Integrating gut‑brain axis insights into bundled nutrition care for critically ill patients: From mechanisms to implementation (Review)

Critical illness induces a marked disruption of the gut‑brain axis, which is characterized by systemic inflammation and the rapid collapse of intestinal barrier integrity. These pathological shifts facilitate the translocation of pathogen‑associated molecular patterns, thereby driving neuroinflammation and exacerbating intensive care unit‑acquired syndromes such as delirium and muscular wasting. Although conventional nutritional strategies emphasize caloric and protein goals, emerging evidence has highlighted the necessity of modulating the host‑microbiome interface to preserve neurological and systemic homeostasis. The integration of fermentable fibers, probiotics and specialized lipid mediators into a standardized framework may effectively interrupt the self‑perpetuating cycle of dysbiosis and organ failure. The present review uniquely contributes to the field by integrating an implementation science framework for clinical bundle application and discussing artificial intelligence driven precision nutrition advances, which are topics that have not been comprehensively covered in the majority of previous reviews. Therefore, the present review bridges mechanistic insights with practical, scalable strategies to optimize nutritional care and improve recovery trajectories in patients with critical illness.