[1] Univ Vita Salute San Raffaele, San Raffaele Hosp, Dept Surg, Via Olgettina 60, I-20132 Milan, Italy
[2] Univ Vita Salute San Raffaele, Hosp San Raffaele, Dept Anesthesiol, I-20132 Milan, Italy
[3] Cuneo Hosp, Dept Surg, Chicago, IL USA
[4] Humanitas Hosp Milan, Dept Surg, Milan, Italy
[5] Humanitas Hosp Milan, Dept Anesthesiol, Milan, Italy
[6] Legnano Gen Hosp, Dept Surg, Legnano, Italy
[7] Legnano Gen Hosp, Dept Anesthesiol, Legnano, Italy
[8] Cottolengo Hosp Turin, Dept Surg, Turin, Italy
[9] Prato Hosp, Dept Surg, Prato, Italy
[10] Casa Cura Citta Udine, Dept Surg, Udine, Italy
[11] Cantu Hosp, Dept Surg, Cantu, Italy
[12] Candiolo Hosp, Dept Surg, Turin, Italy
[13] Luigi Sacco Hosp, Dept Surg, Milan, Italy
[14] Mauriziano Hosp Turin, Dept Surg, Turin, Italy
[15] San Paolo Hosp, Dept Surg, Sao Paulo, Brazil
[16] Univ Florence, Careggi Hosp, Dept Surg, Florence, Italy