1. Geriatric Surgery, Department of Surgical Science, L'Aquila University, L'Aquila, Italy
2. Day Surgery Unit, Pescina Hospital, L'Aquila, Italy
3. Department of Medicine and Public Health, L'Aquila University, L'Aquila, Italy
4. Clinical Pathology Unit, Pescina Hospital, L'Aquila, Italy
5. Blood Transfusion Unit, Avezzano Hospital, L'Aquila, Italy