Types of nutritional support

There are two main types of feeding system:

  • Enteral nutrition (EN)
  • Parenteral nutrition (PN)

Enteral nutrition (EN) is when nutritional fluid is given through a tube going into the stomach or small intestine. It may be given when the digestive system is working well, but you have problems eating enough.

If you only need nutritional support for a short time, the tube may be passed through the nose down into the stomach. If nutritional support is likely to be needed for more than a few weeks, a tube is passed through the skin and muscle of your abdomen straight into the stomach or small bowel.

Parenteral nutrition (PN) is giving nutrients and fluid directly into the bloodstream through a tube going into a vein in the neck, chest or arm. It is sometimes called total parenteral nutrition. It is usually only used for short periods of time.

There are some other types of feeding options. Your doctor will decide which feeding system is best for you based on your individual circumstances.

Types of nutritional support

Two main types of feeding system are used, known as enteral nutrition (EN) and parenteral nutrition (PN). The type of nutritional support you have depends on a number of factors.

Enteral nutrition (EN)

This is where the nutritional fluid is given into the gut through a tube going into the stomach, or small intestine. There are different ways of giving EN.

EN is best for you if your digestive system is working normally, but you aren't able to eat enough - for example, because of a cancer in the head or neck area.

Parenteral nutrition (PN)

This is where the nutritional fluid is given through a tube that is put into a vein (intravenously). PN aims to provide nutritional support when it isn’t possible to take nutrients through your digestive system.

PN is usually used if people are unable to have EN. This may be due to major surgery on the small bowel, a bowel obstruction or a difficulty with inserting the tubes used for EN. Difficulty with inserting EN tubes may happen after some types of surgery to the head, neck or stomach.

We have a section on diet after stomach surgery, which you may find helpful.

Enteral nutrition (EN)

There are several ways of giving EN. The most common methods used are:

  • nasogastric (NG) feeding - a thin tube is passed down the nose and into the stomach
  • percutaneous endoscopic gastrostomy (PEG) and radiologically inserted gastrostomy (RIG) feeding - a tube is passed through the skin and muscle of the abdomen into the stomach
  • percutaneous endoscopic jejunostomy (PEJ) feeding - a tube is passed through the skin and muscle of the abdomen into the middle of the small bowel (the jejunum) just below the stomach.

Nutritional support through a NG or PEG and RIG feeding is often used after surgery to the head, neck, stomach or gullet (oesophagus).

Nasogastric (NG) feeding

Nasogastric feeding is usually recommended if you’re likely to need nutritional support for only a short time. NG feeding may also be used for people having radiotherapy to the mouth, throat or gullet, if swallowing becomes difficult because of swelling from the treatment.

How an NG tube is put in

You will need to be in a comfortable position, sitting upright. A thin, flexible tube is gently inserted into your nostril, down the back of the throat, down the gullet (oesophagus) and into your stomach. It's important that the person inserting the NG tube checks it is correctly positioned in your stomach.

This is done by drawing some fluid out from the tube using a syringe. As stomach fluid is very acidic, fluid drawn out from the tube is tested for acidity with a pH indicator to show whether or not the tube is in the stomach. Sometimes an x-ray may be necessary to make sure that the tube is correctly placed in the stomach.

Once the tube is correctly positioned, it will be taped to your nose or cheek to keep it in place.

Your dietitian will work out how much liquid food you need to have each day. The hospital staff will give you this through the tube. If you’re at home, the liquid food can be prescribed by your GP, who will ask your local pharmacy to supply it for you. You or your carer will be shown how to give the liquid food. A district nurse will also visit you.

Other fluids, such as liquid medicines, can be given through the tube. Medicines can block the tube if they aren't diluted properly and flushed through with plenty of liquid. Your dietitian, doctor, nurses or pharmacist can advise you about which medicines can be given through the tube. They can also show you how to give them properly.

Nasogastric tube
Nasogastric tube

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Possible problems with NG feeding

There can be disadvantages and possible complications with any type of nutritional support. With NG feeding these are:

  • You may find the insertion of an NG tube uncomfortable and possibly quite distressing. The procedure is usually completed very quickly, although sometimes it can take more than one attempt to get the tube into the right place.
  • As the end of the tube comes out through the nostril and is taped to the face, it is obviously visible. You may find this embarrassing and feel self-conscious about it.
  • NG tubes can be pulled out of the stomach if they aren't fixed securely. Before each feed, the position of the tube needs to be checked. In hospital the nurses will do this or will show you how to do it. Normally, some fluid is drawn out of the tube and checked with a pH indicator. If you’re at home, you, or your carer(s), will need to do this before each feed. Sometimes the tube may fall out completely and will then need to be replaced.
  • Occasionally the tube may become dislodged. This can result in the tip of the tube entering the lungs. If checking the position of the tube indicates that it has become dislodged, it should be removed and replaced.
  • NG tubes can sometimes become blocked. Water is flushed down the tube at regular intervals to try to prevent this from happening. However, if a blockage occurs and can't be cleared, the tube will need to be removed and a new one put in.
  • An NG feed can be inconvenient, as the liquid food often needs to be given slowly into the tube over a number of hours. You won't be able to move around freely during this time. Some people prefer to have their feed given overnight so that they aren't restricted during the day. Your dietitian will talk to you about the best way of giving the feed, so that it doesn't interfere too much with your lifestyle. It may be possible to use a small portable pump to regulate the flow of the feed.
  • If the feed is given too quickly it can flow up into the gullet, which can be very unpleasant and may make you feel sick. Medicines can be given to control this, so let your doctor know if this occurs.

Percutaneous endoscopic gastrostomy (PEG) and radiologically inserted gastrostomy (RIG) feeding

Gastrostomy feeding is recommended if your digestive system is still working well but nutritional support is likely to be needed for more than a few weeks.

Gastrostomy feeding involves surgically creating an opening, known as a fistula, through the abdominal wall. A feeding tube is then passed through the opening and into the stomach.

The feeding tube is held in place with either a stitch, a small inflated balloon around the tube just under the skin, or a flange around the tube just under the skin.

How a PEG is put in

Before a PEG is put in, a doctor or specialist nurse will explain the procedure to you. You will be asked to sign a form saying that you agree (consent ) to having the PEG put in, and that you understand why it is being done.

You’ll need to have nothing to eat or drink for several hours before the procedure to make sure that your stomach is empty. Your doctor will also give you antibiotics to reduce your risk of getting an infection.

You'll be given a sedative to make you feel sleepy. A flexible tube with a light at the end (an endoscope) is passed into your mouth, down your gullet and then into the stomach. The stomach is inflated with air, and the endoscope is positioned so that the light at the end shines through the abdominal wall to show the position of the stomach.

The skin of the abdominal wall is then cleaned and a local anaesthetic is used to numb the area. A small cut is made through the skin and muscle through which a feeding tube is inserted into the stomach.

Once the tube is in place, the area around the tube (the tube site) is cleaned. A dressing isn't usually necessary unless there is leakage of fluid from the site. The area around the tube needs to be cleaned daily with soap and water and thoroughly dried. The tube needs to be flushed with 30ml of water before and after each feed.

It takes approximately three weeks for the skin to heal around the tube. During this time, you should avoid getting the area wet. It's fine to shower as long as the exit site is protected. It's also fine to wash, but you should avoid having a bath.

Your dietitian will discuss with you how much liquid food you need to have through the tube each day.

How a RIG is put in

A RIG is inserted in a similar way to a PEG, but x-ray scanning equipment is used to position it. An NG tube is inserted (as above). You will then have some local anaesthetic injected to numb an area on your abdomen before a small cut (incision) is made.

Some air is pumped down the NG tube and into the stomach that helps position the RIG tube accurately. The gastrostomy tube is then put directly into the stomach using x-ray guidance.

Once the gastrostomy tube is in place, some dye is flushed into it and an x-ray is taken to make sure it's in the right place. After this the NG tube can be removed. The RIG is held in place with stitches, which are removed about 10 days later.

Percutaneous endoscopic gas
Percutaneous endoscopic gas

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Benefit of PEG/RIG feeding

PEGs and RIGs allow people who can't eat in the usual way to take in enough liquid food and fluids. These tubes can't be seen when people are wearing clothes, but a nasogastric (NG) tube can be.

Possible problems with PEG/RIG feeding

The most common complications with a PEG or RIG tube include:

  • a blockage developing in the tube – flushing the tube before and after each feed reduces the chance of this happening
  • infection developing in the tissues around the site.

It is important to tell your doctor as soon as possible if:

  • the skin around the tube becomes red or swollen
  • you notice discoloured fluid coming from around the tube
  • you develop a high temperature or feel unwell.

If the feed is given too quickly, some people may feel nausea or have a sensation of stomach contents flowing back up the gullet (reflux). Let your doctor know if this happens, as they can give you medicines to help.

As with NG feeding, the feed needs to be given slowly and this can restrict you from being able to move around freely. For this reason, many people prefer to have their feed overnight. Your dietitian can discuss your feeding with you, so that you can minimise the disruption to your daily life.

If you’re at home, you should be given the name of a healthcare professional at the hospital so that you can contact them if you develop any problem with your PEG/RIG tube.

PEG/RIG tubes can stay in place for up to two years, but many people have them for much shorter periods. After this, they can be replaced if they are still needed.

Percutaneous endoscopic jejunostomy (PEJ) feeding

Some people may have a percutaneous endoscopic jejunostomy (PEJ), also called a jejunostomy tube. This procedure is similar to a PEG/RIG, but the tube is passed into the middle part of the small bowel (the jejunum) instead of the stomach. A jejunostomy tube may be inserted at the same time as surgery to the gullet or stomach.

The possible problems and care needs are the same as for PEG/RIG tubes. But a PEJ tube needs to be given more slowly, and the water put into the PEJ needs to be sterile, or boiled then cooled.

Parenteral nutrition (PN)(or total parenteral nutrition)

Parenteral nutrition (PN) means giving nutrients and fluid directly into the bloodstream. PN is sometimes referred to as TPN, which means total parenteral nutrition. However, as it is not always possible to provide total nutrition through the bloodstream, TPN is more commonly known as PN.

How PN is given

PN is usually given through a thin tube, which is inserted into a large vein in your neck or chest. The tube is known as a central line. Sometimes it is given through a thin tube in your arm that goes up into a vein in your chest. This is called a PICC line (peripherally inserted central catheter).

Occasionally, a vein in the arm may be used (like having an ordinary drip), but this is less common. It tends to be used if feeding is only necessary for a short period of time (fewer than 10 days) and if you’re not on restricted fluids, as fluids need to be more diluted if an arm vein is used.

The doctors will take into account your individual circumstances and decide the best type of feeding for you.

How the central or PICC line is put in

Your central or PICC line will be put in at the hospital by a specially trained nurse or doctor. A central line is usually put in under a general anaesthetic, but sometimes a local anaesthetic may be used. A PICC line is put in using a local anaesthetic.

You will have an x-ray to make sure that the tube is in the right place.You shouldn't feel any pain when the tube is being put in, but you may feel a bit sore for a few days afterwards. A mild painkiller such as paracetamol will help ease this.

Benefits of PN

PN allows nutrition to be given even when the digestive tract isn't working. It can allow the digestive tract to rest so that it can heal – for example, after surgery to the stomach or bowel. It can also be used if you are experiencing severe vomiting or diarrhoea and cannot have enteral feeding.

Possible problems with PN

It's possible for an infection to develop either inside the line or around the exit site. You should tell your doctor if:

  • the exit site becomes red or swollen
  • you notice discoloured fluid coming from it
  • you develop a temperature.

You may be given antibiotics or, if the infection is serious, the tube may have to be removed.

It is possible for a blood clot (thrombosis) to form in your vein at the tip of the central line. If this happens, the tube may have to be removed. You may be given some anti-clotting medicines to prevent this from happening. The medicines are usually added to the feed.

You will have regular blood tests while having PN. This is to check that your levels of sugar, minerals and other substances are normal. PN can sometimes alter your blood sugar levels and you may need insulin to control your sugars if they are too high. Your feed will be specially prepared for you each day according to your blood levels and nutritional needs.

PN is usually started gradually. Your feed will be reduced over a few days when you no longer need it.

Home feeding

Many people can have their nutritional support at home. Having parenteral nutrition is more difficult to deal with than NG or PEG feeding. You may need to be referred to a specialist hospital to be shown how to manage the parenteral feeds at home.

The thought of having nutritional support at home may make you feel anxious. Before you’re discharged from hospital, you will be given training in how to manage your particular feeding system. If you have a carer, or carers, they will be given training too.

Home nutritional support will not start until you, and your carer(s) if you have one, feel confident in dealing with the tube and the feeds.

A team of healthcare professionals will also help to support you at home. The support offered to people may vary, but your GP, district nurse and dietitian can help you.

Some NHS trusts work in partnership with specialist home-care companies to ensure that people who go from hospital care to home care receive the support and expertise they need.

Your feelings

Many people feel upset if they need nutritional support or cannot eat or drink as they normally would. You may find having enteral feeding such as an NG tube or a PEG affects how you feel about your body image. These are all normal reactions. It is part of the process many people go through in trying to come to terms with their condition.

Everyone has their own way of coping with difficult situations. It may be helpful to talk to your doctor, specialist nurse or dietitian about how you feel. Some people find it helpful to talk to family or friends, while others prefer to seek help from people outside their situation. Others may prefer to keep their feelings to themselves. There is no right or wrong way of coping, but help is available if you need it. You may wish to contact our cancer support specialists for information about counselling in your area.

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