An NG tube, or nasogastric tube, is a thin plastic tube that can be inserted into the stomach to drain fluids and provide nutrition for patients who are unable to eat on their own. This is an important procedure, and having the right size tube is a critical part of the process.
We took a closer look at the significance of NG tubes, as well as the best way to measure for one to ensure that patients receive the highest levels of care.
What Is An NG Tube?
An NG tube is a thin plastic tube with a bulb-like end that is inserted into your patient’s nose or mouth. It can also be used in other parts of the body, such as the bladder or intestines.
One purpose of this tube is to remove fluid from the stomach, which may have been caused by vomiting or diarrhea.
NG tubes may also be used to provide nutrition to patients who cannot take food orally. They can be placed through the nose or mouth, depending on where they need to go.
The tube is usually composed of soft plastic, which will be approved for medical use, and designed to be as comfortable as possible for the patient while the NG tube is in place.
NG Tube Sizes
NG tubes are measured and categorized according to the diameter of the tube, and the length of the tube, known as the French gauge (Fr), or the Charrière scale (Ch). The larger the Fr number, the wider the diameter of the tube will be.
As a rule, neonates will usually have an NG tube of 3.5Fr, while most adults will be fitted with a 14 Fr tube – this can reach up to 24 Fr for triple-lumen gastric feeding or drainage tubes.
The smaller the tube – under 12 Fr – the higher the levels of patient comfort, and the smaller the risk of any tube feeding complications. Healthcare professionals should therefore opt for a small-bore tube wherever possible.
Generally, tubes between 8 Fr and 12 Fr will be used for feeding purposes, and tubes over 12 Fr will be used for drainage purposes – the larger diameter of these tubes means that there are less likely to be clogs and blockages.
How Do I Measure My Patient For An NG Tube?
The first step when measuring your patient for an NG tube is to make sure that they are sitting upright, with their head placed in a neutral position.
Next, measure the distance from the bridge of the nose to the earlobe, and then measure down to 5 cm below the xiphoid process – this will give you the length of the tube required for that particular patient.
What Are The Different Types Of NG Tubes Available?
There are two main types of NG tubes available:
- Double lumen
- Single lumen
A double-lumen tube has two lumens – one for feeding and one for draining. It is commonly used for patients who are unable to eat or drink due to vomiting or diarrhea.
A single-lumen tube has just one lumen – it is usually used for patients who can feed themselves but still need to drain fluids.
Both types of tubes come in different sizes. If you are unsure which size to choose, ask your doctor.
Why Do I Need An NG Tube?
There are many reasons why you might need an NG tube. Some common causes include:
- Vomiting
- Diarrhea
- Constipation
- Head trauma
- Seizures
- Stroke
- Bleeding
- Poisoning
- Intestinal obstruction
- Gastrointestinal bleeding
- Malnutrition
- Drug overdose
- Other medical conditions
If you think that your patient has any kind of blockage in the gastrointestinal tract, they may benefit from an NG tube.
Most people do not require an NG tube for longer than 24 hours. However, you should check your patient every 4 hours while they are receiving treatment. You should also monitor them closely after the tube is removed to check for any complications.
If you notice any signs of dehydration, call your doctor immediately.
How Should I Use An NG Tube?
You should only insert an NG tube under direct supervision by a healthcare provider. Your doctor will determine whether or not an NG tube is required based on your patient’s condition.
Your doctor will give you specific instructions about how to insert the tube. They will tell you what type of needle to use, how long to leave it in place, and how often to check your patient – this will vary from patient to patient, depending on their individual needs and conditions, and it is important to note that each patient will be unique.
The tube is inserted through the nasal cavity, with the direction heading back, and then down. You should then ask your patient to drink a glass of water, and continue to guide the tube with every swallow -this will help to ensure the correct positioning.
Check that the tube is in place by asking your patient to speak, and immediately remove the tube at any signs of respiratory distress, hoarse voice, or mentions of discomfort; this can indicate that the tube is in the trachea, which can cause serious damage.
Once the tube is in place, you will want to keep it in place for no longer than 7 days at a time. After this time, you will need to remove the tube and replace it with another one.
Final Thoughts
An NG tube is a very useful tool for treating some serious illnesses, but getting the measurements correct is crucial for your patient’s well-being and health.
It is important to ensure that you have a good understanding of the steps, and plenty of opportunities to practice measuring for and inserting an NG tube – if you ever have any questions, make sure you ask your mentor or a more experienced practitioner.