This guide explains the procedure for inserting and maintaining nasogastric (NG) tubes, covering their clinical purposes, insertion techniques, placement verification, and essential patient care interventions.
Nasogastric (NG) tube insertion is a critical clinical procedure used to manage patients with complex gastrointestinal, nutritional, or emergency needs. A nasogastric tube is a flexible tube passed through the patient’s nares (nostrils), through the nasopharynx, and down the esophagus into the stomach. Because this procedure involves invasive access to the digestive tract, it must be performed under a physician's order and requires precise nursing assessment and intervention to ensure patient safety and therapeutic efficacy.
Clinical Purposes of NG Tube Therapy
The decision to insert an NG tube is driven by specific clinical indications. Depending on the patient's condition, the tube may serve one of four primary therapeutic roles:
Decompression: This is used to relieve pressure within the stomach by removing accumulated gas or fluids. This is particularly vital in cases of vomiting, gastric distension, or bowel obstructions. Decompression helps promote abdominal comfort and allows surgical sites (anastomoses) to heal without the stress of distension.
Enteral Feeding: For patients unable to consume food orally—due to unconsciousness, difficulty swallowing (dysphagia), or neurological disorders—the NG tube provides a route for nutrients via the gastrointestinal tract.
Compression: The tube can be used to apply pressure to control bleeding or manage specific gastric conditions.
Lavage/Irrigation: In emergency situations, such as poisoning or drug overdose, the tube is used to wash out the stomach (lavage) to remove toxic substances.
Clinical Note: Indications for Use
NG tubes are frequently indicated for patients experiencing delayed gastric emptying, esophageal reflux, or those at high risk for aspiration, such as patients with a history of aspiration pneumonia. Other indications include critical illness, major surgery, trauma (including burns), and severe depression.
Diagram illustrating the path of a nasogastric tube through the nasal cavity, pharynx, esophagus, and into the stomach.
Nasogastric Tube Insertion
The insertion process requires careful preparation and assessment to minimize discomfort and prevent complications like tube migration into the lungs.
Assessment and Preparation
Before insertion, the nurse must assess the patient's nasal patency by checking for a deviated septum, nasal polyps, or obstructions. It is also essential to check the medical record for the physician's order regarding the type of tube and whether it should be attached to suction or straight drainage.
The Insertion Procedure
Measurement: Accurate estimation of the tube length is critical to ensure the tip reaches the stomach rather than the esophagus or lungs.
Technique: A clean technique is recommended. To reduce discomfort, the nurse may examine the nares for skin breakdown and place the patient in a high-Fowler's position.
Assistance: During insertion, encouraging the patient to swallow can help facilitate the passage of the tube through the esophagus.
Verifying Placement
Verification is the most critical safety step. Placement must be verified immediately after insertion and before any administration of medications, feedings, or irrigations. Methods include:
Auscultation: Listening for air bolus insertion over the abdomen.
pH Testing: Aspirating gastric contents to check for a pH between 1.0 and 4.0.
X-ray: An abdominal X-ray is considered a definitive method for verifying position.
Diagram illustrating the verification of Nasogastric (NG) tube placement through immediate post-insertion checks and pH testing of gastric aspirate.
Maintaining Patency and Patient Care
Once the tube is in place, the nurse's priority shifts to maintaining patency—ensuring the tube remains open and functional.
Nursing Interventions for Maintenance
Flushing: To prevent clogging from formula or medication, the tube should be flushed with 30–60 mL of water before and after feedings, and before and after administering medications.
Irrigation: If the tube becomes blocked, irrigation may be necessary, though nurses must never irrigate a patient who has had stomach surgery without a specific physician's order.
Skin Integrity: The pressure of the tube can cause irritation to the nasal mucosa or even esophageal ulceration. Nurses should provide frequent oral and nasal hygiene and re-tape the tube if skin breakdown occurs.
Positioning: To prevent aspiration during enteral feeding, the head of the bed must be elevated at least 30–45 degrees during the feed and for at least 30 to 60 minutes afterward.
Exam Tip: Complications to Watch For
Always monitor patients with NG tubes for signs of pulmonary aspiration, such as fever, shortness of breath (SOB), or pulmonary congestion. If these occur, perform a respiratory assessment and prepare for a chest X-ray.
Nutritional Considerations and Medical Nutrition Therapy
NG tubes are often a component of Medical Nutrition Therapy, which provides restorative care for patients with specific conditions such as diabetes mellitus, cardiovascular diseases, cancer, and HIV.
When managing enteral nutrition, nurses must understand the nutritional needs of the patient. For example, in patients with diabetes, the goal is to maintain serum glucose levels as close to normal as possible by balancing food intake with activity and medication. In cases of renal failure, diets may require strict restrictions on protein, sodium, potassium, and phosphorus.
Nurses also utilize assessment tools like the clock-face method to identify the location and proportion of food on a patient's plate, ensuring adequate intake.
Related Clinical Concepts: Bowel Management
While NG tubes manage the upper GI tract, nurses must also be proficient in managing the lower GI tract, especially when NG tubes are used in conjunction with other interventions.
Digital Removal of Stool
In cases of fecal impaction—where stool is stuck in the rectum and too large to pass voluntarily—a physician's order is required for the digital removal of stool. This involves using a finger to break up the mass and remove it in sections. This procedure can be uncomfortable and carries risks, such as irritation, bleeding, or stimulation of the vagus nerve.
Summary of NG Tube Nursing Diagnoses
Common nursing diagnoses for patients requiring NG tube management include:
Risk for aspiration.
Imbalanced nutrition: less than or more than body requirements.
Impaired oral mucus membrane (due to drying from mouth breathing).
Impaired tissue integrity (due to nasal pressure).
Deficient fluid volume (associated with the removal of gastric secretions).
Keep reading for free.
Create an account to finish this reading and make it part of your study routine.