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Parenteral nutrition - Information for patients

Patient information A-Z

We hope that you will find this information helpful but do not hesitate to ask your nurses or doctors, particularly members of the Intestinal Rehabilitation team, if you would like to know more.

What is parenteral nutrition (PN)?

Parenteral (or intravenous) nutrition is a different way of providing all the nutrients your body needs whilst you cannot eat. It is introduced directly into the bloodstream, bypassing the digestive system.

How is this done?

You will be taken to the Vascular Unit, where a specialist nurse will insert a line into a vein in your arm. Insertion takes place under strict sterile conditions to reduce the risk of infection. If your line site becomes red, hot or painful, please inform your nurse immediately. The nurse should refer to the guidelines in your medical notes.

Image showing example line insertion into a vein in the arm
Line insertion into a vein in the arm

Will PN provide all my requirements?

Yes. PN will provide all the nutrients needed to maintain good health until you resume normal food intake.

What does the PN contain?

  • Glucose - gives immediate energy.
  • Proteins - are essential for growth, healing and maintenance of body tissues.
  • Fats - maintain energy stores.
  • Vitamins - keep the body healthy and functioning correctly.
  • Minerals - help make blood cells, are important in normal healing and keep muscles in working order.

Will I feel hungry or thirsty?

PN satisfies the appetite, so you should not feel hungry or thirsty. If your mouth feels dry, cleaning your teeth and regular mouthwashes may help.

May I eat and drink at the same time as having the PN?

This depends upon your medical condition. Complete rest of the digestive system may be recommended, or a small amount of water may be allowed. As soon as your digestive system function returns, we and your medical team will discuss restarting fluid by mouth and, later, food.

Will feeding continue during sleep?

Yes. PN is given by continuous infusion. In some cases though, the timing may be altered to provide a degree of freedom from the infusion. Please discuss with the Intestinal Rehabilitation team if this is possible for you.

What about moving around freely?

The equipment will hang on a mobile stand, and the pump’s battery lasts for several hours so should not restrict your movement. You may need help to push the equipment around. Bathing or showering is possible, taking care not to get the line or dressing wet.

What is the effect on my bowels?

Mucus, cells and bacteria may still produce a bowel movement, despite no food intake by mouth. PN goes straight into the blood stream and does not cause diarrhoea or abdominal pain. It should not cause nausea.


Whilst receiving PN we will monitor your progress carefully to ensure that you are being given the right nutrients for your needs, to ensure your body is tolerating the glucose and that you are infection free.

  • Blood samples will be taken regularly to check your electrolyte levels, kidney and liver function.
  • Urine samples will be tested to check for the presence of glucose.
  • Temperature and pulse rate will be recorded regularly to check for the absence of infection.
  • Body weight will be measured, a minimum of once per week.

We may change the feed composition according to your results.

When food is started again, we will keep a record of everything you eat or drink in order to wean you safely off PN.

Once PN is stopped, the feeding line may be removed. This quick, painless procedure will be carried out by a registered nurse on the ward.

Addenbrooke’s Intestinal Rehabilitation team will visit you regularly to monitor your progress.

We are working together with your nurses and doctors to co-ordinate your nutritional care.

Are there any risks associated with PN?

All measures are taken to ensure risks are minimized.

Line infection is possible and will be monitored regularly by taking your temperature.

High blood sugars can occur; this will be monitored by taking urine samples or finger pricks to test blood sugar.

Is there any alternative to PN?

Not if you need to bypass your digestive system and rest your gut.

We aim to re-establish normal eating and drinking using your gut as soon as there are signs that the initial problem is resolving.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151