不同浓度吸入麻醉药对脑电双频指数的影响

脑电双频指数 (ｂｉｓｐｅｃｔｒａｌｉｎｄｅｘ ,ＢＩＳ)可反映脑皮层功能。本研究旨在探讨ＢＩＳ在吸入麻醉中作为一种反映麻醉深度指标的临床价值。资料与方法一般资料　 6 0例择期行开颅手术患者 ,ＡＳＡⅠ～Ⅱ级 ,年龄 2 0～ 6 0岁 ,神志清楚 ,无颅内高压表现 ,无病灶累及ＢＩＳ记录侧额叶的影象学表现。随机分成三组 :安氟醚组(Ｅｎｆ)、异氟醚组 (Ｉｓｏ)和地氟醚组 (Ｄｅｓ) ,每组 2 0例。三组在年龄、性别、体重及身高方面无统计学差异 (表 1)。表 1　病人一般资料 ( ｘ±ｓ)性别 (男 /女 )年龄 (岁 )体重 (ｋｇ) 身高 (ｃｍ)安氟…     

新型吸入麻醉药对肝功能的影响

新型吸入麻醉药地氟醚、七氟醚在９０年代初用于临床，在我国至今未推广应用。本文就该类药物在肝脏的特点。对肝血流、肝功能肝氧供需平衡的影响等作一介绍，对期对临床使用有所帮助。     

吸入麻醉药对心肌收缩力的抑制作用

常用的吸入麻醉药,如氟烷、安氟醚、异氟醚与七氟醚等,在产生全麻作用的同时,也降低了心肌的收缩力。导致这种负性肌力作用的因素有很多。近年来,对其作用机制的研究越来越深入,提出了一些新的观点,现就此予以综述。     

七氟醚用于小儿吸入全麻诱导的临床观察

七氟醚较异氟醚、地氟醚等吸人麻醉药诱导迅速、苏醒快、麻醉效能强,适用于小儿患者的麻醉诱导。本文报道我科2005年1月至2006年10月使用国产七氟醚所观察的38例患儿的资料。     

吸入麻醉药对兔肾交感神经活动的影响

目的比较吸入麻醉药对交感神经活动和血液动力学的影响。方法18只兔被随机分为三组:安氟醚组、异氟醚组和地氟醚组。兔麻醉、肌松和人工通气后,暴露肾交感神经并记录其电生理活动。分别吸入呼气末浓度为0.8%、1.6%、2.4%、3.2%安氟醚,0.6%、1.2%、1.8%、2.4%异氟醚,或3.0%、6.0%、9.0%、12.0%地氟醚。结果交感神经活动在兔吸入2.4%安氟醚、0.6%异氟醚和6.0%地氟醚时分别增加到44%、36%和32%,当进一步增加吸入麻醉药的浓度则抑制肾交感神经活动。血压随着吸入麻醉药浓度的增加不断下降而心率除了2.4%异氟醚诱发心率减慢外无明显变化。结论安氟醚、异氟醚和地氟醚具有双向作用,低浓度兴奋交感神经,高浓度抑制交感神经活动和降低血压。     

闭环靶控吸入麻醉用於肥胖病人的临床研究

目的：观察脑电双频谱指数（BIS）反馈调控异氟醚吸入麻醉用於肥胖病人的可行性．方法：选择40例肥胖择期手术病人，随机分为对照组（Ⅰ组）和BIS反镇组Ⅱ组），每组20例。工组根据MAP和HR以及病人对手术刺激的反应，作为调节麻醉深度的依据．Ⅱ组采用“吸入麻醉执行者”以比例-积分-微分（PID）控制运算法，对目标BIS值与实测值进行处理，调节异氟醚输注泵注入闭式呼吸环路的量，以控制麻醉深度。两组病人均在入室后、诱导期、插管前、插管后、切皮、术中及停吸异氟醚后的意识恢复时间，随访术中是否知晓。结果：麻醉诱导后两组病人的BIS值较基础值明显降低（P〈0．01），术中两组病人的BIS值无显着性差异（P〉0.05）。两组BIS高于60的发生率分别为14．03％和7．48％，具有显着性差异（P〈0．05）．两组BIS低于40的发生率分别为1．75％和1．21％，无显着性差异。术毕唤醒时间以Ⅱ组早于工组（P〈0.05）．术后随访病人均无术中知晓．结论：应用BIS值反镇调控吸入麻醉用於肥胖病人是可行的．     

吸入麻醉药与一氧化氮合用对呼吸功能及肺表面活性物质影响的研究

目的观察异氟醚、七氟醚与吸入一氧化氮(NO)联合应用对机体的呼吸功能、肺表面活性物质(PS)的活性以及循环的影响。方法将36头幼猪随机分为六组，I组为机械通气组(对照组)，11组为NO吸入组．Ⅲ组为异氟醚吸入组．Ⅳ组为异氟醚 NO吸入组，V组为七氟醚吸入组．Ⅵ组为七氟醚 NO吸入组。记录各时点呼吸功能参数和循环指标变化，并对肺泡灌洗液作生化测定。结果Ⅲ、Ⅳ、Ⅴ与Ⅵ组的PS活性较Ⅰ组下降．上述四组通气结束时点呼吸系统总顺应性(Crs)较同组基础时点下降，而Ⅱ组PS活性较Ⅰ组无显著变化，通气结束时呼吸功能较基础时点无显著变化。结论吸入麻醉药对呼吸功能和PS活性具有抑制作用．而吸入NO本身对其无抑制作用，两者合用并未加重吸入麻醉药对呼吸功能和PS影响。     

挥发性吸入麻醉药对肺的作用

挥发性吸入麻醉药对肺的作用目前尚未有定论，其中有较多争议之处。不同种类、不同吸入浓度以及不同生理条件下的吸入麻醉药对肺的作用不同，可以引起肺的损伤作用、导致肺内分流增加，也可以产生肺的缺血／再灌注损伤的保护作用，其机制尚未完全清楚。     

新疆维吾尔族、汉族人群体重指数、身体脂肪组织、非脂肪组织、骨矿物质含量的差异性研究

目的 通过对维吾尔族、汉族不同民族人群BMI、Bone、Fat及Lean的测定比较,了解新疆维、汉两族人群 Bone、Fat、Lean的分布特征,BMI的流行趋势以及有无明显的种族差异.探讨BMI与Bone、Fat及Lean之间的变化规律.方法 利用双能X线骨密度仪(DMS LEXXOS外星人)全身身体成分分析软件,对新疆维吾尔族、汉族人群的BMI以及3个测量指数(Bone、Lean、Fat)进行分析和多元回归分析.结果 无论男女或任何年龄段维吾尔族超重者均多于汉族人群;这与此前多篇相关报道一致[1-3].在同等BMI条件下,汉族男、女性Bone、Lean的百分比均大于维族男、女性.而维族男、女性Fat的百分比均大于汉族男、女性.维、汉人群的身体构建差异不大;从遗传理论的角度来说应该有一定的影响,但是经过近几十年各族人民在文化、饮食等方面的交流,后天因素有了很大的发展空间.结论 新疆维、汉族人群的膳食结构不平衡和身体活动不足是导致超重和肥胖率上升的最主要的原因,也是影响新疆汉族人群与维吾尔族人群身体健康的主要因素.     

体质指数和体脂百分比与类风湿关节炎继发骨质疏松的相关性研究

目的探讨体质指数(BMI)和体脂百分比(PBF)与类风湿关节炎(RA)继发骨质疏松(OP)间的相关性。方法采用生物电阻抗体成分测定法测量359例RA患者和158例年龄、性别相匹配的正常对照组体重(kg)、身高(m)和PBF,根据体重/(身高)2计算出BMI,并将BMI分为4组:消瘦BMI18.5,正常24BMI≥18.5,超重28BMI≥24,肥胖BMI≥28;PBF分为2组:肥胖为PBF男25%或女30%,否则为正常。采用双能X线骨密度吸收仪测定髋部(包括股骨颈Neck、Ward三角区、大转子GT、总髋部Hip)及腰椎1-4(L1-4)骨密度(BMD)。结果 RA患者BMI低于正常对照组(22.40±3.76 vs 23.66±3.24,t=3.813,P0.0001),其中消瘦患者百分比明显高于对照组(14.4%vs 5.8%,x~2=10.536,P=0.015);而PBF则高于对照组(32.45±10.38 vs 30.53±6.98,t=2.442,P=0.015)。RA患者OP发生率为37.9%(128/338),明显高于对照组的13.9%(22/158)(x~2=29.265,P0.0001)。RA患者不同BMI分组间各部位BMD均有显著不同,且都表现为消瘦组水平更低,超重或肥胖组水平更高(P0.0001～0.05);除Ward区的PBF正常组BMD高于肥胖组(t=2.224,P=0.027)外,其余各部位BMD均无明显差别(P0.05)。Hip区和L1-4区均表现为消瘦组OP发生率(27.8%、20.7%)明显高于肥胖组(3.7%、1.1%)(x~2=22.041,P=0.001;x~2=13.401,P=0.037)。不同PBF分组间骨量构成比的比较无差别(P0.05)。各部位BMD均与BMI成正直线相关(P0.0001～0.01);而Ward、GT、Hip区BMD与PBF成负直线相关(P=0.015～0.04)。多元Logistic回归分析结果显示:年龄(OR=1.114,95%CI:1.082～1.148,P0.0001)、性别(OR=5.802,95%CI:2.608～12.906,P0.0001)和病程(OR=1.050,95%CI:1.017～1.084,P=0.003)均为RA患者发生OP的危险因素,而BMI(OR=0.879,95%CI:0.815～0.946,P=0.001)为发生OP的保护因素。结论 BMI和PBF在RA中变化不同,且呈现出与BMD相反的相关性,BMI是RA患者发生OP的保护因素。     

Body mass index,body fat percentage,and the effect of body fat mass on SWL success

Objectives In the present study, we investigated the effects of the Body Mass Index (BMI), the Body Fat Percentage (BFP), and the Body Fat Mass (BFM) on success of SWL, prospectively. Patients and methods The BMI, BFP, BFM values of patients, who were treated by SWL due to upper urinary system stone disease (pelvis renalis, upper ureter, kidney lower and upper calices) between January and December 2005 in our hospital’s urolithiasis center, were measured. Patients with stones smaller than 5 mm or larger than 20 mm and patients who had a stone localized somewhere other than in the upper urinary system, were not included in the study. Patients evaluated to be clinically successful according to the SWL were put in group 1, and the other patients who were not successful were included in group 2. Results About 158 (97 male, 61 female) patients aged between 16 and 92 (mean 36.69 (±13.22) years), put on SWL therapy due to presence of upper urinary system stone disease, were included in the study. While the mean BMI was 23.97 ± 0.4 in group 1 and 25.98 ± 0.5 (P = 0.02) in group 2, BFP was 23.85 ± 0.8 in group 1 and 29.19 ± 1.1 (P = 0.001) in group 2, and BFM was determined to be 16.74 ± 0.7 and 21.19 ± 1.01 (P = 0.001) in group 2. Regarding all the parameters (BMI, BFP, BFM), the statistical analyses carried out between the groups showed significant differences. Conclusion BFP and BFM parameters are also important factors along with the BMI in providing a successful SWL treatment. All the parameters should be considered regarding the success of the treatment and the patients should be informed.     

Mutagenicity of inhaled anesthetics in Drosophila melanogaster

The mutagenic effects of several inhaled anesthetic agents were investigated using the sex-linked recessive lethal assay in the fruit fly, Drosophila melanogaster. Male wild-type flies were exposed for 1 hr to either halothane, enflurane, isoflurane, or fluroxene at vapor concentrations of 1 or 2% or to nitrous oxide at concentrations of 40 or 80%. Control flies were exposed to air alone. Following treatment, male flies were mated with untreated virgin females of the Basc strain and the rate of sex-linked recessive lethals was determined in the F2 generation. Halothane and fluroxene produced a dose-dependent and statistically significant increase in the rate of sex-linked recessive lethals, whereas enflurane, isoflurane, and nitrous oxide were not mutagenic at the concentrations tested.     

Age affects the pharmacokinetics of inhaled anesthetics in humans.

To define the effect of aging on the pharmacokinetics of volatile anesthetics, we determined the end-tidal and mixed expired anesthetic concentrations of isoflurane, enflurane, halothane, and methoxyflurane during 30 min of simultaneous administration and for 5-12 days of elimination in seven healthy young patients (31 +/- 1.8 yr [mean +/- SEM]) and in 11 healthy aged patients (73.2 +/- 3.1 yr [mean +/- SEM]). A five-compartment mammillary function was fit to the end-tidal and mixed expired anesthetic elimination data simultaneously using ordinary least-squares analysis. We assumed the compartments to represent the following tissue groups: lungs and pulmonary capillary blood (V1), vessel-rich tissues (i.e., liver, heart, kidneys, and brain) muscle, an unidentified fourth compartment, perhaps fat adjacent to well-perfused tissues, and fat tissues. The tissue volumes and perfusions estimated for these compartments approximated values from the literature. In general, the volume of the fourth and fifth compartments increased with age, and perfusion to the second and fifth compartments decreased with age. Aging delayed anesthetic elimination and increased the apparent volume of distribution at steady state. These observations are compatible with decreased tissue perfusion and an increase in the ratio of fat/lean body weight in the elderly. Our mammillary analysis described the behavior of less soluble anesthetics such as isoflurane well, but that of highly soluble anesthetics such as methoxyflurane less well.     

A hypothesis on the origin and evolution of the response to inhaled anesthetics

In this article, I present an evolutionary explanation for why organisms respond to inhaled anesthetics. It is conjectured that organisms today respond to inhaled anesthetics owing to the sensitivity of ion channels to inhaled anesthetics, which in turn has arisen by common descent from ancestral, anesthetic-sensitive ion channels in one-celled organisms (i.e., that the response to anesthetics did not arise as an adaptation of the nervous system, but rather of ion channels that preceded the origin of multicellularity). This sensitivity may have been refined by continuing selection at synapses in multicellular organisms. In particular, it is hypothesized that 1) the beneficial trait that was selected for in one-celled organisms was the coordinated response of ion channels to compounds that were present in the environment, which influenced the conformational equilibrium of ion channels; 2) this coordinated response prevented the deleterious consequences of entry of positive charges into the cell, thereby increasing the fitness of the organism; and 3) these compounds (which may have included organic anions, cations, and zwitterions as well as uncharged compounds) mimicked inhaled anesthetics in that they were interfacially active, and modulated ion channel function by altering bilayer properties coupled to channel function. The proposed hypothesis is consistent with known properties of inhaled anesthetics. In addition, it leads to testable experimental predictions of nonvolatile compounds having anesthetic-like modulatory effects on ion channels and in animals, including endogenous compounds that may modulate ion channel function in health and disease. The latter included metabolites that are increased in some types of end-stage organ failure, and genetic metabolic diseases. Several of these predictions have been tested and proved to be correct.