Information Hub
Understanding Enteral and Parenteral nutrition — written for patients, following NHS guidelines.
Enteral Nutrition (EN)
Enteral nutrition delivers liquid feed directly into the gut through a tube. It is used when someone cannot eat enough by mouth but their digestive system still works.
Based on BAPEN standards for Home Enteral Nutrition (HEN).
Types of enteral tubes
A fine tube passed through the nose, down the throat, into the stomach. Used short-term (weeks). Must be checked before every feed using pH testing strips.
A tube inserted surgically through the abdominal wall into the stomach. Used long-term. Held in place by an internal bumper or balloon.
Delivers feed past the stomach directly into the small intestine (jejunum). Used when the stomach cannot tolerate feed (e.g. gastroparesis).
A discreet button-style device flush with the skin. An extension set is attached for feeds. Replaced every 6–12 months.
Parenteral Nutrition (PN / TPN)
Parenteral nutrition delivers complete nutrition directly into the bloodstream through a central venous line. It bypasses the digestive system entirely.
Total Parenteral Nutrition (TPN) provides all nutrition intravenously. It is used when the gut cannot absorb enough nutrition.
Based on BAPEN standards for Home Parenteral Nutrition (HPN) and NHS England specialised commissioning guidance.
Types of venous access
A tunnelled central venous catheter (CVC) surgically placed under the skin. The external end sits on the chest. Most common for long-term HPN. Can be single or double lumen.
Inserted through a vein in the arm, threaded to a large central vein. Used medium-term. Requires careful arm care.
A device placed fully under the skin with a small reservoir accessed by a special needle. Very discreet. Requires needle access for each use.
Short-term PN through a peripheral cannula. Limited to lower concentration solutions. Used in hospital or for short-term home support.
What's in a TPN bag?
TPN bags are individually compounded (made to order) by a specialist IV pharmacy to match your nutritional requirements. A standard TPN bag contains:
Home monitoring — what the NHS expects
Patients on home PN are monitored regularly by their nutrition support team. The following is based on BAPEN and NHS England guidance:
- Weight (same time, same scales)
- Temperature (daily if unwell)
- Fluid balance (input vs output)
- Blood tests (electrolytes, LFTs, glucose)
- Temperature >38°C or <36°C
- Weight change >2 kg in a week
- Redness or discharge at line/tube site
- Feeling unwell during or after infusion
Useful organisations
The UK patient charity for people on tube and IV feeding. Peer support, helpline, and events.
Visit PINNT →British Association for Parenteral and Enteral Nutrition — clinical guidelines and standards.
Visit BAPEN →Home Parenteral Nutrition service information and commissioning guidance.
Visit NHS.uk →