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Updated: May 10, 2026

Using the Endoscope for Endobronchial Ultrasound in the Esophagus
Published on: November 21, 2023
Utility of unsedated transnasal endoscopy for pharyngeal observation during esophagogastroduodenoscopy. A prospective
Masaru Tsuboi1, Makoto Arai, Daisuke Maruoka
1Department of Gastroenterology and Nephrology, Graduate School of Medicine, Chiba University, Chiba, Japan.
Objectives:
Emergence of image-enhanced endoscopy has enabled an early detection of pharyngeal carcinoma. Pharyngeal observation during esophagogastroduodenoscopy (EGD) is sometimes difficult because of excessive reflexes and is a great burden to the patients and impacts on their cardiopulmonary function. In this study, the authors aimed to evaluate the utility of transnasal EGD (TN-EGD) in comparison with sedated and unsedated transoral EGD (TO-EGD) in pharyngeal observation using a continuous monitoring device.
Methods:
A total of 70 patients receiving diagnostic EGD (unsedated TN-EGD, sedated TO-EGD, and unsedated TO-EGD) were enrolled in this study and were evaluated by the following three criteria: (1) numbers of patients with excessive gag and/or cough reflex, (2) vital signs before and during the pharyngeal observation, and (3) response to the request for vocalization or breath-holding.
Results:
Unsedated TN-EGD, sedated TO-EGD, and unsedated TO-EGD were performed in 30, 20, and 20 patients, respectively. The rate of gag reflex was significantly lower in TN-EGD than in both types of TO-EGD (0% vs. 30%, chi-square test, p < 0.005). The changes in average values of both arterial oxygen saturation (SpO2) and pulse rate (PR) in TN-EGD were smaller than those in sedated TO-EGD (-0.23% vs. -1.23% in SpO2 and 1.57 vs. 8.11 bpm in PR, p < 0.01, respectively). Unsedated TN-EGD patients could respond to the instructions of utterance and breath-holding during the observation (p < 0.05, p < 0.001, respectively).
Conclusion:
Unsedated TN-EGD is safe and feasible for pharyngeal observation during normal EGD examination.
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