 5. Following surgery, the patient will be taken to the post anesthesia care unit PACU and set up with standard ASA monitoring as well as end-tidal CO2 via nasal cannula. A hydromorphone patient controlled analgesia PCA pump will be set-up by nursing and given to the patient. Standard dosing of 0.2 mg bolus, every 6 minutes with a maximum 2 mg will be the starting dose as is standard for these patients post-operatively. 