羟考酮联合七氟醚抑制全麻手术喉罩置入时患者心血管反应的ED50测定OA

Objective To determine the median effective dose(ED50)of oxycodone combined with sevoflurane for suppressing cardiovascular responses to laryngeal mask airway(LMA)insertion during induction of general anesthesia.Methods Thirty-two patients scheduled for elective surgery under general anesthesia with LMA insertion were en-rolled.All patients were American Society of Anesthesiologists(ASA)physical status Ⅰ-Ⅱ,aged 18-65 years,with a body mass index(BMI)of 18-24 kg/m2 and an expected surgical duration of＜2 h.A sequential allocation method was used.The first patient received intravenous oxycodone at 0.10 mg/kg,followed 3 min later by inhalation of 8％sevoflu-rane for 1 min.The sevoflurane concentration was then adjusted to 4％.LMA insertion was performed when the end-tidal sevoflurane concentration reached 4％and the Modified Observer's Assessment of Alertness/Sedation(MOAA/S)score was＜1.Heart rate(HR),systolic blood pressure(SBP),diastolic blood pressure(DBP),mean arterial pressure(MAP),peripheral oxygen saturation(SpO2),bispectral index(BIS),and adverse events were recorded at each time point.The ED50 and ED95 were calculated using the probit method.Results Compared with baseline values on admis-sion(T1),SBP,DBP,MAP,and BIS decreased at all time points after induction of anesthesia(P＜0.05),whereas SpO2 increased(P＜0.05).HR fluctuated significantly during the observation period(P＜0.05).One case of coughing occurred at an oxycodone dose of 0.06 mg/kg,while one case of movement response occurred at each of the doses of 0.05,0.07,and 0.09 mg/kg.The ED50 of oxycodone combined with sevoflurane for suppressing cardiovascular respon-ses to LMA insertion was 0.070 mg/kg(95％CI:0.056-0.085 mg/kg),and the ED95 was 0.106 mg/kg(95％CI:0.082-0.131 mg/kg).Conclusion Oxycodone combined with sevoflurane effectively suppresses cardiovascular respon-ses to LMA insertion during general anesthesia.The ED50 and ED95 of oxycodone were 0.070 mg/kg and 0.106 mg/kg,respectively.A dose of 0.1 mg/kg may be appropriate for clinical use,while a starting dose of 0.07 mg/kg may be con-sidered in high-risk patients.This regimen may be particularly suitable for patients in whom coughing responses should be minimized.