Comparison of neck ultrasonography with a pH meter to confirm correct position of nasogastric tube

Abstract

Purpose: The aim of this study was to compare pH meter and neck ultrasonograph forevaluation of nasogastric tube (NGT) position.Methods: A total of 35 adult patients who required NGT insertion were included. TheNGT was inserted by an anesthetist after endotracheal intubation, and the transducer wasplaced transversely on the neck, just superior to the suprasternal notch. The passage of theNGT in the esophagus was evaluated by a sonographer, and the stomach was emptied bynasogastric suction. Secretion from inside the NGT was analyzed using a pH meter. Thetip of the NGT was accepted as being in the stomach if the pH measured between 1 and 5.Neck ultrasonography was compared with the pH meter analysis for confirmation ofNGT position.Results: Ultrasonography was highly sensitive (100% (95% CI 89.6–100%) and specific(97.2% (95% CI 85.4–99.5%) for evaluation of NGT position. The specificity for the pHmeter was 100% (95% CI 16.6–100%), while the sensitivity was 76.5% (95% CI 58.8–89.2%).Conclusions: This study showed that neck ultrasonography is more sensitive than the pHmeter for confirmation of NGT position.