1 Anesthesia and Intensive Care Unit, Department of Surgical, Microsurgical and Medical Sciences, University of Sassari, A.O.U Sassari, Sassari, Italy - pterragni@uniss.it.
2 Department of Surgical Sciences, Città della Salute e della Scienza Torino, Turin, Italy.
3 Department of Anesthesia and Critical Care Medicine, Sapienza Università di Roma, Policlinico Umberto I, Rome, Italy.