在合规接口边界的应力 (张力) 和应变 (区域变化) 放大的分析.
- 整合这些放大与可测量的通风功率.
主要成果:
- 静态条件揭示了不同合规性的肺段之间的边界处应力和应变的放大.
- 这些放大,当与通风功率一起考虑时,为VILI风险提供了新的视角.
- 确定了影响VILI危险的低估但可测量的变量.
结论:
- 标准的呼吸机监测可能会低估非均肺部的VILI风险.
- 考虑肺部单元的紧张,压力聚焦和功率度可以改善VILI风险评估.
- 对可测量的,非传统的参数进行进一步的研究是有必要的,以优化肺部防护通风.
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