Intestinal failure (IF) is a condition, in which the intestinal function or length remaining is below the minimum amount required for the absorption of sufficient nutrients and fluid to maintain normal life. The nutritional supply of IF depends on the anatomical site, length, and function of the remaining bowel. The goals of nutritional therapy for patients with IF are to achieve bowel adaptation to absorb nutrients sufficiently to live a healthy life with the current intestinal condition, and to promote the enteral autonomy to control nutrient digestion, absorption, excretion, and bowel movement. To stabilize and recover the patient’s nutrition condition after a huge bowel resection, the intestinal rehabilitation team (IRT) for individual nutritional therapy should be established. IRT carefully monitors the changes in body weight, medication use, patient’s symptoms, nutrient deficiency, hydration status, function of the remaining bowel, degree of bowel adaptation, adverse effects due to nutritional therapy, and enteral balance. To achieve intestinal adaptation and enteral autonomy through complicated and difficult nutritional intensive therapy in IF patients, it is essential to manage the patients through multidisciplinary collaboration involving physicians, pharmacists, dietitians, and nurses.

Glutamine is the most abundant amino acid, composed of more than 50 percent of free amino acid in the human body. It had been regarded as a conditional essential amino acid and its concentration is markedly reduced in critically ill patients with trauma, burn, or sepsis. From the early 1990s, many parenteral glutamine studies on critical illness have reported the benefits in mortality, infection, and length of stay. However, its clinical efficacy was based on out-of-date, smaller, single-center studies. Clinical effects of parenteral glutamine have shown no benefits or even harms in recent clinical trials and meta-analysis. Furthermore, it has challenged the hypothesis that low plasma glutamine concentration was associated with poor outcomes in critically ill patients. Although many studies showing the efficacy of glutamine have been reported, parenteral glutamine supplementation may be harmful in patients with multiorgan failure or baseline kidney dysfunction. Further studies should be conducted to identify the use of glutamine supplementation in combination with parenteral and enteral nutrition or enteral/oral nutrition alone, specific adult or pediatric patients, the appropriate time and doses for administration of glutamine, cost-benefit analysis, and the exact mechanisms of action.