A nasogastric tube (NGT) is a flexible tube inserted through the nose, down the esophagus, and into the stomach. The feeding administered through an NGT is known as enteral nutrition. This refers to any method of providing nutrients to the body through the gastrointestinal (GI) tract. Enteral feeding is a preferred nutritional method over parenteral nutrition, which bypasses the GI tract entirely, because it is more physiological, simpler, and less prone to complications.
Understanding Enteral Nutrition
Enteral nutrition is a broad term for nutritional support that uses the gut. The NGT is just one of several access routes for this process. It is typically used for short-term feeding, generally lasting for a few weeks to months, until the patient can transition back to oral feeding or requires a more permanent access method. For many patients, NGT feeding is a life-sustaining treatment, preventing malnutrition and dehydration when oral intake is compromised.
Methods of NGT Feeding
There are several ways to administer feeding through an NGT, and the best method depends on the patient's nutritional needs, tolerance, and overall health status.
Bolus Feeding
This method involves delivering a specific volume of formula over a short period, typically 15–30 minutes, several times a day. It is often done using a syringe and gravity.
- Advantages: Mimics a normal eating schedule, allowing for more time between feedings for physical activity or other daily routines.
- Disadvantages: Can cause cramping, bloating, or diarrhea if administered too quickly.
Continuous Feeding
With this method, a feeding pump gradually and continuously delivers a constant rate of formula over many hours, often overnight.
- Advantages: It can be better tolerated by patients who experience bloating or discomfort with bolus feeding.
- Disadvantages: Requires the use of a pump and may limit patient mobility during administration.
Intermittent Gravity Feeding
This is a variation of bolus feeding where the feed bag is hung and flows by gravity. The flow rate is controlled by the height of the bag and a roller clamp. This can take longer than syringe-based bolus feeding but is often a smooth process.
When is a Nasogastric Tube Used?
NGT feeding is indicated for patients who have a functional GI tract but are unable to safely consume adequate nutrition orally. Common reasons include:
- Dysphagia: Difficulty swallowing, often resulting from a stroke, neurological disease, or head and neck cancer.
- Decreased Level of Consciousness: For patients who are in a coma or are heavily sedated on a ventilator.
- Short-Term Needs: After major surgery, trauma, or for specific medical conditions where a temporary alternative to oral intake is needed.
- Inadequate Oral Intake: To provide supplemental calories for patients who cannot consume enough by mouth to meet their nutritional requirements.
NGT vs. Other Feeding Tubes: A Comparison
| Feature | Nasogastric Tube (NGT) | Gastrostomy Tube (G-tube) | Jejunostomy Tube (J-tube) |
|---|---|---|---|
| Placement | Through the nose, into the stomach | Surgically inserted directly into the stomach through the abdominal wall | Surgically inserted directly into the jejunum (small intestine) through the abdominal wall |
| Duration of Use | Short-term (weeks to months) | Long-term (more than six weeks) | Long-term (more than six weeks) |
| Procedure | Nonsurgical, typically performed at bedside | Surgical procedure (e.g., PEG) | Surgical procedure |
| Indications | Swallowing difficulties, reduced consciousness | Long-term feeding, often for patients with dysphagia | When feeding into the stomach is not tolerated, such as with severe reflux |
Best Practices and Potential Complications
Proper management is crucial to minimize complications associated with NGT feeding. The most serious risk is aspirating formula into the lungs due to tube misplacement.
Best Practices
- Confirm Placement: Verify tube position after initial insertion and before each feed by checking external tube markings and testing gastric aspirate pH. An X-ray is the most definitive method after initial placement.
- Head of Bed Elevation: Keep the patient's head elevated at 30–45 degrees during and for at least an hour after feeding to prevent reflux and aspiration.
- Regular Flushing: Flush the tube with water before and after feedings and medications to prevent clogging. A 50mL syringe is commonly used.
- Tube Care: Ensure the tube is secured properly to the nose and cheek to prevent dislodgment. Clean the nasal area daily to prevent skin irritation.
Potential Complications
- Dislodgment: The tube can become dislodged, especially in confused or agitated patients.
- Aspiration Pneumonia: Inadvertent delivery of feed into the lungs, which is a life-threatening risk.
- Tube Blockage: Can occur if the tube is not flushed regularly or if medications are not properly administered.
- Irritation: Nasal and throat irritation, skin breakdown at the insertion site, or hoarseness can occur.
Conclusion
In conclusion, an NGT provides essential enteral nutrition for patients unable to eat or swallow safely. This temporary feeding method, which relies on the function of the digestive system, is administered via bolus, continuous, or intermittent gravity methods. Through careful adherence to best practices, such as proper placement verification and diligent tube care, NGT feeding can effectively manage nutritional needs while minimizing risks. The decision to use an NGT is made by a medical team and depends on the patient's specific condition and prognosis.
