Gut microbiota changes and enteric therapies in critically ill patients: a narrative review

Abstract

Gut microbiota are closely related to host metabolism and immunity. When the host is severely invaded, a rapid change occurs in which the number and the proportion of resident bacteria decrease and pathogenic bacteria increase in the gut. This change also induces bacterial translocation and changes in immune function, which cause systemic inflammation originating from the intestinal tract. To ameliorate these effects, enteric therapies such as selective digestive decontamination, probiotics or synbiotics therapy, and fecal microbiota transplantation have been performed on critically ill patients. There are also expectations for new intestinal treatments that target gut microbiota, such as bacterial cocktail therapy and phage therapy. This review outlines the relationship between the gut microbiota and the host, describes the characteristics of the gut microbiota of critically ill patients, and summarizes the current status and prospects of enteric therapies.