Nasogastric tube positioning

Assessment of nasogastric (NG) tube positioning is a key competency of all doctors as unidentified malpositioning may have dire consequences, including death.

The ideal position should be in the sub-diaphragmatic position in the stomach - identified on a plain chest radiograph as overlying the gastric bubble. Ideally, it should be at least 10 cm beyond the gastro-esophageal junction ¹.

Malpositioning may include tip position:

• remaining in the esophagus
• traversing either bronchus or more distally into the lung
• coiled in the upper airway
• intracranial insertion, possible in both patients with and without maxillofacial trauma or surgery ²

In some circumstances fluoroscopic nasojejunal tube insertion is necessary.

Ultrasound

Point-of-care ultrasonography may be utilized to guide the nasogastric tube in real time with the probe placed sequentially in the following locations ⁷;

• anterolateral neck
  • cervical esophagus typically visualized to the left, posterolateral to the trachea
  • an intraluminal curvilinear echogenic interface represents esophageal placement of the tube
• epigastrium
  • with a longitudinal view of the gastroesophageal junction, the nasogastric tube may be advanced into the stomach under direct visualization
  • oblique and sagittal scan planes to view the tube coursing through the gastric fundus and terminating in the antrum, confirming correct placement

Complications

Overall, complications occur in 1-2% of cases, with complications leading to death occurring in approximately 0.3% of cases. Complications include ^1-6: 

• upper airway
  • epistaxis from insertion trauma
• lower airway
  • aspiration pneumonia
  • pneumothorax
  • hemorrhage
  • empyema
• enteral
  • viscus perforation and mediastinitis or peritonitis
    • may further complicate with intravascular placement
  • viscus obstruction
  • knotting/tangling of the tube
  • intramural esophageal dissection
• intracranial
  • meningitis