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101.
目的 探讨咪唑安定、芬太尼、丙泊酚联用对老龄大鼠认知功能的影响以及这种影响是否与海马tau蛋白磷酸化水平有关.方法 雄性18月龄SD大鼠40只,随机分成全麻组和对照组,每组20只.每组分别于处理后第1和第7天各断头处死10只,HE染色光镜下观察海马神经元结构,免疫组化染色法检测海马tall蛋白Thr231和Ser404位点磷酸化蛋白的表达水平.其中后处死大鼠于处理后第1周行水迷宫实验.结果 处理后第1天,全麻组大鼠寻找平台的时间明显长于对照组(P<0.01),但第2~7天与对照组比较差异无统计学意义.处理后第1天,全麻组海马tau蛋白Thr231位点的磷酸化水平高于对照组(P<0.05).第7天,两组Thr231、Ser404位点的磷酸化水平差异无统计学意义.光镜下各组大鼠海马神经元结构未见明显异常.结论 咪唑安定、芬太尼、丙泊酚联用可引起老龄大鼠麻醉后第1天出现短暂的认知功能减退,海马tau蛋白Thr231位点的过度磷酸化可能与其有关.  相似文献   
102.
小儿腹腔镜下疝囊高位结扎术的麻醉处理   总被引:1,自引:1,他引:0  
目的探讨小儿腹腔镜下疝囊高位结扎术的麻醉处理方法和安全性。方法本组80例腹腔镜下疝囊高位结扎术患儿,ASAⅠ~Ⅱ级,以气管全麻下行术式,入室后连续监测HR、MAP、SpO2、气道峰压(PIP)、PETCO2及体温,并分别记录术前、气腹后5min、气腹后10min、放气后10min的各项监测指标。结果所有患儿麻醉均满意,无一例出现麻醉意外、并发症,CO2气腹后10、20min HR、MAP、PETCO2、PIP显著升高(p<0.05,p<0.01),SpO2无显著变化,放气后10min各项指标与术前相比差异无显著意义。结论面对小儿特殊的解剖、生理和CO2气腹对生理产生的影响,做好术前准备,选择正确的麻醉方法和合适的麻醉药物,维持稳定的循环,小儿可安全实施腹腔镜疝囊高位结扎手术。  相似文献   
103.
高龄患者后腹腔镜手术的麻醉管理   总被引:1,自引:0,他引:1  
目的总结伴发全身性疾病的高龄患者后腹腔镜手术麻醉管理的经验。方法回顾性分析2002年10月-2007年1月81例高龄患者(年龄70-86岁,平均74.2岁)后腹腔镜的临床资料,其中有全身性伴发疾病77例,81例手术均在全麻下完成。结果气腹后35例(43.2%)发生高碳酸血症,35例(43.2%)发生酸中毒;41例(50.6%)出现不同程度的高血压。66例(81.5%)在手术室内拔除气管导管,手术结束至手术室内拔除气管插管时间5-50 min,平均15.1 min;1例(1.2%)带气管插管回本病房;14例(17.3%)术后转入ICU。1例(1.2%)术后第3天并发急性心肌梗死死亡。1例术后发生严重谵妄状态。结论高龄患者可耐受后腹腔镜手术高碳酸血症、酸中毒以及气腹后血压升高的风险,但围麻醉期的处理须谨慎。  相似文献   
104.
Study Objective: To compare the volatile anesthetic sevoflurane with halothane, enfurane, and isof urane on the uptake and biotransformation in humans.

Design: Prospective pharmacokinetic study of sevofurane administration in human subjects.

Setting: Inpatient surgery clinic at a university medical center.

Patients: Thirty-two Japanese patients, free of systemic diseases, undergoing minor elective surgery with endotracheal general anesthesia.

Interventions: The patients were assigned randomly to one of four groups: halothane, enflurane, isofurane, or sevofurane. One of the four volatile anesthetics being investigated [equivalent to 1.1 minimum alveolar concentration (MAC): halothane, 0.85%; enfurane, 1.85%; isofurane, 1.27%; and sevofurane, 1.88%; in inspired concentrations throughout the first hour of anesthesia] was administered for 60 minutes.

Measurements and Main Results: In all patients, serum and urinary fluoride concentrations were measured. The concentrations of all gases were measured separately with a mass spectrometer. The cumulative uptake of each anesthetic agent during a certain period was calculated as an integration of the uptake rate per minute. The results for one-hour inhalation of sevofurane (1.1 MAC) showed an uptake (corrected for body surface area and MAC) of 490 ml/m2/MAC and estimated degradation rate of 3.3%. For purposes of comparison, similar studies of halothane (uptake, 653 ml/m2/MAC; degradation rate 15.7%), enfurane (1150 ml/m2/MAC; 1.3%), and isofurane (439 ml/m2/MAC; 0.6%) were also conducted. Sevofurane had a peak serum inorganic fluoride concentration of 19.3 μmol/L, and no abnormality in hepatic or renal functions was observed in any of the subjects during the two weeks postoperatively.

Conclusions: Accurate determinations of uptake and degradation rate for sevoflurane and three other volatile anesthetics in Japanese patients were obtained. These findings have established that, despite its relatively large MAC *1.71%), sevoflurane has a small uptake due to its low solubility. However, the degradation rade was shown to be as high as 3.3%, resulting in a higher serum fluoride concentration than seen after administration of isoflurane, halothane, and (possibly) enflurane.  相似文献   

105.
The effects of anesthesia on otoacoustic emissions   总被引:4,自引:0,他引:4  
We have measured transient-evoked and distortion-product otoacoustic emissions (OAEs) in the chinchilla and compared them in the awake and anesthetized animal (using either ketamine or barbiturate agents). We report a significant increase in OAE amplitudes during anesthesia, particularly using ketamine. These effects are most evident for transient-evoked otoacoustic emissions (TEOAEs) as measured in the non-linear mode. Our data support the hypothesis that tonic activity levels in cochlear efferents may be reduced by anesthetic effects, either directly or indirectly (e.g., by general reductions in descending pathway activity), and that reduced cochlear efferent activity will result in the observed increase of OAE amplitudes.  相似文献   
106.
Anesthetic techniques for day surgery must foresee a prompt recovery of alertness, ambulation and alimentation. The aim of our study is to evaluate mivacurium chloride in outpatient general anesthesia. Twenty patients, aged 18–55 years, American Society of Anesthesiologists (ASA) class I–II, undergoing surgical procedures were studied. Mivacurium (0.2 mg/kg) was administered to provide neuromuscular relaxation and endotracheal intubation was performed. Additional doses of 0.1 mg/kg mivacurium were given to maintain neuromuscular block, monitored by Relaxograph (Datex). In all patients, mivacurium provided satisfactory conditions for tracheal intubation after a mean time of 120 ± 15 s. Spontaneous recovery after the last dose of mivacurium was obtained in a mean time of 15 min. No side-effects or significant hemodynamic changes were recorded. The incidence of histamine-related side-effects was low. Mivacurium produces spontaneous recovery of neuromuscular block in a short time and shows some ideal properties for anesthesia in day surgery.  相似文献   
107.
Background: The prevalence of respiratory diseases in smokers and nonsmokers and the incidence of perioperative respiratory events (PREs) were investigated for patients undergoing general anaesthesia. The aim was to quantify well-known problems and to identify possible new associations between smoking and PREs.
Methods: From July 1992 to December 1994, risk factors, demographic data, and PREs were documented by an automatically readable anaesthetic record (ARAR). PREs were used as defined by the German Society of Anaesthesiology and Intensive Care.
Results: Of 26 961 subsequent anaesthesias in adults, 7122 (26.4%) were performed in smokers with a prevalence of chronic bronchitis of 23.3% (4.8% in nonsmokers). 1573 PREs occurred in 1397 (5.2%) of all anaesthetics. 459 events concerned intubation problems and problems in technical airway management. 1114 specific respiratory events (SPREs) like re-intubation, laryngospasm, bronchospasm, aspiration, hy-poventilation/hypoxaemia and others had a total incidence of 5.5% in smokers and 3.1% in nonsmokers. The relative risk (RR) of SPREs was 1.8 in all smokers, 2.3 in young (16–39 years) smokers, and 6.3 in obese young smokers. The RR of perioperative bronchospasm was 25.7 in young smokers with chronic bronchitis.
Conclusion: The impact of smoking on perioperative respiratory problems should make anaesthetists take this widespread preoperative condition seriously, particularly in young adults. The presented method of incident reporting (based on a national classification) could contribute to future research in anaesthetic epidemiology.  相似文献   
108.
目的:观察通气时碱石灰尘埃向呼吸环路中的排放及被呼吸道阻留的情况。方法:麻醉机环路连接集尘袋及筛装新碱石灰。JT库尔特颗粒计数仪动态测定排尘量。其颗粒测量范围为1~125μm3,通气10分后测定呼吸环路加集尘袋内的尘埃量即为总尘量,收取称干重得尘埃分散度。通过对Nar-comed、Drager、Sular808和103麻醉机行上述测量后,另以前者(N机)为例,其环路按相应处理分干燥、湿化和过滤三组,志愿者模拟通气10分测定环路含尘量后与总尘量差得气管肺的阻留量。结果:四种麻醉机环路内碱石灰尘埃的分散度达13mg/m3以上。尘埃排放量与通气时间呈正比(r=0.95,P<0.01)。N机干燥组中总排尘量的半数以上被气管肺阻留。湿化组该阻留量明显下降(P<0.05),而过滤组环路内总排尘量和气管肺阻流量下降更为显著(P<0.01)。结论:使用新碱石灰通气时,麻醉机环路内存在严重的尘埃污染,环路内湿化有一定的防尘作用,但以滤过处理效佳。  相似文献   
109.
异丙酚在无抽搐电休克治疗麻醉中的应用   总被引:3,自引:0,他引:3  
目的 :研究异丙酚在无抽搐电休克治疗 (MECT)麻醉中的应用效果及安全性。方法 :34例首次住院的精神分裂症患者随机分为异丙酚组和硫喷妥钠组 ,每组 17例 ,每例完成 1个疗程 6次MECT治疗 ,每组完成 10 2人次治疗 (n =10 2 )。每次治疗时 ,异丙酚组给予异丙酚静脉麻醉 ,硫喷妥钠组给予硫喷妥钠静脉麻醉 ,全麻诱导后皆静注琥珀酰胆碱 ,待肌肉松弛后行MECT治疗。全程监测患者心电图、血氧饱和度、血压、心率、脉搏 ,并观察记录自主呼吸恢复时间。苏醒时间和不良反应 ,进行前瞻性研究。结果 :与硫喷妥钠组相比 ,异丙酚组自主呼吸恢复快 ,苏醒快 ,无咳嗽 ,呃逆 ,呕吐等不良反应 ,两组差异显著。而异丙酚组注射点疼痛发生率显著高于硫喷妥钠组。结论 :在MECT中应用异丙酚静脉麻醉是一种更安全、有效的方法。  相似文献   
110.
Multiple reports of cauda equina syndrome and transient radicular nerve root irritation have suggested that lidocaine spinal anesthesia may be responsible. In this case report, a patient with a preexisting diabetic neuropathy received a partial block following a tetracaine spinal, which was followed by a lidocaine spinal. Following block resolution, a new conus medullaris syndrome was diagnosed. Because of the close proximity of the cauda equina and the conus medullaris, differentiation between these syndromes can be difficult. The preexisting diabetic neuropathy may have predisposed this patient to neurologic injury. The choice of a different local anesthetic drug with less neurotoxic potential such as bupivacaine may have prevented this injury.  相似文献   
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