Nasogastric tube feeding overview

A nasogastric (NG) tube is a polyurethane or silicone tube that is inserted into the stomach via the nasal passage. Orogastric tubes may also be used particularly if the nasal passages are compromised or being used to administer oxygen, e.g. CPAP. The two main reasons for using a NG tube are:

1. to supply nutrition;
   
2. to empty the gastrointestinal tract.

Infants and children can be fed via a nasogastric tube either totally or partially. The feeds can be given via gravity or via a pump on an intermittent or on a continuous basis.

Equipment

• Plastic apron and gloves
  
• Clear work surface, i.e. tray
  
• 20–50 ml syringes
  
• Sterile water
  
• pH indicator paper and comparison chart (CE marked paper)
  
• Feed as prescribed
  
• Pump – continuous feed
  
• Giving set – bolus, intermittent feed

Procedure

Before commencing a feed, the position of the tube must be confirmed. This will be done by aspirating the gastric secretions. Parental consent should be obtained and also the consent of the child should be obtained. Ensure the child is in a comfortable position, ideally sitting on their parent’s knee if possible. If in a bed or cot, then tilt the head of the bed/cot to a 45° angle so as to prevent aspiration.

Local policy should be followed:

• Wash hands and put on apron and gloves.
  
• Connect the 20 ml syringe to the port of the NG tube and aspirate 0.5–1 ml of gastric contents.
  
• Drop onto the pH paper and match the colour to the comparison chart. The pH should be below 5.5 for infants (term) and children.

Bolus feed

Remove the giving set and using the aseptic non-touch technique attach the 50 ml syringe to the top of the giving set. Prime the line with the feed and the clamp. Attach the giving set to the NG tube. Unclamp the giving set and administer the feed.

If you are not using a giving set, then attach the 50 ml syringe to the top of the NG tube. Kink the NG tube and pour the feed into the syringe. Release the NG tube and allow the feed to flow into the child’s stomach. The rate of administration of the NG feed should take roughly the same length of time that it would take the infant/child to feed. This will depend on the viscosity of the feed, the size of the NG tube and the height of the syringe. Thickening agents added to the feed will lead to a slower rate of flow.

Continuous feeding

Using the aseptic non-touch technique, remove the feeding set from its packaging. Close the clamp. Attach to the feeding reservoir and the prime chamber. Unclamp and allow the feed to flow through the line to prime it. Label the line with the date and time.

Insert the feeding set into administration pump. Connect the feeding set to the nasogastric tube. Set the pump to the prescribed rate and commence the feed. Continue to observe the child closely initially and in accordance with the local policy. Any increase in the work of breathing or other changes to the child’s condition should be reported and the feed stopped at once.

Flushing out the NG tube

Once the feed is finished, the tube should be flushed out as per the local policy, this is usually with sterile water and the volume will depend on the age of the child.

All equipment should be discarded and hands should be washed.

The amount of feed given, the type of feed, the amount of flush used and how the child tolerated the feed should be documented in the child’s notes.