全凭静脉麻醉期间右美托咪定对靶控输注丙泊酚用量及血流动力学的影响

目的：探讨右关托咪定（dexmedetomidine，DEX）对行全凭静脉麻醉患者靶控输注（target controlled infusion，TCI）丙泊酚用量及拔管期间血流动力学的影响。方法：选择拟于全麻下行经鼻蝶窦垂体瘤切除术的患者30例（ASA I～II级），随机分为两组，每组15例。试验组（D组）给予DEX负荷剂量0．5μg·kg-1，注药时间15rain，继以0．3μg·kg-1·h-1持续输注至修补硬膜时；对照纽（N组）在相同时间给予等容量生理盐水。两组麻醉诱导方法相同，术中以脑电双频指数（bispectral index，BIS）为麻醉深度监测指标，根据BIS值调节丙泊酚血浆靶浓度维持麻醉。记录拔管期间收缩压（SBP）、舒张压（DBP）和心率（HR），并计算心肌氧耗指数（RPP）；记录丙泊酚平均用量、用药前后BIS值、呼吸恢复时间、睁眼时间、拔管时间及术中不良反应。结果：①D组给予负荷剂量后，BIS值由（95±3）降至（77±11），差异有统计学意义（P〈0．01）。②与N组相比，D组丙泊酚用量减少28％，差异有统计学意义（P〈0．01）。⑧拔管期间SBP、DBP和HR与入室时比较，D组无明显变化，N组HR显著升高（P〈0．05）；D组拔管期间SBP、DBP、HR和RPP明显低于N组（P〈0．05）；④两组患者呼吸恢复时间、睁眼时间及拔管时间差异均无统计学意义；⑤两组不良反应（心动过缓、高血压、低血压）的发生率无显著性差异。结论：术中持续静脉输注DEX可减少TCI丙泊酚用量，能使BIS值进一步降低，产生良好镇静效应；同时可有效减轻拔管期间循环变化，降低RPP，减少心肌耗氧量，提高拔管质量。

The Effect of Dexmedetomidine on Target-controlled Infusion of Propofol Dosage and Hemodynamics in Total Intravenous Anesthesia

Objective： To investigate the effect of dexmedetomidine （DEX） on target controlled infusion （TCI） of propofol dosage and hemodynamics in total intravenous anesthesia （T1VA）. Methods： 30 patients （ASA I-II） who were scheduled for elective through the nose and sphenoid sinus pituitary tumor resection in total intravenous anesthesia. They were randomly divided into two groups （n=15）. 0.5μg·kg-1 of DEX were used in test group （group D） within 15 min as a bolus, and 0.3 μg·kg-1·h-1 of DEX were infused continuously until repair the dura mater. The same volume of normal saline were given at the same manner in control group （group N）. The same anesthetic induction method was used in the two groups. Bispectral index （BIS） was used as the index of depth of anesthesia, by which the target plasma concentration ofpropofol was adjusted to maintain the anesthesia. The average bolus ofpropofol, BIS, recovery time of breathing, eye opening time, extubation time and side-effect were recorded. The systolic blood pressure （SBP）, diastolic blood pressure （DBP）, heart rate （HR） were recorded during extubation. The value of rate pressure product （RPP） was also calculated. Results： ①After the loading dose, BIS decresed from 95± 3 to 77± 11 in group D （P〈0.01）. ②Compared with group N, the propofol consumption in group D decreased by 28%（P 〈0.01）. ③When patients arrived the operating room, compared with SBP, DBP, HR, group D has no significant change, HR in group N significantly increased （P〈0.05）. RPP, SBP, DBP and HR in group D were significantly lower than those in group N during extubation （P〈0.05）. ④No significant difference of recovery time of breathing, eye opening time and extubation time was observed between the two groups （P 〈 0.05）. ⑤No significant difference of the incidence rate of adverse reactions （such as bradycardia, hypertension, hypotension） had been observed（P 〈 0.05）. Conclusion： Intraoperative continuous infusion of DEX can reduce the TCI propofol dosage and BIS, resulting in a good sedative effect. It can effectively reduce the cyclic change during extubation, RPP and the myocardial oxygen consumption, and can improve the extubation quality.