A panel of experts came together in Berlin last year and worked to make an ARDS definition that was more specific. ALI no longer exists. Now there is mild, moderate and severe ARDS defined by the PF ratios.
The ARDS Conceptual Model. The panel agreed that ARDS is a type of acute dif- fuse, inflammatory lung injury, lead- ing to increased pulmonary vascular permeability,increasedlungweight,and loss of aerated lung tissue. The clini- cal hallmarks are hypoxemia and bilat- eral radiographic opacities, associated with increased venous admixture, in- creased physiological dead space, and decreased lung compliance. The mor- phologicalhallmarkoftheacutephase is diffuse alveolar damage (ie, edema, inflammation, hyaline membrane, or hemorrhage).29