Assessing risk and treatment responsiveness in ARDS: Beyond Physiology

Defining the severity of ARDS using PaO2/FIO2 , 150 as a surrogate for life-threatening edema is a promising approach. However, ARDS is a heterogeneous syndrome, and identifying a treatment-responsive hyperinflammatory subtype across the PaO2/FIO2 severity spectrum suggests the fundamental limitations of using physiological or anatomic variables alone to understand and treat the underlying mechanisms that lead to ARDS, let alone to stratify risk. We suspect that both approaches will be complementary and will require prospective evaluation for their predictive enrichment potential