Current opinion in critical care
-
Accurate monitoring of the mechanical properties of the respiratory system is crucial to understand the pathophysiological mechanisms of respiratory failure in mechanically ventilated patients, to optimize mechanical ventilation settings and to reduce ventilator-induced lung injury. However, although the assessment of respiratory mechanics is simple in patients undergoing fully controlled ventilation, it becomes quite challenging in the presence of spontaneous breathing activity. Aim of the present review is to describe how the different components of respiratory mechanics [resistance, static compliance, and intrinsic positive end-expiratory pressure (PEEP)] can be measured at the bedside during assisted modes of ventilation. ⋯ Assessment of respiratory mechanics in spontaneously breathing patients, with some limitations, is feasible and should be included in everyday clinical practice; however, more data are needed to understand the clinical relevance of the measures obtained during assisted ventilation.
-
Curr Opin Crit Care · Feb 2020
ReviewTechniques to monitor respiratory drive and inspiratory effort.
There is increased awareness that derangements of respiratory drive and inspiratory effort are frequent and can result in lung and diaphragm injury together with dyspnea and sleep disturbances. This review aims to describe available techniques to monitor drive and effort. ⋯ Available techniques provide reliable measures of the intensity and timing of drive and effort. Simple, noninvasive techniques might be implemented in most patients and the more invasive or time-consuming in more complex patients at higher risk. We encourage clinicians to become familiar with technical details and physiological rationale of each for optimal implementation.
-
Curr Opin Crit Care · Feb 2020
ReviewSearching for the optimal positive end-expiratory pressure for lung protective ventilation.
The optimal strategy for setting positive end-expiratory pressure (PEEP) has not been established. This review examines different approaches for setting PEEP to achieve lung-protective ventilation. ⋯ When compared, no method for setting PEEP has been proven superior to another. Based on recent studies, higher compared with lower PEEP has not improved clinical outcomes and worsened mortality in one study. Future research should focus on identifying feasible methods for assessing lung recruitability in response to PEEP to enrich future trials of PEEP strategies.
-
Complications of mechanical ventilation, such as ventilator-induced lung injury (VILI) and ventilator-induced diaphragmatic dysfunction (VIDD), adversely affect the outcome of critically ill patients. Although mostly studied during control ventilation, it is increasingly appreciated that VILI and VIDD also occur during assisted ventilation. Hence, current research focuses on identifying ways to monitor and deliver protective ventilation in assisted modes. This review describes the operating principles of proportional modes of assist, their implications for lung and diaphragm protective ventilation, and the supporting clinical data. ⋯ Physiological rationale and clinical data suggest a potential role for proportional modes of assist in providing and monitoring lung and diaphragm protective ventilation.
-
Curr Opin Crit Care · Feb 2020
ReviewPatient self-inflicted lung injury and positive end-expiratory pressure for safe spontaneous breathing.
The potential risks of spontaneous effort and their prevention during mechanical ventilation is an important concept for clinicians and patients. The effort-dependent lung injury has been termed 'patient self-inflicted lung injury (P-SILI)' in 2017. As one of the potential strategies to render spontaneous effort less injurious in severe acute respiratory distress syndrome (ARDS), the role of positive end-expiratory pressure (PEEP) is now discussed. ⋯ To prevent P-SILI in ARDS, it seems feasible to facilitate 'safe' spontaneous breathing in patients using a higher PEEP strategy in severe ARDS.