A Dual Channel Supraglottic Airway Device (LMA Gastro) for Oxygenation in Patients Undergoing ERCP

PRIMARY OBJECTIVE: I. To compare the incidence of desaturation (oxygen saturation \[SpO2\] \< 90%) between patients undergoing ERCP with LMA Gastro versus (vs) standard nasal cannula. SECONDARY OBJECTIVES: I. To evaluate the incidence of additional airway maneuvers (jaw thrust/chin lift/placement of oral airway or/nasal trumpet/intubation). II. To evaluate the incidence of withdrawal of duodenoscope from the airway to facilitate airway support. III. To evaluate the incidence of adverse events. IV. To evaluate times related to anesthesia and procedure (defined as "anesthesia start to anesthesia end" and "procedure start to procedure end" respectively). V. To evaluate time from procedure end to anesthesia end. VI. To describe hemodynamics within the two groups (recorded blood pressures, heart rates, oxygen saturations, and end tidal carbon dioxide \[CO2\]). VII. To evaluate anesthesiologist placing the device (training video viewed, number of practice attempts, years of experience). OUTLINE: Patients are randomized to 1 of 2 arms. ARM I: Patients undergo ERCP with LMA Gastro. ARM II: Patients undergo ERCP with standard nasal cannula.