What is Enteral Nutrition?
As we all know, everyone needs food to survive. In some cases, individuals are not able to intake any or enough food on their own. One way to provide nourishment for these individuals is with “enteral nutrition” or more commonly known as “tube feedings.” Another way to provide nourishment to individuals who cannot orally ingest food is through “parenteral nutrition,” which is providing nutrients through a vein directly into the blood stream. These two methods are very different and as the saying goes, “use it – or lose it.” In this instance I am referring to the gut and digestive system – if the gut works, then use it!
Tube feeding formulas are in a liquid form that contains protein, carbohydrates, fats, vitamins and minerals. They are many varieties of formulas to meet different needs and the dietitian performs a variety of calculations to determine which formula will be best for the patient. This formula is given through a tube and then normal digestion can occur in the stomach and intestines.
What Conditions Require Enteral Nutrition?
Any condition that alters a patients’ ability to swallow can lead to the implementation of enteral nutrition as long as the gastrointestinal (GI) system is still working. Also, if a patient cannot take in adequate nutrition due to impaired nutrient ingestion, digestion, absorption, or metabolism then enteral nutrition can be used. Common conditions include:
- Neurological disorders
- Facial/oral/esophageal trauma
- Respiratory failure (the need for a ventilator)
- Traumatic brain injuries
- Cystic fibrosis
- Dysphasia (common after a stroke)
- Major burns, trauma, or wounds
What are the Considerations when Choosing a Formula?
- Digestibility/availability of nutrients
- Nutrition adequacy to meet needs
- Osmolality (fluid needs)
- Ease of use
What are the Different Formula Categories?
- Standard – these contain nutrients that are intact (most often used)
- Elemental – partially or completely hydrolyzed (broken down) nutrients
- Disease specific – designed for a wide variety of disease states (renal, diabetes, etc.)
- Modular – allows for the addition of nutrient content
How is the Tube Feeding Supplied?
There are multiple different placements options when considering a tube feed depending on the specific needs of each patient. The greater use of the GI system that can be tolerated by the patient is the route that is used in most cases. Estimated length of time the feeding tube will be required helps to determine the route. Another important factor is the risk of aspiration. If there is a high risk for aspiration then the patient will need the tube to continue past the pyloric sphincter.
Short Term (<3 weeks):
- Orogastric – tube enters through the mouth and goes into the stomach
- Nasogastric – tube enters through the nose and goes into the stomach
- Nasoduodenal – tube enters through the nose and goes into the duodenum (first part of the small intestine)
- Nasojejunal – tube enters through the nose and goes into the jejunum (second part of the small intestine)
Long Term (>4-8 weeks):
- Gastrostomy – tube enters directly through the skin into the stomach
- Jejunostomy – tube enters directly through the skin into the jejunum (second part of the small intestine)
What are the Delivery Methods of Enteral Nutrition?
- Delivered at a continuous/steady rate that is controlled via a feeding pump
- Most often used when feeding into the small bowel (intestine)
- Preferred for critically ill patients and those unable to tolerate bolus or intermittent feedings
Bolus or Intermittent:
- Bolus – last from a few minutes to 20 minutes and given via a syringe
- Intermittent – last 20-60 minutes and given via a gravity drip
- Preferred type of feeding for gastric routes (into the stomach) but not well tolerated in the intestine
- Used for ambulatory patients and patients in their home
- Fluid ranges between 240-480 mL
Cyclic or Nocturnal:
- Used as a transition from enteral feedings to an oral (normal) diet
- Rate can reach up to 150 mL/hour
- Commonly used for patients in their home
- They are infused continuously for 10-12 hours (typically overnight) to allow for greater oral intake during the day
What are the Complications of Enteral Nutrition?
While tube feeding is a generally safe option, there are potential risks associate with it. For example, patients may experience abdominal discomfort, nausea, vomiting, abdominal distention, constipation, diarrhea, or aspiration. There are ways to reduce this risk that health providers should always abide by.