Hypotensive Anesthesia for Orthognathic Surgery

The overall objective of this double blinded, randomized controlled trial (RCT) is to compare specific outcomes of three medications (Dexmedetomidine, Nicardipine, and Labetalol) which are routinely used to lower blood pressure used during general anesthesia for orthognathic (jaw) surgery. The outcome measures for the study will be surgical field visibility, estimated blood loss, hemodynamic parameters, operation time, and adverse events. The specific objectives of this study are to compare: 1. Dexmedetomidine, Nicardipine, and Labetalol's effect on the quality of the surgical field. (Primary Outcome) 2. Dexmedetomidine, Nicardipine, and Labetalol's effect on estimated blood loss. 3. Dexmedetomidine, Nicardipine, and Labetalol's effect on hemodynamic parameters including systolic blood pressure, mean arterial pressure, and heart rate. 4. Dexmedetomidine, Nicardipine, and Labetalol's effect on operation time. 5. Dexmedetomidine, Nicardipine, and Labetalol's effect on adverse events. The investigators will evaluate healthy adult male and female patients who require jaw surgery at Boston Medical Center. The anticipated 90 participants will be randomized into three groups: ) A Labetalol group in which the patients receive hypotensive anesthesia with the aid of labetalol, 2) A Nicardipine group in which the patients receive hypotensive anesthesia with the aid of nicardipine, and 3) A Dexmedetomidine group in which the patients receive hypotensive anesthesia with the aid of dexmedetomidine. The time it will take for each individual participant ranges from 1-3 months. This time includes the pre-operative visit, the surgical procedure, a 1-week post-operation visit, and then followed for 30 days post-operatively after which the patient's participation in the study will conclude.