Cálculo da pressão expiratória positiva final ideal incremental e decremental com utilização do método de Suter Calculating ideal decremental and incremental positive end-expiratory pressure using

The application of positive end-expiratory pressure (PEEP) constitutes the most effective support therapy for acute respiratory distress syndrome (ARDS). Originally described by Suter, the PEEP compliance method proposes to optimize PEEP used by measuring the static compliance (Cst), which can achieve an ascending and a descending curve. This present study aimed to compare incremental and decremental phases of PEEP compliance method, in order to evaluate the ideal PEEP in ARDS patients. Thirty-three patients with ARDS criteria sedated and paralyzed were subjects of this study. After alveolar recruitment maneuver were submitted to the PEEP calculation. To the incremental PEEP (PEEPi) calculation, it started with 6 cmH2O; increasing 2 cmH2O in each 5 respiratory cycles, until a 20 cmH2O PEEP or a plateau pressure ≥ 45 cmH2O was reached. The decremental PEEP (PEEPd) calculation proceeded the same way, until 6 cmH2O. In both phases, the ideal PEEP would be the one which caused the best Cst. The PEEPi and PEEPd mean values were, respectively, 12.97 ± 4.32 cmH2O and 12.90 ± 3.84 cmH2O; the Csti and Cstd mean values were 40.09 ± 17.32 mL/cmH2O and 40.77 ± 16.52 mL/cmH2O. The Student t test analysis to paired samples did not show significative differences when comparing PEEPi versus PEEPd and Csti versus Cstd (p > 0.05). The Pearson’s correlation, both to PEEP and Cst values, showed strong dependence between the variables, therefore, the superiority of one of the method’s phase over another cannot be demonstrated.