[Veno-venous extracorporeal support to treat acute respiratory distress syndrome: Rationale and clinical objectives]

Extracorporeal circulation techniques can be used for the management of severe respiratory failure complicating the acute respiratory distress syndrome with three objectives: 1) to ensure satisfying oxygenation by bypassing the sick lung using a veno-venous circulation with high blood flows; this technique easily extracorporeal permit CO₂ elimination; 2) to ensure partial elimination of CO₂ with the aim to protect the lungs from risky mechanical ventilation. Four to five times lower blood flows are sufficient with a veno-venous circulation or pumpless arterio-venous techniques; 3) associated cardiac failure may exceptionally require veno-arterial extracorporeal circulation. Physiological studies and clinical trials are absolutely needed to better delineate the indications of these techniques.