1. Department of Thoracic Surgery, HELIOS University Hospital Wuppertal, University Witten/Herdecke, Wuppertal, Germany
2. Intensive Care Medicine, HELIOS University Hospital Wuppertal, University Witten/Herdecke, Wuppertal, Germany
3. Division of Pulmonary, Critical Care and Occupational Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA