Objective To observe the effects of propofol or sevoflurane combined with remifentanil on cerebral blood flow (CBF) and cerebral autoregulation in patients undergoing gynecologic laparoscopic surgery. Methods Forty patients were randomly divided into two groups: the propofol group (group P, n=20) and the sevoflurane group (group S, n=20). Anaesthesia was induced with target-controlled infusion (TCI) of propofol and remifentanil in group P, with an inhaled induction of sevoflurane and TCI of remifentanil in group S, respectively. The depth of anesthesia was regulated according to bispectral index (BIS). The pressure of end-tidal carbon dioxide (P_(ET)CO_2) was kept at 35-40 mmHg by mechanical ventilation. The mean arterial pressure (MAP), heart rate (HR), pressure of arterial carbon dioxide (PaCO_2), P_(ET)CO_2, time-averaged peak flow velocity (TAP) and the transient hyperaemic response ratio (THRR) were recorded at 7 different time points: supine position (T_1) and supine lithotomy position before induction (T_2), the instant and 5 min after tracheal intubation (T_3,T_4), the instant and 15 min after abdominal CO_2 insufflation and trendelenburg-lithotomy position (T_5,T_6), and 10 min after the deflation abdomen (T_7), respectively. Results Compared with the baseline values at T_1, TAP was not significantly changed at T_2, T_5, or T_6 in group P, but was markedly decreased at T_3, T_4 and T_7. TAP in group S only decreased at T_4 and T_7, while it was much higher than that in group P at T_3. In group S, THRR was markedly lowered at T_3 compared with that at T_1; but in group P, it showed a significant increase at T_3. Conclusions Combined with remifentanil, propofol decreased CBF, but has no effect on the brain self-regulation. When inhaled in high concentrations, sevoflurane significantly reduces the brain self-regulation. Intraoperation pneumoperitoneum and postural factor significantly increase CBF, playing a stronger role than the narcotic drugs in clinical dosage (propofol, sevoflurane), without any influence on the brain self-regulation.%目的 研究妇科腹腔镜术中七氟醚或异丙酚联合瑞芬太尼对脑血流量(cerebral blood flow,CBF)和脑血管自身调节能力的影响.方法 择期行妇科腹腔镜手术患者40例,随机分为七氟醚组(S组,n=20)和异丙酚组(P组,n=20).两组分别采用七氟醚或异丙酚复合瑞芬太尼诱导和维持麻醉,在诱导前水平仰卧位(T_1)、水平截石位(T_2)、诱导插管后即刻(T_3)、诱导插管后5 min(T_4),气腹头低位后即刻(T_5)、气腹头低位后15 min(T_6)、气腹放气后10 min(T_7)观察各时间点的平均动脉压(mean arterial pressure,MAP)、心率(heart rate,HR)、PaCO_2、P_(ET)CO_2、大脑中动脉时间平均峰值流速(time-average peak flow velocity,TAP)和脑短暂充血反应(transient hyperaemic response, THR).结果 与TI时点相比,P组TAP在T_2、T_5、T_6时点均无显著变化,而在T_3、T_4、T_7时点明显降低,S组仅在T_4、T_7时点明显下降,T_3时点明显高于P组,且与T_1时点无显著差异;S组THR反应率(THRR)在T_3时点与T_1时点相比显著下降,且低于P组.结论 联合瑞芬太尼麻醉诱导和维持时,异丙酚可降低CBF,但对脑血管自身调节能力无明显影响,而七氟醚在吸入高浓度时能明显降低脑血管自身调节能力;CO_2气腹与头低截石体位可显著升高CBF,其作用明显强于临床常用剂量的麻醉药物,但对脑血管自身调节能力无明显影响.
展开▼
