NASOGASTRIC TUBE INSERTIONFOR PEDIATRIC PATIENTS

Dr. Michael Jude D. Medalla, M.D

Background

• Gastric intubation via the nasal passage (ie, nasogastric route) is a common procedure that provides access to the stomach for diagnostic and therapeutic purposes. A nasogastric (NG) tube is used for the procedure. The placement of an NG tube can be uncomfortable for the patient if the patient is not adequately prepared with anesthesia to the nasal passages and specific instructions on how to cooperate with the operator during the procedure

Indications

Diagnostic indications for NG intubation include the following:• Evaluation of upper gastrointestinal (GI)

bleeding (ie, presence, volume)• Aspiration of gastric fluid content• Identification of the esophagus and stomach on

a chest radiograph• Administration of radiographic contrast to the

GI tract

IndicationsTherapeutic indications for NG intubation include the following:

• Gastric decompression, including maintenance of a decompressed state after endotracheal intubation often via the oropharynx

• Relief of symptoms and bowel rest in the setting of small-bowel obstruction

• Aspiration of gastric content from recent ingestion of toxic material• Administration of medication• Feeding• Bowel irrigation• NG tube can be kept following corrosive ingestion for the development

of a tract in the esophagus that subsequently can be used for balloon dilatation

Contraindications

Absolute contraindications for NG intubation include the following:• Severe midface trauma• Recent nasal surgery

Relative contraindications for NG intubation include the following:• Coagulation abnormality• Esophageal varices or stricture• Recent banding of esophageal varices• Alkaline ingestion

Equipment• NG tube (for adult patients) - 16-18 French• NG tube (for pediatric patients) - In pediatric patients, the correct tube size varies

with the patient's age; to find the correct size (in French), add 16 to the patient's age in years and then divide by 2, so that for an 8-year-old child, for example, the correct size is 12 French ([8 + 16]/2 = 12)

• Viscous lidocaine 2%• Oral analgesic spray (benzocaine spray or other)• Syringe, 10 mL• Glass of water with a straw• Water-based lubricant• Toomey syringe, 60 mL• Tape• Emesis basin or plastic bag• Wall suction, set to low intermittent suction• Suction tubing and container

Equipment

Patient PreparationAnesthesia• Various methods of topical anesthesia for nasogastric (NG) intubation have been

proven effective in pain relief and improve the likelihood of successful NG intubation.• The use of viscous lidocaine (ie, the sniff and swallow method) was found to

significantly reduce the pain and gagging sensation associated with NG tube insertion.

Viscous lidocaine is discussed in more detail in the Technique section below.• Alternative techniques include the following:• Nebulization of lidocaine 1% or 4% through a face mask (≤4 mg/kg; not to exceed 200

mg per dose in adults) is an option; the authors recommend that a preservative-free lidocaine (ie, intravenous lidocaine) be used for nebulization in order to minimize the risk of allergic reaction

• An anesthetic spray that contains benzocaine or a tetracaine/benzocaine/butyl aminobenzoate combination may be applied to the nasal and oropharyngeal mucosa; be advised that incidents of methemoglobinemia after a single use of benzocaine topical sprays have been reported to the US Food and Drug Administration (FDA)

Patient Preparation

Positioning• The patient should be seated in an upright

position.

Placement of nasogastric tube

• Explain the procedure of nasogastric (NG) intubation, as well as its benefits, risks, complications, and alternatives, to the patient or the patient's representative.

• Examine the patient's nostril for septal deviation. To determine which nostril is more patent, ask the patient to occlude each nostril and breathe through the other.

• Instill 10 mL of viscous lidocaine 2% (for oral use) down the more patent nostril with the head tilted backwards (see the images below), and ask the patient to sniff and swallow to anesthetize the nasal and oropharyngeal mucosa. In pediatric patients, do not exceed 4 mg/kg of lidocaine. Wait 5-10 minutes to ensure adequate anesthetic effect.

Placement of nasogastric tube

• Estimate the length of insertion by measuring the distance from the tip of the nose, around the ear, and down to just below the left costal margin. This point can be marked with a piece of tape on the tube.

Placement of nasogastric tube

• Position the patient sitting upright with the neck partially flexed. Ask the patient to hold the cup of water in his or her hand and put the straw in his or her mouth. Lubricate the distal tip of the NG tube

Placement of nasogastric tube

• Gently insert the NG tube along the floor of the nose, and advance it parallel to the nasal floor (ie, directly perpendicular to the patient's head, not angled up into the nose) until it reaches the back of the nasopharynx, where resistance will be met (10-20 cm).

• At this time, ask the patient to sip on the water through the straw and start to swallow. Continue to advance the NG tube until the distance of the previously estimated length is reached

Placement of nasogastric tube

• Stop advancing the tube and completely withdraw it if, at any time, the patient experiences respiratory distress, is unable to speak, has significant nasal hemorrhage, or if the tube meets significant resistance.

• Verify proper placement of the NG tube by auscultating a rush of air (2-3 cc) over the stomach using the 60 mL Toomey syringe or by aspirating gastric content. The authors recommend always obtaining a chest radiograph in order to verify correct placement, especially if the NG tube is to be used for medication or food administration.

Placement of nasogastric tube

• Apply benzoin or another skin preparation solution to the nose bridge. Tape the NG tube to the nose to secure it in place. If clinically indicated, attach the tube to wall suction after verification of correct placement.

Complications

• Some degree of patient discomfort is common. Generous lubrication, the use of topical anesthetic, and a gentle technique may reduce the patient’s level of discomfort. Throat irritation may be reduced with administration of anesthetic lozenges (eg, benzocaine lozenges) prior to the procedure.

• Epistaxis may be prevented by generously lubricating the tube tip and using a gentle technique. Other complications that may occur are respiratory tree intubation and esophageal perforation.