1. Department of Anaesthesia; Cairo University; Cairo; Egypt
2. Department of Anaesthesia; Liver Institute; Menoufiya University; Shebeen El Kom; Egypt
3. Department of Community Medicine and Statistics; Liver Institute; Menoufiya University; Shebeen El Kom; Egypt
4. Department of Surgery; Liver Institute; Menoufiya University; Shebeen El Kom; Egypt