1. Department of Cardiothoracic Anaesthesia, Cardiovascular Centre E. Malan, University of Milan, Istituto Policlinico S. Donato, Milan, Italy,
2. Department of Cardiothoracic Anaesthesia, Cardiovascular Centre E. Malan, University of Milan, Istituto Policlinico S. Donato, Milan, Italy
3. Department of Cardiovascular Perfusion, Cardiovascular Centre E. Malan, University of Milan, Istituto Policlinico S. Donato, Milan, Italy