Insertion of Nasogastric Tube

Subject: Nasogastric Tubes
Area: Drainage Systems. Nutrition
Classification: Clinical Practice
Relevant to: All Clinical Staff
Implementation Date: March 2001
Review Date: March 2004
Responsible for Review: Clinical Practice Committee
Approved by: Executive Director
Distribution: All Clinical Units
Location: Clinical Practice Manual


1.1 The nasogastric (N/G) tube will be inserted according to the principles of:

Clean technique
Patient consent
Patient privacy
Patient comfort and safety
Standard Precautions


2.1 Equipment Required
2.1.1 N/G tube (Appropriate type and size, see CP/Pol/N2, point 7.0)
2.1.2 50ml catheter tip syringe
2.1.3 Universal pH indicator strips
2.1.4 Stethoscope
2.1.5 Non-sterile gloves and protective faceshield
2.1.6 Water soluble lubricant (sterile lubricating jelly)
2.1.7 Kidney dish
2.1.8 Blue incontinent sheet
2.1.9 Non-stretch tape or transparent dressing, e.g. leukoplast™
2.1.10 Scissors
2.1.11 Yankeur sucker connected to high suction outlet
2.1.12 Anti-reflux valve or drainage bag as required
2.1.13 Sips of water to facilitate swallowing and to lubricate the oropharynx.
N.B.This is only appropriate if the patient is fully conscious, co-operative and
has an intact gag reflex and swallowing skills.

2.2 Equipment Preparation

2.2.1 Prepare equipment on a clean dressing trolley.
2.3 Procedure
2.3.1 Establish a hand signal for the patient to use should they feel that they are unable to continue with the procedure.
2.3.2 Position the patient in a high sitting position, unless contraindicated.
2.3.3 Approximate the length of N/G tube to be inserted. Measure the combined distance from the ear lobe to the tip of the nose and the nose to the lower end of the xyphoid process.
2.3.4 Mark the measured distance (point 2.3.3) on the N/G tube by placing a sticker (tape) on the tube at this point. Upon N/G tube insertion, the N/G tube is to exit the nose at the position of the sticker (tape).
2.3.5 Don protective faceshield and gloves.
2.3.6 Place blue incontinent sheet and kidney dish under the patient’s chin. Ensure suction is available.
2.3.7 Lubricate the end of the N/G tube, approximately 7.5-10cm (Potter and Perry, 1997). Avoid occluding the holes of the N/G tube with lubricant.
2.3.8 Unless contraindicated, ask the patient to flex their neck slightly and insert. Prior to the procedure determine the specific indication for N/G tube insertion. If the N/G tube is required because the patient's gag reflex is absent,
it is imperative that the patient is NOT given any sips of water/ice to suck during the procedure. Insert the N/G tube through the nostril. Aim the N/G tube downward along the floor of the nose. Flexing the neck slightly helps close the trachea and open the oesophagus. Mild intermittent resistance may be met. Under no circumstances is excessive force to be used whilst inserting the N/G tube.
2.3.9 Once the N/G tube has passed the initial resistance (posterior wall of the nasopharynx) and has reached the oropharynx, instruct the patient to initiate swallowing on N/G tube advancement. Swallowing closes the trachea and facilitates the N/G tube’s passage into the oesophagus. Only if the patient is fully conscious, co-operative and has an intact gag reflex and swallowing
skills, may sips of water/ice be offered to the patient to facilitate swallowing.
2.3.10 Insert N/G tube until the sticker/tape (point 2.3.4) is at the level of the nostril.
2.3.11 If the patient experiences gagging, choking, coughing or difficulty breathing, the procedure is to be aborted. Resume insertion attempt when the patient is ready. After three (3) unsuccessful attempts refer to a more senior nurse or MO.
2.3.12 Ensure that the nose and N/G tube are clean and dry before securing the tube.
2.3.13 Clearly mark the exit site of N/G tube at nose using tape as per CP/Pol/N2, point 9.0.
2.3.14 Verify N/G tube position as per point 2.4.
2.3.15 If inserting a size 8Fg polyurethane feeding tube, remove and discard the stylet. The stylet is not to be re-used.
2.3.16 Either place an anti-reflux valve on the end of the N/G tube or connect the N/G tube to a drainage bag or to low suction, as per CP/Pol/N2, point 12.0.

2.4 N/G Tube Position Verification

2.4.1 Ask the patient to open his/her mouth. Inspect the oropharangeal cavity for a recoiled or malpositioned N/G tube.
2.4.2 Two (2) people, either 2 RNs or an RN and a MO, are to assess N/G tube position using one or both of the following methods, and/or, followed by an xray where indicated (Refer 2.4.3 and 2.4.4). The method/s selected is/are to be at the discretion of the 2 people and in accordance with the following:
• If the patient is receiving enteral feeding and/or antacid/acid inhibitor therapy the auscultation method is to be used. The
aspiration method is NOT to be used because the result will be unreliable. Aspiration Method

Aspirate the N/G tube and check the pH of the aspirate with a universal pH indicator strip. The pH of gastric contents should be less than (five) 5 (Sleisenger & Fordtran, 1993). If the pH is less than 5, the N/G tube is most likely to be in the correct position, with the following exceptions. pH measurement of gastric contents is unreliable if:
• the patient is receiving enteral feeding via a N/G tube. This is due
to the presence of the feeding formula itself.
• the patient is receiving antacid or acid inhibitor therapy, e.g.
cimetidine (tagametĀ®), ranitidine (zantacĀ®). Auscultation Method

Simultaneously introduce 10-20mls of air into the N/G tube using a syringe while listening with a stethoscope over the left upper quadrant of the abdomen. A loud “whooshing” or “gurgling” sound will be heard if the N/G tube is correctly positioned. The 2 people are required to auscultate with a stethoscope to verify location of sounds.
2.4.3 If the 2 people can not confirm the position of the N/G tube as per 2.4.2, the MO is to be notified. If there is doubt as to N/G tube position, the MO is to order an xray.

2.4.4 If the N/G tube is to be used for enteral feeding, an xray must be attended and N/G tube position on xray must be verified by a MO before feeding is commenced (CP/Pol/N2, point 8.3). The tube position is to be assessed as per 2.4.2 prior to xray attendance.
2.4.5 If any assessment of N/G tube position (e.g. aspiration method, auscultation method, xray) indicates incorrect positioning, remove and reinsert the N/G tube.
2.4.6 The number of N/G tube insertion attempts is to be limited to a maximum of 3 attempts. After 3 unsuccessful attempts, or earlier if the patient is experiencing complications (Refer 2.3.11), refer to a more senior nurse or MO.
2.5 Disposal of Equipment
2.5.1 Dispose of equipment appropriately.


3.1 The MO is to write a request for N/G tube insertion in the Medical Record.
3.2 The MO/RN who inserts the N/G tube is to document the N/G tube type and size, the nostril (left or right) the N/G tube is in, any insertion events and N/G tube position verification in the Medical Record.
3.3 Where applicable, the MO is to document radiological verification of N/G tube position in the Medical Record.


  • St Vincent’s Hospital Sydney. (2001), Clinical Practice Manual:Enteral Nutrition via a Nasogastric Tube, CP/Pol/N2.2
  • Nasogastric Tube Management, CP/Pol/N2
  • Nasogastric Tube Removal, CP/Proc/N2.3
  • St. Vincent’s Hospital Sydney. (2000), Policy and Procedure Manual, Informed Consent, Section 1, Policy 3.


  • Loan, T., Magnusun, B. & Williams, S. (1998), Debunking Six Myths about Enteral Feeding, Nursing 98, 28(8): 43-49
    NSW Health Dept. (1999), Standard Precautions Infection Control Policy 99/87
  • Penrod, J.; Morse, J.M. and Wilson, S. (1999), Comforting Strategies used during Nasogastric Tube Insertion, Journal of Clinical Nursing, 8 : 31-38
  • Potter, P.A. and Perry, A.G. (1997), Fundamentals of Nursing. Concepts, Process and Practice, Mosby, Sydney
  • Sleisenger, M.H. & Fordtran, O.S. (1993), Gastrointestinal Diseases Pathophysiology, Diagnosis, Management, (5th Edition), Saunders,


  • Clinical Nurse Consultant Nutritional Support, Intravenous Therapy and Acute Pain Management, St Vincent's Hospital Sydney
  • Head Gastroenterology Clinical Service Unit, St Vincent's Hospital Sydney
downloading icon illustration of a printer
Page updated 24-Feb-07