平均动脉压反馈丙泊酚闭环靶控输注在颅脑手术麻醉的应用

Mean arterial pressure as feedback variable of propofol closed-loop target controlled infusion in neurosurgical anesthesia

目的以平均动脉压（MAP）为反馈变量，探讨丙泊酚闭环靶控输注用于颅脑手术麻醉的可行性。方法46例择期行脑肿瘤切除患者，随机分为闭环组和靶控组，各23例。闭环组MAP反馈值设为70mmHg，两组丙泊酚血浆靶控浓度为3．0μg/ml，舒芬太尼0．3μg/（kg·h）持续静脉输注。记录两组麻醉前、插管即时、插管后5min、切皮、锯颅骨、切开脑皮质、切肿瘤1h、缝头皮等时间点的MAP、心率（HR）、心率变异指数（HRVI）、脑电双频指数（BIS）变化，计算丙泊酚的用量。结果在插管后5min、脑皮质操作、切肿瘤1h等时间点靶控组MAP下降较闭环组明显（P〈0．05）。两组患者的HR减慢，变化接近；在各观察时间点，靶控组HRVI低于闭环组，但差异无统计学意义（P〉0．05）。两组患者BIS大多处于低值区，在颅内操作期靶控组明显低于闭环组（P〈0．05）。闭环组丙泊酚用量（825．9±270．4）mg明显少于靶控组（1302．6±321．5）mg（P〈0．01）。结论以MAP为反馈变量调控丙泊酚闭环靶控输注麻醉可安全用于颅脑手术麻醉，术中循环稳定，减少丙泊酚维持所需用量。

Objective To investigate the feasibility of mean arterial pressure （MAP） as feedback variable of propofol closed-loop target controlled infusion in neurosurgical anesthesia. Methods 46 patients for elective brain tumor operation were divided into target controlled group and closed-loop group randomly,23 patients in each group. The MAP feedback value was set at 70 nun Hg in closed-loop group. The plasma target concentration of propofol was set at 3.0 μg/ml and sufentanyl was administrated at 0. 3 μg/（ kg ·h） in both two groups. The value of MAP, HR, Heart rate variation index （HRVI）, Bispectral index of EEG （BIS）, and propofol dosage were recorded at the time of before anesthesia,intubation ,5 min after intubation, skin incision, skull open, pallium procedure, 1 h tumor procedure, and skin suture. Results The descensus of MAP in targetcontrolled group was significant than closed-loop group at the time of 5 min after intubation, pallium procedure, and 1 h tumor procedure（P 〈0. 05）. The descensus of HR in two groups were similar,and no statistic difference （ P 〉 0. 05）, HRVI was the same. The BIS value was in lower degree in most patients, and the value of target controlled group was significantly lower than that of close-loop group during the intracranial procedure period （ P 〈 0. 05 ）. Propofol total dosage （ 825.9 ± 270. 4 ） mg of closed-loop group was significantly less than target controlled group （ 1302. 6±321.5） mg（P 〈 0.01 ）. Conclusion MAP was a safe feedback variance for adjusting propofol closed-loop target controlled infusion in craniocerebral operations,it is beneficial for stable circulation and less propofol total dosage.