Nasogastric Tubes

  • Ileus or intestinal obstruction can lead to the accumulation of gases and liquids in the gastrointestinal (GI) tract. Unless these are removed, vomiting may occur and a significant risk of aspiration is present.


  • Adynamic ileus
  • Small bowel or gastric outlet obstruction
  • Severe burns or polytrauma
  • After intestinal surgery with anastomosis
  • To facilitate gastric lavage for bleeding or poison ingestion


  • In cases with known or suspected facial fracture, the tube may be placed via the mouth


  • Known or suspected cervical spine injury


  • 16 to 18 Fr NG tube
  • Lubricant jelly
  • Topical nasal vasoconstrictor / anaesthetic such as co-phenylephrine
  • Emesis bag
  • Catheter tip syringe
  • Suction apparatus
  • Gloves and eye protection
  • A small cup with water for the patient to sip through
  • Benzoin and tape to secure the tube once placed
  • Stethoscope to confirm placement


  • It is safer to place an NG tube in a conscious patient who can cooperate with the procedure.
  • The risk of placement in an unconscious or a paralyzed patient is misplacement into the lungs.


  • None, or topical lidocaine administered to the nares


  • Prepare the patient.
    • Explain the procedure.
    • Explain the risks and alternatives.
    • Answer any questions.
  • Position the patient.
    • Upright or decubitus, neck flexed
  • Estimate the tube length.
    • Measure the distance from the patient’s ear to the umbilicus; this is a good estimate of the needed length.
  • Premedicate the patient.
    • Choose a nostril. Select the most patent one.
    • Spray topical anesthetic to the back of the throat.
    • Apply vasoconstrictor and topical anesthetic to the nasal mucosa.
    • Apply lubricating jelly liberally to the tip of the tube and along the length of the tube as well.
  • Have the suction apparatus turned on with the tonsil tip attache
    • Have the patient hold an emesis basin.
  • Insert the tube.
    • With the patient’s neck flexed (confirm that there is no cervical spine injury), insert the tube into the nostril.
    • Aim straight back toward the occiput.
    • Apply firm, constant pressure to the tube.
    • Have the patient hold the cup of water and take small sips and swallow as you apply pressure. Continue to advance the tube to the desired length.
      • A good guideline is to advance the tube until two black lines on the tube are visible out of the nares.
      • The nose should be between the second and third black lines.
    • Anticipate some gagging during placement.
      • This may be decreased by spraying additional topical anesthetic to the back of the throat.
  • If the tube does not pass easily
    • If the tube coils in the mouth or esophagus, chill the tube in some ice to stiffen it.
    • If the tube does not pass at all, try the other nostril.
    • If, during advancement, the patient begins to cough, withdraw immediately. This indicates misplacement into the lung.
  • Once the tube is inserted
    • Hold it firmly in place close to the nostril; often, this requires steadying your hand against the patient’s nose.
    • Attach the catheter tip syringe to the tube, and inject 30 to 60 mL of air into the tube. Listen over the epigastrium for the rumbling of the air into the stomach.
    • Aspirate back on the syringe to confirm the efflux of gastric fluid. Check stomach contents for pH.
    • Secure the tube to the nose with benzoin and tape.
      • Avoid taping the tube in such a way that pressure is applied to the nostril; this is a common cause of necrosis of the nares.
    • Be sure to tape the tube down to a second site, such as the patient’s forehead or shoulder, so that inadvertent traction on the tube does not dislodge it.
    • Radiographic confirmation of the placement is not necessary if suction is to be applied.
      • The tube may be used for decompression immediately. NG tubes have radio-opaque marker tape incorporated into their design so they are visible on routine abdominal x-ray.
    • You may want to place a mark on the tube near the nose, to mark proper placement.
  • Document the procedure.
  • Routine care
    • Record suction output volume and character.
      • If the output is of a large volume, consider replacement of NG output.
    • If the tube becomes blocked, attempt to irrigate it with 30 to 40 mL of NS.
    • If routine x-rays are taken for other reasons, examine them for appropriate placement of the NG tube.
  • An indwelling NG tube often is very uncomfortable.
    • Make sure the patient has some throat lozenges at the bedside for PRN use.


  • Trauma to nasal mucosa or nares skin
  • Trauma to lung or esophagus
  • Trauma to the gastric mucosa
  • Sinusitis
  • Aspiration pneumonia
  • Nonfunctional or blocked tube. Various techniques are useful to unclog NG tubes.
  • Dislodged tube
    • A tube that is placed too low (i.e., past the pylorus) will drain large volumes of bile.
    • A tube that is placed too high (i.e., in the esophagus) will not adequately drain the stomach and increases the risk of aspiration.


  • Confirm that the tube is no longer necessary.
  • Wear gloves and eyewear to protect yourself from exposure to secretions.
  • Remove the tube from suction.
  • Remove the securing tape from the patient.
  • Hand the patient a tissue because he or she will want to blow their nose.
  • Remove the tube with a steady pressure.
  • Discard in appropriate receptacle.