A common gastrointestinal problem that can occur with any abdominal surgery is an ileus, which is a temporary stoppage of your bowel functions. This usually occurs after abdominal surgery either due to either the anesthesia, or other medications, or because of your bowel being was touched and/or moved during the surgery.
The bowels are actually your intestines, which begin at the end of the stomach and end at the anus. If your bowel function slows temporarily after the procedure, you will be given clear liquids until your bowel function returns. The passage of gas usually signifies normal bowel functions. In very rare cases, the ileus may need to be treated with a tube in the stomach, or by a second surgery.