Continuous oxygen insufflation would be a relatively easy initial step in treating hypoxemia and would add another mode of treatment in addition to CPAC and PEEP during one lung anesthesia. Our objectives with this study are to determine whether continuous insufflation of oxygen at zero airway pressure to the nonventilated lung will reduce intrapulmonary shunting and arterial oxygen denaturation during one lung anesthesia, as well as determine if the position of the pulmonary artery catheter (nonventilated lung vs. ventilated lung) is a significant consideration during one lung anesthesia. Presently, we are awaiting final IRB approval.