Nasogastric tube insertion animated demonstration
The equipment required for this procedure includes:
Nasogastric tube of appropriate size and type (fine bore or Ryle’s type)
Lubrication jelly or water
Gloves and plastic apron
Adhesive tape/purpose-made nose adhesive
30 mL enteric (feeding) syringe
Drainage bag or connection tubing
Universal pH paper.
There are two types of nasogastric tube: fine bore feeding tubes and wide bore tubes, also known as Ryle’s tubes. Fine bore (8-12 French) tubes cause less discomfort and are easier to insert. They are predominantly used for enteral feeding because they are too small to be effective for decompression. Wider bore (Ryle’s) tubes (14-18 French) are used to decompress the stomach.
Basal skull fracture: you should not use a nasogastric tube in patients with a basal skull fracture as it may lead to intracranial placement
Previous trans-ethmoidal/trans-sphenoidal neurosurgery
Oesophageal anastomosis and gastric surgery in postoperative patients (unless a specialist performs insertion with direct endoscopic insertion)
Upper gastrointestinal tract perforation
These conditions make passage of a nasogastric tube more difficult or more risky. Advice from an experienced specialist should be sought.
Small and large bowel obstruction
Gastric outlet obstruction
Acute gastric dilation
To prevent aspiration from gastro-oesophageal reflux distal to an oesophageal anastomosis (placed under direct vision intra-operatively)
Postoperative gastrointestinal surgery (placed intra-operatively). These can also be naso-jejunal tubes, where the end lies more distally in the jejunum.
It is common for the tube to be dislodged or removed in a confused or agitated patient
Epistaxis may occur
Malposition followed by aspiration of fluid into the bronchial tree may result in aspiration pneumonia and severe respiratory compromise
Feeding tubes may become blocked with the feed substrate requiring repositioning if the blockage cannot be cleared with clear fluids or effervescent fluids
Pneumothorax. Sixty-five reports of pneumothoraces caused by nasogastric tube insertion were reported to NHS Improvement over two years
If malposition occurs in a patient with a base of skull fracture, then intracranial positioning may occur. For this reason, you should not use nasogastric tubes in patients with a suspected or confirmed basal skull fracture
You can avoid most complications by ensuring correct positioning of the nasogastric tube.
Check the position of the nasogastric tube. You should follow your organisation’s local guidelines as to which method you should use. Methods include:
Aspiration - aspirate gastric fluid and test on pH paper. Gastric fluid should be acidic, with a pH between 1 and 5.5. NHS England advises that you should test aspirate on CE marked pH indicator paper for use on human gastric aspirate
Chest x-ray - if the pH is above 5.5, or you are unable to aspirate gastric fluid, then request a chest x-ray. The x-ray should show the radio-opaque nasogastric tube following the line of the oesophagus (and avoiding the contours of the bronchi), bisecting the carina, and crossing the diaphragm in the midline, as well as the tip of the tube being visible below the hemi-diaphragm. It is important to note that, because the diaphragm is domed, it is possible for the tip of the nasogastric tube to appear to be below the diaphragm but still to be positioned in the lung. Therefore, it is important not to use this one criterion on its own to assess for correct positioning.
The tube position should be re-checked:
Before each administration of feed
Before drug administration, if not being used for feeding
Following an episode of vomiting, retching, or coughing
If there is a risk of displacement (e.g., the tape securing the tube has come loose, or the length of tube at the nostril is less than previously documented)
If the patient has unexplained respiratory symptoms or reduced oxygen saturations.