High-risk Patients With Pancreatic Exocrine Insufficiency

The goal of this clinical trial is to systematically evaluate whether peptide-type enteral nutrition (EN) formulations improve protein uptake efficiency in high-risk groups at ICU PEI, using targeted amino acid metabolomics and gut microbiota co-metabolomics as core quantitative indicators. Researchers will compare protein absorption efficiency of short-chain peptide and complete protein enteral nutrition formulas in high-risk populations for PEI in the ICU Participants will: Enteral nutrition was administered for ICU critically ill patients with high-risk factors for PEI