What Is Parenteral Nutrition?

Intravenous feeding may be necessary for some patients

Some patients may require intravenous feeding.
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People who don't have a functioning digestive system need to get nutrition delivered into the blood stream. The nutrients need to be in a form that can be used by the body.

Parenteral nutrition is a way to feed people who can't eat or digest foods normally. It bypasses the digestive system completely because the nutrients are put right into the bloodstream. It may be used to avoid or treat malnutrition for a few days or even longer if necessary.

An intravenous catheter is placed in a vein, and a nutrient solution containing carbohydrates, protein, fats, vitamins and minerals is fed through the catheter. It can take many hours to complete the process and is usually done once a day.

Parental nutrition is different from enteral nutrition, which is tube feeding. Enteral nutrition requires at least some digestive system function, and are generally preferred over parenteral nutrition, but people who can't have enteral feedings will need parenteral nutrition.

Peripheral Parenteral Nutrition

This type of parenteral nutrition involves placing a catheter into a vein in the arm, and it's typically used for short term feedings, usually no more than seven days.

The formulas used with peripheral parenteral nutrition don't have enough calories to use long term because that would make the solution too thick to get into the smaller veins of the arm.

 Peripheral parental nutrition is done at medical facilities.

Central Parenteral Nutrition

This form of parenteral nutrition involves placing the catheter in a vein in the chest. It allows delivery of nutrient solutions that are more concentrated, so it's often used for people need parenteral nutrition, but also need to have their fluid intake restricted.

It's also better for long-term use because it allows solutions that have a sufficient number of calories.

The placement of the catheter needs to be done at a medical facility. After that, central parenteral nutrition can be done at the facility or home.

Who Needs Parenteral Nutrition?

Digestive system damage can be due to injury to any parts of the digestive system, certain illnesses like severe inflammatory bowel disease, or due to medical procedures such as intensive chemotherapy. 

People who are undergoing parenteral nutrition need close monitoring to make sure they're getting enough of the nutrients and the right amount of fluid. This can involve laboratory testing as well as physical examination. Patients also need to be watched for any possible complications.

Potential Complications

Parenteral nutrition can have some problems, usually from the solutions used or from the catheter. Fluid imbalances can occur, which might lead to dehydration and shock. If the kidneys or heart aren't functioning correctly, this can also lead to heart failure.

Infections at the site of the catheter can also happen if proper care isn't taken to keep the area cleaned and dressed properly.


American Society for Parenteral and Enteral Nutrition. "What is Parenteral Nutrition." Accessed April 14, 2016. http://www.nutritioncare.org/wcontent.aspx?id=270.

Healthline. "Parenteral Nutrition." Accessed April 14, 2016. http://www.healthline.com/galecontent/parenteral-nutrition .

MedlinePlus. "Total Parenteral Nutrition." Accessed Apriul 14, 2016. http://www.nlm.nih.gov/medlineplus/druginfo/meds/a601166.html.

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