What are the routes for parenteral nutrition?

• Side effects
• Preparation
• Administration
• Risks
• Outlook

• Crohn’s disease
• cancer
• short bowel syndrome
• ischemic bowel disease

It also can help people with conditions that result from low blood flow to their bowels.

Parenteral nutrition delivers nutrients such as sugar, carbohydrates, proteins, lipids, electrolytes, and trace elements to the body. These nutrients are vital in maintaining high energy, hydration, and strength levels. Some people only need to get certain types of nutrients intravenously.

The most common side effects of parenteral nutrition are mouth sores, poor night vision, and skin changes. You should speak with your doctor if these conditions don’t go away.

Other less common side effects include:

• changes in heartbeat
• confusion
• convulsions or seizures
• difficulty breathing
• fast weight gain or weight loss
• fatigue
• fever or chills
• increased urination
• jumpy reflexes
• memory loss
• muscle twitching, weakness, or cramps
• stomach pain
• swelling of your hands, feet, or legs
• thirst
• tingling in your hands or feet
• vomiting

Contact your doctor immediately if you experience any of these reactions.

You need to speak with your healthcare provider about your exact nutritional needs. Your provider will prescribe the appropriate liquid for fulfilling these needs. You store this liquid in a refrigerator or freezer.

Each dose must be removed from the fridge four to six hours before use. This allows enough time for the liquid to reach room temperature. Frozen packets should be moved to the refrigerator 24 hours before use to thaw.

Parenteral nutrition is administered from a bag containing the nutrients you need through tubing attached to a needle or catheter.

With TPN, your healthcare provider places the catheter in a large vein, called the superior vena cava, that goes to your heart. Your healthcare provider may also place a port, such as a needleless access port, which makes intravenous feeding easier.

For temporary nutritional needs, your doctor may suggest PPN. This type of intravenous feeding uses a regular peripheral intravenous line instead of a central line threaded into your superior vena cava.

You’ll most likely complete intravenous feedings yourself at home. It usually takes 10 to 12 hours, and you’ll repeat this procedure five to seven times a week.

Your healthcare provider will provide detailed instructions for this procedure. In general, you first need to check your nutrient bags for floating particles and discoloration. Then you insert tubing into the bag and attach the tubing to your intravenous catheter or port as designated by your healthcare provider.

You need to leave the bag and tubing in place for most or all of the day. Afterward, you remove the nutrient bag and tubing.

The most common risk of using parenteral nutrition is developing catheter infection. Other risks include:

• blood clots
• liver disease
• bone disease

It’s essential to maintain clean tubing, needleless access ports, catheters, and other equipment to minimize these risks.

Many people experience some improvement in their condition after parenteral nutrition. You may not be rid of your symptoms, but your body may be able to heal more quickly. You’ll likely feel stronger and more energized. This can help you do more in spite of the effects of your condition.

A physician or dietitian will reassess your nutritional needs after several weeks of this nutrition program to see if any adjustments need to be made in the dosage. You’ll likely have tests done to assess your individual needs.

The results of parenteral nutrition are maintained health and energy levels in your body. You may need this treatment only temporarily. Or you may need to use it for the rest of your life. Your nutritional needs may change with time.

Last medically reviewed on December 16, 2016

Details Last Updated: 20 June 2016

Secure venous access is required for the successful and safe delivery of Parenteral nutrition (PN).

In considering the type of venous access required it is important to consider:

• The time PN support is likely to be required for
• The nutritional requirements of the patient

Central venous access is required for PN support given over longer periods (>28 days). It is recommended that peripheral PN is only used for a short period of time and only when using nutrient solutions where osmolarity does not exceed 850mosm/l, with a substantial proportion of the non protein calories given as lipid. Peripheral PN demands careful surveillance for thrombophlebitis as parenteral feed is very irritant to veins. Central venous catheters have been extensively used for parenteral nutrition. In many hospitals a dedicated single lumen catheter is inserted for parenteral nutrition use only. These may have a Dacron cuff to retain the catheter in place and cuffed catheters are suitable for use for longer term parenteral nutrition at home. It is probably easier to maintain good catheter care and so low infection rates using single lumen dedicated catheters but in critically ill patients with complex fluid and drug requirements, multi-lumen catheters are used. It is unwise to use a multi-lumen catheter which has been in place for some days and used for other purposes to start parenteral nutrition.

Line insertion technique

All lines placed for PN should be done so using aseptic non touch technique. There is compelling evidence that ultrasound guided venepuncture using real time ultrasonography is associated with a lower risk of complication and higher rate of successful placement than 'blind' venepuncture.

Line complications

Complications associated with vascular access for PN can be broadly divided into:

• Insertion related
• Line related 
• Patient related

Insertion related complications include:

• Bleeding (arterial or venous)
• Misplaced lines (suboptimal tip location*)
• Pneumothorax
• Early infection

* Central venous catheter tip should be sited in the lower third of SVC or upper third of right atrium (at or below the level of the carina on plain chest X-ray imaging). There is evidence of increased risk of malfunction including line associated thrombosis associated with tip position > 4cm from cavoatrial junction.

Line related complications include:

• Line fracture and line occlusion

Line fracture can occasionally occur. It is sometimes possible to repair this without the need for line replacement. Factors that influence the risk of line occlusion include the catheter size and use of positive pressure connectors and fluid locks. Infections are more common when cvcs with more lumens than absolutely necessary are used. 

Patient related complications: 

The greatest risk is of infection. This may be bloodstream, tunnel site or exit site infection. In many cases the line can be salvaged with appropriate antibiotic treatment but certain infections necessitate line removal, in particular fungal line infection.

Enteral nutrition (EN) and total parenteral nutrition (TPN) may provide life-sustaining therapy for surgical patients. The duration of nutritional therapy (enteral or parenteral) implies distinct access routes. We review the main aspects related to access routes for nutrient delivery. The enteral route, whenever feasible, is preferred. For EN lasting less than 6 weeks, nasoenteric tubes are the route of choice. Conversely, enterostomy tubes should be used for longer-term enteral feeding and can be placed surgically or with fluoroscopic and endoscopic assistance. The first choice for patients who will not be submitted to laparotomy is percutaneous endoscopic gastrostomy. Postpyloric access, although not consensual, must be considered when there is a high risk of aspiration. For intravenous delivery of nutrients lasting less than 10 days, the peripheral route can be used. However, because of frequent infusion phlebitis, its role is still in discussion. Central venous catheters (CVCs) for TPN delivery may be (1) nonimplantable, percutaneous, nontunneled-used for a few days to 3 to 4 weeks; (2) partially implantable, percutaneous, tunneled-used for longer periods and permanent access; or (3) totally implantable subcutaneous ports-also used for long-term or permanent access. The subclavian vein is usually the insertion site of choice for central venous catheters. Implantable ports are associated with lower rates of septic complications than percutaneous CVCs. The catheter with the least number of necessary lumens should be applied. Central venous nutrient delivery can also be accomplished through peripherally inserted central catheters, which avoid insertion-related risks.