<prompt> Theoretical Optimal PEEP in ARDS is0 - 5 mm Hg5 - 12 mm Hg12 - 15 mm Hg15 - 18 mm Hg  <response>: In most clinical settings, positive end-expiratory pressure PEEP is empirically set to minimize Fio2 inspired O2 percentage and maximize Pao2 aerial paial pressure of O2. On most modern mechanical ventilators, it is possible to construct a static pressure-volume curve for the respiratory system. The lower inflection point on the curve represents alveolar opening or recruitment. The pressure at this point, usually 12-15 mmHg in ARDS, is a theoretical optimal PEEP for alveolar recruitment.Ref: Harrison 19e pg: 1738 