简化计算机械功率的准确性:一个模拟研究
Haichong Zheng1, Zhiheng Xu1, Jing Zhou1
1Department of Critical Care Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Journal of thoracic disease
|July 10, 2023
概括
在机械通风 (MV) 过程中计算机械功率 (MP) 的代数公式可能是实际的,但可能会引入显著的偏差,特别是在ARDS患者中. 临床医生应该仔细选择配方,并专注于MP趋势,而不是绝对值.
科学领域:
- 关键护理医学 关键护理医学
- 呼吸系统生理学 呼吸系统生理学
- 生物医学工程 生物医学工程
背景情况:
- 机械通风 (MV) 是重症监护室 (ICU) 中一个关键的救命干预.
- 降低机械功率 (MP) 是优化 MV 的关键策略.
- 传统的MP计算方法是复杂的,促使人们对更简单的代数公式感兴趣.
研究的目的:
- 为了比较计算机械功率 (MP) 的不同代数公式的准确性和适用性.
- 在模拟急性呼吸困扰综合征 (ARDS) 条件下评估各种MP计算公式的性能.
主要方法:
- 一个肺模拟器 (TestChest) 用于通过改变肺部顺应来模拟各种ARDS肺部疾病.
- 风扇设置 (体积和压力控制模式) 和参数 (RR,Tinsp,PEEP) 进行了调整.
- 对控制体积的三种代数公式和控制压力通风的三种代数公式进行了评估,并与参考几何方法对比.
主要成果:
- 使用代数公式进行的MP计算显示与参考方法有显著的相关性 (R2 > 0.80).
- 在体积控制通风下,一个公式显著低估了MP.
- 在压力控制通风下,两个公式显著高估了MP,差异超过70%.
结论:
- 代数公式可以在MP计算中引入大量偏差,特别是在中度至严重的ARDS中.
- 仔细选择代数式MP公式至关重要,考虑到通风模式和患者状态.
- 在临床实践中,监测MP的趋势比依赖绝对计算值更有价值.
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