Intensive care is a rapidly changing area of medicine, and after four years from the 2nd edition the volume editors and authors have deemed necessary to update it. In the recent years, in fact, five new randomised controlled trials and five new meta-analyses demonstrate that selective decontamination of the digestive tract [SDD] is an antimicrobial prophylaxis to prevent severe infections of not only lower airways but also of blood. Additionally, SDD has been shown to reduce inflammation including multiple organ failure and mortality. An intriguing observation is the evidence that SDD using parenteral and enteral antimicrobials reduces rather than increases antimicrobial resistance. Moreover, a new chapter on microcirculation had been added.