Airway devices are provided for introducing an endoscope into a patients gastrointestinal system that include a tubular proximal portion sized for placement in an oral cavity and including a passage for receiving an endoscope therethrough, and a curved distal portion. The distal portion may have a “C” shaped wall defining a channel extending from the passage to a distal tip of the distal portion. The proximal portion may include a flange for placement adjacent the patients teeth when the airway device is inserted into the oral cavity, and the airway device may include sampling and fluid delivery lumens including ports on the face of the flange. The sampling lumen may include an inlet port within the passage, and the fluid delivery lumen may include an outlet port communicating with the channel such that the outlet port is offset distally relative to the inlet port.