复合靶控输注异丙酚时瑞芬太尼抑制重症肌无力患者气管插管反应的药效学

目的 探讨复合靶控输注异丙酚时瑞芬太尼抑制重症肌无力患者气管插管反应的药效学.方法 拟行经胸骨正中劈开胸腺切除术的重症肌无力患者45例,ASA Ⅰ或Ⅱ级,TCI异丙酚和瑞芬太尼进行麻醉诱导,异丙酚血浆靶浓度为4 μg/ml,瑞芬太尼初始效应室靶浓度(Ce)为1.8 ng/ml,依次按2.7、4.0、6.0 ng/ml梯度递增,至患者可耐受喉麻管置入声门下进行气管内表麻后,进行气管插管.采用概率单位回归分析法分别计算瑞芬太尼抑制气管插管反应的Ce50和Ce95.结果 瑞芬太尼抑制气管插管反应的Ce50为2.2 ng/ml,其95%可信区间为2.0～2.3 ng/ml;抑制气管插管反应的Ce95为3.0 ng/ml,其95%可信区间为2.8～3.5 ng/ml.结论 复合靶控输注异丙酚(血浆靶浓度为4 μg/ml)时,瑞芬太尼抑制重症肌无力患者气管插管反应的Ce50和Ce95分别为2.2、3.0 ng/ml.

Pharmacodynamics of remifentanil blunting responses to tracheal intubation performed under peopofol anesthesia administered by TCI In patients with myasthenia gravis

Objective To investigate the pharmacodynamies of remifentanil blunting the responses to tracheal intubation performed under propofol anesthesia in patients with myasthenia gravis. Methods Forty-five ASA Ⅰ or Ⅱ patients with myasthenia gravis aged 18-64 yr weighing 45-95 kg scheduled for trans-stemal thymectomy were enrolled in this study. ECG, BP, HR, SpO2 and BIS were monitored. Anesthesia was induced with propofol and remifentanil both administered by TCI. The target plasma concentration (Cp) of propofol was set at 4 μg/ml during induction. The initial target effect-site concentration (Ce) of remifentanil was set at 1.8 ng/ml and was increased step by step to 2.7, 4.0 and 6.0 ng/ml until the patients could tolerate laryngoscopy and insertion of larynx unesthetic tube into subglottic space without body movement, coughing or bucking. Topical anesthesia of trachea was then performed by spraying 2% lidocaine 2 ml through the larynx anesthetic tube. Laryngoscope and larynx anesthetic tube were removed and the patients were ventilated with O2 through anesthetic mask for 1-2 min before tracheal intubation. The Ce50 and Ce95 (95% confidence interval) were calculated by Probit analysis. Results The Ce50 and Ce95 of remifentanil blunting responses to tracheal intubation performed with propofol administered by TCI was 2.2 ng/ml (95% CI 2.0-2.3 ng/ml) and 3.0 ng/ml (95% CI 2.8-3.5 ng/ml) respectively.Conclusion The Ce50 and Ce95 of remifentanil blunting responses to tracheal intubation performed under propofol anesthesia are 2.2 and 3.0 ng/ml respectively.