Nasogastric tube or NG tube in shorten form, is a tube inserted through a nostril into the stomach. The passage will provide many advantages in certain kinds of disease entities. The uses can very from decompressing the stomach, obtaining a sample of the gastric content, provide a passage to the intestinal tract in instances where swallowing becomes difficult or to drain the content of the stomach.
Problems associated with NG tube insertion:
The use of a NG tube is contraindicated at times of facial trauma in which the tube can enter into a passage through a disrupted ‘cribriform plate’. Similarly, unless universal precautions are practiced, the insertion of the NG tube can give rise to many other complications apart from the tissue trauma and vomiting that can be seen in certain patients.
How to insert the tube?
When preparing to insert an NG tube, the clinician must make sure that the indications are met and universal precautions such as hand washing, wearing sterile gloves and masks…etc are met.
The first thing would be to explain the procedure to the patient and mention the indication as to why it is inserted. If the patient is unable to give consent, a legal guardian needs to be informed and the consent obtained.
Measuring the length:
The next step is to measure the adequate length for the NG tube. This can be done using measuring the length between the bridge of the nose to the ear lobe and from their to a place halfway between end of sternum and the naval. The measured length can be marked on the NG tube using a felt tip.
When positioning the patient, it’s best to position him or her upright, which will make the neck and the stomach align better.
Before introducing the NG tube, apply xylocaine gel generously to the proximal part of the tube and sometimes to the nostril as well.
Select the nostril that you want to insert the NG tube and gently introduce the tube into it. As it encounters resistance gentle resistance should be applied with slight rotation, but at no time should be forced.
When the tube reaches the pharynx, ask the patient to swallow or give a sip of water to drink. The swallowing movement will make sure the tube goes into the esophagus rather than in to the airways.
Be aware that, if the patient develops cough, difficulty in breathing as well as changes in color, take the NG tube out immediately.
Following reaching the previously measured distance, attach a suction syringe to the distal end of the NG tube and aspirate the gastric content and should be measured for pH value. The presence of a pH of less than 6.0 would confirm the NG tube present in the stomach.
Following insertion, fix the tube at the entrance of the nose using tape and probably at another site in the face.
Make sure that, when giving a feed to a patient using an NG tube, the position of the tube should always be checked as pulling of the NG tube from its original location is quite common.