Enteral nutrition

Overview of Treatment

Enteral Nutrition is a method of delivering nutrients directly through the gastrointestinal tract, primarily used for patients who cannot ingest sufficient nutrients orally. This therapy utilizes the absorptive function of the gut, administering specialized nutritional formulas via tubes into the stomach or intestines to maintain nutritional balance and physiological functions. Compared to total parenteral nutrition, enteral nutrition helps preserve intestinal barrier function and reduces infection risk, making it a vital component of modern clinical nutritional support.

Types and Mechanisms of Treatment

Based on the route of administration, there are three types:

• Nasal gastric or nasal intestinal tubes: suitable for short-term use
• Gastric feeding tubes: common choice for long-term use
• Jejunal feeding tubes: preferred when avoiding gastric retention

Nutrition solutions contain amino acids, lipid emulsions, carbohydrates, and vitamins. After absorption through the intestinal mucosa into the portal system, they simulate normal digestion. This process stimulates intestinal hormone secretion and promotes blood flow and peristalsis.

Indications

Mainly indicated for:

• Neurogenic dysphagia (e.g., stroke, Parkinson’s disease)
• Postoperative or radiotherapy period for head and neck cancers
• Severe malnutrition requiring rapid correction
• Short bowel syndrome or intestinal malabsorption
• Patients in intensive care units to maintain gut function

For patients expected to require nutritional support for more than 7 days, guidelines recommend prioritizing enteral nutrition.

Administration Methods and Dosage

Initial administration typically begins with low concentration and slow rate (e.g., 20 mL/hr), gradually increasing to the target dose based on patient tolerance. The recommended daily caloric intake for adults ranges from 20-35 kcal/kg of body weight, with protein intake usually 1.2-1.5 g/kg. Long-term users should have their nutritional status evaluated every 3-6 months, with adjustments to the formula as needed.

Benefits and Advantages

Core benefits include:

• Reducing hospital-acquired infection rates by 30-50%
• Maintaining gut microbiota balance and immune function
• Reducing hepatic metabolic burden compared to total parenteral nutrition

Additionally, patients can remain mobile while awake, improving quality of life. Studies show that enteral nutrition can shorten hospital stays, especially in burn and trauma patients.

Risks and Side Effects

Common side effects include:

• Diarrhea or bloating (incidence approximately 25-40%)
• Nasal and pharyngeal mucosal injury
• Tube blockage or displacement

Serious complications include aspiration pneumonia, intestinal intussusception, or tube-related infections, requiring close monitoring of gastric residuals and vital signs.

Precautions and Contraindications

Contraindications include:

• Complete bowel obstruction or perforation
• Severe diarrhea or paralytic ileus
• Esophageal variceal bleeding

During use, the following should be maintained:

• Daily cleaning of tube connections
• Every 4 hours, aspirate gastric residuals
• Regular assessment of liver and kidney function indicators

Absolute contraindication is administering without monitoring in patients with impaired consciousness.

Interactions with Other Treatments

When combined with antibiotics, be aware that broad-spectrum antibiotics may disrupt gut flora; probiotic supplementation is recommended. Chemotherapy drugs may delay gastrointestinal motility, requiring adjustment of infusion rates. When used with immunosuppressants, monitor blood glucose levels, as nutritional formulas may affect drug pharmacokinetics.

Effectiveness and Evidence

Multicenter studies show that postoperative patients receiving enteral nutrition can reduce infectious complications by up to 40%. The 2017 ESPEN guidelines state that initiating enteral nutrition within 48 hours in critically ill patients improves prognosis. However, elderly patients may require lower initial doses due to weaker gut metabolic capacity.

Alternative Options

Alternatives include:

• Total parenteral nutrition: suitable for patients with non-functional intestines
• Oral nutritional supplements: suitable for mild intake deficiencies
• Gut training programs: gradual postoperative reintroduction of oral intake

While total parenteral nutrition bypasses the digestive tract entirely, it may increase the risk of hepatic steatosis. Oral supplements are only suitable for some patients with intake barriers and cannot fully replace tube feeding.

 

Frequently Asked Questions

How to determine if the enteral nutrition infusion rate is appropriate?

The infusion rate should be adjusted based on the patient’s gut adaptation. Start with a low rate (e.g., 20-30 mL/hour) and observe for bloating or vomiting. If tolerated, increase by 10-20 mL/hour every 2-4 hours, aiming for a final rate of 60-120 mL/hour. Regular assessment by nursing staff is essential, and adjustments should be made in consultation with the medical team.

What should be done if the feeding tube becomes blocked?

If blockage occurs, flush the tube with 10-20 mL of warm water using pulsatile pressure. If unresolved, verify tube position or check if the formula has clumped due to inadequate mixing. Severe blockages require stopping infusion immediately and contacting healthcare providers for repositioning or replacement of the tube to prevent intestinal pressure.

Can patients on enteral nutrition also eat solid foods?

After medical assessment, some patients may gradually try small amounts of low-fiber foods alongside enteral nutrition. Total caloric intake should be monitored to avoid excess or deficiency. Start with clear liquids and observe tolerance. Patients with severe swallowing difficulties or poor digestion may need to suspend solid foods temporarily.

What nutritional imbalances can long-term enteral nutrition cause, and how to prevent them?

Prolonged use may lead to electrolyte imbalances, osteoporosis, or vitamin deficiencies. Regular blood tests should be conducted to monitor electrolytes and nutritional markers, with formula adjustments as needed. Bone density scans every 3-6 months are recommended. Supplementation with calcium, vitamin D, or specific micronutrients may be advised to prevent deficiencies.

How to maintain the feeding tube to prevent infections during enteral nutrition?

Daily disinfection of the skin around the tube with 75% alcohol is necessary, along with regular replacement of connection devices. After feeding, flush the tube with 30 mL of warm water using pulsatile pressure, then seal with heparin saline to prevent clot formation. If fever, redness, swelling, or abnormal discharge occurs at the tube site, discontinue use and seek medical attention. Antibiotic therapy or tube replacement may be required.