Sepsis related with nosocomial infection, IMV application and the duration thereof, PaO2/FiO2, APACHE II on admission to ICU, SOFA scores (on admission to ICU and on the 3rd day), CRP values (initial, 3rd day, and ∆ CRP) were used to form a multi-logistical regression model. Here, CRP is linked to nosocomial infection.