1. Department of Anaesthesiology and Resuscitation , Medical University – Pleven , Bulgaria
2. Department of Roentgenology and Radiology , Medical University – Pleven , Bulgaria
3. Department of Orthopedics and Traumatology , Medical University – Pleven , Bulgaria
4. Department of Propaedeutic of Surgical Disease , Medical University – Pleven , Bulgaria
5. Department of Anaesthesiology and Intensive Care , University Hospital – Pleven , Bulgaria