What Is Enteral and Parenteral Nutrition?

Enteral and parenteral nutrition are two means of delivering nutrition to patients who cannot digest food normally. Enteral feeding delivers liquid nutrition through a catheter inserted directly into the gastrointestinal (GI) tract. Parenteral nutrition provides nutrition intravenously, or directly into the bloodstream. Both types of nutrition are provided in liquid form and can include medicine as well as food. Because it presents less risk, enteral feeding is preferred to intravenous feeding when the option is available.

These types of nutrition are used on patients who have damaged or non-functioning GI tracts. The GI tract is the group of organs through which food travels to be digested and excreted. These organs include the mouth, where food is taken into the body, the pharynx, the esophagus, the stomach, and the intestines, or bowels, which are responsible for the final break-down, absorption, and excretion of food.

Different enteral feeding tubes may be used for different patient’s needs. A nasal tube is run through the patient’s nasal passageway, through the esophagus, into the stomach. This bypasses the mouth and throat, but still uses the stomach. Nasal tubes cannot be used, however, on patients with obstructions in the esophagus or injuries to the mid-face. In these cases, a gastric feeding tube may be surgically placed directly into the stomach, avoiding the nose, mouth, and throat. These procedures are usually performed on patients who have mouth or throat cancer, trauma to the mouth or throat, neurological problems that prevent the patient from swallowing, or patients with a severe eating disorder, such as anorexia nervosa.

When a patient’s stomach is unfit for normal digestion or a catheter, doctors may recommend a jejunostomy tube (J-tube), instead. The J-tube is a feeding tube that is surgically placed in the jejunum, or the middle segment of the small intestine. In the digestive tract, the small intestine is positioned after the stomach and is used to break down and absorb food.

Sometimes, enteral feeding is not an option due to post-surgery paralysis of the GI tract, chronic diarrhea or vomiting, or for starving patients who need surgery. These patients may require total parenteral nutrition (TPN), which delivers nutrition solely through intravenous feeding. Medical professionals typically insert catheters into either the jugular vein; the subclavian vein, below the clavicle; or one of the arm’s large blood vessels. TPN is also recommended for babies with underdeveloped digestive systems, patients with birth defects along the GI tract, patients suffering bowel obstructions, and patients with Crohn’s disease, an inflammation of the bowels.

Many times, a patient can return to normal eating after he regains the strength, but some patients continue to need tube feeding for a long period of time. Both enteral and parenteral nutrition patients can administer food independently from home in certain chronic cases. These patients often choose to do feedings at night, in order to have their lifestyles be as normal as possible during the day. Feeding operations and care will vary from case to case.