Nasogastric (NG) Tube Insertion

Nasogastric (NG) tube insertion is a crucial skill in medical practice, widely utilized across various clinical settings.¹ This procedure involves the placement of a flexible tube through the nasal passage into the stomach, serving multiple purposes in patient care. The video above aims to provide a detailed overview of NG tube insertion, including its indications, contraindications, necessary materials, and the step-by-step process of placement.

The primary indications for NG tube insertion include decompression of the gastrointestinal tract, gastric lavage, nutritional support, medication administration, aspiration of gastric contents, and diagnostic purposes.²

Decompression of the gastrointestinal tract is often required to relieve pressure and prevent vomiting in patients with bowel obstruction, ileus, or severe vomiting.³ This is particularly essential in conditions such as small bowel obstruction, where relieving pressure can prevent perforation and other complications.⁴

Gastric lavage is another important indication for NG tube use, particularly in cases of toxic ingestion, gastric outlet obstruction, and GI bleeding. In gastric outlet obstruction, an NG tube helps decompress the stomach by removing accumulated gastric contents, relieving symptoms. It also facilitates the rapid removal of ingested toxins from the stomach, which is critical in acute poisoning cases.⁵ Additionally, gastric lavage is commonly used to help differentiate upper GI bleeding from lower GI bleeding as the cause of hematochezia or melena.

In terms of nutritional support, NG tubes provide a route for enteral feeding in patients who are unable to take oral nutrition due to conditions such as stroke, head injury, or severe dysphagia. This serves as a temporary solution for nutritional support until the patient can resume normal eating.⁶

NG tubes are also used for medication administration in patients who cannot swallow pills or liquid medications. This is particularly useful for critically ill patients who are intubated or have impaired consciousness. Additionally, in patients at risk for aspiration, such as those with impaired swallowing or decreased levels of consciousness, NG tubes can be used to aspirate gastric contents and prevent aspiration pneumonia.⁷

For diagnostic purposes, NG tubes can be used to obtain gastric contents for analysis, such as in the diagnosis of gastrointestinal bleeding or to measure gastric pH.⁸

Despite their utility, there are several contraindications to NG tube insertion that must be carefully considered to avoid complications. One major contraindication is the presence of a basilar skull fracture. Inserting an NG tube in patients with this condition can lead to intracranial placement of the tube, posing a significant risk of brain injury. Severe facial trauma also poses a contraindication, as it can alter the anatomy and increase the risk of incorrect placement or further injury during insertion.⁹

Patients with esophageal varices or strictures are at high risk for bleeding or perforation during NG tube insertion, making this another relative contraindication.¹⁰ Recent nasal surgery is another contraindication, as the insertion of an NG tube can complicate healing, potentially leading to bleeding or disruption of surgical repairs.¹¹ Furthermore, patients with significant coagulation disorders are at an increased risk for bleeding complications with NG tube insertion, necessitating careful consideration before proceeding.

The following materials are necessary for NG tube insertion:¹²

• Bucket (for potential emesis)
• Suction tubing
• Gloves
• NG tube (18 French recommended for decompression)
• Cup of water with a straw
• Lubricating jelly
• Adhesive bandage
• Tape

The NG tube insertion procedure involves several steps. Before initiating the NG tube insertion procedure, it is crucial to thoroughly explain the process to the patient and obtain informed consent. This step is not merely a legal requirement but an essential aspect of patient-centered care. The healthcare provider should use clear, non-technical language to describe the purpose of the NG tube, the insertion process, potential discomforts, and possible complications. Patients should be encouraged to ask questions and voice any concerns. It's important to explain that while the procedure may cause temporary discomfort, there are ways to minimize this, such as the use of lubricating gel and proper positioning. The patient should be informed about what sensations to expect during the insertion, such as a feeling of pressure in the nasal passage and throat, and the possibility of gagging. Additionally, the healthcare provider should explain how the patient can assist in the procedure, such as by swallowing water when instructed. This comprehensive explanation not only fulfills ethical and legal obligations but also helps to reduce patient anxiety, improve cooperation, and ultimately contribute to a more successful and less traumatic insertion process.

The patient should be positioned in a semi-upright or high Fowler's position, with the head of the bed elevated to approximately 30–45 degrees. This positioning involves raising the entire upper body, not just the head. The patient's back should be supported by the raised bed or pillows. This semi-sitting position helps to reduce the risk of aspiration and makes it easier for the patient to swallow during the procedure.
The patient’s head should be positioned either in a neutral alignment or slightly flexed forward, as both approaches are effective and depend on clinical preference and patient comfort. A small pillow may be placed behind the neck to maintain a neutral cervical spine alignment, which facilitates the natural curvature of the nasopharynx and oropharynx, aiding the passage of the NG tube.

Alternatively, the patient may sit upright with their chin slightly tucked toward their chest during tube insertion. This position helps close off the trachea and open the esophagus, further reducing the risk of inadvertent tracheal intubation. Either technique can be used effectively based on the specific circumstances of the procedure.

It's important to ensure that the patient is as comfortable as possible in this position, as comfort can contribute to better cooperation and ease of insertion. The healthcare provider should also position themselves at a comfortable height relative to the patient, often standing to the side of the bed, to allow for smooth insertion of the tube.

The length of the tube to be inserted is then measured from the tip of the nose to the earlobe, and then to the xiphoid process. Most NG tubes have markings at 50, 60, and 70 cm from the tip for accurate placement. The distal end of the tube is lubricated with water-soluble jelly. The tube is then gently inserted through the nares and advanced as the patient swallows sips of water. The tube is advanced until the predetermined mark is reached. Proper placement is confirmed by auscultating the epigastrium during air injection, aspirating gastric contents, or using radiographic verification. Finally, the tube is secured to the patient's nose using the adhesive bandage and to the patient's gown using tape and a safety pin.^13–15

After successful NG tube insertion, proper care and monitoring are essential for patient safety and effective treatment. Immediately following insertion, tube placement should be confirmed via radiographic verification.¹⁶ The tube must be securely fastened to prevent displacement, and the patient should be assessed for any immediate complications such as bleeding or respiratory distress. Regular assessments are crucial, including daily checks of the insertion site for irritation or infection, verification of tube position at least once per shift, and evaluation of patient comfort. Tube maintenance involves flushing with 30–50 mL of water every 4–6 hours during continuous feeds or before and after intermittent feeds and medication administration. Oral hygiene and nasal care are important to prevent infections and maintain skin integrity. During feeding, patients should be monitored for signs of intolerance such as nausea or abdominal distension, and the head of the bed should be elevated to reduce aspiration risk. Healthcare providers must remain vigilant for potential complications like aspiration pneumonia, tube displacement, or sinusitis. Patient and family education about tube care and warning signs is crucial, especially if the patient will be discharged with the NG tube in place. Accurate documentation of all assessments, interventions, and complications is essential.

While the basic principles of NG tube insertion remain consistent, certain patient populations require special considerations. In children, the size of the NG tube must be carefully selected based on the child's age and size. Typically, smaller French sizes are used. The insertion depth is also different; in neonates and infants, the distance from the nose to the earlobe to the midpoint between the xiphoid process and umbilicus is used.¹⁷ Parental presence and comfort measures are crucial. In some cases, mild sedation may be considered, though this should be done with caution and under close monitoring.^18–20

Older adults may have anatomical changes that make NG tube insertion more challenging. These can include nasal septum deviation, decreased gag reflex, or cervical spine arthritis limiting neck movement. Extra care should be taken to prevent trauma, and a smaller tube size may be preferable. Cognitive impairments may necessitate additional explanation and reassurance throughout the procedure.²¹

For patients who are intubated or unconscious, the swallowing technique cannot be used to aid insertion. In these cases, gentle advancement of the tube with concurrent neck flexion can help guide the tube into the esophagus. Extra caution must be taken to verify correct placement, often requiring radiographic confirmation.^22,23

Individuals with a history of head and neck surgery, radiation therapy, or anatomical abnormalities may require modified insertion techniques. In some cases, endoscopic guidance may be necessary for safe insertion.

While severe coagulopathy is a relative contraindication, in cases where NG tube insertion is necessary, extra precautions should be taken. This may include correcting the coagulopathy if possible, using a smaller tube size, and having measures ready to manage potential bleeding.

This comprehensive guide to NG tube insertion is important for medical practitioners, particularly those in surgical and critical care settings. The video serves as a valuable educational resource for medical students, residents, and practicing clinicians who may need to perform this procedure. Providing a clear, detailed explanation of the procedure helps ensure that healthcare providers can perform NG tube insertion safely and effectively, minimizing risks to patients. This guide is particularly beneficial for medical students learning about basic clinical procedures, surgical and emergency medicine residents honing their skills, nurses who may be involved in NG tube care and management, and practicing physicians who need a refresher on the procedure. By emphasizing patient safety, proper technique, and the importance of understanding both indications and contraindications, this guide contributes to improved patient care and outcomes in clinical settings where NG tube insertion is frequently performed.