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1.
瘦素对肠缺血/再灌注损伤大鼠肝脏功能的影响及其机制 总被引:1,自引:0,他引:1
目的:探讨瘦素(leptin)对大鼠肠缺血/再灌注(I/R)损伤时肝脏的保护作用及其机制。方法:99只Wistar大鼠随机分成11组:假手术组,肠缺血45min再灌注15min、30min、1h、3h、6h的肠I/R损伤组和相应时间点的leptin治疗组,每组9只大鼠。肠I/R损伤组和leptin治疗组建立大鼠肠I/R损伤模型;leptin治疗组于再灌注的同时腹腔注射leptin0.2mg/kg。假手术组术后1h处死,其余各组大鼠于相应时间点处死,检测血清丙氨酸转氨酶(ALT),肝组织中白细胞介素-6(IL-6)、IL-10和超氧化物歧化酶(SOD)水平的动态变化。结果:肠I/R组血清ALT随着时间变化逐渐升高,肝组织中的IL-6水平于再灌注3h显著升高,而IL-10水平基本处于平稳的波动状态,SOD活性于再灌注早期呈略微下降趋势,1h后逐步回升至假手术组水平;leptin治疗后血清ALT水平基本稳定在较低水平,再灌注3h后,肝组织IL-6水平较损伤组明显降低,同时SOD活性显著提高,IL-10水平于再灌注15min时突然增高,随即恢复到假手术组水平。结论:leptin对大鼠肠I/R造成的肝脏功能损伤具有改善作用,可能与其调节肝组织中的细胞因子释放、提高肝脏的抗氧化损伤能力有关。 相似文献
2.
白藜芦醇对肝脏缺血再灌注损伤的保护作用 总被引:5,自引:0,他引:5
摘要:探讨白藜芦醇对肝脏缺血再灌注损伤的防护作用。将雄性SD大鼠随机分为空白对照组、缺血再灌注组(I/R组)、I/R加生理盐水处理组和I/R加白藜芦醇处理组。观察肝脏缺血40 min再灌注1,3,6,12h后血清谷丙转氨酶(ALT)、谷草转氨酶(AST)及肝组织丙二醛(MDA)含量的变化以及肝组织病理学改变。结果示肝脏I/R后血清ALT,AST及肝组织MDA含量均显著升高,肝脏缺血再灌注前用白藜芦醇15 mg/kg者,血清ALT,AST及肝组织MDA含量均明显降低,且肝组织病理学损害明显减轻。结果表明白藜芦醇对肝脏I/R损伤具有保护作用 相似文献
3.
血红素加氧酶-1诱导对鼠肝缺血再灌注损伤的保护作用 总被引:1,自引:0,他引:1
目的研究血红素加氧酶-1(heme oxygenase-1,HO-1)在鼠肝缺血再灌注损伤肝组织中的表达及其作用。方法建立小鼠部分肝脏热缺血再灌注损伤模型,36只清洁级Balb/C小鼠随机分为3组: 假手术组(S组)、缺血/再灌注损伤组(I/R组)、HO-1诱导剂氯化高铁血红素(hemin)预处理组(HM组)。免疫组化半定量分析肝组织HO-1蛋白的表达,检测血清AST和ALT,肝组织丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性,并观察肝组织的病理变化。结果与S组比较,I/R组HO-1蛋白表达显著增强,hemin预处理后,HO-1蛋白表达较I/R组增高(P<0.01)。I/R组AST,ALT活性和MDA的含量显著高于S组,而HM组均显著低于I/R组(P<0.01);I/R组SOD活性下降,而HM组显著高于I/R组(P<0.01)。HM组病理损伤程度明显轻于I/R组。结论 HO-1在鼠肝缺血再灌注损伤肝组织中表达上调,对肝脏具有保护效应。 相似文献
4.
《中国矫形外科杂志》2014,(14):1304-1309
[目的]探讨重组人可溶性补体受体1型(Soluble complement receptor type 1,sCR1)对大鼠肢体缺血再灌注(I/R)损伤的保护作用。[方法]采用无创血管夹夹闭左侧股动脉制作大鼠肢体缺血再灌注(Ischemiareperfusion,I/R)损伤模型,观察0、4、8 h时间点sCR1蛋白干预组(B组)与生理盐水(NS)对照组(A组)I/R损伤肌组织细胞形态学变化、测定肌肉湿干重比(W/D)、髓过氧化物酶(MPO)、丙二醛(MDA)、乳酸脱氢酶(LDH)的表达水平。[结果]sCR1蛋白干预后的B组各时间点腓肠肌组织的W/D均低于NS对照A组,以I/R 4 h组最为显著(P<0.01);B组的MDA、MPO、LDH表达水平明显低于A组,以I/R 4 h组最为显著(P<0.01)。[结论]重组人sCR1蛋白对大鼠模型进行sCR1蛋白早期干预后,可明显减轻大鼠后肢骨骼肌I/R的损伤。 相似文献
5.
目的 评价静脉输注高氧液对家兔小肠缺血再灌注损伤的影响.方法 健康成年家兔24只,雌雄不拘,体重2.5 ~ 3.2 kg,采用随机数字表法,将家兔随机分为3组(n=8):假手术组(S组)、小肠缺血再灌注组(I/R组)和静脉输注高氧液组(HOS组).S组仅开腹游离但不夹闭肠系膜上动脉,I/R组和HOS组采用夹闭肠系膜上动脉1h恢复灌注2h的方法制备家兔小肠缺血再灌注模型,于夹闭肠系膜上动脉即刻HOS组耳缘静脉输注高氧液20 ml·kg-1 ·h-1,I/R组静脉输注等容量生理盐水.于再灌注2h时采集下腔静脉血样,检测血清乳酸浓度,处死家兔取小肠组织,测定丙二醛(MDA)含量、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧物酶(GSH-Px)的活性,光镜及电镜下观察肠上皮组织病理学结果,行肠黏膜损伤评分.取内脏组织,观察细菌移位情况.结果 与S组相比,I/R组和HOS组肠组织MDA含量、血清乳酸浓度和细菌移位率升高,SOD、CAT和GSH-Px活性降低(P<0.05);与I/R组相比,HOS组肠组织MDA含量、血清乳酸浓度和细菌移位率降低,SOD、CAT和GSH-Px活性降低(P<0.05).结论 静脉输注高氧液可减轻家兔小肠缺血再灌注损伤. 相似文献
6.
目的 探讨亚甲蓝对兔肝缺血再灌注损伤的影响.方法 健康成年新西兰大白兔24只,雌雄不拘,体重2.0~2.3 kg,随机分为3组(n=8):假手术组(S组)、肝缺血再灌注组(I/R组)和亚甲蓝组(MB组).I/R组及MB组采用夹闭肝左外叶、中叶、右中叶及方形叶肝动脉分支40min再灌注60 min的方法制备肝缺血再灌注模型,S组仅游离相应血管.MB组于再灌注前20 min经耳缘静脉注射亚甲蓝5 mg/kg(用生理盐水稀释至5 ml),S组及I/R组给予等容量生理盐水.于缺血前即刻(T1)、缺血20 min(T2)、加min(T3)、再灌注1 min(T4)、再灌注5 min(T5)、30 min(T6)、60 min(T7)时记录MAP和HR.于T1,5-7时取股动脉血样1 ml,测定血清TNF-α及IL-6的浓度.分别于T1,6,7时取股动脉血样1.5 ml,测定血浆ALT及AST的活性.于T7时测定肝左叶组织SOD活性及MDA含量,光镜下观察肝组织病理学结果.结果 与S组比较,I/R组T4-7,时MAP降低,T7时HR降低,肝组织SOD活性降低,MDA含量升高,I/R组及MB组T3-5时血清TNF-α和IL-6浓度升高,T6,7时血浆ALT和AST活性升高(P<0.05或0.01);与I/R组比较,MB组T4-7时MAP升高,肝组织SOD活性升高,MDA含量降低,T3-5时血清TNF-α和IL-6浓度降低,T6,7时血浆ALT和AST活性降低(P<0.05或0.01).MB组肝组织损伤较I/R组减轻.结论 亚甲蓝可维持血液动力学稳定,减轻兔肝缺血再灌注损伤. 相似文献
7.
目的 探讨肠缺血再灌注对大鼠脑组织小胶质细胞活化的影响.方法 清洁级健康成年雄性SD大鼠128只,体重250-300 g,采用随机数字表法,将其随机分为2组(n=64):假手术组(S组)和肠缺血再灌注组(I/R组).I/R组采用夹闭肠系膜上动脉90 min后再灌注的方法制备肠缺血再灌注损伤模型.于再灌注2、6、24、48 h时观察肠粘膜病理学结果,并行Chiu评分;取脑组织,计数活化的小胶质细胞,计算小胶质细胞活化率,测定脑组织活性氧(ROS)、MDA含量及SOD活性、NO含量、一氧化氮合酶(NOS)及诱导型一氧化氮合酶(iNOS)活性.结果 与S组比较,I/R组肠组织Chiu评分、脑组织活化的小胶质细胞数、小胶质细胞活化率、ROS、NOS和iNOS活性、MDA和NO含量升高,SOD活性降低(P<0.05或0.01);I/R组再灌注6-48 h脑组织ROS、NOS和iNOS活性、MDA和NO含量依次升高,脑组织SOD活性及肠组织Chiu评分依次降低,脑组织活化的小胶质细胞和小胶质细胞活化率于再灌注24h时达峰值(P<0.05或0.01).结论 肠缺血再灌注可通过激活脑组织小胶质细胞,激活NOS和促进ROS生成,从而诱发脂质过氧化反应,该作用作为肠缺血再灌注诱发大鼠脑损伤的机制. 相似文献
8.
乌司他汀对肝脏缺血再灌注损伤的防护作用 总被引:1,自引:0,他引:1
目的 探讨肝脏缺血再灌注(I/R)损伤的发生机制,观察乌司他汀(UTI)对肝脏I/R损伤的保护作用。方法 选择外伤性肝破裂手术中行肝门阻断术患者38例,随机分为I/R组和UTI组各19例。观察肝脏I/R后血清TNF、MDA、AST、ALT变化及再灌注肝组织多形核白细胞(PMN)浸润和肝组织形态学变化。结果 I/R组:血清TNF、MDA、AST、ALT显著升高,肝组织PMN浸润明显增加。电镜下可见肝窦内皮细胞破坏,肝细胞线粒体结构改变。UTI组:血清TNF、MDA、AST、ALT明显降低。肝组织PMN浸润明显减少,肝组织超微结构明显改善。结论肝脏I/R诱导TNF产生。UTI能明显减轻PMN依赖性肝脏I/R损伤。 相似文献
9.
曹辉|胡新华|何家安|刘程伟|辛世杰 《中国普通外科杂志》2010,19(12):1302-1305
目的探讨雷帕霉素靶蛋白(mTOR)信号转导通路在缺血后处理(I-postC)减轻大鼠骨骼肌缺血再灌注(I/R)损伤中的表达及其意义。方法 48只雄性健康Wistar大鼠,以无创动脉夹夹闭右侧股动脉4h,松夹再灌注12h或24h建立大鼠右后肢I/R损伤模型,随机分为I/R组,缺血预处理(IPC)组(5min缺血/5min再灌,3个循环)及I-postC组(1min再灌/1min缺血,3个循环)(n=16),以大鼠左后肢为对照。分别于再灌注后12,24h取标本。观察骨骼肌组织形态学、湿/干重比、丙二醛(MDA)及髓过氧化物酶(MPO)和雷帕霉素靶蛋白的表达的变化。结果 I-postC和IPC组的骨骼肌水肿明显减轻,MDA和MPO亦明显降低,与I/R组比较差异有统计学意义(P0.05)。I-postC组和IPC组之间无差异(P0.05)。I-postC与IPC组mTOR蛋白产物表达显著增加,与I/R组比较差异有统计学意义(P0.05)。结论 I-postC减轻大鼠后肢骨骼肌I/R损伤,与缺血预处理可能存在共同的作用机制,即通过激活mTOR信号转导通路发挥作用。 相似文献
10.
目的 探讨缺血预处理(IPC)对肝硬化大鼠缺血再灌注损伤(I/R)的保护作用,并寻找对肝硬化I/R保护作用的最佳有效时间窗和理想方案.方法 通过构建正常大鼠及肝硬化大鼠模型,以正常肝脏I/R(A组)和正常肝脏10-10 min-IPC方案(B组)为对照组,肝硬化组则分别施行单纯I/R(C组)、5-10 min(D组)、8-10min(E组)、10-10 min(F组)及15-10 min(G组)的IPC方案,每组18只,分别在术后1 h、4 h及24 h三个时间点采静脉血,检测血清ALT、AST、LDH及肝组织中MDA、MPO、NO、SOD水平,评价肝功能及肝脏组织炎性浸润及抗损伤程度.结果 肝脏缺血30 min后肝脏功能受损明显,表现为各组的ALT、AST、LDH水平升高,尤以再灌注4 h时显著(P<0.05),但经过缺血预处理后,各IPC组中的NO、MDA、MPO及SOD水平亦显著高于其对应的I/R组,以E组的差别有显著意义(P<0.05).结论 10-10 min的IPC方案对于正常肝脏I/R确有保护作用,而8-10 min的IPC方案能最有效地启动对肝硬化大鼠肝脏I/R的保护作用. 相似文献
11.
Vasopressor hormone response following mesenteric traction during major abdominal surgery 总被引:1,自引:0,他引:1
A. Brinkmann W. Seeling C. F. Wolf E. Kneitinger C. Schonberger N. Vogt K. H. Orend M. Buchler P. Radermacher M. Georgieff 《Acta anaesthesiologica Scandinavica》1998,42(8):948-956
Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI2) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI2), TXB2 (stabile metabolite of thromboxane A2) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI2 release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB2 (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI2 release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A2, presumably contributing to hemodynamic stability within 30 min after MT. 相似文献
12.
Don Dame 《Artificial organs》1996,20(5):613-617
Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required. 相似文献
13.
Kai von Appen Christoph Weber Udo Losert† Heinrich Schima† Hans-Jürgen Gurland Dieter Falkenhagen 《Artificial organs》1996,20(6):420-425
Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal. 相似文献
14.
T. Tateishi M. Watanabe H. Nakura M. Tanaka T. Kumai T. Aoki S. Kobayashi 《Acta anaesthesiologica Scandinavica》1998,42(9):1028-1032
Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably. 相似文献
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably. 相似文献
15.
Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2 O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg−1 followed by 0.15 mg · kg−1 · h−1 , n=8) or verapamil (0.1 mg · kg−1 followed by 0.3 mg · kg−1 · h−1 , n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO. 相似文献
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO. 相似文献
16.
Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made
of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300
million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly
obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries
were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However,
health-care awareness of obesity and bariatric surgeons are slowly increasing. 相似文献
17.
Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts 总被引:3,自引:0,他引:3
B. Heindl B. F. Becker S. Zahler P. F. Conzen 《Acta anaesthesiologica Scandinavica》1998,42(8):995-1003
Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress. 相似文献
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress. 相似文献
18.
D. Ma S. M. Sapsed-Byrne M. K. Chakrabarti J. G. Whitwam 《Acta anaesthesiologica Scandinavica》1998,42(6):670-677
Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg?1 i. v. and 32 μg · kg?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg?1. The mean ED50s, calculated from dose-response curves, were 5.4 mg · kg?1, 3.9 μg · kg?1 and 0.4 mg · kg?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg?1 and 8 μg · kg?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration. 相似文献
19.
Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery 总被引:1,自引:0,他引:1
J. Boldt M. Papsdorf S. Piper W. Padberg G. Hempelmann 《Acta anaesthesiologica Scandinavica》1998,42(8):941-947
Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg?1 · min?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min?1 · m?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO2I) and oxygen consumption index (VO2I) were also significantly increased in the dopexamine group (DO2I: from 416±91 to 717±110 ml/m2 · m2; VO2I: from 98±25 to 157±22 ml/m2 · m2), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow. 相似文献
20.
A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions. 相似文献