[Ventilation in the prone position in acute respiratory distress syndrome (ARDS)]

Prone position mechanical ventilation (PPV) secures an improvement in gas exchange in approximately two-thirds of ARDS patients. Recent experimental and clinical data suggest that PPV acts mainly by recruiting alveoli situated in the dorsal dependent regions which are collapsed under the superimposed weight of the overlying edema-laden lungs. The purpose of this article is to provide an overview of the basic pathophysiological mechanisms underlying PPV as well as to underscore the promising clinical results so far obtained with this technique. In spite of these results the place of PPV among the other ventilatory and pharmacological approaches in the supportive treatment of ARDS, and the possible beneficial or deleterious consequences of associating PPV with one or more of these therapeutic modalities, remains to be determined.