Rabec C, Rodenstein D, Leger P, Rouault S, Perrin C, Gonzalez-Bermejo J
Service de pneumologie et réanimation respiratoire, CHU de Dijon, 2, boulevard du Maréchal-de-Lattre-de-Tassigny, 21079 Dijon, France.
Rev Mal Respir. 2013 Dec;30(10):818-31. doi: 10.1016/j.rmr.2013.08.001. Epub 2013 Oct 30.
Compared with invasive ventilation, non-invasive ventilation (NIV) has two unique characteristics: its non-hermetic nature and the fact that the ventilator-lung assembly cannot be considered as a single-compartment model because of the presence of variable resistance represented by the upper airways. When NIV is initiated, the ventilator settings are determined empirically based on clinical evaluation and blood gas variations. However, NIV is predominantly applied during sleep. Consequently, to assess overnight patient-machine "agreement" and efficacy of ventilation, more specific and sophisticated monitoring is needed. The effectiveness of NIV might therefore be more correctly assessed by sleep studies than by daytime assessment. The simplest monitoring can be done from flow and pressure curves from the mask or the ventilator circuit. Examination of these tracings can give useful information to evaluate if the settings chosen by the operator were the right ones for that patient. However, as NIV allows a large range of ventilatory parameters and settings, it is mandatory to have information about this to better understand patient-ventilator interaction. Ventilatory modality, mode of triggering, pressurization slope, use or not of positive end expiratory pressure and type of exhalation as well as ventilator performances may all have physiological consequences. Leaks and upper airway resistance variations may, in turn, modify these patterns. This article discusses the equipment available for NIV, analyses the effect of different ventilator modes and settings and of exhalation and connecting circuits on ventilatory traces and gives the background necessary to understand their impact on nocturnal monitoring of NIV.
与有创通气相比，无创通气（NIV）有两个独特的特点：其非密闭性，以及由于上气道所代表的可变阻力的存在，呼吸机-肺组件不能被视为单室模型。启动无创通气时，呼吸机设置是根据临床评估和血气变化凭经验确定的。然而，无创通气主要在睡眠期间应用。因此，为了评估夜间患者与机器的“匹配度”和通气效果，需要更具体、更复杂的监测。因此，通过睡眠研究评估无创通气的有效性可能比白天评估更准确。最简单的监测可以通过面罩或呼吸机回路的流量和压力曲线来进行。检查这些描记图可以提供有用的信息，以评估操作者选择的设置是否适合该患者。然而，由于无创通气允许大范围的通气参数和设置，必须了解这些信息才能更好地理解患者与呼吸机的相互作用。通气方式、触发模式、增压斜率、是否使用呼气末正压和呼气类型以及呼吸机性能都可能产生生理影响。漏气和上气道阻力变化反过来可能会改变这些模式。本文讨论了可用于无创通气的设备，分析了不同呼吸机模式和设置以及呼气和连接回路对通气描记图的影响，并给出了理解它们对无创通气夜间监测影响所需的背景知识。
