Seminars in respiratory and critical care medicine
-
Semin Respir Crit Care Med · Feb 2019
ReviewRole of Pharmacologic Paralysis in Acute Respiratory Distress Syndrome.
The pharmacology and history of neuromuscular blockade in clinical care are complex, with multiple theoretical and observed potential benefits and potential harms. Past studies raised concern for long-term paresis, but more recent studies have not found evidence for harm, possibly due to changes in background care, neuromuscular blocking agent, and duration of blockade. Current use is highly variable, likely due to limited evidence for efficacy beyond short-term physiologic improvement and lingering concerns for harm. A recently completed large multicenter trial will provide further information on the role of pharmacologic paralysis in acute respiratory distress syndrome.
-
Acute respiratory distress syndrome (ARDS) is a syndrome of acute respiratory failure caused by noncardiogenic pulmonary edema. Despite five decades of basic and clinical research, there is still no effective pharmacotherapy for this condition and the treatment remains primarily supportive. It is critical to study the molecular and physiologic mechanisms that cause ARDS to improve our understanding of this syndrome and reduce mortality. ⋯ First, we will describe how pulmonary edema fluid accumulates in ARDS due to lung inflammation and increased alveolar endothelial and epithelial permeabilities. Next, we will review how pulmonary edema fluid is normally cleared in the uninjured lung, and describe how these pathways are disrupted in ARDS. Finally, we will explain how clinical trials and preclinical studies of novel therapeutic agents have further refined our understanding of this condition, highlighting, in particular, the study of mesenchymal stromal cells in the treatment of ARDS.
-
Semin Respir Crit Care Med · Feb 2019
ReviewAcute Respiratory Distress Syndrome: Respiratory Monitoring and Pulmonary Physiology.
The high prevalence of acute respiratory distress syndrome (ARDS), its morbidity and mortality continue to fare a huge burden in the intensive care unit. More than 40 years ago, experimental studies have highlighted that, albeit essential, mechanical ventilation could be harmful to lungs and more recently to the diaphragm. Despite life-saving advances in mechanical ventilation (such as low tidal-volume ventilation, neuromuscular blockers agents, or prone positioning), a recent international observational study reported that most ARDS patients were not appropriately monitored. ⋯ To achieve this goal, it is of paramount importance to better understand the complex relationship between the patient and the ventilator: the impact of ventilator settings on lungs during passive controlled ventilation, but also of patient's breathing efforts on lungs during assisted ventilation. In this review we present available tools to monitor respiratory mechanics at the bedside aiming at optimizing and personalizing mechanical ventilation. Hopefully, this careful management can decrease mortality of patients with ARDS in the future.
-
Semin Respir Crit Care Med · Feb 2019
ReviewDefinitions, Epidemiology, Clinical Risk Factors, and Health Disparities in Acute Respiratory Distress Syndrome.
Acute respiratory distress syndrome (ARDS) is a syndrome of inflammatory lung injury currently defined as the rapid onset of hypoxemia and radiographic opacities from a recent direct or indirect insult that is not explained by other causes. While the diagnostic criteria used to define ARDS are helpful in the clinical setting, they are not entirely specific for the characteristic pathophysiology of diffuse alveolar lung damage. ⋯ Within these limitations, ARDS appears to be a condition that is relatively rare within the general population but common within the context of the intensive care unit. Furthermore, the frequency and outcomes of ARDS seem to vary between populations, with no clearly discernible temporal trends in incidence or case fatality that are uniform across studies.