Enteral Feeding: How It Works and When It’s Used
Indications
Types
Procedure
Vs. parenteral feeding
Complications
Contraindications
Outlook
What is enteral feeding?
Enteral feeding refers to intake of food via the gastrointestinal (GI) tract. The GI tract is composed of the mouth, esophagus, stomach, and intestines.

Enteral feeding may mean nutrition taken through the mouth or through a tube that goes directly to the stomach or small intestine. In the medical setting, the term enteral feeding is most often used to mean tube feeding.

A person on enteral feeds usually has a condition or injury that prevents eating a regular diet by mouth, but their GI tract is still able to function.

Being fed through a tube allows them to receive nutrition and keep their GI tract working. Enteral feeding may make up their entire caloric intake or may be used as a supplement.
When is enteral feeding used?
Tube feedings may become necessary when you can’t eat enough calories to meet your nutritional needs. This may occur if you physically can’t eat, can’t eat safely, or if your caloric requirements are increased beyond your ability to eat.

If you can’t eat enough, you’re at risk for malnourishment, weight loss, and very serious health issues. This may happen for a variety of reasons. Some of the more common underlying reasons for enteral feeding include:

a stroke, which may impair ability to swallow
cancer, which may cause fatigue, nausea, and vomiting that make it difficult to eat
critical illness or injury, which reduces energy or ability to eat
failure to thrive or inability to eat in young children or infants
serious illness, which places the body in a state of stress, making it difficult to take in enough nutrients
neurological or movement disorders that increase caloric requirements while making it more difficult to eat
GI dysfunction or disease, although this may require intravenous (IV) nutrition instead

Types of enteral feeding
According to the American College of Gastroenterology, there are six main types of feeding tubes. These tubes may have further subtypes depending on exactly where they end in the stomach or intestines.

The placement of the tube will be chosen by a doctor based on what size tube is needed, how long enteral feeds will be required, and your digestive abilities.

A medical professional will also choose an enteral formula to be used based on tube placement, digestive abilities, and nutritional needs.

The main types of enteral feeding tubes include:

Nasogastric tube (NGT) starts in the nose and ends in the stomach.
Orogastric tube (OGT) starts in the mouth and ends in the stomach.
Nasoenteric tube starts in the nose and ends in the intestines (subtypes include nasojejunal and nasoduodenal tubes).
Oroenteric tube starts in the mouth and ends in the intestines.
Gastrostomy tube is placed through the skin of the abdomen straight to the stomach (subtypes include PEG, PRG, and button tubes).
Jejunostomy tube is placed through the skin of the abdomen straight into the intestines (subtypes include PEJ and PRJ tubes).

Procedure for placing the tube
NGT or OGT
Placement of a nasogastric tube or orogastric tube, while uncomfortable, is fairly straightforward and painless. Anesthesia isn’t required.

Typically a nurse will measure the length of the tube, lubricate the tip, place the tube in your nose or mouth and advance until the tube is in the stomach. The tube is usually secured to your skin using soft tape.

The nurse or doctor will then pull some gastric juice out of the tube using a syringe. They’ll check the pH (acidity) of the liquid to confirm that the tube is in the stomach.

In some cases, a chest X-ray may be needed to confirm placement. Once placement is confirmed, the tube may be used immediately.

Nasoenteric or oroenteric
Tubes that end in the intestines often require endoscopic placement. This means using a thin tube called an endoscope, which has a tiny camera on the end, to place the feeding tube.

The person placing the tube will be able to see where they’re putting it via the camera on the endoscope. The endoscope is then removed, and placement of the feeding tube may be confirmed with aspiration of gastric contents and X-ray.

It’s common practice to wait 4 to 12 hours before using the new feeding tube. Some people will be awake during this procedure, while others may require conscious sedation. There’s no recovery from the tube placement itself, but it may take an hour or two for the sedation medications to wear off.

Gastrostomy or jejunostomy
Placement of gastrostomy or jejunostomy tubes is also a procedure that may require conscious sedation, or occasionally general anesthesia.

An endoscope is used to visualize where the tube needs to go, and then a tiny cut is made in the abdomen to feed the tube into the stomach or intestines. The tube is then secured to the skin.

Many endoscopists choose to wait 12 hours before using the new feeding tube. Recovery may take five to seven days. Some people experience discomfort at the tube insertion site, but the incision is so small that it typically heals very well. You may receive antibiotics to prevent infection.

Enteral vs. parenteral feeding
In some cases, enteral feeding may not be an option. If you’re at risk for malnutrition and don’t have a functional GI system, you may need an option called parenteral feeding.

Parenteral feeding refers to giving nutrition through a person’s veins. You’ll have a type of venous access device, such as a port or a peripherally inserted central catheter (PICC or PIC line), inserted so you can receive liquid nutrition.

If this is your supplementary nutrition, it’s called peripheral parenteral nutrition (PPN). When you’re getting all of your nutritional requirements through an IV, it’s often called total parenteral nutrition (TPN).

Parenteral feeding can be a life-saving option in many circumstances. However, it’s preferable to use enteral nutrition if at all possible. Enteral nutrition most closely mimics regular eating and can help with immune system function.

Possible complications of enteral feeding
There are some complications that can occur as a result of enteral feeding. Some of the most common include:

aspiration, which is food going into the lungs
refeeding syndrome, dangerous electrolyte imbalances that may occur in people who are very malnourished and start receiving enteral feeds
infection of the tube or insertion site
nausea and vomiting that may result from feeds that are too large or fast, or from slowed emptying of the stomach
skin irritation at the tube insertion site
diarrhea due to a liquid diet or possibly medications
tube dislodgement
tube blockage, which may occur if not flushed properly
There are not typically long-term complications of enteral feeding.

When you resume normal eating, you may have some digestive discomfort as your body readjusts to solid foods.

Who shouldn’t have enteral feeding?
The main reason a person wouldn’t be able to have enteral feeds is if their stomach or intestines aren’t working properly.

Someone with a bowel obstruction, decreased blood flow to their intestines (ischemic bowel), or severe intestinal disease such as Crohn’s disease would likely not benefit from enteral feedings.
The outlook
Enteral feeding is often used as a short-term solution while someone recovers from an illness, injury, or surgery. Most people receiving enteral feeds return to regular eating.

There are some situations where enteral feeding is used as a long-term solution, such as for people with movement disorders or children with physical disabilities.

In some cases, enteral nutrition can be used to prolong life in someone who is critically ill or an older person who can’t maintain their nutritional needs. The ethics of using enteral feeding to prolong life have to be evaluated in each individual case.

Enteral feeding can seem like a challenging adjustment for you or a loved one. Your doctor, nurses, a nutritionist, and home health care providers can help make this adjustment a successful one.