在ARDS中估计机械功率的压力控制替代公式与死亡率有关
Richard H Kallet1, Michael S Lipnick1
1Mr. Kallet and Dr. Lipnick are affiliated with Department of Anesthesia and Perioperative Care, University of California, San Francisco at San Francisco General Hospital, San Francisco, California.
Respiratory care
|September 6, 2024
概括
呼吸系统机械功率 (MP_RS) 的简化公式准确预测ARDS患者的死亡风险. 较高的MP_RS水平始终会使死亡风险增加两倍以上,有助于临床评估.
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
- 机械通风机械通风机械通风
背景情况:
- 对呼吸系统 (MP_RS) 施加的机械功率 (MP) 是 ARDS 患者的呼吸器诱导肺损伤 (VILI) 和死亡率的已知风险因素.
- 由于缺乏自动化呼吸机集成,精确的MP_RS测量具有挑战性,需要使用复杂的方程或简化的替代品.
- 简化MP_RS替代公式的准确性与已建立的气道压力-体积曲线方法相美.
研究的目的:
- 评估简化压力控制替代方程的准确性,以评估ARDS患者的死亡风险.
- 为了确定这种代用方程在主要使用体积控制 (VC) 通风管理的患者中是否有效.
- 为了在不同ARDS严重程度分类中比较幸存者和非幸存者之间的MP_RS水平.
主要方法:
- 对948名ARDS患者进行了回顾性观察性研究,在ARDS发作后24小时内接受侵入性机械通风,生存时间超过24小时.
- MP_RS 用公式计算:0.098 x 呼吸频率 x 潮体积 x (PEEP + 驱动压力).
- MP_RS被评估为医院死亡的风险因素,与未幸存者和幸存者进行比较,并分析了四个已确定的值 (15,20,25,30 J/min).
主要成果:
- MP_RS与死亡风险增加显著相关 (OR 1.06 [1.04-1.07],P < .001).
- 与轻度,中度和重度ARDS分类的幸存者相比,非幸存者的MP_RS水平中位数显著更高 (P < .001到P = .034).
- 当MP_RS超过确定的值时,死亡率大幅增加 (23-29%对38-51%),在MP_RS较高的组中,死亡率的几率比率>2.0.
结论:
- 简化压力控制替代公式MP_RS对于评估ARDS患者的死亡风险是准确的,包括那些接受VC通风的人.
- 超过VILI或死亡风险的确定的MP_RS截止值,患者的死亡率会持续增加两倍以上.
- 这种简化公式为临床医生提供了一种实用工具,以识别高风险ARDS患者,并可能指导通风策略.
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