Objective To analyze the effect of dexmedetomidine hydrochloride injection on patients with craniocerebral disease who has no artificial airway in the process of bronchoalveolar lavage treatment.Methods Forty-six patients (age 17-28,average age 56.6±9.2,26 men and 20 women) with craniocerebral disease who has no artificial airway were selected,and were treated by bronchoalveolar lavage for lung infection.The patients were randomly divided into two groups,control and test group.The control group (n=23) received midazolam for sedative and the test group (n=23) received dexmedetomidine hydrochloride for sedative while they were in the process of bronchoalveolar lavage treatment.Heart rate,mean arterial pressure and blood oxygen saturation of fingers collected from patients before and during the process of bronchoalveolar lavage were compared.Results In the process of bronchoalveolar lavage treatment,the minimum blood oxygen saturation of finger artery from the control group was lower than that from the test group,the fastest heart rate from the control group was greater than that from the test group,and the lowest mean arterial pressure from the control group was lower than that from the test group (P＜0.05).In two groups,heart rate in the process of bronchoalveolar lavage treatment was faster than that from before the treatment,while both mean arterial pressure and blood oxygen saturation of finger artery were decreased (P＜0.05).Conclusions Continuous intravenous pumping of dexmedetomidine hydrochloride on patients with craniocerebral disease who has no artificial airway during the process of bronchoalveolar lavage treatment is effective and safe,and it has less inhibitory effect on respiratory function and blood pressure.