Prior to the surgery for anal fistula, a cleansing enema will be given to the patient at 4-5 o’clock in the morning of the surgery, and a few open cures or Pfizer to promote the excretion of stool will be prescribed so that the patient can get rid of the stool. The benefit is that it will prevent the stool from being discharged down from the upper section during the surgery and will contaminate the surgery. Some hospitals require a day of fasting after endoanal fistula surgery, and if the bowel is cleared, the patient will not have a strong feeling of bowel movement for a day. If you don’t clean the bowel, the stool may push down from the top and there will be a strong feeling of defecation, which will irritate and contaminate the wound, and the feeling of defecation cannot be suppressed.