Outcomes of Patients Presenting with Mild Acute Respiratory Distress Syndrome: Insights from the LUNG SAFE Study.

Background: Patients with initial mild acute respiratory distress syndrome are often underrecognized and mistakenly considered to have low disease severity and favorable outcomes. They represent a relatively poorly characterized population that was only classified as having acute respiratory distress syndrome in the most recent definition. Our primary objective was to describe the natural course and the factors associated with worsening and mortality in this population.

Extracorporeal carbon dioxide removal for lowering the risk of mechanical ventilation: research questions and clinical potential for the future.

As a result of technical improvements, extracorporeal carbon dioxide removal (ECCOR) now has the potential to play an important role in the management of adults with acute respiratory failure. There is growing interest in the use of ECCOR for the management of both hypoxaemic and hypercapnic respiratory failure. However, evidence to support its use is scarce and several questions remain about the best way to implement this therapy, which can be associated with serious side-effects.

Diaphragmatic myotrauma: a mediator of prolonged ventilation and poor patient outcomes in acute respiratory failure.

Several mechanisms of diaphragm muscle injury (myotrauma) can result in ventilator-induced diaphragm dysfunction, including ventilator over-assistance, under-assistance, eccentric contractions, and end-expiratory shortening. In this Personal View, we summarise the evidence for the clinical relevance of these mechanisms, and present new data based on mediation analysis supporting the hypothesis that myotrauma due to ventilator over-assistance and under-assistance contribute, in part, to the effect of mechanical ventilation on clinical outcomes. The concept of diaphragmatic myotrauma has important implications for research and clinical practice.

Spontaneous Breathing in Early Acute Respiratory Distress Syndrome: Insights From the Large Observational Study to UNderstand the Global Impact of Severe Acute Respiratory FailurE Study.

Objectives: To describe the characteristics and outcomes of patients with acute respiratory distress syndrome with or without spontaneous breathing and to investigate whether the effects of spontaneous breathing on outcome depend on acute respiratory distress syndrome severity.

Design: Planned secondary analysis of a prospective, observational, multicentre cohort study.

Setting: International sample of 459 ICUs from 50 countries.

Obstructive sleep apnea in patients surviving acute hypercapnic respiratory failure is best predicted by static hyperinflation.

Rationale: Acute hypercapnic respiratory failure (AHRF) treated with non-invasive ventilation in the ICU is frequently caused by chronic obstructive pulmonary disease (COPD) exacerbations and obesity-hypoventilation syndrome, the latter being most often associated with obstructive sleep apnea. Overlap syndrome (a combination of COPD and obstructive sleep apnea) may represent a major burden in this population, and specific diagnostic pathways are needed to improve its detection early after ICU discharge.

Objectives: To evaluate whether pulmonary function tests can identify a high probability of obstructive sleep apnea in AHRF survivors and outperform common screening questionnaires to identify the disorder.

High-flow nasal oxygen versus noninvasive ventilation in adult patients with cystic fibrosis: a randomized crossover physiological study.

Background: Noninvasive ventilation (NIV) is the first-line treatment of adult patients with exacerbations of cystic fibrosis (CF). High-flow nasal oxygen therapy (HFNT) might benefit patients with hypoxemia and can reduce physiological dead space. We hypothesized that HFNT and NIV would similarly reduce work of breathing and improving breathing pattern in CF patients.

Flexibility of nanolayers and stacks: implications in the nanostructuration of clays.

The basic structural units of adsorbing microporous materials such as clays and cementitious materials are flexible nanolayers. The flexibility of these layers is reported to play a crucial role in the structuration of these materials, potentially affecting therefore the thermo-mechanical behavior of such materials. Adsorbed fluids are structured in a discrete number of layers within the space between the nanolayers in these materials.

Pressure support ventilation + sigh in acute hypoxemic respiratory failure patients: study protocol for a pilot randomized controlled trial, the PROTECTION trial.

Background: Adding cyclic short sustained inflations (sigh) to assisted ventilation yields optimizes lung recruitment, decreases heterogeneity and reduces inspiratory effort in patients with acute hypoxemic respiratory failure (AHRF). These findings suggest that adding sigh to pressure support ventilation (PSV) might decrease the risk of lung injury, shorten weaning and improve clinical outcomes. Thus, we conceived a pilot trial to test the feasibility of adding sigh to PSV (the PROTECTION study).

Asynchrony Consequences and Management.

Poor synchrony between the delivery of mechanical breaths, the neural respiratory timing, and needs of patients is relatively frequent under mechanical ventilation in the intensive care unit. This review summarizes the current knowledge on the different types of dyssynchrony described to date, their mechanism, consequences, and potential management. There is still a long way to get to a comprehensive knowledge and uncertainties remain.

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome.

Background: The efficacy of venovenous extracorporeal membrane oxygenation (ECMO) in patients with severe acute respiratory distress syndrome (ARDS) remains controversial.

Methods: In an international clinical trial, we randomly assigned patients with very severe ARDS, as indicated by one of three criteria - a ratio of partial pressure of arterial oxygen (Pao) to the fraction of inspired oxygen (Fio) of less than 50 mm Hg for more than 3 hours; a Pao:Fio of less than 80 mm Hg for more than 6 hours; or an arterial blood pH of less than 7.25 with a partial pressure of arterial carbon dioxide of at least 60 mm Hg for more than 6 hours - to receive immediate venovenous ECMO (ECMO group) or continued conventional treatment (control group).

How Ventilation Is Delivered During Cardiopulmonary Resuscitation: An International Survey.

Background: Recommendations regarding ventilation during cardiopulmonary resuscitation (CPR) are based on a low level of scientific evidence. We hypothesized that practices about ventilation during CPR might be heterogeneous and may differ worldwide. To address this question, we surveyed physicians from several countries on their practices during CPR.

Continuous Negative Abdominal Pressure Reduces Ventilator-induced Lung Injury in a Porcine Model.

Background: In supine patients with acute respiratory distress syndrome, the lung typically partitions into regions of dorsal atelectasis and ventral aeration ("baby lung"). Positive airway pressure is often used to recruit atelectasis, but often overinflates ventral (already aerated) regions. A novel approach to selective recruitment of dorsal atelectasis is by "continuous negative abdominal pressure.

Resolved versus confirmed ARDS after 24 h: insights from the LUNG SAFE study.

Purpose: To evaluate patients with resolved versus confirmed ARDS, identify subgroups with substantial mortality risk, and to determine the utility of day 2 ARDS reclassification.

Methods: Our primary objective, in this secondary LUNG SAFE analysis, was to compare outcome in patients with resolved versus confirmed ARDS after 24 h. Secondary objectives included identifying factors associated with ARDS persistence and mortality, and the utility of day 2 ARDS reclassification.

Esophageal pressure monitoring: why, when and how?

Purpose Of Review: Esophageal manometry has shown its usefulness to estimate transpulmonary pressure, that is lung stress, and the intensity of spontaneous effort in patients with acute respiratory distress syndrome. However, clinical uptake of esophageal manometry in ICU is still low. Thus, the purpose of review is to describe technical tips to adequately measure esophageal pressure at the bedside, and then update the most important clinical applications of esophageal manometry in ICU.

Continuous negative abdominal pressure: mechanism of action and comparison with prone position.

We recently reported that continuous negative abdominal pressure (CNAP) could recruit dorsal atelectasis in experimental lung injury and that oxygenation improved at different transpulmonary pressure values compared with increases in airway pressure (Yoshida T, Engelberts D, Otulakowski G, Katira BH, Post M, Ferguson ND, Brochard L, Amato MBP, Kavanagh BP. Am J Respir Crit Care Med 197: 534-537, 2018). The mechanism of recruitment with CNAP is uncertain, and its impact compared with a commonly proposed alternative approach to recruitment, prone positioning, is not known.

Inspiratory Muscle Rehabilitation in Critically Ill Adults. A Systematic Review and Meta-Analysis.

Rationale: Respiratory muscle weakness is common in critically ill patients; the role of targeted inspiratory muscle training (IMT) in intensive care unit rehabilitation strategies remains poorly defined.

Objectives: The primary objective of the present study was to describe the range and tolerability of published methods for IMT. The secondary objectives were to determine whether IMT improves respiratory muscle strength and clinical outcomes in critically ill patients.

International Practice Variation in Weaning Critically Ill Adults from Invasive Mechanical Ventilation.

Rationale: Randomized trials and meta-analyses have informed several aspects of weaning. Results are rarely replicated in practice, as evidence is applied in intensive care units that differ from the settings in which it was generated.

Objectives: We aimed to: 1) describe weaning practice variation (identifying weaning candidates, conducting spontaneous breathing trials, using ventilator modes, and other aspects of care during weaning); 2) characterize regional differences in weaning practices; and 3) identify factors associated with practice variation.