Extracorporeal CO2 removal is a low-flow technique in which a pump, a membrane lung and sweepgas, remove CO2 from a patient. This facilitates protective, invasive ventilation in patients with severe hypercapnia, for example in ARDS. Although the physiological concept has been proven many times, the indication area has remained limited to only seriously ill, highly complex patients. Because of this and the relatively high number of contraindications and complications, the use of this technique is limited to Intensive Care.