Intestinal Absorption and Enteral Nutrition Support During Critical Illness

Living reference work entry


Malnutrition is common in critical illness and is related to gastrointestinal dysfunction. In critical illness, factors such as starvation, sepsis, reduced mesenteric blood flow, and medications can all contribute to altered gastrointestinal function. Adequate nutritional provision to critically ill is often impeded by delayed gastric emptying and feed intolerance, which is further aggravated by impaired small intestinal absorption of nutrients. In addition to factors that are important to luminal digestion such as gastrointestinal dysmotility and pancreatic insufficiency, recent data indicate that mucosal factors that mediate brush border enzymatic digestion, nutrient transporters, as well as mesenteric blood flow are also affected and adversely influenced by small intestinal nutrient absorption. Currently, timing of initiation of enteral nutrition appears to be important in intestinal absorption as early enteral feeding is associated with increased absorption of carbohydrate, improved mucosal integrity, and better clinical outcomes. This chapter will provide an overview of factors that are responsible for small intestinal malabsorption during critical illness and outline therapeutic strategies to manage and improve energy delivery, nutrient digestion, and intestinal absorption in these patients.


Gastric Emptying Critical Illness Enteral Nutrition Enteral Feeding Intestinal Permeability 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.





Area under the curve


Glucagon-like peptide 1


Glucose transporter


Intensive care unit




Migrating motor complex


Peptide transporter 1


Polypeptide YY


Sodium glucose transporter 1


Superior mesenteric artery


Type 1 taste receptor


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Copyright information

© Copyright Her Majesty the Queen in Right of Australia 2014

Authors and Affiliations

  1. 1.Discipline of Medicine, School of MedicineUniversity of AdelaideAdelaideAustralia
  2. 2.Department of Gastroenterology and HepatologyRoyal Adelaide HospitalAdelaideAustralia

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