Abstract: Postoperative complications after colorectal surgery are important issues affecting patient recovery and quality of life.Recent studies have revealed that gut dysbiosis plays a critical role in the development and progression of these complications.Factors such as surgical trauma,anesthesia,antibiotics,and fasting can lead to reduced microbial diversity,depletion of beneficial bacteria,and enrichment of opportunistic pathogens.Through various mechanisms including activation of Tolllike receptor signaling pathways,alterations in metabolites such as shortchain fatty acids and bile acids,and induction of collagenase secretion by pathogenic bacteria that degrades the extracellular matrix,dysbiosis participates in the pathological processes of postoperative ileus (POI),diarrhea,anastomotic leakage,and low anterior resection syndrome (LARS).Microbiotabased therapeutic strategies include perioperative antibiotic stewardship,probiotic and prebiotic supplementation,metabolitebased interventions,and fecal microbiota transplantation (FMT).Current evidence suggests that rational antibiotic use,perioperative supplementation with specific probiotics,butyrate enemas,and autologous reinfusion of stoma discharge show promise in improving postoperative complications,although some findings remain inconsistent.Future largescale randomized controlled trials are needed to identify specific microbial biomarkers,explore combination therapies,and develop novel microbiotamodulating drugs.

Key words: gut microbiota;colorectal surgery;postoperative complications;microbiota-based interventions