Sepsis is a challenging condition: the high prevalence and the complexity of its clinical presentation lead to high morbidity and mortality. The most updated definition of sepsis and septic shock, Sepsis-3 introduced in 2016, changed the previous paradigm and highlighted the importance of the pathophysiological alterations and their prognostic implications. Sepsis is defined as a dysregulated inflammatory response to an infection, which leads to organ dysfunction, while septic shock is defined as a subset of sepsis in which underlying circulatory and cellular metabolism abnormalities are profound enough to substantially increase mortality [1].