Purpose: For the pilot phase, if the visual memory assessment test developed in this study can adequately assess periods of amnesia during the procedure, then it can be used for the phase of the study that randomizes patients to moderate or deep sedation. The purpose of the randomized phase is to compare the rate of amnesia and respiratory depression in patients who receive moderate sedation to those that received deep sedation. The goal is to determine whether moderate sedation could provide a safer sedation while still resulting in adequate amnesia of the procedure. Secondary goals would be to compare the duration of sedation, the success of the procedures for which the patient is sedated, procedural difficulty, the rate of hypotension and other adverse events, and the patient perception of the quality of the sedation (pain or recall of procedure).