Contraindications for Nasogastric Tube Placement
Nasal access should be avoided in individuals with abnormal nasal anatomy, facial trauma, or recent oronasal surgery, while the only absolute contraindication for enteral feeding access is mechanical small bowel obstruction (unless placed for decompression). 1
Absolute Contraindications
The evidence is clear that there are very few absolute contraindications specific to NG tube placement:
- Mechanical small bowel obstruction is the only absolute contraindication when the tube is intended for feeding purposes (decompression is still permissible) 1
- Abnormal nasal anatomy that prevents safe passage 1
- Facial trauma involving the nasal passages or skull base 1
- Recent oronasal surgery where tube placement could disrupt healing 1
Relative Contraindications and High-Risk Situations
Several clinical scenarios warrant extreme caution but are not absolute contraindications:
Hemodynamic and Respiratory Compromise
- Hemodynamic instability requires stabilization before elective placement 1
- Respiratory compromise may worsen with positioning and potential aspiration risk during insertion 2
- Altered consciousness or absent gag/cough reflex significantly increases risk of inadvertent bronchial insertion 3
Gastrointestinal Bleeding
- Active GI bleeding from peptic ulcer represents a relative contraindication 1
- Esophageal varices are not absolute contraindications but increase aspiration risk and make placement more difficult 1
Coagulopathy Considerations
While more relevant for percutaneous tubes, coagulopathy should be corrected when feasible:
Critical Safety Considerations
Risk of Bronchial Insertion
Patients with NG tubes have approximately 9 times higher risk of aspiration than those without tubes, and inadvertent bronchial insertion can be fatal. 4 This risk is particularly elevated in:
- ICU patients 3
- Patients with altered consciousness 3
- Those with impaired gag or swallow reflexes 4, 3
- Importantly, endotracheal tubes do NOT prevent inadvertent bronchial insertion 4
Position Verification is Mandatory
Each institution must have a dedicated protocol for confirming correct NG tube placement that includes radiography, pH testing of aspirate, and end-tidal CO2 monitoring—but NOT auscultation alone. 3 The traditional "whooshing sound" method is unreliable and no longer recommended 5. Radiographic confirmation is the gold standard and is mandatory in high-risk patients 3, 6.
Rare but Serious Complications
Case reports document devastating complications including:
- Nasopharyngeal perforation with mediastinal passage into pleural space 7
- Esophagogastric submucosal tunneling 5
- Empyema and pneumothorax from misplacement 7
These complications emphasize that resistance during insertion should never be ignored, and emerging clinical signs after placement (abnormal drainage, hypotension, respiratory distress) warrant immediate investigation. 5
Special Populations
- Severe dysmotility and esophageal varices complicate but do not absolutely contraindicate placement; adequate sedation with anesthesia support can facilitate safe insertion 1
- History of gastrointestinal disease should be carefully considered as it may increase complication risk 5
Duration of Use
NG tubes should be reevaluated daily and removed as soon as possible. 4 For patients requiring enteral nutrition beyond 4-6 weeks, percutaneous gastrostomy should be considered as it has lower rates of ventilator-associated pneumonia 4. Small-bore tubes (8 French) are preferred to reduce pressure ulcer risk 4.