Abstract： Objective To explore the role and safety of right dexmedetomidine in the analgesic and sedative treatment for brain injury patients and evaluate the significance of analgesic and sedative treatment for brain injury patients.Methods This prospective clinical study induced 28 patients with moderate brain trauma scored with GCS 7 ～ 13 points without hypotension,shock and hypertension.The patients were treated with right dexmedetomidine in loading dose of 0.5 ～ 1.0 μg/kg and maintenance dose given by continuous infusion in rate of 0.3 ～ 0.5 μg/ ( kg · h) for 30 minutes.Blood pressure,heart rate,respiration,arterial blood gas,selected sedation score ( self - rating anxiety scale:SAS) and analgesic score (verbal rating scale:VRS,faces pain scale:FPS),psychic symptoms (anxiety,agitation) were monitored and documented for the comprehensive assessment of the efficacy of this treatment whether that reached up to the scratch of ideal sedation and analgesia.Results The sedative and analgesic efficacy of this treatment was found in 85.71％ of patients,and it was up to 92.85％ after morphine added.Blood pressure and heart rate decreased by 14 -20％ after treatment,and only a few patients had them dropped down by 25％ under the loading and maintaining doses.There was no significant inhibition of respiration,and other adverse reactions were not found.Conclusions Right dexmedetomidine was effective in patients with moderate brain injury.It caused certain degree of decrease in blood pressure and heart rate,but it was safe within the therapeutic dose.