1. Minimally Invasive and Robotic Thoracic Surgery, Surgical, Medical, Molecular, and Critical Care Pathology Department, University Hospital of Pisa, 56124 Pisa, Italy
2. Section of Statistics, University Hospital of Pisa, 56124 Pisa, Italy
3. Cardiothoracic and Vascular Anaesthesia and Intensive Care, Department of Anaesthesia and Critical Care Medicine, University Hospital of Pisa, 56124 Pisa, Italy