Nasogastric intubation is one of the common procedures performed
in Emergency Departments in the United States.1 Its use
as a conduit into the stomach was first popularized in the early
twentieth century mainly through the efforts of Levin. Since then,
clinicians have studied its use and have proposed methods to improve
the ease with which the tube is inserted as well as ways to diminish
the incidence of potentially lethal complications. A nasogastric
tube is often placed in patients who have a bowel obstruction, intractable
nausea and vomiting, intoxication, significant trauma, and upper gastrointestinal
bleeding. The procedure is rapid, simple, and straightforward.
The nasal cavity is lined by the very vascular nasal mucosa.
The medial wall of the nasal cavity is composed of the septum. The
lateral wall of the nasal cavity is covered by the turbinates. The
posterior nasal cavities are continuous with the nasopharynx that
develops into the posterior oropharynx as you move caudally (Figure
47-1). The oropharynx continues inferiorly as the esophagus that
enters the stomach below the diaphragm.2
Basic anatomy of the path of the nasogastric tube.
The placement of a nasogastric tube in children is often difficult.
Their large tonsils and adenoids may hinder the passage of the nasogastric
tube. These tissues are soft, easily injured, and may bleed as the
nasogastric tube is passed. The tongue, large by comparison with
adults, may push into the oropharynx and impede passage of the nasogastric
tube. Their nostrils and nasal passage are quite small and limit
the size of nasogastric tube that may be passed.
Nasogastric intubation may be performed for diagnostic or therapeutic
indications. A nasogastric tube may be inserted to instill air into
the stomach to assess for an intraperitoneal perforation. It is used
to evaluate the presence, rapidity, and volume of an upper gastrointestinal
hemorrhage. Gastric fluid and contents may be aspirated for laboratory
analysis. It may also be placed to visualize the stomach on chest
radiography to assess for a diaphragmatic hernia. A nasogastric
tube is placed in patients for medication administration, relief
of a bowel obstruction, treatment of recurrent vomiting, and to
perform gastric lavage. They are placed preoperatively, postintubation,
prior to a diagnostic peritoneal lavage, or prior to a pericardiocentesis
to decompress the stomach.
Absolute contraindications do not exist for nasogastric tube
placement. The relative contraindications are geared toward predicting
which patients are more likely to experience complications and which
patients are likely to have misplaced tubes. Insertion of a nasogastric
tube should be avoided, unless necessary, in the patient with midface
trauma. Intubation through the nasal cavity can result in the nasogastric
tube being misdirected blindly into the respiratory tract or the
rare perforation through the thin cribriform plate of the ethmoid
bone and into the brain. Patients with facial trauma are best served
with orogastric intubation.3 Patients with esophageal varices
pose potential problems. Placement of a semi-rigid tube into the esophagus
or stomach has the potential to cause rupture of the varices and
uncontrollable hemorrhage. Other relative contraindications include
patients with coagulopathies, esophageal strictures, ingestions
of alkaline substances, nasal obstruction, or recent nasal surgery.
- Topical anesthetic (benzocaine spray, cocaine, viscous
- Topical vasoconstrictor (phenylephrine, oxymetazoline, cocaine)
- Glass of water with straw
- Emesis basin
- Water-based lubricant
- Nasogastric tube
- 60 mL syringe
- Wall suction, set to low intermittent suction
- Suction tubing
- Benzoin spray
- 1 inch adhesive tape
Choose a size of nasogastric tube that is appropriate for the
patient. A size 16 to 18 French is typically used for an adolescent
or adult patient. A formula ([age in years + 16] ÷ 2)
may be used to choose the proper size nasogastric tube for children.
Typical sizes include 8 French for infants, 10 to 12 French
for small children, and 12 to 14 French for older children.
Nasogastric tubes are usually made of clear polypropylene. They
are somewhat rigid and single patient use devices. Typically used
are the Levin tube and the Salem Sump tube. They both have multiple
distal sideports. The Levin tube is a single-lumen tube that is
easy to insert. It is simple to use for the aspiration of gastric
contents, the instillation of fluids and/or medications,
and the application of low intermittent suction. The tube is nonradiopaque.
Unfortunately, the amount of suction is difficult to control with
the Levin tube. The distal sideports often become occluded with the
gastric mucosa, and damage this tissue, when the tube is attached
to suction. The Salem Sump tube is a double-lumen, radiopaque tube.
It has a smaller suction lumen than the Levin tube. The second lumen
allows a constant inward airflow to prevent the sideports from becoming
occluded by the gastric mucosa.
The most beneficial factor in the successful placement of a nasogastric
tube is a patient who is informed of the procedure and can cooperate
with the instructions. Take the patient through each step prior
to the start of the procedure to ensure maximal cooperation. Drape
the patient to protect them and the bedding from soilage if there
is emesis. A glass of water and a straw should be within reach,
as should an emesis basin.
Place the patient seated upright in the Fowler’s or
semi-Fowler’s position. Examine the patient for nasal septal
deviation or other anatomic abnormalities that may hinder the passage
of the nasogastric tube. Ask the patient to breathe through one
nostril while the other nostril is occluded to determine which nostril
is the most patent.4 A recent study suggests that the application
of topical lidocaine and phenylephrine to the nose and benzocaine
spray to the throat resulted in significantly less pain and discomfort
than the use of lubricant alone.5 The patient should be