Recent literature suggests that the incidence of ARDS in intubated ED patients may be as high as 10%.
The Berlin Definition of ARDS includes the acute onset of bliateral opacities (CXR or chest CT) that is not fully explained by pulmonary edema or fluid overload.
Emergency physicians and Intensivists are well versed in lung-protective ventilator settings for patients with ARDS.
However, several diseases can appear simliar to ARDS and may require different ventilator strategies and treatments.
In the absence of clinical risk factors for ARDS (e.g., sepsis, trauma), consider the following in your differential:
Idiopathic pulmonary fibrosis
Interstitial pneumonitis
Granulomatosis with polyangitis (Wegener's)
Diffuse alveolar hemorrhage
Goodpasture's syndrome
References
Guerin C, et al. The ten diseases that look like ARDS. Intensive Care Med 2015; 41:1099-1102.