Nutrition Support Routes

Nutrition support is the provision of enteral (EN) or parenteral  nutrition (PN) to treat or prevent malnutrition. Nutrition support may be used to supplement oral intake. If the individual cannot eat, it can provide all of that individual’s nutritional requirements.

A basic flow diagram for assessment of nutrition support is presented below. This flow diagram can be impacted by a variety of variables but is a good representation of how to assess for enteral or parenteral nutrition.  In consideration of more complex patients, you should use this diagram as a starting point for an assessment, not a comprehensive tool for decision making.

Enteral Nutrition

Enteral Nutrition is liquid nutrition provided through the GI tract via a tube, catheter, or stoma. This is the recommended route of nutrition support for patients with functional GI tracts.  If the gut works, use it!

EN is associated with reduced infectious complications, and helps to maintain:

• gut integrity (supports gut barrier function)
• normal digestive and absorptive capabilities
• gut-associated immune function

Indications & Contraindications

Indications for enteral nutrition include a functional GI tract and clinical conditions in which oral intake is impossible, inadequate or unsafe.

Such clinical conditions include:

• Neurological disease/ dysfunction (e.g. stroke, dysphagia, head trauma, head and neck cancer, decreased level of consciousness)
• Respiratory dysfunction (e.g. respiratory failure, mechanical ventilation)
• GI disease
  • Ileus or obstruction (feed distally)
  • Short bowel syndrome (>100 cm small bowel)
  • Low output enterocutaneous fistula (<500 mL per day)
  • Pancreatitis (small bowel feeding)

Contraindications for enteral nutrition include, but are not limited to:

• Non-operative mechanical GI obstruction
• Intractable vomiting/ diarrhea refractory to management
• Severe short bowel syndrome (<100 cm small bowel)
• Paralytic ileus
• Distal high output fistula (too distal to bypass with feeding tube)
• Severe GI bleed
• Severe GI malabsorption
• Cannot gain access to the GI tract
• Aggressive intervention not warranted/ desired

Routes of Enteral Feeding

Enteral feeding tubes may enter the body at several different sites. The choice of enteral feeding route depends on several factors, such as the intended duration of nutrition support, the patient’s condition, and any limitations to access (such as trauma or obstructions).

Sites of Delivery

Delivery Methods

Enteral Nutrition Assessment

When starting an enteral nutrition assessment, it is important to use a systematic process:

1. Complete a thorough nutrition assessment: past medical history, history of presenting illness, laboratory values, medications, nutrition history, anthropometrics, physical assessment, risk of refeeding syndrome,  medical plan, and disposition.
2. Determine feeding access: gastric vs. small bowel (duodenal vs. jejunal); short term or long term.
3. Determine protein, energy, fluid requirements.
4. Check for other sources of nutrients: IV infusions or solutions, medications.
5. Formula selection
6. Determine appropriate delivery method: continuous, cyclic, intermittent, gravity, bolus.

Depending on your patient, you may need to consider other factors in your assessment. However, this is a general representation of the assessment process.