右美托咪定在全麻腹腔镜下胆囊切除术后抑制瑞芬太尼诱发痛觉过敏的半数有效量

ED50 of dexmedetomidine for prevention of remifentanil-induced hyperalgesia after laparoscopic cholecystectomy under general anesthesia

目的 测定右美托咪定抑制瑞芬太尼诱发痛觉过敏的半数有效量（ED5o）.方法 择期全麻腹腔镜下行胆囊切除术患者40例,随机分为对照组（C组）及右美托咪定组（D组）.D组在麻醉诱导前15 min采用序贯法泵注右美托眯定,初始剂量为0.8 μg/kg,相邻剂量之差为0.1 μg/kg;C组在麻醉诱导前15 min泵注等容积的生理盐水.记录各组气管拔管后30 min的VAS评分及恶心呕吐发生率.采用概率单位法计算右美托咪定抑制瑞芬太尼诱发痛觉过敏的ED50及其95％可信区间.结果 D组的VAS评分及恶心呕吐发生率低于C组（P＜0.05）.经计算右美托咪定抑制瑞芬太尼诱发痛觉过敏的ED50是0.51 μg/kg,95％可信范围为0.32～0.66 μg/kg.结论 右美托咪定抑制瑞芬太尼诱发痛觉过敏的ED50是0.51 μg/kg.

Objective To determine the ED50 of dexmedetomidine for prevention of remifentanil-induced hyperalgesia in patients after operation. Methods Forty patients undergoing laparoscopic cholecystectomy under general anesthesia were randomized into two groups： group C and group D. Patients in group IS） were given dexmedetomidine 15 min before the induction of anesthesia using up-and-down method. The initial close was 0.8 μg/kg and the dose adjustment space was 0.1 μg/kg. An equal volume of normal saline was given to the patients in group C. The VAS （30 min after trachea extubation） and the incidence of postoperative nausea and vomiting （PONV） were recorded. The ED50 of dexmedetomidine on remifentanil-induced hyperalgesia was determined by probit method. Results Compared with group C, VAS and the incidence of PONV were lower in group D （P〈0. 05）. The ED50 of dexmedetomidine for prevention of remifentanil-induced hyperalge- sia was 0.51 μg/kg, 95% CI： 0.32-0.66 μg/kg. Conclusion The ED50 of dexmedetomidine for inhibiting remifentanil-induced hyperalgesia in patients following laparoscopic cholecystectomy is 0. 51 μg/kg.