Mandibular Advancement Bite Block Efficacy Observational Study

During endoscopic examinations, especially upper gastrointestinal, bile duct, or bronchoscopic examinations, the endoscope need to be placed through the mouth. A bite block is used to protect vulnerable endoscope and protect patient's teeth. During sedative endoscopic exams, respiratory depression, apnea or upper airway obstruction will occur under the influence of the sedative medications. Serious adverse events may occur such as hypoxemia. A nasal airway, Larson's maneuver, jaw thrust or chin lift may be needed to open airways. Mandibular advancement devices has been widely used in treating obstructive sleep apnea. A modified bite block that provides mandibular advancement could provide entry inlet of endoscope as well as provide mandibular advancement to provide patent airway during sedative endoscopy. In this study, we group the patients into test group using mandibular advancement bite block and a control group using standard bite block. After anesthetic induction, gastric endoscopy was performed. Degree of upper airway obstruction will be evaluated and recorded. Differences between the two groups will be evaluated.