[1] GiViTI Coordinating Ctr, Lab Epidemiol Clin, Ist Ric Farmacol Mario Negri, Ranica, Bergamo, Italy
[2] Univ Brescia, Ist Anestesia & Rianimaz, Spedali Civili, Brescia, Italy
[3] Osped Maggiore, Policlin IRCCS, Ist Anestesia & Rianimaz, Milan, Italy
[4] Osped Civile, Serv Anestesia & Rianimaz 1, Legnano, Milano, Italy