Fig. 1.

The procedures of (Modified) de-escalation interventions in period 2 and 3. Patients were active surveillance culture (ASC) for pathogens colonization and infection twice a week when admitted to the ICU, and assesse the risk factors of MDR bacteria colonization and infection immediately. For patients were defined infection/colonization with MDR pathogens, or came from clinical department with high prevalence of MDR bacteria before admitted to ICU, with invasive devices and damaged skin barrier such as endotracheal intubation, central venous catheter and urinary catheter etc., first level interventions measures were taken. For patients came from clinical department with low detection rate of MDR bacteria and just infected/colonized with common pathogens before admitted to ICU, second level interventions were taken. However, patients without bacteria infection/colonization or high risk factors, simple third level interventions were implemented. When patients in first level interventions have 2 consecutive negative tests which should be carried out over at least 1 week, descend to second level interventions. When continuous twice ASC negative results for second level patients, descend to third level interventions, and upgrade to first level interventions once MDR bacteria was detected during their ICU stay