The development of a postoperative respiratory insufficiency is typically caused by several factors and include patient-related risks, the extent of the procedure and postoperative complications. Morbidity and mortality rates in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are high. It is important to have consistent strategies for prevention and preoperative conditioning is essential primarily for high-risk patients. Treatment of established postoperative lung failure requires early tracheotomy, protective ventilation (tidal volume 6 ml/kg body weight), elevated positive end expiratory pressure (PEEP, 10-20 mmH2O), recurrent bronchoscopy and early patient mobilization. In critical cases an extracorporeal lung assist is considered to be beneficial as a bridge to recovery and for realizing a protective ventilation protocol. Different systems with separate indications are available. The temporary application of a lung assist allows thoracic surgery to be performed safely in patients presenting with insufficient respiratory function.