电针复合TCI靶控输注在单肺通气食管癌开胸手术麻醉中的应用与安全性＊

目的 探讨电针复合靶控输注（Target Controlled Infusion， TCI）在单肺通气食管癌开胸手术麻醉中的应用价值。方法 选取于我院拟行单肺通气食管癌开胸切除手术患者60例作为研究对象。随机将其分为试验组与对照组，对照组30例采取气管插管全麻及TCI靶控输注维持麻醉深度，试验组30例则在对照组方案基础上辅助电针麻醉，记录两组患者手术麻醉时间、药物用量、苏醒时间、并发症；以及术前（T_Ⅰ）、插管前即刻（T_Ⅱ）、插管后1 min（T_Ⅲ）、切皮即刻（T_Ⅳ）、去骨时（T_Ⅴ）、拔管即刻（T_Ⅵ）时平均动脉压（MAP）、平均心率（HR）、BIS值；术前、术后1天、术后3天简易智能精神状态检查量表（MMSE）；并于麻醉诱导前（T₀）、手术开始2 h（T₁）、术后1天（T₂）、术后3天（T₃）时抽取患者外周静脉血检测IL-1β、IL-6、IL-10、TNF-α浓度。结果 试验组手术用时、麻醉时间略低于对照组，但差异无统计学意义（P>0.05），试验组异丙酚、舒芬太尼用量以及苏醒时间均明显低于对照组（P<0.05）；T_Ⅱ时两组平均动脉压（Mean Arterial Pressure， MAP）、心率（Heartrate， HR）较术前明显降低，且试验组MAP明显低于对照组（P<0.05），但两组T_Ⅱ时HR比较无显著差异（P>0.05）；T_Ⅲ、T_Ⅵ时对照组MAP、HR明显高于T_Ⅰ时，而试验组MAP、HR与T_Ⅰ比较无显著差异（P>0.05）。术后1天、3天试验组简易智能精神状态检查量表（Mini-Mental State Examination， MMSE）评分低于对照组，有显著性差异（P<0.05）。T₁、T₂、T₃时试验组白介素-1β（IL-1β）、白介素-6（IL-6）、肿瘤坏死因子（Tumor Necrosis Factor-α， TNF-α）水平明显低于对照组（P<0.05），白介素-10（IL-10）水平明显高于对照组（P<0.05）。结论 采用电针复合TCI靶控输注麻醉方案可有效提升单肺通气食管癌开胸手术麻醉效果，能够降低患者术后认知功能障碍发生风险。     

重复腋路臂丛麻醉不同穿刺定位法的效果比较

目的：观察应用不同穿刺定位法施行重复腋路臂丛阻滞麻醉效果。方法：３２４例随机分为两组，在局麻药浓度、容量相同的情况下，Ａ组采用一针穿刺单次给药逐次移位定向挤压法，１６２例中，臂丛阻滞７３０次；Ｂ组采用一针穿刺单次给药法，１６２例中，臂丛阻滞６７０次。结果：在诱导时间、维持时间和阻滞完全方面，Ａ组均明显优于Ｂ组。结论：臂丛神经处于椎前筋膜及其延续的筋膜间隙中，因此，一针穿刺单次给药能获得有效的阻滞。     

脑电双频指数指导老年病人异丙酚麻醉诱导用量

[目的]通过监测老年病人麻醉诱导时脑电双频指数(BIS)的变化,探讨既能维持足够麻醉深度又能避免严重低血压的异丙酚诱导用量。[方法]40例ASA II～I级的老年病人(65～85岁),随机分成两组。A组静脉注射异丙酚1.6 mg/kg;B组静脉注射异丙酚,其用量是使BIS下降到40～50时的用量。两组均复合维库溴铵0.1 mg/kg和瑞芬太尼1ug/kg诱导后行气管插管分别记录基础值、插管前、插管后1 min、5 min和10 min时的收缩压(SBP)、舒张压(DBP)、平均动脉压(MAP)、心率(HR),同时记录诱导异丙酚用药量和BIS的变化。[结果]A组异丙酚诱导用药量(99.7±18.05)mg,平均(1.64±0.7)mg/kg,B组(82.9±12.5)mg,平均(1.35±0.5)mg/kg,差异有统计学意义(P﹤0.05)。A组血压(BP)和BIS比B组明显降低。[结论]老年病人异丙酚麻醉诱导的合适用量为(1.35±0.5)mg/kg;既能维持老年人足够的麻醉深度又能避免严重低血压的发生。     

新麻醉药静松灵生物转化的研究

静松灵[2-(2,4-二甲基苯胺基)-4,5-二氢噻唑,XT]是国内合成的麻醉物,经ip给药后,从大鼠尿中分离、纯化、鉴定了四个代谢产物。MB₁即XT原形;MB₃及MA₂互为异构体,分别为2位、4位甲基氧化为羧基的产物;MA₁则4位甲基氧化为羧基,二氢噻唑环中4¹位亚甲基氧化为羰基。初步实验表明:代谢产物MB₃,MA²,MA₁的药效与毒性均远低于原形药,大鼠与小鼠对XT的转化机制相近,但也存在种属的差异。     

Influence of anaesthesia and muscle relaxation on intubating conditions and sympathoadrenal response to tracheal intubation

Background : The study aimed to assess the relative influence of anaesthesia and muscle relaxation on intubating conditions and the haemodynamic and catecholamine responses to tracheal intubation.
Methods : Sixty ASA 1 or 2 patients were randomly assigned to one of four groups (15 patients each) that differed in the depth of anaesthesia (thiopentone plus fentanyl 2.5 μg kg^-1 or thiopentone alone) and the degree of vecuronium–induced neuromuscular block (100% or _>: 65%) at intubation. Muscle relaxation was measured at 0.1 Hz by means of mechanomyography. Heart rate (HR) and mean arterial blood pressure (MAP) were measured before and after induction of anaesthesia, and 1 min and 5 min following intubation, while adrenaline (A) and noradrenaline concentrations (NA) were determined from arterial blood samples.
Results : Intubating conditions were improved primarily by providing complete muscle relaxation at the adductor pollicis muscle (P<0.001) and to a lesser extent by adding fentanyl to thiopentone (P=0.04). The response of HR and MAP to tracheal intubation was attenuated mainly by fentanyl (P<0.001). Complete muscle relaxation further diminished the response of MAP to intubation (P=0.03). Changes in A and NA were dependent on the depth of anaesthesia only (P =>0.01).
Conclusion : The results of the study demonstrate that the sympathoadrenal response to intubation is attenuated by adding fentanyl (2.5 kg^-1) to an induction regimen with thiopentone, whereas provision of complete muscle relaxation at the adductor pollicis muscle is necessary to attain smooth intubating conditions.     

Effect of thoracic epidural etidocaine 1.5% on somatosensory evoked potentials, cortisol and glucose during cholecystectomy

The effect of thoracic (T7-8) epidural etidocaine 1.5%, 9 ml, and continuous per- and postoperative epidural infusion of etidocaine 1.5%, 4 ml/h, on early (less than 500 ms) somatosensory evoked potentials (SEPs), and cortisol and glucose in plasma during cholecystectomy, was examined in ten patients. Spread of analgesia (pin-prick) was T3 (T1-T3) to L2 (T11-L3) 35 min after injection of etidocaine, and T3 (T2-T4) to T12 (T8-L4) 3 h after surgical incision (median (range)). Before operation, epidural etidocaine had no significant effects on peak-to-peak amplitude of SEPs to electrical stimulation at the L1, T10 or T6 dermatomal level (P greater than 0.09). SEPs were abolished in only two patients at T6, and no patient had SEPs abolished at T10 or L1. The plasma concentrations of cortisol and glucose were significantly increased 20 min after surgical incision and remained increased throughout the study. No correlation was found between the block-induced decrease in the peak-to-peak amplitude at T6 or T10 and increase in plasma cortisol, except for a negative correlation at T10 and the initial increase in cortisol (Rs = 0.72, P = 0.03). In conclusion, thoracic epidural administration of 9 ml of etidocaine 1.5% does not provide total afferent somatic blockade assessed by SEP and the stress response to cholecystectomy.     

Effects of low-dose propofol administration on central respiratory drive, gas exchanges and respiratory pattern

The effects of sedative-hypnotic doses of propofol on respiratory drive and pattern have not yet been extensively described. Repeated small boluses of propofol (0.6-0.3 mg.kg-1) were administered to ten ASA I patients undergoing carpal tunnel release using regional anaesthesia. Airway pressure, capnography and pneumotachography were continuously recorded. With respect to basal values, no significant variations of respiratory rate, minute volume, tidal volume, inspiratory and expiratory time, total expiratory cycle, Ti/Ttot, TV/Ti, P0.1, EtCO2 and blood gas analysis were observed. Low doses of propofol, to maintain conscious sedation of light sleep, have not been shown to cause respiratory depression.     

Fluctuations in Tumor Blood Flow under Normotension and the Effect of Angiotensin II-induced Hypertension

To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension.     

Age, fiber type composition and in vitro contracture responses in human malignant hyperthermia

Muscle fiber typing and in vitro contracture tests were performed in 59 patients investigated for susceptibility to malignant hyperthermia (MH). Eighteen patients were found to be susceptible to MH. There was no difference in age or fiber type distribution between MH susceptible and non-susceptible patients. No correlation was found between age and fiber type distribution. Separate analyses for each diagnostic group revealed no relationship between age or fiber type distribution and response to halothane or caffeine. When all caffeine results were pooled, however, there was a significant effect of age on the caffeine specific concentration (the concentration eliciting a contracture of 1 g), but not on the caffeine threshold concentration (the minimal concentration eliciting an increase in tension). It is concluded that age and fiber type distribution have no influence on MH diagnosis, if the protocol of the European MH Group for evaluation of susceptibility to MH is followed.