Pathophysiology
Clinical meaning
Enteral nutrition delivers nutrients directly into the gastrointestinal tract via tubes when patients cannot meet nutritional needs orally but have a functional GI tract. Nasogastric (NG) tubes are used for short-term feeding (< 4 weeks), while percutaneous endoscopic gastrostomy (PEG) tubes provide long-term access. Jejunal feeding tubes bypass the stomach and are indicated for patients with gastroparesis, high aspiration risk, or pancreatitis. Continuous feeding delivers formula at a constant rate via pump, reducing dumping syndrome risk. Bolus feeding mimics normal meal patterns but carries higher aspiration risk. The gut-associated lymphoid tissue (GALT) requires enteral stimulation to maintain immune function and mucosal barrier integrity, making enteral feeding preferable to parenteral nutrition when the GI tract is functional.