RESUMEN
Objective Evaluate the interaction between dexmedetomidine and propofol for seda-tion induction.Methods Seventy-five patients who undergoing elective surgery under general anesthe-sia,36 males and 39 females,aged 18-65 years,BMI 20-25 kg/m2,ASA physical status Ⅰ or Ⅱwere randomly divided into three groups (n=25 ):propofol group (group A),dexmedetomidine group (group B),propofol combined dexmedetomidine group(group C),each group was divided into 5 groups according to different drug doses,the dose ratio of the adjacent two groups was 1.25,and the median effective dose (ED50)value was calculated by the point oblique method.Results The hyp-notic dose of propofol ED50in group A was 1.25 mg/kg (0.90-1.45 mg/kg),and the anesthetic induction dose of dexmedetomidine ED50in group B was 1.35 μg/kg (0.95-1.50 μg/kg),and the hypnotic dose of propofol and dexmedetomidine ED50in group C was 0.65 mg/kg (0.50-0.90 mg/kg)and 0.40 μg/kg (0.34-0.65 μg/kg)respectively.Conclusion Dexmedetomidine combined with propofol can produce a sig-nificant hypnotic effect,while reducing the impact on the circulation.