Chapter 35: Gastric and Postpyloric Tube Placement

INTRODUCTION

Gastric tube placement involves placing a tube through the nose (nasogastric [NG]) or mouth (orogastric [OG]) into the stomach. In a postpyloric (sometimes referred to as transpyloric) tube placement, a tube is inserted through the nose or mouth through the pylorus into the small bowel (duodenum or jejunum).

GASTRIC TUBE PLACEMENT

I. INDICATIONS

1. To perform enteric feeding in the following situations:

   1. High respiratory rate. Enteric feedings are used at some centers if the respiratory rate is >60 breaths/min to reduce the risk of aspiration pneumonia (controversial).

   2. Nutritional support in premature infants who may have immature sucking and swallow mechanisms that normally develop after 32 weeks.

   3. Neurologic disease that impairs the sucking reflex or the infant’s ability to feed. An abnormal gag reflex is also an indication for a gastric tube.

   4. Insufficient oral intake.

2. Gastric decompression in infants with necrotizing enterocolitis (NEC), bowel obstruction, congenital diaphragmatic hernia, intestinal malformations, or ileus.

3. Administration of medications. Consult a pharmacist for medications that are administered into the stomach.

4. When a postpyloric tube is placed, a gastric tube is needed to empty gastric contents and administer medications.

5. Analysis of gastric contents.

II. EQUIPMENT

Infant feeding single-lumen tube (3.5 or 5F if <1000 g or 5–8F if ≥1000 g), dual-lumen vented Replogle tube for decompression (6, 8, or 10F; Note: tubes come with and without stylets; stylet use is not recommended in neonatal population), stethoscope, sterile water (to lubricate the tube), syringes (10–20 mL), 1/2-inch adhesive tape, benzoin, gloves, suctioning equipment, cardiac monitor, pulse oximeter, stethoscope, pH paper, and bag-and-mask ventilation with 100% oxygen (in case of emergency). Strongly recommended is a colorimetric device (eg, Kangaroo CO₂ Detector; Covidien, Mansfield, MA) or capnograph to help confirm the position of the tube by absence of carbon dioxide (CO₂) within the tube.

III. PROCEDURE

1. Monitor heart rate and respiratory function throughout the procedure. Place the infant in the supine position, with the head of the bed elevated. The infant can be swaddled to provide comfort.

2. There are several methods of estimating gastric tube insertion length:

   1. Orogastric tube insertion in very low birthweight infants. Table 35–1 provides OG guidelines for infants <1500 g.

   2. NEX method. This method measures from the nose to the ear to the xiphoid (NEX) process. This method has been used for years but may misplace tubes, usually in the esophagus (up to 21%). This method is no longer recommended.

   3. Age-related/height-based method. In the age-related/height-based (ARHB) method, heights in age groups are used; this method requires multiple calculations that are time consuming and may lead to errors.

      1. Less than 1 month of age: nasogastric only

         1. Nasogastric tube insertion length (cm) = 1.950 cm + 0.372 × (infant’s length in centimeters)

      2. Greater than 1 month of age (if >44.5 cm in ...