Overview
Definition:
Nasogastric (NG) tube placement involves inserting a flexible tube through the nose, down the esophagus, and into the stomach
Its primary purposes in pediatrics include gastric decompression, enteral feeding, medication administration, and obtaining gastric specimens
Accurate placement is paramount to prevent serious complications.
Epidemiology:
NG tube use is common in neonatal and pediatric intensive care units, with rates varying based on patient acuity
While generally safe, complications can occur in up to 5-10% of insertions, with higher rates in neonates and critically ill children
Accidental malposition accounts for a significant portion of these adverse events.
Clinical Significance:
Correct NG tube placement is crucial for safe and effective therapeutic interventions in pediatric patients
Malposition can lead to pulmonary aspiration, esophageal injury, or lack of therapeutic benefit, significantly impacting patient outcomes and potentially leading to prolonged hospital stays or increased morbidity
Understanding confirmation methods and potential complications is vital for all pediatric trainees.
Placement Technique
Preparation:
Gather necessary equipment: appropriately sized NG tube, lubricant, tape, syringe, stethoscope, pH testing strips, possibly an introducer
Explain the procedure to the child/parents and ensure adequate restraint if needed
Position the child ideally in a semi-Fowler's or supine position.
Measurement:
Measure the tube length from the tip of the nose to the earlobe, then to the xiphoid process
Mark this length on the tube with a skin marker or tape.
Insertion:
Gently lubricate the distal end of the NG tube
Insert the tube through the chosen nostril, directing it towards the nasopharynx and then downwards
If resistance is met, do not force it
withdraw and attempt reinsertion, or consider the other nostril
The child may be asked to swallow water or pacify with a pacifier to aid passage into the esophagus.
Advancement:
Advance the tube to the pre-measured mark, ensuring no coiling is visible in the nasopharynx or oropharynx
Once at the correct depth, secure the tube to the nose with tape.
Confirmation Of Placement
Initial Assessment:
Visual inspection of the tube and nasopharynx for coiling
Observing for signs of respiratory distress during insertion.
Gastric Aspirate PH:
Aspirate gastric contents using a syringe
Test the pH of the aspirate using pH strips
Gastric fluid typically has a pH of ≤ 5.5
Pleural fluid and respiratory secretions usually have a pH > 6.0.
Air Insufflation Auscultation:
Inject 5-10 mL of air through the NG tube while auscultating the epigastrium with a stethoscope
A "whooshing" sound indicates gastric placement
This method is less reliable and can give false positives.
Radiographic Confirmation:
Chest X-ray is the gold standard for confirming NG tube placement, especially in neonates and critically ill children
It clearly visualizes the tube tip within the stomach and can identify any unexpected positions, such as in the lung or esophagus
This should be performed routinely after initial placement and any time there is doubt about position.
Complications
Early Complications:
Esophageal intubation with subsequent pulmonary aspiration leading to pneumonia or ARDS
inadvertent tracheal or bronchial intubation
epistaxis
gagging, vomiting, or laryngospasm
perforation of the esophagus or pharynx
nasopharyngeal irritation or ulceration
ear pain.
Late Complications:
Tube displacement leading to misfeeding
sinusitis
gastric erosion or perforation
esophageal stricture or necrosis
tracheoesophageal fistula
blockage of the tube
accidental removal by the patient
pressure necrosis at the nares.
Prevention Strategies:
Meticulous technique during insertion
accurate measurement before insertion
frequent monitoring of tube position
regular confirmation of placement, especially before administering feeds or medications
using the gold standard radiographic confirmation initially and whenever doubt arises
proper tube securement
patient education on not manipulating the tube.
Management Of Malposition
Immediate Action:
If malposition is suspected or confirmed (e.g., respiratory symptoms, high pH aspirate, no auscultatory finding), immediately stop any feeds or medication administration
Do NOT attempt to reposition without radiographic confirmation if there is any doubt.
Confirming Malposition:
If initial checks are inconclusive or concerning, a chest X-ray is mandatory to confirm the tube's exact location.
Repositioning:
If the tube is confirmed to be in an incorrect position (e.g., esophagus, lung), it must be removed
A new NG tube should be inserted using careful technique and confirmed again using appropriate methods, preferably including radiography.
Managing Aspiration:
If aspiration has occurred, manage accordingly with supportive respiratory care, antibiotics if indicated, and close monitoring for signs of pneumonia or ARDS.
Key Points
Exam Focus:
Accurate confirmation methods (pH, X-ray) are high-yield
Common complications like aspiration and esophageal intubation
Prevention is key.
Clinical Pearls:
Always confirm placement before use
pH testing is useful but not foolproof
Radiography is the definitive confirmation method, especially in high-risk pediatric patients
Be vigilant for subtle signs of malposition.
Common Mistakes:
Relying solely on air insufflation for confirmation
forcing the tube against resistance
failing to confirm placement after repositioning or if there is any doubt
not obtaining a post-insertion chest X-ray when indicated.