两种成人振荡器通气特性的比较：一项肺模型研究。

Comparison of the ventilation characteristics in two adult oscillators: a lung model study.

作者信息

Yumoto Tetsuya, Fujita Takahisa, Asaba Sunao, Kanazawa Shunsuke, Nishimatsu Atsunori, Yamanouchi Hideo, Nakagawa Satoshi, Nagano Osamu

机构信息

Advanced Emergency and Critical Care Medical Center, Okayama University Hospital, 2-5-1, Shikata-cho, Kita-ku, Okayama, 700-8558, Japan.

Center for Innovative and Translational Medicine, Kochi University Medical School, 185-1, Kohasu, Oko-cho, Nankoku, Kochi, 783-8505, Japan.

出版信息

Intensive Care Med Exp. 2019 Mar 12;7(1):15. doi: 10.1186/s40635-019-0229-2.

DOI:10.1186/s40635-019-0229-2

PMID:30868327

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6419651/

Abstract

BACKGROUND

Two recent large randomized controlled trials did not show the superiority of high-frequency oscillatory ventilation (HFOV) in adults with ARDS. These two trials had differing results, and possible causes could be the different oscillators used and their different settings, including inspiratory time % (IT%). The aims of this study were to obtain basic data about the ventilation characteristics in two adult oscillators and to elucidate the effect of the oscillator and IT% on ventilation efficiency.

METHODS

The Metran R100 or SensorMedics 3100B was connected to an original lung model internally equipped with a simulated bronchial tree. The actual stroke volume (aSV) was measured with a flow sensor placed at the Y-piece. Carbon dioxide (CO) was continuously insufflated into the lung model ([Formula: see text]CO), and the partial pressure of CO (PCO) in the lung model was monitored. Alveolar ventilation ([Formula: see text]A; L/min) was estimated as [Formula: see text]CO divided by the stabilized value of PCO. [Formula: see text]A was evaluated with several stroke volume settings in the R100 (IT = 50%) or several airway pressure amplitude settings in the 3100B (IT = 33%, 50%) at a frequency of 6 and 8 Hz, a mean airway pressure of 25 cmHO, and a bias flow of 30 L/min. Assuming that [Formula: see text]A = frequency × aSV, values of a and b were determined. Ventilation efficiency was calculated as [Formula: see text]A divided by actual minute ventilation.

RESULTS

The relationship between aSV and [Formula: see text]A or ventilation efficiency were different depending on the oscillator and IT%. The values of a and b were 0 < a < 1 and 1 < b < 2 and were different for three conditions at both frequencies. [Formula: see text]A and ventilation efficiency were highest with R100 (IT = 50%) and lowest with 3100B (IT = 33%) for high aSV ranges at both frequencies.

CONCLUSIONS

In this lung model study, ventilation characteristics were different depending on the oscillator and IT%. Ventilation efficiency was highest with R100 (IT = 50%) and lowest with 3100B (IT = 33%) for high aSV ranges.

摘要

背景

最近两项大型随机对照试验未显示高频振荡通气（HFOV）在成人急性呼吸窘迫综合征（ARDS）患者中的优越性。这两项试验结果不同，可能原因是所使用的振荡器及其设置不同，包括吸气时间百分比（IT%）。本研究的目的是获取两种成人振荡器通气特性的基础数据，并阐明振荡器和IT%对通气效率的影响。

方法

将美敦力R100或SensorMedics 3100B连接到内部配备模拟支气管树的原始肺模型上。通过放置在Y形管处的流量传感器测量实际潮气量（aSV）。向肺模型中持续吹入二氧化碳（[公式：见正文]CO），并监测肺模型中二氧化碳的分压（PCO）。肺泡通气量（[公式：见正文]A；L/分钟）通过[公式：见正文]CO除以PCO的稳定值来估算。在频率为6和8Hz、平均气道压为25cmH₂O、偏流为30L/分钟的条件下，在R100中用几种潮气量设置（IT = 50%）或在3100B中用几种气道压振幅设置（IT = 33%、50%）对[公式：见正文]A进行评估。假设[公式：见正文]A = 频率×aSV，确定a和b的值。通气效率通过[公式：见正文]A除以实际分钟通气量来计算。