1. Critical Care and Pain Management Department, Faculty of Medicine, Cairo University, Cairo, Egypt
2. Surgical ICU and Pain Management Department, Theodor Bilharz Research Institute, Giza, Egypt
3. Surgical ICU and Pain Management Department, Kasr Al-Ainy Hospital, Cairo, Egypt
4. Specialist of Anesthesiology, Surgical Intensive Care and Pain Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt