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Introduction
Sepsis and acute respiratory distress syndrome (ARDS) are 2 critical care syndromes that share several features. Both are common, highly lethal, and negatively impact survivors dramatically [1-5] . Intense investigation into both syndromes has resulted in little success in randomized controlled trials as well [6,7] . Sepsis carries an estimated incidence of ARDS of more than 40% in some studies and is a leading cause of death in ARDS [8-10] . Finally, the clinical care and trajectory set forth at the most proximate time of presentation (eg, the emergency department and early intensive care unit ) are now recognized as increasingly impactful periods with respect to overall outcome [11,12] .
Cardiac dysfunction is a prominent feature of sepsis, with an incidence as high as 60% [13] . Sepsis-associated cardiac dysfunction has been described for decades[14,15] . Although the characterization and pathophysiology remain incompletely understood, it typically is described as involving biventricular dysfunction, decreased ejection fraction (EF), and ventricular dilation (eg, increased end-diastolic volume index), which is reversible in survivors over the course of 7 to 10 days [14,16-20] . Earlier studies showed a seemingly paradoxical association with decreased cardiac function and survival, although more recent data question this association [13,14,21-23] . Although sepsis-associated cardiac dysfunction has not definitively been linked with worse outcome, critically ill mechanically ventilated patients (including those with ARDS) have worse outcome associated with nonpulmonary organ failure, including cardiovascular dysfunction [17,23-26] . It is possible that cardiac dysfunction may carry a more deleterious impact in sepsis patients who are mechanically ventilated and those with ARDS, but this has not been extensively investigated.
There is increasing interest in optimizing the care of mechanically ventilated patients early in the course of respiratory failure. This includes preventing and mitigating the severity of ARDS after ICU admission [27-29] . The event rate for ARDS after admission from the ED ranges from 6.2% to 44% [12,30] . Recent data suggest that close to 9% of mechanically ventilated patients have ARDS while in the ED, and around 30% of mechanically ventilated ED patients with severe sepsis will progress to ARDS [31-33] . However, some of these data excluded potential ARDS patients on the assumption of left atrial hypertension in the presence of an elevated B-type...