Fig. 7. Mean (± SD) change in heart rate ( top ) and systolic blood pressure ( bottom ) from baseline (before dexmedetomidine infusion) for the four doses: control (0 μg · kg−1· h−1) and infusions of 2, 4, and 6 μg · kg−1· h−1dexmedetomidine (for 10 min) (corresponding to 0.33, 0.66, and 1.0 μg/kg) recorded for 24 h. General anesthesia and surgery occurred between 1 and 4 h.