The Efficacy of Distal Pharyngeal Airway for Oxygenation During TEE

Inclusion Criteria: * Age \> or = 18 years old * Patients willing to participate and provide an informed consent * Patients scheduled to undergo an elective TEE procedure. Exclusion Criteria: * Patients with history of uncontrolled gastroesophageal reflux disease * Patients with anatomical airway obstruction * Have any condition that, in the opinion of the investigator, would compromise the well-being of the patient or the study or prevent the patient from meeting or performing study requirements