c) Maintenance of anesthesia i. Sevoflurane 1.1 minimum alveolar concentration (MAC) ii. If heart rate or blood pressure increase > 20% above baseline (tachycardia as determined the morning of surgery in the holding area), anesthesiologist will administer1 microgram/kg fentanyl as bolus. May repeat as often as every 10 minutes. Maximum 8 doses.