 Patients will be randomized by weeks admitted and the patients in the gum chewing group intervention group will chew one stick of gum the first post-operative day, after the nasogastric tube is removed or if they patient does not have a nasogastric tube, with the head of bed elevated a minimum of 30 degrees for 30 minutes, three times a day at set intervals: 0900, 1400, and 2100. The gum will be kept in the Accudose cabinet and distributed by the medication nurse. The gum chewing regimen will continue until the first bowel movement. All patients in the non-intervention group will receive standard preoperative and postoperative regimens. 