Feasibility Study of the Hemolung Respiratory Assist System (Germany)

The objective of the feasibility study is to evaluate the safety and efficacy of the Hemolung RAS in patients with hypercapnic respiratory failure in five groups of patients: Group 1: COPD patients with an acute exacerbation and have a 50% likelihood of failure of noninvasive positive pressure ventilation (NIPPV) leading to intubation and mechanical ventilation Group 2: Patients with hypercapnic respiratory failure on invasive mechanical ventilation who have either: * Failed two or more weaning attempts OR * Failed one or more weaning attempts and do not wish to be invasively mechanically ventilated. Group 3: Patients with hypercapnic respiratory failure on noninvasive positive pressure ventilation who have failed two weaning attempts and do not wish to be invasively mechanically ventilated. Group 4: Patients with hypercapnic respiratory failure who in the view of the treating physician are declining on optimized non-invasive positive pressure ventilation OR demonstrate a complete intolerance of non-invasive positive pressure ventilation for any reason and invasive mechanical ventilation is considered undesirable by the treating physician. Group 5: Patients who are currently invasively mechanically ventilated and in the view of the treating physician would benefit from the application of protective lung ventilation, and in whom this cannot be achieved without significant worsening of respiratory failure.