A patient was operated on account of perforated stomach ulcer, terminal stage of diffuse peritonitisAfter endotoxic shock in the post-operative period the artificial pulmonary ventilation is carried out with inhalation of 60% oxygen. Blood gasses: РаО2 = 70-78 mm Hg, hypoxemia is not diminishing, CVP - 150-180 mm H2O, BP - 90/60 mm Hg (with administering of dopamine in high doses). Radiologically: diffuse pulmonary infiltration. What is the reason of the resistant arterial hypoxemia?