Perioperative Modulation of the Gut-Liver Axis in Liver Surgery: Clinical Evidence and Future Directions

Liver resection and liver transplantation remain cornerstone treatments for many hepatobiliary diseases, yet postoperative infection, impaired liver regeneration, and post-hepatectomy liver failure (PHLF) remain serious complications. Perioperative stressors can disrupt the gut-liver axis by altering the intestinal microbiota, epithelial barrier integrity, microbial metabolites, bile acid signaling, and host immunity. This review examines how these alterations relate to clinical outcomes and evaluates evidence for microbiota-targeted interventions, including probiotics, synbiotics, nutritional optimization, antibiotic stewardship, bile acid modulation, and emerging multiomics strategies. We distinguish liver resection from living-donor and deceased-donor liver transplantation because the patient populations, graft or remnant anatomy, ischemia-reperfusion exposures, immune status, and outcome definitions differ. Clinical evidence most consistently supports selected pro-/synbiotic strategies for reducing postoperative infection in higher-risk settings, whereas microbiome-based prediction of PHLF, fecal microbiota transplantation (FMT), bile acid-directed therapy, and precision multiomics-guided pathways remain investigational. Future work should use transparent literature identification, standardized perioperative protocols, risk-defined populations, external validation, and prospective multicenter trials. A better understanding of gut-liver interactions may help preserve beneficial host-microbial signals while limiting translocation and inflammation during recovery.