1 Department of Intensive Care, Emergency Medicine and Anaesthesiology, Fondazione Policlinico Universitario "Agostino Gemelli"-IRCCS, Largo Francesco Vito, 1, 00168, Rome, Italy. claudio.sandroni@policlinicogemelli.it.
2 Institute of Anaesthesiology and Intensive Care Medicine, Università Cattolica del Sacro Cuore, Rome, Italy. claudio.sandroni@policlinicogemelli.it.
3 1IRCCS Fondazione Don Carlo Gnocch, Florence, Italy.
4 Dipartimento Neuromuscolo-Scheletrico e degli Organi di Senso, SODc Neurofisiopatologia, AOU Careggi, Florence, Italy.
5 Warwick Clinical Trials Unit, University of Warwick, Coventry, UK.
6 Department of Anaesthesia and Intensive Care Medicine, Royal United Hospital, Bath, UK.