Nasogastric Tube (NG) placement


The most common cause of NG error (leading to misplacement into the trachea) is misinterpretation of x-rays.

Our agreed policy is:

  • pH testing should be used as the 1st line test method (with pH between 1 and 5.5 as the safe range)
  • X-ray should only be used as a 2nd line test
  • The clinician requesting x-ray must confirm, on the request, the results of pH testing before an x-ray will be completed


Primarily intended for short-term (<72hrs) therapeutic or Dx uses. Often inserted in patients immediately after major surgery to help keep the stomach empty and prevent postop vomiting and used to feed and administer meds in critically ill patients.

Made from:

  • PUR – currently using Nutricare NG tubes in Cork hospitals. Can remain in situ for up to 90 days
  • PVC – not ideal as need to be changed every 7 days


Most NG tubes range in size from 12 to 18 F for adults are 100 to 125cm long

Gather all the equipment at the bedside:

  • Kidney bowl and tissues
  • Non-sterile gloves
  • pH indicator strips
  • Syringes with Enfit connection
  • Tape &plusnm; safety pin to secure tube
  • Sterile water to flush after placement and removal of wire
  • Towel, tissues, water-soluble lubricant
  • An aspiration set
  • Ice chips or a cup of water with a straw
  • If suction will be used, make sure it is set up and working properly


  • Explain to your patient that you will gently insert the tube into their stomach. Explain they may experience momentary discomfort, such as coughing, gagging, or tearing, but it is essential that s/he swallow as directed to ease tube insertion
  • Measure (and measure again)
  • Length = nose, behind earlobe, xiphoid and add 5cm, mark with a piece of tape (NEX+5 usually 55-65cm)
  • Check which nostril is most patent
  • Sit patient up with head/shoulder supported on a pillow
  • Keep head neutral (not extended)
  • Keep kidney dish nearby
  • Non-sterile gloves
  • Curl tube tip and lubricate distal 10cm to ease insertion
  • With the curve pointing downward (hold behind the lubricated bit), carefully insert the tube along the floor of the nostril, on the lateral side
  • Once at nasopharynx, patient may gag/cough ask him to flex his neck slightly
  • Ask him/her to swallow (± sips of water)
  • Persistent cough/difficulty talking? in trachea - withdraw and try again
  • Ask for help (not fair on patient) if you fail easy passage more that a couple of times
  • Check position by recording pH (must be <5.5) in clinical notes
  • Do not confirm placement with audible 'whoosh' on auscultation
  • If in doubt confirm placement with a CXR
  • Once position confirmed, flush tube with water and remove guidewire
  • Once placement confirmed, secure with AMT bridle or tape equivalent

Removing the tube:

  • Reassure patient (much easier than insertion) but potential gag
  • Non-sterile gloves
  • Disconnect feeding bags or suction
  • Sit patient up, towel on chest
  • Remove securing device
  • Withdraw tube with single continuous gentle traction onto towel
  • Clean up after you

Content by Dr Íomhar O' Sullivan. Last review Dr ÍOS 27/08/23.