Acute respiratory distress syndrome

This article reviews the evolving definitions and epidemiology of the acute respiratory distress syndrome (ARDS) and highlights current efforts to improve identification of high-risk patients, thus to target prevention and early treatment before progression to ARDS. This information will be important for general practitioners and intensivists interested in improving the care of patients at risk for ARDS, and clinical researchers interested in designing clinical trials targeting the prevention and early treatment of acute lung injury...

Acute respiratory distress syndrome (ARDS) remains a major cause of morbidity and mortality in critically ill patients. Over the past several decades, alcohol abuse and cigarette smoke exposure have been identified as risk factors for the development of ARDS. The mechanisms underlying these relationships are complex and remain under investigation but are thought to involve pulmonary immune impairment and alveolar epithelial and endothelial dysfunction. This review summarizes the epidemiologic data supporting links between these exposures and ARDS susceptibility and outcomes and highlights key mechanistic investigations that provide insight into the pathways by which each exposure is linked to ARDS...

The acute respiratory distress syndrome (ARDS) is a heterogeneous group of illnesses affecting the pulmonary parenchyma with acute onset bilateral inflammatory pulmonary infiltrates with associated hypoxemia. ARDS occurs after 2 major types of pulmonary injury: direct lung injury affecting the lung epithelium or indirect lung injury disrupting the vascular endothelium. Greater understanding of the differences between direct and indirect lung injury may refine the classification of patients with ARDS and lead to development of new therapeutics targeted at specific subpopulations of patients with ARDS...

Given the high incidence and mortality of acute respiratory distress syndrome (ARDS) in critically ill patients, every practitioner needs a bedside approach both for early identification of patients at risk for ARDS and for the appropriate evaluation of patients who meet the diagnostic criteria of ARDS. Recent advances such as the Lung Injury Prediction score, the Early Acute Lung Injury score, and validation of the SpO(2)/Fio(2) ratio for assessing the degree of hypoxemia are all practical tools to aid the practitioner in caring for patients at risk of ARDS...

The cornerstone of lung protective ventilation in patients with acute respiratory distress syndrome (ARDS) is a pressure- and volume-limited strategy. Other interventions have also been investigated. Although no method for positive end-expiratory pressure (PEEP) titration has proven most advantageous, experimental and clinical data support the use of higher PEEP in patients with moderate/severe ARDS. There is no benefit to the early use of high-frequency oscillatory ventilation (HFOV) in patients with moderate/severe ARDS, although it may be considered as rescue therapy...

Multiple animal and human studies have shown that prone positioning improves oxygenation and reduces ventilator-induced lung injury (VILI) in the setting of acute lung injury or acute respiratory distress syndrome (ARDS). In this article, the physiologic changes explaining the improvement in oxygenation are reviewed, how prone positioning reduces VILI is described, randomized controlled trials of prone ventilation in patients with ARDS are evaluated, the complications associated with prone ventilation are summarized, suggestions are made as to how these might be reduced or avoided, and when prone ventilation should start and stop and for what duration it should be used are discussed...

Interest in the role of neuromuscular blocking agents (NMBAs) in the treatment of acute respiratory distress syndrome (ARDS) has been renewed since a recent randomized clinical trial showed a reduction in mortality associated with the use of NMBAs. However, the role of paralytics in a protective mechanical ventilation strategy should be detailed. This review summarizes data in the literature concerning the clinical effects of NMBAs on the outcome of patients with ARDS, in an attempt to explain some pathophysiologic hypotheses concerning their action and to integrate them into the overall management strategy for the mechanical ventilation of ARDS patients...

The early history of extracorporeal membrane oxygenation (ECMO) for adult patients with the acute respiratory distress syndrome (ARDS) evolved slowly over decades, a consequence of extracorporeal technology with high risk and unclear benefit. However, advances in component technology, accumulating evidence, and growing experience in recent years have resulted in a resurgence of interest in ECMO. Extracorporeal support, though currently lacking high-level evidence, has the potential to improve outcomes, including survival, in ARDS...

The development and severity of acute respiratory distress syndrome (ARDS) are closely related to dysregulated inflammation, and the duration of ARDS and eventual outcomes are related to persistent inflammation and abnormal fibroproliferation. Corticosteroids are potent modulators of inflammation and inhibitors of fibrosis that have been used since the first description of ARDS in attempts to improve outcomes. There is no evidence that corticosteroids prevent the development of ARDS among patients at risk. High-dose and short-course treatment with steroids does not improve the outcomes of patients with ARDS...

Acute respiratory distress syndrome (ARDS) remains challenging to diagnose and manage. This article reviews the new definition of ARDS and the key findings of landmark studies over the last 5 years of prone-position ventilation, high-frequency oscillatory ventilation (HFOV), extracorporeal membrane oxygenation (ECMO), and neuromuscular blockade in patients with ARDS.