Enteral nutrition, also called tube feeding, is a means of providing nutrition and energy for people who are unable to eat enough food because of illness. People who require enteral feeding might have a decreased appetite or have difficulty swallowing because of pain or because of an illness or injury that prevents swallowing. Enteral nutrition provides these people with a carefully balanced food source that contains all of the nutrients they need to stay alive.
In normal feeding and digestion, food is chewed in the mouth and then swallowed. In the stomach and large intestine, the food is broken down into constituent molecules, and in the small intestine and bowel, nutrients are absorbed for distribution throughout the body. An illness or injury that prevents someone from swallowing food can quickly lead to nutrient or energy starvation. Enteral feeding supplies nutrients and energy directly to the stomach, so that the process of chewing and swallowing is bypassed entirely.
This type of nutritional support is in contrast to parenteral nutrition, in which nutrients are provided via an intravenous line inserted into a vein. Parenteral nutrition is given in cases where a patient cannot digest food because part of his or her digestive tract is non-functional. Enteral nutrition is given when someone has a functional digestive tract but cannot swallow food.
Enteral nutrition can be provided in one of several ways. One is a nasogastric feeding tube, a long, thin tube placed in the nose and fed through the nasal passage to the esophagus and into the stomach. Other types of nasal feeding tubes include the nasoduodenal tube and the nasojejunal tube. Each tube feeds into a different location in the small intestine: the nasoduodenal tube feeds into the duodenum, and the nasojejunal tube feeds into the jejunum. The type of nasal feeding tube used depends on what the patient is able to tolerate and whether he or she has any digestive diseases such as esophageal reflux.
Nasal feeding tubes are used preferentially when enteral feeding will be of short duration. If a patient requires long-term enteral nutrition, a gastrostomy tube is more likely to be used. This tube provides direct access to the stomach via a surgically created hole in the abdomen called a stoma. When the tube is placed directly into the stomach, the tube is a gastrostomy; if the tube is placed directly into the jejunum, it is called a jejunostomy. These feeding tubes require extra care to ensure that the stoma does not become infected.