This multicenter, randomized, double-blind, placebo-controlled clinical trial aimed to investigate the efficacy and safety of gut oxygen therapy in the treatment of ischemic-hypoxic bowel disease using deep intestinal catheterization as a targeted route for gut oxygen delivery.

Subjects who met the inclusion criteria but did not meet any of the exclusion criteria were randomly assigned in a 1:1 ratio to receive 250mL of oxygen (30%-40%) or air through a deep intestinal catheterization four times a day for 5 days. The data of core symptoms (abdominal pain, abdominal distension, defecation), intestinal motility, vital signs and test results before and after treatment were collected to evaluate the efficacy and safety of gut oxygen therapy.

Inclusion Criteria:

• Clinical diagnosis of intestinal ischemia and hypoxia-related diseases caused by conditions such as ischemic bowel disease, heart failure, etc., presenting with recurrent or persistent abdominal pain and/or distension, and difficulty in defecation. Examples include: heart failure-related defecation difficulty, severe malnutrition combined with defecation difficulty, acute ischemic bowel disease, and chronic ischemic bowel disease.
• At least able to perform bedside activities and able to defecate in conventional positions (sitting or squatting).
• Age ≥18 years, and able to voluntarily sign informed consent.

Exclusion Criteria:

• Acute intestinal emergencies such as acute intestinal obstruction, intestinal perforation, or active massive gastrointestinal bleeding.
• Intestinal fistula.
• History of abdominal surgery within the recent past (<1 month).
• Severe uncontrolled arrhythmia or respiratory failure.
• Cardiac function Class IV (NYHA Class IV).
• Patients with abnormal visceral pressure sensitivity.
• Inability to cooperate with study assessments.
• Other conditions that, in the opinion of the investigator, make the subject unsuitable for inclusion.