Correct NG tube placement and NPSA guidance 

1. Correct Placement of an NG Tube 

Proper placement of an NG tube is crucial because misplacement (e.g., into the lungs) can cause serious harm. 

A. Methods to Confirm Placement – always follow local guidance.

pH testing of aspirate (preferred first-line check) 

Aspirate a small amount of stomach contents. 

Test the pH: 
pH ≤ 5.5 → likely in the stomach 
pH > 6 → could be in the lungs or intestines; do not feed 
Remember: medications like antacids or PPIs can raise gastric pH, which may make this less reliable. 

Radiographic confirmation (gold standard if uncertain or pH not possible) 

Chest X-ray is the definitive method to confirm placement. 
The tip should be visualized below the diaphragm in the stomach. 
This is especially required before feeding or giving medications if there is any doubt about placement. 
Other adjunct checks (less reliable, do not rely on them alone) 

Auscultation (“whoosh test”) – injecting air and listening over the stomach: not recommended

Visual inspection of aspirate – can help but is not definitive. 

B. Correct Tube Position 

Tip of the NG tube should be in the stomach (or post-pyloric if specifically indicated). 
Confirm by aspirate pH or X-ray, as above. 
Misplacement into the trachea/bronchi/lungs is the main safety concern. 

2. NPSA Guidelines for NG Tube Safety 

The NPSA Rapid Response Report (2005/2011 updates) focused on NG tube misplacement causing harm, emphasizing: 

Key Points: 

Do not rely on a single unverified method: 
Never feed, flush, or medicate through an NG tube without confirming placement. 

pH testing first-line: 
Aspirate stomach contents and test pH. 
Use a pH cutoff ≤5.5 (or ≤5 in adults) to confirm gastric placement. 

X-ray confirmation if: 
Aspirate cannot be obtained 
pH is above cutoff 
Patient is high risk (e.g., ventilated, altered consciousness) 

Documentation and labelling: 
Document NG tube size, length inserted, method of confirmation. 
Clearly document after confirmation: e.g., “NG tube placement confirmed – safe to feed”. This must be documented by an appropriately qualified healthcare professional 

Ongoing checks: 
Check tube position before each feed or medication administration, especially if patient movement, excess coughing or vomiting has occurred. 

Summary  

Key safety points: 

Never administer feed/meds before confirmation. 
Always document confirmation method. 
Remove guidewire after tube confirmation before use