Define Immediate Preoperative Period during Surgery?

Nothing should be given by mouth for at least 8 hours before a general surgery so that the stomach has no leftover food at the time of surgery. In case of emergency surgery, gastric suction is used to remove the food if the patient has recently eaten a meal. This is important because food in the stomach may be vomited or aspirated during the surgery or during recovery soon after the surgery. It may also interfere with the surgery itself if it is related to the abdomen or gastrointestinal tract. In such cases a low residue or residue free diet is given several days before the surgery to clear the operative site. Elemental or chemically defined formulas are given either orally or through tube feeds.