Purpose: To assess the utility of a new medical device that monitors a patient's breathing during medical procedures in which a patient is sedated, but not mechanically ventilated. In minor procedures, such as endoscopy (where the doctor examines a patient's digestive tract by a TV camera inserted through the mouth), patients do not require general anesthesia, in which a machine would take over their breathing while they are unconscious for surgery. However, during endoscopic procedures it is sometimes difficult for the anesthesiologist to monitor the patient's breathing—specifically, to monitor changes in breathing patterns and the adequacy of breathing. In endoscopy procedures, the room is darkened, and the patient's mouth is generally occupied by the endoscope. While the anesthesiologist can listen to the patient's breathing sounds with a stethoscope, this type of monitoring can only be done periodically, and there is limited ability to gauge the adequacy of ventilation. This study will use the ExSpiron Respiratory Volume Monitor (RVM), which measures non-invasive minute ventilation (MV), tidal volume (TV) and respiratory rate (RR), in patients undergoing an endoscopic procedure to provide additional information regarding the effects of clinical interventions such as drug administrations or airway maneuvers on the patient's respiratory status.