What is the enteral feed diet?
Enteral nutrition refers to delivering nutritionally complete liquid formulas directly into the stomach or small intestine via a flexible tube. It is the preferred method of nutritional support for patients who cannot meet their needs orally, as it uses the body's natural digestive system, helping to maintain gut integrity and immune function. Unlike parenteral (intravenous) nutrition, enteral feeding utilizes the GI tract to digest and absorb nutrients, which is crucial for preventing gut atrophy and reducing infection risks. An enteral feed diet is always customized to the patient's specific nutritional requirements by a healthcare team, including a doctor and dietitian, based on their medical condition and tolerance.
Who requires an enteral feed diet?
Several medical conditions and circumstances may necessitate an enteral feed diet. Patients must have a functional GI tract to benefit from this type of nutritional support. Some common indications include:
- Neurological disorders: Conditions like stroke, Parkinson's disease, or amyotrophic lateral sclerosis (ALS) that impair the ability to swallow safely (dysphagia).
- Critical illness and injury: Patients with severe burns, trauma, or those on mechanical ventilation often have increased metabolic demands or are unable to eat sufficiently.
- Head and neck cancer: Tumors or treatments like radiotherapy can cause pain or swelling that obstructs the ability to eat orally.
- Gastrointestinal issues: Certain GI motility disorders or obstructions where the upper GI tract needs to be bypassed.
- Severe malnutrition: Prolonged anorexia or conditions that lead to severe nutritional deficiencies.
- Inability to eat safely: Conditions where there is a high risk of aspiration pneumonia, which is a life-threatening complication of food or liquid entering the lungs.
Administration of enteral feeding
The method of enteral feeding is determined by the expected duration of use and the patient's condition. A variety of tubes and delivery techniques are available.
Types of feeding tubes
- Nasogastric (NG) tube: A thin tube inserted through the nose, down the esophagus, and into the stomach. This is typically used for short-term feeding, usually less than 4 to 6 weeks.
- Gastrostomy (G) tube or Percutaneous Endoscopic Gastrostomy (PEG): A tube that goes directly into the stomach through a small incision in the abdomen. This is used for long-term feeding needs.
- Jejunostomy (J) tube or Percutaneous Endoscopic Jejunostomy (PEJ): A tube placed directly into the small intestine (jejunum). This route is used when feeding into the stomach is not tolerated or is contraindicated, for example, due to poor gastric emptying.
Delivery methods
- Bolus feeding: Administering a large volume of formula over a short period using a syringe, typically several times a day to mimic a meal schedule. This is often used with gastric tubes.
- Continuous feeding: Delivering a slow, constant rate of feeding over 8-24 hours using a feeding pump. This method is often preferred for intestinal feeding, as the small intestine cannot hold large volumes.
- Cyclic feeding: Administering continuous feeding over a set period, such as overnight, allowing the patient to have a break from the pump during the day.
Types of enteral feeding formulas
Dietitians select the appropriate formula based on the patient's caloric needs, digestive capabilities, and specific medical condition. Formulas vary in complexity and composition.
- Polymeric formulas: The most common type, these contain whole proteins, complex carbohydrates, and fats. They are suitable for patients with a functional and intact digestive system.
- Elemental or semi-elemental formulas: These contain nutrients that are already broken down into smaller components, such as peptides and free amino acids. They are easier to absorb and are used for patients with impaired digestion or malabsorption.
- Disease-specific formulas: Tailored formulas exist for patients with specific conditions like renal disease, diabetes, or those requiring immune support, with adjusted levels of protein, electrolytes, and other nutrients.
Benefits and risks of enteral feeding
| Feature | Enteral Feeding | Parenteral Feeding |
|---|---|---|
| Route of Delivery | Gastrointestinal (GI) tract via feeding tube | Intravenously (directly into the bloodstream) |
| Cost | Less expensive | More expensive |
| Risk of Infection | Lower risk, especially bloodstream infections | Higher risk, including serious bloodstream infections |
| GI Function | Preserves gut integrity and immune function | Bypasses the GI tract; gut may atrophy from disuse |
| Indications | Requires a functional GI tract | Used when the GI tract is non-functional or inaccessible |
| Complications | Aspiration, tube blockage, diarrhea, refeeding syndrome | Liver complications, metabolic abnormalities |
Potential complications and management
While generally safe, an enteral feed diet does carry potential risks that require careful monitoring and management by a healthcare team.
- Aspiration pneumonia: This occurs if formula enters the lungs, especially with gastric tubes or improper patient positioning. Elevating the head of the bed during and after feeding is crucial.
- Tube blockage: Feeds that are too thick or improper flushing can cause clogs. Regular flushing with warm water is key to prevention.
- Gastrointestinal issues: Diarrhea, nausea, and cramping are common side effects, often managed by adjusting the feed rate, volume, or formula composition.
- Refeeding syndrome: In severely malnourished patients, reintroducing nutrition too quickly can cause dangerous electrolyte imbalances. Feeding must be started slowly and monitored carefully.
- Infection and skin irritation: At the insertion site of a gastrostomy or jejunostomy tube, proper hygiene and care are essential to prevent infection and skin issues.
Conclusion
An enteral feed diet is a vital medical tool for providing complete nutritional support to individuals who cannot eat orally but have a working digestive system. Tailored formulas and various administration methods ensure optimal nutrient delivery, which is more physiological and generally safer than intravenous feeding. While potential complications like aspiration and tube issues exist, they can be effectively managed with proper medical supervision. For anyone considering or beginning enteral nutrition, consultation with a multidisciplinary healthcare team is essential to ensure the plan is safe, effective, and tailored to their specific health needs. For more comprehensive information, the NCBI Bookshelf provides extensive resources on enteral feeding, including its indications and management.
