Longitudinal Plasma Metabolomics by GC–MS and LC–MS During Total Parenteral Nutrition After Gastrointestinal Surgery

Overall, the results demonstrated a distinct longitudinal metabolomic pattern characterized by increases in circulating amino acids and time-dependent changes in carbohydrate- and lipid-related metabolites within the first 72 h of TPN. This exploratory, time-resolved metabolomic study in 37 patients highlights the utility of untargeted metabolomics for characterizing early metabolic adaptation to parenteral nutrition and supporting postoperative metabolic monitoring.