HP and acute respiratory distress syndrome: Analogously, the two groups discriminated by the first Hp cutoff value differed significantly in baseline characteristics BMI, CCI, SOFA, SAPS, and APACHE scores at ARDS onset as well as ARDS etiology, pH, and pulmonary compliance at ECMO initiation, incidence of septic shock, RRT, number of transfused PRBCs, lactate levels, and therapy with inhaled nitric oxide (Table 2).