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Purpose of review: This article discusses recently published articles reporting the incidence and outcome of patients with the acute respiratory distress syndrome (ARDS). This is a difficult task since there is a marked variability regarding the methodology of the few, large epidemiological, and observational studies on ARDS. Recent findings: The review will mainly focus on publications from the past 18 months. We have reviewed new epidemiological studies reporting population-based incidence of ARDS. Also, we have reviewed the data on survival reported in observational and randomized controlled trials, discussed how the current ARDS definition modifies the true incidence of ARDS, and briefly mentioned recent approaches that appear to improve ARDS outcome. Summary: On the basis of current evidence, it seems that the incidence and overall hospital mortality of ARDS has not changed substantially in the last decade. Independent of the definition used for identification of ARDS patients, reported population-based incidence of ARDS is an order of magnitude lower in Europe than in the USA. Current hospital mortality of combined moderate and severe ARDS reported in observational studies is greater than 40%.

Purpose of review: The optimal strategy for assessing and preventing ventilator-induced lung injury in the acute respiratory distress syndrome (ARDS) is controversial. Recent investigative efforts have focused on personalizing ventilator settings to individual respiratory mechanics. This review examines the strengths and weaknesses of using transpulmonary pressure measurements to guide ventilator management in ARDS. Recent findings: Recent clinical studies suggest that adjusting ventilator settings based on transpulmonary pressure measurements is feasible, may improve oxygenation, and reduce ventilator-induced lung injury. Summary: The measurement of transpulmonary pressure relies upon esophageal manometry, which requires the acceptance of several assumptions and potential errors. Notably, this includes the ability of localized esophageal pressures to represent global pleural pressure. Recent investigations demonstrated improved oxygenation in ARDS patients when positive end-expiratory pressure was adjusted to target specific end-inspiratory or end-expiratory transpulmonary pressures. However, there are different methods for estimating transpulmonary pressure and different goals for positive end-expiratory pressure titration among recent studies. More research is needed to refine techniques for the estimation and utilization of transpulmonary pressure to guide ventilator settings in ARDS patients.

Purpose of review: Acute respiratory distress syndrome (ARDS) is a devastating disease process with a 40% mortality rate, and for which there is no therapy. Stem cells are an exciting potential therapy for ARDS, and are currently the subject of intensive ongoing research efforts. We review data concerning the therapeutic promise of cell-based therapies for ARDS. Recent findings: Recent experimental studies suggest that cell-based therapies, particularly mesenchymal stem/stromal cells (MSCs), endothelial progenitor cells, and embryonic or induced pluripotent stem cells all offer considerable promise for ARDS. Of these cell types, mesenchymal stromal cells offer the greatest potential for allogeneic therapy, given the large body of preclinical data supporting their use, and the advanced state of our understanding of their diverse mechanisms of action. Although other stem cells such as EPCs also have therapeutic potential, greater barriers exist, particularly the requirement for autologous EPC therapy. Other stem cells, such as ESCs and iPSCs, are at an earlier stage in the translational process, but offer the hope of directly replacing injured lung tissue. Ultimately, lung-derived stem cells may offer the greatest hope for lung diseases, given their homeostatic role in replacing and repairing damaged native lung tissues. MSCs are currently in early phase clinical trials, the results of which will be of critical importance to subsequent translational efforts for MSCs in ARDS. A number of translational challenges exist, including minimizing variability in cell batches, developing standard tests for cell potency, and producing large amounts of clinical-grade cells for use in patients. Summary: Cell-based therapies, particularly MSCs, offer considerable promise for the treatment of ARDS. Overcoming translational challenges will be important to fully realizing their therapeutic potential for ARDS.

Purpose of review: Although results from clinical trials have advanced the treatment of acute respiratory distress syndrome (ARDS), mortality remains high. More recently, focus has shifted from treatment of ARDS to early identification and prevention in at-risk populations. Recent findings: There have been 30 published and registered clinical trials with either the primary or secondary goal of reducing ARDS. Summary: With this change in paradigm, come additional challenges and consideration in study design that depends not only on the intervention but also whether the intervention aims for a primary, secondary, or tertiary prevention of ARDS that targets a patient population for universal, selective, or indicated prevention. These epidemiologic concepts of prevention in public health also apply to ARDS and are relevant to the study population to target, the timing of the intervention relative to critical illness, the study design and outcomes to measure in an ARDS prevention study. This shift in focus is reflected by the new National Heart Lung Blood Institute Prevention and Early Treatment of Acute Lung Injury network, and signifies an overall movement away from reacting to and supporting acute organ failure after it is established to early detection and prevention in acute critical illness wherever and whenever it may occur.

Purpose of review: Circulatory failure is a frequent complication during acute respiratory distress syndrome (ARDS) and is associated with a poor outcome. This review aims at clarifying the mechanisms of circulatory failure during ARDS. Recent findings: For the past decades, the right ventricle (RV) has gained a crucial interest since many authors confirmed the high incidence of acute cor pulmonale during ARDS and showed a potential role of the acute cor pulmonale in the poor outcome of ARDS patients. The most important recent progress demonstrated in ARDS ventilatory strategy is represented by the prone position, which has a huge beneficial effect on RV afterload. This review will focus on the mechanisms responsible for the RV dysfunction/failure during ARDS and on the strategy, which allows improving the right ventricular function. Summary: The RV has a pivotal role in the circulatory failure of ARDS patients. The ventilatory strategy during ARDS has to pay a peculiar attention to the RV to rigorously control its afterload.

Purpose of review: The objective of this article is to review the most recent literature regarding the management of acute hypercapnic respiratory failure (AHRF). Recent findings: In the field of AHRF management, noninvasive ventilation (NIV) has become the standard method of providing primary mechanical ventilator support. Recently, extracorporeal carbon dioxide removal (ECCO2R) devices have been proposed as new therapeutic option. Summary: NIV is an effective strategy in specific settings and in selected population with AHRF. To date, evidence on ECCO2R is based only on case reports and case-control trials. Although the preliminary results using ECCO2R to decrease the rate of NIV failure and to wean hypercapnic patients from invasive ventilation are remarkable; further randomized studies are needed to assess the effects of this technique on both short-term and long-term clinical outcomes.

Purpose of review: The purpose of the review is to alert clinicians to the prevalent and frequently underrecognized problem of asynchrony in mechanically ventilated patients. To provide a mechanistic model of patient-ventilator asynchrony to help personnel understand how different asynchronies develop. To provide practical advice on how to recognize and solve different asynchronies in different contexts. Recent findings: Patient-ventilator asynchrony is a serious problem that is associated with prolonged mechanical ventilation, prolonged ICU and hospital stays, and increased mortality. Asynchronies can occur in all modes of invasive and noninvasive ventilation in all care contexts. Summary: The review provides insights into the causes of patient-ventilator asynchrony and mechanisms involved in the development of specific types of asynchrony. It explores the effects of sedation on the development of asynchrony and the impact of new ventilator modes. It also discusses the prevalence of asynchrony and its effects on outcome.

Purpose of review: The aim of this review is to analyze innovative data pertaining to the clinical use of mechanical ventilation for children. Recent findings: The optimal definition and treatment of pediatric acute respiratory distress syndrome, the application of innovative ventilation modes in children to optimize child/ventilator interaction, and pediatric noninvasive ventilation, including specific interfaces, have been recently evaluated in the literature. Summary: Despite the improvement observed in the last decades in the treatment of pediatric acute respiratory failure and the diffusion of innovative modes of mechanical ventilation, there are no clear and consistent guidelines for the use of mechanical ventilation for children. In several areas data are still lacking, and in many others they are extrapolated from studies performed in adults; the direct evaluation of results obtained from studies specific to the pediatric population is therefore crucial.

Purpose of review: The purpose of the review is to summarize and discuss recent research regarding the role of mechanical ventilation in producing weakness and atrophy of the diaphragm in critically ill patients, an entity termed ventilator-induced diaphragmatic dysfunction (VIDD). Recent findings: Severe weakness of the diaphragm is frequent in mechanically ventilated patients, in whom it contributes to poor outcomes including increased mortality. Significant progress has been made in identifying the molecular mechanisms responsible for VIDD in animal models, and there is accumulating evidence for occurrence of the same cellular processes in the diaphragms of human patients undergoing prolonged mechanical ventilation. Summary: Recent research is pointing the way to novel pharmacologic therapies as well as nonpharmacologic methods for preventing VIDD. The next major challenge in the field will be to move these findings from the bench to the bedside in critically ill patients.

Purpose of review: Despite advances in extracorporeal membrane oxygenation (ECMO) technology, much is unknown about the optimal management strategies for patients receiving extracorporeal support. There is a growing body of literature investigating patient selection and outcomes, mechanical ventilation approaches, anticoagulation, pharmacokinetics, early mobilization, and the role of ECMO transport among others. Recent findings: Nonrandomized data suggest a survival advantage from ECMO compared with conventional management in acute respiratory distress syndrome, with mechanical ventilation practices varying widely across centers. A randomized controlled trial is currently ongoing with standardized ventilation approaches in both arms. Low-level anticoagulation appears to be well tolerated, and ECMO circuitry appears to affect the pharmacokinetics of certain drugs. Pilot and matched cohort studies suggest that extracorporeal carbon dioxide removal is effective in preventing intubation in chronic obstructive pulmonary disease, with larger randomized studies being planned. ECMO may be successful in bridging selected patients to lung transplantation, with early mobilization serving as a well tolerated and effective means of optimizing these patients. Regionalization of ECMO may maximize outcomes and is facilitated by the development of ECMO transport teams. Summary: Recently published data highlight the evolving management strategies of patients receiving extracorporeal support and help identify those patients most appropriate for ECMO and extracorporeal carbon dioxide removal. More data will ultimately be needed to develop an evidence-based consensus.

Purpose of review: The purpose is to review the development and current application of extracorporeal life support [ECLS, extracorporeal membrane oxygenation (ECMO)] in acute severe respiratory failure. Recent findings: Extracorporeal support (ECMO) is used for acute severe respiratory failure in advanced ICUs. The current survival rate is 60–70%. Three controlled trials all demonstrated 20–30% improvement in survival compared to conventional care. Patients may now be maintained awake and ambulatory with spontaneous breathing. Summary: ECMO is the next step in the algorithm for management of severe respiratory failure unresponsive to conventional care.