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71.
腹部手术患者吸入七氟醚与异氟醚麻醉恢复的比较   总被引:2,自引:0,他引:2  
目的比较腹部手术患者吸入七氟醚与异氟醚麻醉恢复的情况。方法全麻下行开腹手术患者40例,随机分为2组(n=20):七氟醚组(S组)及异氟醚组(Ⅰ组)。麻醉诱导后行气管插管,机械通气。诱导后吸入纯氧,氧流量2 L/min,30min后调整为1 L/min。手术开始前,调整吸入麻醉药的呼气末浓度为1.0 MAC。麻醉维持:吸入七氟醚或异氟醚,间断静脉注射罗库溴铵和芬太尼,维持血压和心率波动幅度不超过基础值30%。缝皮结束时,停止吸入七氟醚或异氟醚,纯氧流量调整为5 L/min。记录睁眼时间(停止吸入麻醉药到睁眼的时间)、拔除气管导管时间(停止吸入麻醉药到拔除气管导管的时间)、Aldrete评分达到9分时间(从停止吸入麻醉药计时)及麻醉后恢复室(PACU)停留时间。记录吸入麻醉药用量。结果与Ⅰ组比较,S组睁眼时间、拔除气管导管时间、Aldrete评分达到9分时间及PACU停留时间缩短(P〈0.05),吸入麻醉药的总用量和单位时间用量差异无统计学意义(P〉0.05)。结论与异氟醚比较,吸入七氟醚患者麻醉恢复较快,且麻醉恢复质量较好。  相似文献   
72.
目的探讨硬膜外腔注射生理盐水对剖宫产术患者腰麻效果的影响。方法择期行子宫下段剖宫产术患者60例,年龄24~30岁,体重59~73 kg,随机分为2组,每组30例,A组蛛网膜下腔注射规定剂量的0.75%布比卡因后硬膜外腔注射生理盐水5 ml;B组蛛网膜下腔注射0.75%布比卡因。按序贯法进行试验,设定布比卡因的起始剂量为9 mg,剂量梯度为1.5 mg,若上一例有效,则下一例递减一个剂量梯度,若无效则下一例递增一个剂量梯度,蛛网膜下腔阻滞有效的标准为注射布比卡因后20 min内阻滞上平面达T5。采用概率单位法计算ED50。结果A组布比卡因的ED50(5.8 mg)低于B组(8.1 mg),两组比值为0.72,95%置信区间为0.27~0.98,区间范围不包括1,差异有统计学意义(P〈0.05)。结论硬膜外腔注射生理盐水可增强剖宫产术患者腰麻的效果。  相似文献   
73.
The effects of oral omeprazole and oral ranitidine on gastric fluid volume and pH were compared in 95 elective surgical patients, randomly assigned to one of three groups. The patients received either 80 mg of omeprazole or 300 mg of ranitidine orally at 6.00 on the morning of surgery. One third of the patients received no antacid therapy. Following induction, a no. 18 nasogastric tube was passed into the stomach and all available gastric fluid was aspirated. pH and volumes were measured. In the omeprazole- and ranitidine-treated groups, the mean pH was > 5.4 after induction, at completion of surgery and 1 h after operation, although at least one patient in both groups had pH < 2.5. The volumes of gastric aspirates were reduced equally by both drugs. Two patients in the omeprazole group, none in the ranitidine group and eight in the control group (26%) had pH <2.5 with volume> 25 ml at induction. Both drugs appeared to be effective in reducing the volume of intragastric fluid and acidity to acceptable values.  相似文献   
74.
Consciousness presumes a set of integrated functions such as sensory processing, attention, and interpretation, and may depend upon both local and long-range phase synchronization of neuronal activity in cerebral cortex. Here we investigated whether volatile anesthetic isoflurane at concentrations that produce loss of consciousness (LOC) disrupts long-range anterio-posterior and local anterior synchronization of neuronal activity in the rat. In six rats, deep electrodes were chronically implanted in the primary visual cortex (V1) and in two areas of the motor cortex (M1 and M2) for recording of intracortical event-related potentials (ERP). Thirty discrete flashes were presented at random interstimulus intervals of 15–45 s, and ERPs were recorded at stepwise increasing isoflurane concentrations of 0–1.1%. Neuronal synchronization was estimated using wavelet coherence computed from the ERP data band-pass filtered at 5–50 Hz. We found that (1) in the waking state, long-range anterio-posterior coherence in 5–25 Hz and 25–50 Hz frequency bands was significantly higher than local anterior coherence; (2) anterio-posterior coherence in both 5–25 Hz and 26–50 Hz bands was significantly reduced by isoflurane in a concentration-dependent manner; (3) local anterior coherence was not affected by isoflurane at any of the concentrations studied. These findings suggest that a disruption of long-range anterio-posterior rather than local anterior synchronization of neuronal activity precedes the anesthetic-induced loss of consciousness.  相似文献   
75.
The ability to excrete a volume of isotonic saline equal to 10% of body weight infused over 60 min, was examined in awake rats and in rats anesthetized with 1 of the 2 agents most commonly used in renal clearance studies, Inactin or Nembutal. Rats anesthetized with Inactin excreted significantly less of the infused sodium during the period of infusion and in the 120-min post-infusion periods as compared to Nembutal-anesthetized rats or awake rats. Following saline infusion, there was a significantly greater decrease in serum protein concentration (25.5±4.7%) in rats anesthetized with Inactin, compared to that observed in the awake or Nembutal-treated rats. In a separate group of saline-infused awake rats, induction of anesthesia with Inactin resulted in a significant increase in hematocrit and a decrease in serum protein concentration. These studies suggest that Inactin anesthesia decreases the ability of the kidney to excrete a saline load and that, in studies of sodium excretion in the rat, especially if volume expansion is to be part of the experimental protocol, Nembutal rather than Inactin may be the anesthetic of choice.These studies were performed while Drs. Knight and Frankfurt were Fellows in Nephrology of Baylor College of Medicine, and were supported in part by a Clinical Investigatorship award to Dr. Weinman and an Associate Investigatorship award to Dr. Frankfurt from the Veterans Administration. This work was presented in part at the Combined Session, Southern Section, American Federation for Clinical Research and the Southern Society for Clinical Investigation, New Orleans, Louisiana, January 27–29, 1977, and has appeared in abstract form in Clin. Res.25, 61 A (1977)  相似文献   
76.
Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (δ, θ, , β), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 ± 0.13 μg/ml, as determined by high-performance liquid chromatography.  相似文献   
77.
目的 观察不同人工胶体液行急性超容血液稀释(AHHD)对血流动力学的影响.方法 45例ASA Ⅰ~Ⅱ级腹部手术患者,随机分为3组:对照组(C组)、6%羟乙基淀粉组(H组)及4%琥珀酰明胶组(G组).在麻醉诱导后开始输液或扩容:C组输入林格液15 ml/kg,H、G组输入林格液15 ml/kg和胶体液20 ml/kg,均在40 min内完成.监测3组术前、麻醉诱导后、输液或扩容20 min、输液或扩容40 min时心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、心脏指数(CI),外周血管阻力(SVR)的变化.监测H、G组患者扩容前后血细胞比容(Hct)的变化.结果 H、G组在扩容末,Hct下降,H组由术前0.385±0.043降至0.304±0.045,G组由术前0.395±0.035降至0.312±0.038.H、G组HR、MAP、CI、CVP、SVR术前值和麻醉诱导后值与C组的差异没有统计学意义(P>0.05).输液或扩容20 min、输液或扩容40 min时H、G组HR、CI、CVP、MAP高于C组,其差异有统计学意义(P<0.05);在扩容20 ml/kg后H组CVP增高达(13.13±3.51)cm H2O(1 cm H2O=0.098 kPa),G组增加达(14.88±1.33)cm H2O.结论 在40 min内静脉输入20 ml/kg的6%羟乙基淀粉、4%琥珀酰明胶,是一种有效的超容血液稀释方法.但会造成心脏负荷的显著增加,使用异氟醚和硝酸甘油能有效地减轻心脏前负倚.  相似文献   
78.
A hypertensive patient with left cardiac enlargement developed marked hypertension under general anaesthesia, during which time a tourniquet was applied around his thigh. When the tourniquet was released, severe hypotension ensued which responded to therapy. The patient, however, died 16 h later of a myocardial infarction. Because of this incident, the anaesthetic and haemodynamic data of 699 patients who underwent limb surgery with a pneumatic tourniquet inflated for at least an hour were retrospectively examined using multivariate analysis. A 30% increase in systolic and/or diastolic arterial blood pressure occurred in 27% of the total patient material and in 67% of those who had had a general anaesthetic. There was a higher frequency of the occurrence of "tourniquet hypertension" with older age, longer operations and the operation site being the lower rather than the upper limb. Tourniquet hypertension rarely occurred in patients with spinal anaesthesia (2.7%) and brachial plexus blockade (2.5%), while those with intravenous regional anesthesia had a higher incidence (19%) of hypertension.  相似文献   
79.
目的:研究Narcotrend(NT)麻醉深度监护仪对老年腹部手术患者全麻质量的影响。方法:选取医院收治的150例择期行腹部手术老年患者,按照抽签方式将其随机分为观察组和对照组,每组75例。两组手术均采取全身麻醉,对照组凭借临床经验及患者身体指征对麻醉药用量进行调整,观察组在NT麻醉深度监护仪指导下调整麻醉用量,比较两组围手术期麻醉时间、苏醒时间、定向力恢复时间、重症监护病房停留时间及麻醉药使用情况;比较两组患者麻醉前(T0)、麻醉30 min后(T1)及手术结束时(T2)的心率(HR)、平均动脉压(MAP)和NT麻醉监护仪麻醉深度指数(NTI);比较两组手术后Ricker镇静-躁动(SAS)评分、Ramsay镇静(RSS)评分、简易智能量表(MMSE)评分及疼痛视觉模拟(VAS)评分;比较两组患者术后并发症发生率。结果:观察组术后苏醒时间、定向力恢复时间低于对照组,差异有统计学意义(t=2.806,t=2.476;P<0.05);麻醉药依托咪酯和舒芬太尼的使用量显著低于对照组,差异有统计学意义(t=8.349,t=2.158;P<0.05);两组HR、MAP的组内比较T1>T2>T0,NTI的组内比较T0>T2>T1,差异有统计学意义(F=205.467,F=36.545,F=111.677,F=156.932,F=57.659,F=869.035;P<0.05);观察组NTI在T1、T2时组间比较显著低于对照组,差异有统计学意义(t=14.265,t=9.347;P<0.05);两组术后SAS评分、RSS评分、VAS评分及PSQI评分差异均无统计学意义,观察组MMSE评分显著高于对照组,差异有统计学意义(t=7.992,P<0.05);观察组术后并发症总发生率为10.67%,显著低于对照组(25.33%),两组比较差异有统计学意义(x2=5.465;P<0.05)。结论:NT麻醉深度监护仪指导下调整麻醉药用量可减少老年患者术后苏醒时间,加快患者定向力恢复,且能减少术后并发症发生,有较高的临床应用价值。  相似文献   
80.
目的探讨瑞芬太尼和舒芬太尼对行腹腔镜直肠癌根治术的老年患者围术期f血流动力学的影响。方法选取2019年9月一2020年6月在北部战区总医院行直肠病根治术的老年患者40例,随机分为I组和II组.各20例。I组给予七氟烷联合瑞芬太尼麻醉,II组给予七氟烷联合舒芬太尼麻醉。观察比较两组围术期各时间点脑电双频指数.血压、心率,以及麻醉恢复期情况。结果两组气腹后血压和心率均升高,I组气腹后5minf血压高于II组,差异有统计学意义(P<0.05)。拔除气管导管后5 min两组血压和心率均较术前升高,而且I组血压和心率均较II组高,差异有统计学意义(P<0.05)。两组不同时间点脑电双频指数值差异均无统计学意义(P>0.05)。I组自主呼吸恢复时间与拔管时间均较I组长,差异有统计学意义(P<0.05)。两组气腹前后呼气末二氧化碳分压差异无统计学意义(P>0.05)。结论瑞芬太尼和舒芬太尼均能满足行腹腔镜直肠癌根治术老年患者的麻醉要求,而且舒芬太尼对患者围术期血流动力学的影响较小,更有利于老年患者术中麻醉的维持与术后恢复。  相似文献   
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