Evaluation of a recruitment maneuver with positive inspiratory pressure and high PEEP in patients with severe ARDS

Background: To evaluate the effect of a recruitment maneuver (RM) with constant positive inspiratory pressure and high positive end-expiratory pressure (PEEP) on oxygenation and static compliance (Cs) in patients with severe acute respiratory distress syndrome (ARDS). Methods: Eight patients with ARDS ventilated with lung-protective strategy and an arterial partial pressure of oxygen to inspired oxygen fraction ratio (PaO(2)/FIO(2)) less than or equal to100 mmHg regardless of PEEP were prospectively studied. The RM was performed in pressure-controlled ventilation at FIO(2) of 1.0 until PaO(2) reached 250 mmHg or a maximal plateau pressure/PEEP of 60/45 cmH(2)O was achieved. The RM was performed with stepwise increases of 5 cmH2O of PEEP every 2 min and thereafter with stepwise decreases of 2 cmH2O of PEEP every 2 min until a drop in PaO(2) >10% below the recruitment PEEP level. Data was collected before (preRM), during and after 30 min (posRM). Results: The PaO(2)/FIO(2) increased from 83 +/- 22 mmHg preRM to 118 +/- 32 mmHg posRM (P = 0.001). The Cs increased from 28 +/- 10 ml cmH2O(-1) preRM to 35 +/- 12 ml cmH2O(-1) posRM (P = 0.025). The PEEP was 12 +/- 3 cmH2O preRM and was set at 15 +/- 4 cmH2O posRM (P = 0.025). The PEEP of recruitment was 36 +/- 9 cmH2O and the collapsing PEEP was 13 +/- 4 cmH2O. The PaO(2) of recruitment was 225 +/- 105 mmHg, with five patients reaching a PaO(2) greater than or equal to 250 mmHg. The FIO(2) decreased from 0.76 +/- 0.16 preRM to 0.63 +/- 0.15 posRM (P=0.001). No major complications were detected. Conclusions: Recruitment maneuver was safe and useful to improve oxygenation and Cs in patients with severe ARDS ventilated with lung-protective strategy.