How to ventilate patients without acute respiratory distress syndrome?

PURPOSE OF REVIEW: There is convincing evidence for benefit from lung-protective mechanical ventilation with lower tidal volumes in patients with the acute respiratory distress syndrome (ARDS). It is uncertain whether this strategy benefits critically ill patients without ARDS also. The present article summarizes the background and clinical evidence for ventilator settings that have the potential to protect against ventilator-induced lung injury. RECENT FINDINGS: There has been a paradigm shift from treating ARDS to preventing ARDS. In surgical patients, anesthesiologists should consider ventilating patients with a tidal volume of 6-8 ml/kg predicted body weight (PBW), levels of positive end-expiratory pressure (PEEP) between 0 and 2 cmH(2)O, and higher levels of FiO(2). Finally, in critically ill patients without ARDS, intensive care physicians could consider ventilating with a PEEP level of 5 cmH(2)O and lower levels of FiO(2). There is insufficient evidence for the benefit of lower tidal volumes in these patients. There is, however, some evidence that tidal volumes of 6 ml/kg PBW or less are associated with better outcomes. SUMMARY: There is increasing and convincing evidence that the use of lower tidal volumes during mechanical ventilation of patients without ARDS prevents against ventilator-induced lung injury.