The reason why the catheter should be inserted little by little is to prevent damage to the intestinal mucosa, to prevent the patient from experiencing discomfort and to understand the location of the intestinal obstruction. 1. Prevent damage to the intestinal mucosa: the catheter of intestinal obstruction should be inserted little by little in order to prevent the catheter from damaging the intestinal mucosa in the process of insertion, otherwise it will easily cause bleeding and infection, and in serious cases, it may also induce enteritis, which will aggravate the condition. 2. Prevent patients from discomfort: patients will feel uncomfortable when the catheter for intestinal obstruction is inserted, inserting it little by little is to let the patients adapt to it better, and to prevent patients from experiencing abdominal pain, dyspnea and other discomforts. 3. Understanding the location of intestinal obstruction: The little bit of insertion of intestinal obstruction catheter is to better understand the location of intestinal obstruction, so as to facilitate the catheter to be placed in the appropriate position, open the airway, and release the obstruction. When inserting a catheter for intestinal obstruction, it needs to be operated by a professional doctor. Please choose a regular medical institution to avoid delaying your condition when discomfort occurs.