2 Department of Anaesthesia, Intensive Care and Emergency Medical Services, Ospedale Maggiore, Bologna, Italy. Electronic address: F.Semeraro@118er.it.
3 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
4 EMS 118 Dispatch Center, Ospedale Maggiore, Bologna, Italy.
5 Fondazione Policlinico Universitario A. Gemelli, IRCCS, Institute of Anaesthesia and Intensive Care, Catholic University of the Sacred Heart, Rome, Italy.
6 Department of Emergency, Ospedale Maggiore, Bologna, Italy.