(1) Critical type of COVID-19 according to COVID-19 diagnosis and treatment guidelines in China (7th edition), (2) Gastrointestinal perforation, (3) Gastrointestinal obstruction, (4) Recent history of intestinal fistula, (5) Disturbance of consciousness, (6) Gastrointestinal hemorrhage, (7) Malignant tumors, (8) Pregnant or lactating women.

(1) Critical type of COVID-19 according to COVID-19 diagnosis and treatment guidelines in China (7th edition), (2) Gastrointestinal perforation, (3) Gastrointestinal obstruction, (4) Recent history of intestinal fistula, (5) Disturbance of consciousness, (6) Gastrointestinal hemorrhage, (7) Malignant tumors, (8) Pregnant or lactating women.