The purpose of this study is to assess the utility of the ExSpiron Respiratory Variation Monitor in patients undergoing an interventional procedure with anesthesia. The primary outcome measure will be the average minute ventilation of the patient during the procedure. This study will also examine the correlation between clinical interventions such as drug administrations or airway maneuvers with data from the monitor. Additionally the study may provide information about the ability of this new monitoring system to prevent hypoxemia during these procedures and to consider its utility, compared with capnography, to detect hypopnea.