The efficacy, side effects, and recovery characteristics of dexmedetomidine versus propofol when used for intraoperative sedation

We evaluated the cardio-respiratory effects of equi-sedative doses of dexmedetomidine and propofol for intraoperative sedation. Secondary comparison end points were time to achieve and terminate sedation and postoperative analgesia and psychomotor performance. Forty patients scheduled for elective surgery provided informed consent and were randomized equally to receive either dexmedetomidine (1 mug/kg initial loading dose for 10 min; maintenance, 0.4-0.7 mug . kg(-1) . h(-1)) or propofol (75 mug . kg(-1) . min(-1) x 10 min; maintenance, 12.5-75 mug . kg(-1) . min(-1)). Hemodynamic variables (heart rate and mean arterial blood pressure), sedation (visual analog scale and Observer Assessment of Alertness/Sedation), bispectral index score of sedation, ventilation (respiratory rate, 0, sat, and ETCO2), psychomotor performance (digital symbol substitution test), and pain (visual analog scale) were determined during surgery and up to 95 min after surgery. Intraoperative sedation levels were targeted to achieve a bispectral index score of 70-80. Patient demographics, ASA class, surgical procedure, and baseline cardio-respiratory variables were similar between groups. Sedation was achieved more rapidly with propofol but was similar between groups 25 min after initiating infusions. The average infusion rate for dexmedetomidine was 0.7 mug . kg(-1) . h(-1) and 38 mug . kg(-1) . min(-1) for propofol. There were no differences between groups in psychomotor performance and respiratory rate during recovery. The previous use of dexmedetomidine resulted in more sedation, lower blood pressure, and improved analgesia (less morphine use) in recovery.