What is a nasogastric tube?
A nasogastric (NG) tube is a fine hollow tube inserted through the nostril into the stomach. A port on the end outside of the body is used to fit onto syringes or tubes which can be used for feeding, administering medications and draining stomach contents.
What is a nasogastric tube used for?
An NG tube is used to administer nutrition, hydration, and medication – it is a way to get substances into the stomach when it isn’t possible or advisable for someone to swallow them by mouth. It can also be used to supplement oral intake when people are having trouble meeting their nutritional needs.
An NG tube can also be used to drain or empty the stomach, which may be needed when someone has swallowed something toxic or because they have some disorder that requires stomach emptying, such as a bowel obstruction.
Who needs a nasogastric tube?
NG tubes are commonly used for feeding people who have a compromised swallowing ability, such as those who’ve had a stroke that’s affected their swallowing reflexes or when they have variable levels of consciousness. They are also used to supplement nutritional intake in people who are unable to meet their nutritional needs through oral intake alone. There are various reasons for this, including poor appetite because of illness or medications.
There are different formulations of NG feed available, and a dietitian or other specialist may recommend a specific one; some are higher or lower in certain nutrients like fibre, protein, or carbohydrates depending on the needs of the individual, but all are fully nutritionally balanced with a mix of vitamins, minerals, and other nutrients.
Some acute illnesses can mean that someone needs to have an NG tube to empty the contents of the stomach. This can be done regularly or as needed with syringes attached to the port, or the NG tube can continuously drain contents into a sealed bag.
What is nasogastric intubation?
Nasogastric intubation is the medical procedure in which an NG tube is inserted. It should only be done by someone who has had training. This can be a healthcare professional or trained caregiver. Sometimes people learn to insert their own NG tubes when they are expected to need them frequently or long-term at home.
NG tubes are soft rubber-like plastic tubes which are moistened with water or water-based lubricant and fed into the nose and down to the stomach. They usually contain a guide wire which makes them slightly stiffer, making them easier to insert. This guide wire is visible on an X-ray. In a hospital setting, the position of the NG tube can be checked on an x-ray before the guide wire is removed. Another way to check that the NG is in the right place is to use a syringe on one of the ports to draw up a small amount of the stomach contents. Stomach bile is very acidic and putting a small amount onto litmus paper to test the pH of the gastric contents will give a good indication that the NGT is indeed in the stomach.
NG tubes can either be held in place by surgical tape on the nose and cheek or a ‘bridle’. A nasal bridle is a clip that ties around the nasal septum via each nostril and clips to the NG tube, holding it securely in place.
How do nasogastric tubes work?
There are one or more ports at the end of a NG tube for access to the stomach. These ports attach to syringes or tubes for giving liquid medications and fluids for nutrition and hydration.
NG feeds are often given by continuous infusion, using a programmable pump to ensure that the amount given can be carefully measured. This can be good for people who can’t tolerate a large amount of anything in the stomach at once. Alternatively, someone may have their feed in the form of a ‘bolus’; this is where a set amount of liquid feed is given in one go, usually several times a day, equivalent to having a meal. This has the benefit of not having to be attached to a machine for long periods, meaning it’s easier to go about your normal activities.
Nasogastric tubes that are used for draining stomach contents are usually only used in acute illness in a hospital setting.
Some NG tubes can stay in place for up to 6 weeks before being changed, as long as they’re carefully looked after and don’t develop any complications.
Types of Nasogastric Tubes
There are different types of NG tube and the type chosen will depend on the reason for having it.
NG tubes used to drain stomach contents, such as Ryles tubes, typically have a wider bore than those only for feeding.
Some NG tubes designed for more complex aspiration of stomach contents have two channels within a single tube. A tube designed solely for feeding can be narrower than those used to aspirate gastric contents.
Some NG tubes can be left in longer than others, so it’s important to know which type you have if it’s going to be a long-term solution.
What are the risks of nasogastric intubation?
Having an NG tube is only recommended where medically indicated, so the benefits will be thought to outweigh the risks. NG tubes are used quite frequently and routinely without any problem, but it’s important that people with NG tubes and their carers or those around them are aware of possible complications. Identifying issues early means that they can be managed before they become a serious problem.
One of the most serious complications that can occur with an NG tube is misplacement or displacement of the tube, which can mean that fluids administered through NG could end up in the lungs and cause pneumonia.
If an NG tube is inserted correctly, has its placement confirmed, and the acidity of the stomach contents are checked before every administration, it is a safe treatment.
On rare occasions, insertion of an NG tube can cause trauma or even perforate the oesophagus or stomach.
Less serious complications may include nosebleeds, discomfort, and sometimes sores in or around the nose. People with bleeding disorders or who take blood thinners such as warfarin are more at risk of problems with bleeding. If it becomes a problem medical advice should be taken.
How do I lower the risk of complications?
Before every feed, it’s important to check the placement of the tube. If the tube has come loose or isn’t in as far as normal, there is a risk that some of the liquids administered through it could be aspirated into the lungs, causing aspiration pneumonia. NG tubes have their lengths marked along them so it’s easy to tell if the tube is not inserted fully. Displacement is more common if you’ve been coughing, vomiting, or retching a lot. A small amount of gastric content should be aspirated into a syringe and the pH checked before every administration.
It’s important to always make sure the environment and equipment are clean, including good hand-washing, whenever anything is going to be given through the tube. Regularly flushing water through the tube also helps to keep it clean and patent.
Knowing what to look out for is important to reduce any risks associated with NG administration, and it’s particularly important to look out for breathing problems.
Some medications come in liquid form, and some can be dispersed or crushed and mixed with water to be given through the NG tube. However, some tablets should NOT be crushed, and some capsules should NOT be opened; a pharmacist or doctor can advise you about the best forms of medication to go through your NGT.
Maintaining Oral & Tube Hygiene
Some people with NG tubes can also eat and drink normally. These individuals should follow good normal oral hygiene; brushing teeth and staying hydrated. Other people may be unable to take anything by mouth so the mouth can become parched and sore. Good mouth care can help to prevent problems like mouth ulcers, fissures, and oral thrush; regularly moistening the delicate tissues of the mouth keeps them healthy. Small ‘lollipop’ type sponges made specifically for mouth care are useful for some people as they are designed not to be able to break into pieces or be accidentally swallowed.
NG tubes used for feeding are quite narrow and it is possible for them to become clogged. Flushing them with clean water before and after every feed is important to ensure that the tube doesn’t retain any of the feed, which can thicken and become sticky. Some medications, especially suspensions or dispersible powders, can also cause blockages if they’re not properly flushed. If you take tablets that a pharmacist has told you can be crushed, you can get special tablet crushers to ensure they’re ground to a fine powder and prevent blockages.
NGT Care at Home
Having an NG tube can be a short term solution to an acute illness or a longer-term solution for ongoing needs. Some people learn to care for their NGT, check its position and deliver medications and feed completely independently, but for most, it’s easier with an extra pair of hands. Having trained caregivers or nurses who can come in and assist with NG care can enable you to remain as independent as possible with these additional needs.
- Quilliot, D., Zallot, C., Malgras, A., Germain, A., Bresler, L., Ayav, A., … & Ziegler, O. (2014). Self‐insertion of a nasogastric tube for home enteral nutrition: a pilot study. Journal of Parenteral and Enteral Nutrition, 38(7), 895-900. https://doi.org/10.1177/0148607113502544
- Ni MZ, Huddy JR, Priest OH, et al (2017) Selecting pH cut-offs for the safe verification of nasogastric feeding tube placement: a decision analytical modelling approach BMJ Open https://bmjopen.bmj.com/content/7/11/e018128
- Thomas DR (2020) Enteral tube nutrition. Merck Manuals . https://www.msdmanuals.com/en-gb/professional/nutritional-disorders/nutritional-support/enteral-tube-nutrition
- Blumenstein, I., Shastri, Y. M., & Stein, J. (2014). Gastroenteric tube feeding: techniques, problems and solutions. World Journal of Gastroenterology: WJG, 20(26), 8505. https://dx.doi.org/10.3748%2Fwjg.v20.i26.8505
- Jain Bhaskara Pillai, Annette Vegas, Stephanie Brister (2005) Thoracic complications of nasogastric tube: review of safe practice, Interactive CardioVascular and Thoracic Surgery https://doi.org/10.1510/icvts.2005.109488