To promote a better gas-exchange, the patient with ARDS will be mechanically ventilated. This can be aggressive and harmful for the lungs. With the use of an extra-corporeal CO2-remover, CO2 can be removed so that the mechanical ventilation setting will be less aggressive and will decrease lesions in the lung. The veno-venous extracorporeal CO2-remover pumps blood from a vein via a catheter through an oxygenator (gas exchanger that adds oxygen to the blood and extracts carbon dioxide from the blood) and back into a vein.