Efficacy of Fecal Microbiota Transplantation in ICU Patients With Gastrointestinal Dysfunction-induced Enteral Nutrition Intolerance

Inclusion criteria: 1. 8 ≤ age ≤ 70 years old, any nationality, any gender; 2. Female patients have no potential fertility (i.e., no physical ability to conceive, including women who have been menopausal for 2 years) or no pregnancy plan; 3. Patients who have been in the ICU for at least 24 hours; 4. Patients with an expected ICU stay of at least 7 days; 5. Non-acute patients with at least one manifestation of gastrointestinal dysfunction leading to enteral nutrition intolerance; 6. Patients can cooperate or passively complete the relevant examination and complete the follow-up; 7. Informed consent is documented by means of a written, signed and dated informed consent form. Exclusion Criteria: 1. Severe systemic infection, in early recovery period, hemodynamic instability or tissue hypoperfusion, severe imbalances in water and electrolyte status; 2. Patients who are considered by clinicians to be at high risk of death within 5 days, or who are subject to restricted treatment decisions; 3. Severe damage of intestinal barrier such as active massive bleeding and perforation of digestive tract; 4. Patients who cannot tolerate 50% of caloric calorie requirements with enteral nutrition due to severe diarrhea, significant fibrous intestinal stenosis, severe gastrointestinal bleeding, high-flow intestinal fistula and other reasons; 5. Nasal jejunal tube cannot be placed; 6. Planned or recent abdominal surgery (within 14 days); 7. Currently diagnosed with fulminant colitis or toxic megacolon; 8. Neutropenia (neutrophil count \< 1500 /µL); 9. Patients with congenital or acquired immune deficiency; 10. Malignant hematologic diseases, such as lymphoma; 11. Autoimmune diseases; 12. Patients who have recently received high-risk immunosuppressive or cytotoxic drugs, such as rituximab, doxorubicin, or medium-high dose of steroid hormones (20mg/day or higher) for more than 4 weeks; 13. Pregnant or lactating women; 14. Participating in other clinical studies as a participant at the time of enrollment or within 3 months before inclusion; 15. Informed consent can not be obtained.