异氟烷麻醉下不同CO_2气腹压对小型猪呼吸系统的影响

选取16头健康小型猪随机分为A、B、C、D 4组,分别以0 mm Hg、10 mm Hg、12 mm Hg、15 mm Hg的气腹压进行充气腹试验,通过监测脉搏血氧饱和度、呼吸末二氧化碳分压及气道峰压来探讨不同CO_2气腹压力对小型猪呼吸系统的影响。结果显示,A组试验猪脉搏血氧饱和度、呼吸末二氧化碳分压及气道峰压均保持平稳,B、C、D组试验猪脉搏血氧饱和度呈下降趋势,呼吸末二氧化碳分压及气道峰压呈上升趋势。本试验确定了不同CO_2气腹压对小型猪呼吸系统的影响程度是D组C组B组。表明在小型猪长时间腹腔镜手术充气腹时,为获得足够术野和操作空间的同时,应尽量降低气腹本身对机体呼吸系统的影响,选用10~12 mm Hg的气腹压值为宜,不应超过15 mm Hg。     

不同CO2气腹压对小型猪循环系统的影响

选择30只健康小型猪随机分为A、B、C、D、E等5组。分别以0、0．8、1．06、1．33、1．6kPa的气腹压进行充气腹试验,以探讨不同CO2气腹压对小型猪循环系统的影响。结果显示,A组试验猪血压和心率持续降低。B、C、D、E组试验猪会引起血压和心率的升高。本试验确定了不同气腹压对小型猪循环系统的影响程度是E组〉D组〉C组〉B组。因此,在小型猪腹腔镜手术充气腹时,选用1.33kPa气腹压值对循环系统的影响较小,同时能保证小型猪腹腔的充分膨胀隆起,便于手术操作,从而为今后开展小型猪腹腔镜手术奠定了理论基础。     

不同CO_2气腹压对小型猪心肌酶谱的影响

选择24只健康小型猪随机分为A、B、C、D 4组。分别用0.8 kPa、1.06 kPa、1.33 kPa和1.6 kPa的气腹压进行充气腹试验,以探讨不同CO_2气腹压对小型猪心肌酶谱的影响。结果表明,CO_2气腹压可引起LDH、CK、CK-MB升高;D组心肌酶谱的变化与A组相比差异显著。C组(1.33 kPa)是进行小型猪腹腔镜手术的最佳气腹压值,将气腹压设定为1.33 kPa为宜。     

CO_2气腹压对小型猪氧化应激水平和神经内分泌激素的影响

本试验在前期小型猪最佳气腹压筛选工作的基础上,进一步探讨最佳气腹压对小型猪氧化应激水平和神经内分泌激素的影响。通过测定气腹过程中各时期血液中T-SOD、GSH-Px、MDA、ACTH、COR和CA的含量,表明1.33kPa气腹压对小型猪氧化应激水平和神经内分泌激素无明显的损伤性改变。从理论上证明1.33kPa气腹压可以安全的应用于小型猪腹腔镜手术。     

不同CO2气腹压对山羊肝、肾功能的影响

选择21只健康山羊随机均分为A、B、C 3组。分别用1.33、2.0、2.4kPa的气腹压值进行充气腹试验,以探讨不同CO2气腹压对山羊肝、肾功能的影响。结果表明:CO2气腹压可引起ALT、AST、ALP、Tbil、Crea升高和U-rea降低;在放气后1或2、3 d时,B、C 2组与A组相比较对肝、肾功能的影响差异显著;在放气后4d,A组肝、肾功能基本能恢复到气腹前水平,B、C 2组放气后4d尚未恢复到气腹前水平。当气腹压≥1.06 kPa时,均能够保证山羊的腹腔充分膨胀隆起。本试验确定了在山羊腹腔镜手术充气腹时,应选用1.06kPa≤PP≤1.33kPa气腹压值为宜,从而为今后开展山羊腹腔镜手术奠定了理论基础。     

复合麻醉剂对小型猪循环和呼吸系统的影响

观察了复合麻醉剂(XFM)对小型猪循环和呼吸系统的影响.结果得出:注射XFM后,小型猪的血压及心率5~10 min时升至最高,之后逐渐下降,在80~100 min时降至最低;体温从注药后开始下降,在整个监测过程中体温下降幅度在2℃以内;动脉血氧饱和度在整个监测过程中都在90%以上;呼吸频率在5~10 min及80 min时出现显著的变化.综合分析后表明:XFM对小型猪呼吸、循环系统的影响短暂且轻微,证明XFM组方科学、合理、临床使用安全.     

异氟烷联用速眠新Ⅱ对西藏小型猪麻醉效果的观察

为了获得对西藏小型猪安全、高效、稳定的麻醉效果,创造良好的外科手术环境,试验采用肌肉注射速眠新Ⅱ(0.1 mL/kg)行诱导麻醉和吸入异氟烷行维持麻醉的联合麻醉方法对10头行氩氦刀冷冻术的西藏小型猪进行麻醉,观察以速眠新Ⅱ作为诱导麻醉对西藏小型猪的麻醉效果以及异氟烷在手术过程中的使用量、镇痛效果、呼吸频率和心率变化及术后苏醒情况。结果表明:速眠新Ⅱ应用于西藏小型猪可达到诱导麻醉的预期效果,手术过程中异氟烷平均吸入浓度为1.78%,西藏小型猪平均心率为69次/min,平均呼吸频率为19次/min,氧饱和度范围值是95%～100%,麻醉过程中未出现麻醉死亡。说明异氟烷联用速眠新Ⅱ是一种较理想的麻醉方法,可应用于长时间的手术过程。     

3种复合麻醉剂对小型猪循环、呼吸指标的影响

为了比较3种常用复合麻醉剂对小型猪循环、呼吸影响,将中国实验用小型猪分成3组进行比较.第1组肌肉注射小型猪复合麻醉剂(XFM)0.15 mL/kg体重;第2组联合肌肉注射氯胺酮8 mg/kg体重、安定1 mg/kg体重;第3组联合肌肉注射速眠新Ⅱ0.1 mL/kg体重、戊巴比妥钠10.5 mg/kg体重.试验结果表明,氯胺酮和速眠新Ⅱ对小型猪麻醉后的循环、呼吸系统有一定的抑制作用,尤其使用速眠新Ⅱ进行麻醉的小型猪血氧饱和度(SpO2)下降明显.XFM麻醉后小型猪循环、呼吸系统无明显影响,SpO2、血压(BP)以及呼吸系统各指标均在生理正常范围内,比较之下更适合用于小型猪的麻醉.     

小型猪特异性麻醉颉颃剂对小型猪血浆RAAS的影响

为了研究小型猪特异性麻醉拮抗剂对小型猪血浆肾素-血管紧张素-醛固酮系统(RAAS)的影响,将14头中国实验用小型猪,随机分为单纯麻醉组(X/S组)和麻醉-催醒组(X/W组),肌肉注射小型猪特异性麻醉剂(XFM),记录麻醉前及麻醉后5 min、10 min、20 min、30 min无创血压和心率(HR);麻醉后30 min即刻,麻醉-催醒组肌肉注射小型猪特异性麻醉颉颉抗剂,单纯麻醉组肌肉注射相同量的生理盐水,并记录麻醉后32 min、35 min、40 min、60 min、90 min、120 min小型猪的无创血压及心率(HR),并于以上时间点采取前腔静脉血样。采用ELISA方法测定小型猪血浆中RAAS含量,并分析它们与心率和血压之间的相关性。结果显示,与对照组相比,在肌肉注射小型猪特异性麻醉颉颃剂后,无创血压、HR均明显的升高(P<0.01或P<0.05);小型猪血浆血管紧张素(AⅡ)浓度发生明显变化(P<0.05);血浆AⅡ的浓度与HR呈现显著负相关(P<0.05)。表明血浆中R-A-A-S参与了小型猪血流动力学变化的调节。     

不同二氧化碳气腹压对犬呼吸系统的影响

充气腹是进行腹腔镜手术操作时必要步骤之一。用于充气腹的气体种类比较多,如笑气、氦气、空气等是临床上曾经采用过的气体,众多学者对以[1]     

Use of end-tidal partial pressure of carbon dioxide to predict arterial partial pressure of carbon dioxide in harp seals during isoflurane-induced anesthesia

OBJECTIVE: To evaluate the relationship between end-tidal partial pressure of CO(2) (ETCO(2)) and PaCO(2) in isoflurane-anesthetized harp seals. ANIMALS: Three 5-month-old 25- to 47-kg harp seals (Phoca groenlandica). PROCEDURES: PaCO(2) was determined in serial arterial samples from isoflurane-anesthetized seals and compared with concomitant ETCO(2) measured with a side-stream microstream capnograph. Twenty-four paired samples were subjected to linear regression analysis and the Bland-Altman method for assessment of clinical suitability of the 2 methods (ie, PaCO(2) and ETCO(2) determinations). The influence of ventilation rate per minute (VR) on the ETCO(2) to PaCO(2) difference (P[ET-a] CO(2)) was examined graphically. RESULTS: The correlation coefficient between the 2 measurements was 0.94. The level of agreement between ETCO(2) and PaCO(2) varied considerably. Values of ETCO(2) obtained with a VR of < 5 underestimated PaCO(2) to a greater degree (mean bias, -4.01 mm Hg) and had wider limits of agreement of -13.10 to 5.07 mm Hg (-4.01 mm Hg +/- 1.96 SD), compared with a VR of > or = 5 (mean bias, -2.24 mm Hg; limits of agreement, -7.79 to 3.30 mm Hg). CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that a microstream sidestream capnograph provides a noninvasive, sufficiently accurate estimation of PaCO(2) with intermittent positive ventilation at a VR > or = 5 in anesthetized harp seals.     

乳化异氟醚全凭静脉麻醉对大鼠海马钙调蛋白信号转导系统的影响

旨在探讨海马中钙调蛋白信号转导系统在大鼠乳化异氟醚静脉麻醉过程中的调控作用和变化规律,将24只大鼠分为对照组、浅麻醉组、深麻醉组和苏醒组。采集各组大鼠海马组织,经RT-PCR检测海马样品中钙调蛋白(CaM)、钙调蛋白依赖性蛋白激酶Ⅱ(CaMKⅡ)和钙调神经磷酸酶(CaN)的mRNA表达水平。结果显示:浅麻醉组大鼠海马CaM、CaMKⅡ和CaN mRNA表达水平较对照组显著降低(P0.05),深麻醉组3种mRNA表达水平较对照组极显著降低(P0.01),苏醒期3种mRNA表达水平与对照组无显著差异(P0.05)。结果表明,乳化异氟醚抑制了海马CaM、CaMKⅡ和CaN mRNA表达,海马钙调蛋白信号转导系统参与了乳化异氟醚麻醉调控过程,本试验为揭示乳化异氟醚麻醉机理提供了新的研究方向。     

Effects of metaraminol bitartrate on intraocular pressure in dogs under halothane anesthesia

The effects of metaraminol bitartrate on intraocular pressure (IOP) were studied in dogs anesthetized with halothane. Forty-five healthy, adult, mixed-breed dogs, of both sexes, were divided into three groups of 15 dogs each (GI, GII and GIII) and maintained under general anesthesia with halothane after tranquilization with levomepromazine and induction with thiopental. Saline (0.9%) was administered intravenously (IV) to GI through continuous infusion, at a velocity of 0.125 mL kg⁻¹ min⁻¹. GII and GIII received metaraminol 0.004% IV, at a dose of 5 μg kg⁻¹ min⁻¹, at 0.125 mL kg⁻¹ min⁻¹ and at a dose of 2 μg kg⁻¹ min⁻¹, at 0.06 mL kg⁻¹ min⁻¹, respectively. IOP was measured by applanation tonometry (Tono-Pen) before and during anesthesia. Results showed that IOP decreased in GI, increased in GII, and remained at basal levels in GIII. Continuous infusion of metaraminol at 2 μg kg min⁻¹ maintained IOP at pretest levels, while infusion at 5 μg kg⁻¹ min⁻¹ produced an elevation of IOP.     

高浓度CO2对热胁迫条件下高羊茅生长和抗氧化系统的影响

大气CO₂浓度及温度逐年上升是当前全球范围内主要的两大气候特征,但不断升高的大气CO₂浓度可以缓解高温对植物生长发育带来的负面影响。为了探究高浓度CO₂在多年生禾草生长和抗氧化系统方面对热胁迫的响应,本试验以高羊茅(Festuca arundinacea cv. ‘Barlexas’)为材料,进行CO₂[当前浓度(400 μmol/mol)和高浓度(800 μmol/mol)]和温度[(最适生长温度(25/20 ℃)和热胁迫温度(35/30 ℃)]处理。结果表明,高温导致高羊茅的生长速率(G_r)、净光合速率(P_n)、光化学效率(F_v/F_m)、绿叶数、活性氧清除物质[超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)]活性等显著下降,叶片黄绿比、电解质渗漏率(EL)、丙二醛(MDA)、活性氧[过氧化氢(H₂O₂)、超氧阴离子(O₂^-·)]显著上升;热胁迫处理28 d时,高浓度CO₂较正常CO₂浓度使细胞膜稳定性增强(EL、MDA分别降低72%和39%),光合能力提高(P_n、F_v/F_m、绿叶数分别升高174%、17%和165%),活性氧积累减少(H₂O₂、O₂^-·含量分别下降46%和31%)。以上结果说明:高浓度CO₂通过提高高羊茅在热胁迫下的光合能力,维持细胞膜的稳定以及减少体内活性氧的积累减弱了热胁迫对植株的伤害,从而提高了高羊茅的抗热性。     

Inhaled carbon monoxide concentration during halothane or isoflurane anesthesia in horses

OBJECTIVE: The purpose of this study was to assess carbon monoxide (CO) exposure during equine anesthesia with either halothane (H) or isoflurane (I) delivered in a circle rebreathing system. STUDY DESIGN: Prospective clinical investigation. ANIMALS: Fifty client-owned horses. METHODS: Horses were randomly assigned for anesthetic maintenance with H (n = 26) or I (n = 24). Two large animal anesthetic machines were used and assigned to a single agent for 2-4 weeks at a time. Machines were disassembled and soda lime changed prior to switching anesthetic agents. Inhalant anesthetic concentration and CO concentration were measured in gas samples obtained from the inspiratory limb of the anesthetic circuit. Values were recorded at 15 minute intervals for 90 minutes. Soda lime status (new or used) and mode of ventilation (spontaneous or mechanical) were also recorded. Data were analyzed using a five-factor ANCOVA with repeated measures. RESULTS: Inspired CO concentration for H and I increased from 1 +/- 3 and 6 +/- 11 ppm at baseline to 54 +/- 33 and 21 +/- 18 ppm at 90 min, respectively (mean +/- sd). H was associated with significantly greater CO concentrations than I at 30 to 90 min, although baseline CO was significantly greater in the I group than the H group. Oxygen flow rates were 9.9 +/- 0.5 L/min at baseline for H and I, and 5.0 +/- 0.4 and 5.0 +/- 0.7 L/min at 90 min for H and I, respectively. There were no significant differences between groups for O2 flow at any time point. Neither mechanical ventilation nor new versus used soda lime affected CO concentration. CONCLUSIONS: Significantly higher concentrations of CO were recorded during the administration of H than I. CLINICAL RELEVANCE: Levels of CO observed during the administration of either H or I for 90 minutes to horses were not clinically significant.     

Effects of hypercapnic hyperpnea on recovery from isoflurane or sevoflurane anesthesia in horses

Objective To test the hypothesis that hypercapnic hyperpnea produced using endotracheal insufflation with 5–10% CO₂ in oxygen could be used to shorten anesthetic recovery time in horses, and that recovery from sevoflurane would be faster than from isoflurane. Study design Randomized crossover study design. Animals Eight healthy adult horses. Methods After 2 hours’ administration of constant 1.2 times MAC isoflurane or sevoflurane, horses were disconnected from the anesthetic circuit and administered 0, 5, or 10% CO₂ in balance O₂ via endotracheal tube insufflation. End‐tidal gas samples were collected to measure anesthetic washout kinetics, and arterial and venous blood samples were collected to measure respiratory gas partial pressures. Horses recovered in padded stalls without assistance, and each recovery was videotaped and evaluated by reviewers who were blinded to the anesthetic agent and insufflation treatment used. Results Compared to isoflurane, sevoflurane caused greater hypoventilation and was associated with longer times until standing recovery. CO₂ insufflation significantly decreased anesthetic recovery time compared to insufflation with O₂ alone without significantly increasing PaCO₂. Pharmacokinetic parameters during recovery from isoflurane with CO₂ insufflation were statistically indistinguishable from sevoflurane recovery without CO₂. Neither anesthetic agent nor insufflation treatment affected recovery quality from anesthesia. Conclusions and clinical relevance Hypercapnic hyperpnea decreases time to standing without influencing anesthetic recovery quality. Although the lower blood gas solubility of sevoflurane should favor a shorter recovery time compared to isoflurane, this advantage is negated by the greater respiratory depression from sevoflurane in horses.