<prompt> Acute Lung Injury ALI is characterized by all exceptPaO2FiO2 200mm HgBilateral interstitial infiltratesPCWP 18 mm HgNormal Left atrial pressure  <response>: Acute lung injury ALI is a less severe disorder but has the potential to evolve into ARDS. The aerial PaO2 in mmHgFIO2 inspiratory O2 fraction 200 mmHg is characteristic of ARDS, while a PaO2FIO2 between 200 and 300 identifies patients with ALI who are likely to benefit from aggressive therapy.Ref: Harrisons 18e p2205, 17e p1680 