[1] S Maria Hosp, Dept Anesthesia, Intens Care Unit, Terni, Italy
[2] Univ Aquila, Dept Life Hlth & Environm Sci, Laquila, Italy
[3] Fabrizio Spaziani Hosp, Dept Anesthesia, Intens Care Unit, Frosinone, Italy
[4] SAMO Pain Management Ctr, Rome, Italy
[5] Univ Padua, Inst Human Anat, Dept Neurosci, Padua, Italy
[6] Univ Perugia, Dept Med & Surg, Perugia, Italy
[7] SS Filippo & Nicola Acad Hosp, Dept Anesthesia & Intens Care Unit, Laquila, Italy