Thanks for the modern mechanic ventilation, the advanced nursing monitoring system has been constantly growing in order to reduce the risk of VILI (Ventilator Induced Lung Injury); Under these circumstances the nursing responsibility for the correct respiratory monitoring in intensive care unit is essential. Despite the fact that scientific evidence has been questioning the esophageal pressure monitoring for the management of patients mechanically ventilated, in my professional experience I have had the opportunity to learn about the correct use of this device, which has proved to be very useful in the reduction of VILI. The aim of this project is to discuss the actual efficacy of this monitoring system and to highlight the preparatory criteria to validate the very one; in other words, I want to prove the graphical bases of Pes (Esophageal Pressure) intensive care unit nurses have to be aware of