右美托咪啶对舒芬太尼抑制甲状腺切除术患者切皮时体动反应半数有效效应室靶浓度的影响

目的 评价右美托咪啶对舒芬太尼抑制甲状腺切除术患者体动反应的半数有效效应室靶浓度(EC50)的影响.方法 择期行甲状腺双叶次全切除术患者,性别不限,ASA分级Ⅰ或Ⅱ级,年龄20～64岁,体重指数20～2.5 kg/m2,采用随机数字表法,将其随机分为2组,D组经10 min静脉输注右美托咪啶0.6 μg/kg,C组给予等容量生理盐水,停止给药后5 min时开始靶控输注异丙酚,血浆靶浓度为3.0 μg/ml,输注10 min时,2组开始靶控输注舒芬太尼,第1例患者的效应室靶浓度为0.20ng/ml,输注舒芬太尼3 min时置入喉罩,保留自主呼吸,待舒芬太尼达到目标靶浓度后,开始手术.根据切皮时是否发生体动反应确定下一例患者舒芬太尼的靶浓度,相邻靶浓度比值为1.2.采用序贯法计算舒芬太尼抑制切皮时体动反应的EC50及其95%可信区间(95%CI).结果 C组和D组样本数分别为19和20,舒芬太尼抑制切皮时体动反应的EC50分别为0.1454 ng/ml(95%CI 0.1339～0.1580 ng/ml)和0.1148 ng/ml(95%CI 0.1055～0.1249 ng/ml),D组EC50低于C组(P＜0.05).结论 术前静脉注射右美托咪啶0.6 μg/kg可降低舒芬太尼抑制甲状腺切除术患者切皮时体动反应的EC50.

Abstract：

Objective To investigate the effect of dexmedetomidine on median effective target effect-site concentration ( EC50) of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy. Methods Thirty-nine ASA I or II patients of both sexes aged 20-64 yr with a body mass index of 20-25 kg/m2 undergoing bilateral subtotal thyroidectomy were randomly divided into 2 groups: control group (group C) and dexmedetomidine group (group D). The patients were premedicated with intramuscular phenobarbital 0.1 g and scopolamine 0.3 mg. In group D dexmedetomidine 0.6 μg/kg was injected iv over 10 min at S min before induction of anesthesia. Anesthesia was induced with target-controlled infusion (TCI) of propofol and sufentanil. The target plasma concentration of propofol was set at 3.0 μg/ml which was maintained until the end of operation. TCI of sufentanil was started at 10 min after initiation of propofol TCI. The initial target effect-site concentration was set at 0.20 ng/ml and decreased/increased by 20% in the next patient according to whether the patient's body moved or not within 1 min after skin incision. Laryngeal mask airway was inserted at 3 min after initiation of sufentanil TCI. Spontaneous breathing was maintained. Skin incision was made at 10 min after initiation of sufentanil TCI. The EC50 and 95% confidence interval (CI) of sufentanil inhibiting skin incision-evoked body movement were calculated with sequential method. Results EC50, of sufentanil was 0.1148 ng/ml (95% CI 0.1055-0.1249 ng/ml) in group D and 0.1454 ng/ml (95% CI 0.1339-0.1580 ng/ml) in group C, and was significantly lower in group D than in group C. Conclusion Dexmedetomidine 0.6 μg/kg infused iv before operation can reduce the EC50 of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy.

Effect of dexmedetomidine on median effective target effect-site concentration of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy

Objective To investigate the effect of dexmedetomidine on median effective target effect-site concentration ( EC50) of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy. Methods Thirty-nine ASA I or II patients of both sexes aged 20-64 yr with a body mass index of 20-25 kg/m2 undergoing bilateral subtotal thyroidectomy were randomly divided into 2 groups: control group (group C) and dexmedetomidine group (group D). The patients were premedicated with intramuscular phenobarbital 0.1 g and scopolamine 0.3 mg. In group D dexmedetomidine 0.6 μg/kg was injected iv over 10 min at S min before induction of anesthesia. Anesthesia was induced with target-controlled infusion (TCI) of propofol and sufentanil. The target plasma concentration of propofol was set at 3.0 μg/ml which was maintained until the end of operation. TCI of sufentanil was started at 10 min after initiation of propofol TCI. The initial target effect-site concentration was set at 0.20 ng/ml and decreased/increased by 20% in the next patient according to whether the patient's body moved or not within 1 min after skin incision. Laryngeal mask airway was inserted at 3 min after initiation of sufentanil TCI. Spontaneous breathing was maintained. Skin incision was made at 10 min after initiation of sufentanil TCI. The EC50 and 95% confidence interval (CI) of sufentanil inhibiting skin incision-evoked body movement were calculated with sequential method. Results EC50, of sufentanil was 0.1148 ng/ml (95% CI 0.1055-0.1249 ng/ml) in group D and 0.1454 ng/ml (95% CI 0.1339-0.1580 ng/ml) in group C, and was significantly lower in group D than in group C. Conclusion Dexmedetomidine 0.6 μg/kg infused iv before operation can reduce the EC50 of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy.