Danielle has a PhD in Natural Resource Sciences and a MSc in Biological Sciences
Wow - it's pretty intimidating to start a lesson with nothing but acronyms to go off of, but this will be painless and you'll walk away with a good understanding of TPN and PPN. First of all, TPN stands for total parenteral nutrition, and PPN stands for peripheral parenteral nutrition. So right off the bat you can see we're going to be discussing two types of parenteral nutrition. That's a good start.
So what is parenteral nutrition? Parenteral nutrition is used to treat patients who cannot eat or have limited digestive powers by providing a liquid mixture of nutrients directly to the bloodstream. Parenteral nutrition is delivered intravenously to a vein and includes protein, carbohydrates, fats, vitamins, minerals, and any other nutrients required by the body.
Parenteral nutrition is different than enteral nutrition, which is the use of a feeding tube to provide nutrients directly to the stomach for digestion. Parenteral nutrition may be used if a feeding tube didn't work or if the patient suffers from conditions like Crohn's disease, cancer, short bowel syndrome, or ischemic bowel disease to list a few.
Now that we have that out of the way, let's look at the two types of parenteral nutrition: total parenteral nutrition and peripheral parenteral nutrition.
Total Parenteral Nutrition (TPN)
Total parenteral nutrition, or TPN, is used when this is the only source of nutrition the patient is receiving. They're entirely dependent on TPN for all of their nutrition. It is primarily used to treat patients with digestive system disorders or patients who are recovering from a serious accident or surgery.
TPN delivers a liquid mix of nutrients at a very high concentration and is high in calories, so less volume is needed (when compared to PPN). For example, carbohydrates are more than 10% of the solution. Because of this higher concentration of nutrients, TPN has to be delivered through a large vein, usually found in the neck or chest. Because it's delivered through a major vein, TPN is typically used for long-term treatment cases, though patients are at a higher risk of infection.
Peripheral Parenteral Nutrition (PPN)
Now that we have an understanding of TPN, let's look at peripheral parenteral nutrition (or PPN). PPN is used when the patient has another source of nutrition; it's meant to act as a supplement rather than the patient's only nutrient source. As a result, PPN is less concentrated and lower in calories than TPN and can be administered through smaller, peripheral veins (hence, the name PPN). However, because it uses smaller veins, PPN is not meant to be used long-term because it can damage these more vulnerable veins.
PPN is most often used to treat patients who need short-term nutrition supplementation, perhaps due to blocked digestion or to get a nutritional 'boost' during a long-term hospital stay. Compared to TPN, PPN is low in carbohydrates (less than 10%) and offers a lower concentration of nutrients. As a result, more volume is needed to reach the same nutritional value as TPN. PPN offers a lower risk of infection than TPN, though both forms are still more expensive than enteral nutrition options.
Parenteral nutrition is used when a patient needs a liquid mixture of nutrients delivered intravenously, directly into a vein. This is unlike enteral nutrition, which is the use of a feeding tube to provide nutrients directly to the stomach for digestion. There are a number of conditions that may require parenteral nutrition, and there are two types of it that we covered:
- Total parenteral nutrition (TPN) is the only source of nutrition the patient is receiving. Administered through a large vein, the solution has a high nutrient and calorie content (carbohydrates make up more than 10%). Despite a high risk of infection, TPN is meant for long-term use.
- Peripheral parenteral nutrition (PPN) is meant to act as a supplement and is used when the patient has another source of nutrition. Administered in smaller veins, the solution is lower in nutrient and calorie content than TPN. PPN, therefore, has a lower risk of infection, though is typically for short-term use due to the vulnerability of the small veins.
They vary in their nutrient composition, caloric content, administration methods, and overall uses, but they act to ensure a patient gets the best nutrition needed for a successful recovery.
Medical Disclaimer: The information on this site is for your information only and is not a substitute for professional medical advice.
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