The role of the α₂-adrenoceptor agonist dexmedetomidine in postsurgical sedation in the intensive care unit

Dexmedetomidine was evaluated for sedation of 401 post-surgical patients in this double-blind, randomized, placebo-controlled, multicenter trial. Dexmedetomidine or saline was started on arrival in the intensive care unit (ICU) (1.0 mcg/kg for 10 minutes), then titrated at 0.2 to 0.7 mcg/kg/h to effect. Patients could be given propofol if necessary. Morphine was administered for pain. Sixty percent of the dexmedetomidine patients required no other sedative to maintain an RSS ≥ 3; 21% required < 50 mg propofol. In contrast, 76% of the control group received propofol; 59% required ≥ 50 mg. Dexmedetomidine patients required significantly less morphine for pain relief (P < .001). Continuously given throughout the ICU stay, dexmedetomidine had no effect on respiratory rate, oxygen saturation, duration of weaning, or times to extubation. Nurses judged the dexmedetomidine patients were easier to manage. Later, fewer dexmedetomidine patients remembered pain or discomfort. The majority of dexmedetomidine patients maintained blood pressures within normal range, without rebound. Hypertension, atelectasis, and rigors occurred more frequently in the control group, while hypotension and bradycardia occurred more frequently in the dexmedetomidine group. Preoperative cardiovascular conditions were not risk factors for dexmedetomidine patients.