Median effective dose of remimazolam combined with sufentanil for inhibition of nasopharyngeal airway insertion reaction in elderly patients
Objective To calculate median effective dose(ED50)of remimazolam combined with sufentanil for inhibition of nasopharyngeal airway insertion reaction in elderly patients.Methods Thirty-eight patients,aged≥65 years,BMI 18-25 kg/m2,ASA physical statusⅠ-Ⅲ,undergoing elective cata-ract surgery under nasopharyngeal airway were selected.Patients received intravenous sufentanil injections of 0.1 μg/kg,followed by intravenous remimazolam injection 3 minutes later,then nasopharyngeal airway in-sertion after 2 minutes.The initial dose of remimazolam was 0.2 mg/kg and adjusted by 0.01 mg/kg,based on the modified Dixon sequential method.A positive reaction was defined as head shaking,choking,body movement,an increase in HR>20%of the basal value,or an increase in SBP or DBP>20%of the basal value at the time of nasopharyngeal airway placement.The procedure was stopped after seven crossovers.The ED50,95%effective dose(ED95)of remimazolam,and 95%confidence intervals(CI)were calculated by probabilistic unit(Probit)regression analysis.Results When combined with sufentanil,the ED50 and ED95 of remimazolam for inhibition of nasopharyngeal airway insertion in elderly patients was 0.193 mg/kg(95%CI 0.191-0.195 mg/kg)and 0.209 mg/kg(95%CI 0.205-0.213 mg/kg),respectively.Conclusion The ED50 of remimazolam combined with sufentanil for inhibition of nasopharyngeal airway in-sertion reaction in elderly patients were 0.193 mg/kg(95%CI 0.191-0.195 mg/kg).