Patients with atrial fibrillation that are scheduled for a catheter ablation procedure will be placed in one of two groups (to receive either a propofol infusion as their primary general anesthetic, or to receive inhaled sevoflurane as the primary general anesthetic). One of these two medications would be used by anesthesia during the procedure. The study will assess the outcomes of each medication.

This study will compare 0.1mg and 0.05mg of spinal morphine for postoperative pain after scheduled, elective Cesarean delivery. All patients will receive a spinal anesthetic (single injection in the lower back to numb patients from the waist down) for operative anesthesia and will be
randomized into one of two groups: (group 1) 0.1mg spinal morphine and (group 2) 0.05mg spinal morphine. This will be a randomized, single blinded study.

This study will compare the safety and effectiveness of a new facemask, the Tao mask, as compared to the standard mask for manual ventilation of patients with BMIs of 40 or greater who are undergoing elective surgery. The Tao mask and the standard mask will both be used for each patient but the order of evaluating the masks will be randomized.