Laparoscopic radical prostatectomy is becoming a widely used surgical procedure because it carries some important advantages over open prostatectomy. This surgical technique requires positioning the patient at 25-40 degree head-down position (steep trendelenburg) for a prolonged time in association with pneumoperitoneum at 12-15 mmHg. The postural change from supine to head down position causes a hydrostatic fluid shift towards the head and the thorax, thus increasing venous return and stimulating the cardiopulmonary baroreceptors. Moreover, there are reports of severe bradycardia and cardiac arrest following pneumoperitoneum in association with steep trendelenburg. A vagal hypertone induced by the combination of these two factors, or sympathetic hyperactivity elicited by pneumoperitoneum insufflation have been alternatively advocated as a cause of such hemodynamic changes. However these speculations are little more than a narrative role because any evidence based demonstration is never been provided.