title: Perioperative nutritional management in digestive tract surgery.
abstract: OBJECTIVE
  This article reviews the recent research on perioperative nutrition in digestive tract surgery in the light of modern perioperative care principles, that is, enhanced recovery after surgery (ERAS). Four major directions of research emerge: detecting malnutrition, perioperative hyperglycemia/insulin resistance, enteral/parenteral nutrition and immunonutrition.
  
  
  RESULTS
  For preoperative nutritional screening/assessment, current data cannot single out superiority for SGA questionnaire, nutritional risk score, Reilly's nutritional risk score or nutritional risk index in the ability to predict nutrition-related complications. The use of ERAS elements to reduce surgical stress and preclude postoperative insulin resistance has recently been clearly linked to reductions in adverse outcomes. There are specific situations in which enteral nutrition is contraindicated and criterias for preoperative and postoperative parenteral nutrition in undernourished patients are defined in guidelines recently available. Several controlled randomized studies and systematic reviews indicate that immune nutrition formulas reduce both morbidity and length of stay after major abdominal surgery.
  
  
  CONCLUSIONS
  To reduce surgical stress, insulin resistance, unnecessary protein losses and postoperative complications, the use of an ERAS protocol is important. Current data shows that the use of perioperative immunonutrition diets for major abdominal surgery is beneficial. Further research on nutritional assessment tools to predict who is at risk for postoperative complications is needed.
authors.affiliation: Department of Surgery, Ersta Hospital, Stockholm, Sweden. ulf.gustafsson@erstadiakoni.se
authors.forename: Ulf O
authors.initials: UO
authors.lastname: Gustafsson
authors.forename: Olle
authors.initials: O
authors.lastname: Ljungqvist
mesh_terms: D013505:Digestive System Surgical Procedures; D041981:Gastrointestinal Tract / Q000276:immunology / Q000601:surgery*; D006801:Humans; D006943:Hyperglycemia / Q000517:prevention & control*; D007333:Insulin Resistance; D044342:Malnutrition / Q000517:prevention & control*; D015596:Nutrition Assessment; D044623:Nutrition Therapy; D018529:Nutritional Support; D019990:Perioperative Care; D011183:Postoperative Complications / Q000276:immunology / Q000517:prevention & control*; D013312:Stress, Physiological