Dirk Van Raemdonck1, Arne Neyrinck2. 1. Department of Thoracic Surgery, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium. Electronic address: dirk.vanraemdonck@uzleuven.be. 2. Department of Anaesthesiology, University Hospitals Leuven, Leuven, Belgium.