Enteral Nutrition and NIL Per OS Rules Priorto Elective Surgery

ENTERAL NUTRITION AND NIL PER OS RULES PRIORTO ELECTIVE SURGERY

Long before the recognition by Mendelsohn of the problem posed by aspiration pneumonitis, anesthe-siologists were reluctant to anesthetize patients scheduled for elective surgery if they had not been fasted overnight. Over time, the duration of obliga-tory time of no solid food per os has steadily declined,particularly in infants and young children. In the patient with critical illness, discontinuingan EN infusion may require multiple potentially dangerous adjustments in insulin infusions and maintenance of intravenous fluid rates. Meanwhile, the evidence is sparse that EN infusions delivered through an appropriately sited gastrointestinal feed-ing tube increases the risk of aspiration pneumoni-tis. It is also relatively easy to empty the stomach immediately prior to anesthesia and surgery using 5–10 minutes of intermittent suction through a nasogastric tube. Therefore, current guidelines and current published evidence support continuing EN infusions (particularly when they are delivered dis-tal to the pylorus) perioperatively and intraopera-tively. Similarly, allowing preoperative patients to consume clear liquids, as desired, up to the time of surgery seems to have no influence on the risk of adverse outcomes from aspiration pneumonitis. Moreover, there is abundant evidence that adminis-tering a preoperative carbohydrate “load” to nondia-betic patients shortly before surgery will have the salutary metabolic effect of increasing plasma insu-lin concentrations and decreasing postoperative insulin resistance. Such preoperative carbohydrate loading is not nearly as commonplace as we believe it should be.