Emergency medicine updates: Acute respiratory distress Syndrome.

INTRODUCTION

Acute respiratory distress syndrome (ARDS) is a critical condition associated with severe morbidity and mortality. There are several components of management, and it is important for emergency clinicians to be aware of these as they manage critically ill patients who may face extended time in the emergency department.

OBJECTIVE

This paper evaluates evidence-based updates concerning ARDS.

DISCUSSION: ARDS is a condition associated with diffuse, severe lung inflammation resulting in hypoxemic respiratory failure. While there have been several definitions, the most recent conceptual model is based on the revised Berlin definition and incorporates risk factors, the underlying etiology, timing, chest imaging, and oxygenation. Management is primarily based on ventilation and oxygenation, with literature demonstrating that low tidal volumes (4-8 mL/kg of predicted body weight) with plateau pressure  ≤30 cm H2O are associated with improved outcomes, and settings should be optimized to target driving pressure < 15 cm H2O. Resuscitation with intravenous fluids should be individualized, though overall a net neutral-to-negative fluid balance may be beneficial. Steroids should be considered in those with moderate-to-severe ARDS within 14 days of onset, but administration past 14 days after ARDS onset may worsen outcomes. Neuromuscular blocking agents may be used in those with severe ARDS and refractory hypoxemia or ventilator dyssynchrony. Prone positioning should be considered in patients with moderate-to-severe ARDS who fail to improve despite lung-protective ventilation or in those with high ventilator settings and should ideally be performed for at least 12-16 consecutive hours per day. Patients with severe ARDS refractory to low tidal volume ventilation and other adjunctive therapies may be managed with veno-venous extracorporeal membrane oxygenation (ECMO) at an ECMO center.

CONCLUSIONS

An understanding of literature updates can improve the ED care of patients with ARDS.