Enteral tube nutrition is indicated for patients who have a functioning gastrointestinal GI tract but cannot ingest enough nutrients orally because they are unable or unwilling to take oral feedings. See also Overview of Nutritional Support. Compared with parenteral nutrition , enteral nutrition has the following advantages:. Severe protein-energy undernutrition. Other indications may include bowel preparation for surgery in seriously ill or undernourished patients, closure of enterocutaneous fistulas, and small-bowel adaptation after massive intestinal resection or in disorders that may cause malabsorption eg, Crohn disease. If a nasal injury or deformity makes nasal placement difficult, an orogastric or other oroenteric tube can be placed.