Verifiying gastric tube placement using neck ultrasonography in mechanically ventilated patients in the intensive care unit

Abstract

Aims: This study aimed to compare neck ultrasonography to chest X-ray—the gold standard technique—to evaluate the effectiveness in verifying gastric tube placement. Methods: This prospective study reported the data of the 39 mechanically ventilated patients in the intensive care unit. While inserting the gastric tube, a linear ultrasound probe was simultaneously used to visualize the esophagus in the left lateral region of the neck, and obscuration of the posterior esophageal wall was observed during passage of the tube. In addition, ultrasonography was used to detect “dynamic fogging” in the stomach, while auscultation was also used to determine the location of the tube. Chest X-ray images were captured from all patients included in the study. Results: Among 39 patients who had been enrolled in the study, three of them died before chest X-ray, the esophagus could not be visualized in 9 and the stomach could not be visualized in 4 using ultrasonography. The sensitivity, specificity, positive predictive value, negative predictive value of neck ultrasonography in verifying gastric tube placement were 69.7%, 66.7%, 95.8% and 16.7%, respectively and, 51.5%, 100%, 100% and 15.7%, respectively, for stomach ultrasonography. Conclusion: Visualization of gastric tube insertion in the esophagus using neck ultrasonography demonstrated various advantages including non-invasiveness, rapidity, and bedside technique availability, although it has lower sensitivity and specificity due to its operator-dependent nature.