What Is Parenteral Nutrition?

It can be scary to hear that you might need to be fed intravenously. Let’s break down what parenteral nutrition is and why you may need it.

Parenteral nutrition is used when a person’s digestive system does not function either completely or partially. This means that a person who needs parenteral nutrition may be unable to swallow food, move food through the digestive system, or intake nutrients from food.¹

During normal digestion, food is broken down in the stomach and bowel and absorbed by the bowel after which nutrients are carried by the blood to different parts of the body. But during parenteral nutrition, this process is bypassed and a liquid mixture containing nutrients is given directly into the blood through an intravenous (IV) catheter. This liquid mixture contains carbohydrates, proteins, fats, as well as vitamins and minerals.² This mode of feeding where food is given intravenously can be used in addition to food taken by mouth and address part of a person’s nutritional requirements (partial parenteral nutrition), or it may be used to address a person’s nutritional needs completely (total parenteral nutrition).

If your digestive system works to some extent you may not need parenteral nutrition instead your doctor may recommend enteral feeding for you. Unlike parenteral nutrition where nutrients are absorbed directly into the bloodstream, during enteral nutrition nutrients are fed into a part of the digestive system, for instance, a jejunostomy tube that feeds into the small intestine or a gastrostomy tube in that feeds into the stomach.

Who Needs Parenteral Nutrition?

People with a variety of diseases that damage their ability to intake food, or digest or absorb nutrients may need parenteral nutrition. For instance, people with short bowel syndrome (where a part of the small intestine has been removed through surgery or is missing and nutrients can’t be properly absorbed),³ GI fistulas (where an abnormal opening in the intestines or stomach causes the contents to leak out), ⁴ bowel obstruction (where the bowel is completely or partially blocked so that the contents of the intestine can’t pass through),⁵ or severe acute pancreatitis ( where you see inflammation and swelling of the pancreas which produces enzymes needed to digest food).

Also, while some patients may only require this mode of nutrition for a short while, some patients receive it throughout their lives.⁶

How Is Parenteral Nutrition Administered?

Parenteral nutrition is administered through a large intravenous tube. This tube (known as a central venous catheter) is inserted into a large vein, say in the chest or arm and nutrition is given through it. Your doctor will help choose the appropriate catheter from the many different kinds ( like PICC, Hickman, triple lumen, single lumen, double lumen catheters etc) that are available. But you don’t necessarily have to stay in a hospital to receive parenteral nutrition, it can be administered at home too.⁷

How Will Being On Parenteral Nutrition Affect Your Life?

Parenteral nutrition doesn’t cause pain but it will probably cause some inconvenience and you can expect some lifestyle changes if you’re on it. But you can minimize this, for instance, doing the nutritional infusion at night will help you keep to a normal routine and your daily activities won’t be disrupted. However, do keep in mind that while it’s important to maintain a sense of normalcy some activities like contact sports and swimming are best avoided. Do speak to your doctor about the precautions that you might need to take while you’re on parenteral nutrition.⁸

Complications Due To Parenteral Nutrition

Various issues could arise when you go in for intravenous feeding:

• You might get injured while the catheter is inserted and a nerve or blood vessel could get damaged.
• Blood clots can sometimes form in the vein that the catheter is placed in.
• Infections are more likely when the skin is broken (like when an incision is made to insert a catheter) since it’s the skin that usually prevents germs from entering the body. Infections are especially likely if a catheter is left in for a long time. Being careful about hygiene and using sterile techniques can help prevent this.
• Nutritional deficiencies and imbalances may come about during intravenous feeding. Your blood sugar levels may go too low (hypoglycemia) or too high (hyperglycemia). You might also become deficient in certain minerals and vitamins. Doctors regularly test the blood for sugar and minerals and adjust the nutrition formula to prevent this from happening.
• Too little or too much water can also cause problems – too little results in dehydration, too much can cause fluid to accumulate in the lungs and make it difficult for you to breathe. Doctors try to calculate the amount of water require before starting feeding to avoid the risk of water imbalances.
• Sometimes issues can crop up because of feeding formulas that contain more fat and lesser carbohydrates (these are known as lipid emulsions). These might cause nausea, difficulty breathing, headache, allergic reactions, sweating, back pain, and dizziness. You might find that the levels of fat (lipid) in the blood rises temporarily. This can also lead to the enlargement of the spleen or liver and cause people to bruise and bleed more easily as well as develop infections more frequently. To address these problems doctors may slow or even stop the formula.
• If intravenous feeding goes on for more than 3 months your bone density may decrease and advanced cases can experience pain in the legs, joints, and back.
• Liver problems may sometimes develop in people who are on parenteral nutrition. Infants are most commonly affected by this. Reducing the amount of protein or carbohydrate can be helpful in some cases.
• If the gallbladder is inactive as during intravenous feeding then problems could develop. Substances like cholesterol that are usually processed through the gallbladder could build up forming gallstones. These stones can block ducts and cause inflammation. Increasing the amount of fat and stopping sugar for some hours in a day can trigger contractions in the gallbladder and move the substances that have built up. Eating normally through the mouth can also be useful.⁹