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1.
目的探讨竹节参皂苷对异氟醚所致发育期大鼠海马神经毒性及认知功能的影响。方法 7日龄SD大鼠60只,雌雄不限,体重20~25g,随机分为四组(n=15)。对照组(Con组):吸入对照气(空气)6h;异氟醚组(Iso组):吸入1.8%异氟醚6h;竹节参皂苷+异氟醚组(Iso+ChIV组):麻醉前30min腹腔注射竹节参皂苷30mg/kg后吸入1.8%异氟醚6h;竹节参皂苷(ChIV组):麻醉前30min腹腔注射竹节参皂苷30mg/kg后吸入对照气(空气)6h。麻醉结束后12h取海马组织检测突触后致密蛋白95(PSD95)、突触素I(Synapsin I)、B淋巴细胞瘤2相关X蛋白(Bax)、B淋巴细胞瘤2(Bcl-2)蛋白含量,TUNEL染色检测神经元凋亡情况,测定乳酸脱氢酶(LDH)活性。于出生后第31~35天采用水迷宫评估空间学习记忆能力。结果与Con组比较,Iso组PSD95、Bcl-2蛋白含量明显降低,Bax蛋白含量明显升高,TUNEL阳性细胞数明显增多,LDH活性明显增强(P0.05);与Iso组比较,Iso+ChIV组PSD95、Bcl-2蛋白含量明显升高,Bax蛋白含量明显降低,TUNEL阳性细胞数明显减少,LDH活性明显减弱(P0.05)。与Con组比较,Iso组第34和35天逃避潜伏路线明显延长(P0.05),第33、34和35天逃避潜伏期明显延长(P0.05),第35天目标象限停留时间明显缩短,平台穿越次数明显减少(P0.05)。与Iso组比较,Iso+ChIV组第34和35天逃避潜伏路线明显缩短,逃避潜伏期明显缩短(P0.05),第35天目标象限停留时间明显延长,平台穿越次数明显增多(P0.05)。结论竹节参皂苷可明显改善异氟醚所致发育期大鼠神经毒性和认知功能,其机制可能与抑制发育期神经凋亡有关。  相似文献   

2.
目的探讨毒扁豆碱对异氟醚麻醉大鼠认知功能的影响及其机制。方法 2月龄SD大鼠80只,随机分为四组,每组20只。对照组(C组)吸入含有30%氧气的空氧混合气体6h;异氟醚组(I组)吸入1.4%的异氟醚6h;毒扁豆碱+异氟醚组(PI组)与毒扁豆碱组(P组)腹腔注射毒扁豆碱100μg/kg,每8小时一次,共3次。首次给药后,PI组吸入1.4%异氟醚6h;P组吸入同浓度载气6h。麻醉结束行动脉血气分析,12h后取海马组织,ELISA法检测TNF-α、IL-1β、IL-6含量,RTPCR法检测capase-3mRNA的表达。光镜下观察海马CA1区锥体细胞形态学变化。麻醉后第2~7天评估认知功能。结果四组大鼠动脉血气指标、血糖和海马TNF-α含量差异均无统计学意义。与C组和P组比较,I组和PI组大鼠海马IL-1β、IL-6含量、capase-3mRNA明显升高,第4~6天逃避潜伏期明显延长,探索时间明显缩短(P0.05)。与I组比较,PI组大鼠海马IL-1β、IL-6含量、caspase-3mRNA表达明显降低,第4~6天逃避潜伏期明显缩短,探索时间明显延长(P0.05)。结论毒扁豆碱改善了异氟醚麻醉引起的大鼠认知功能损害,其机制可能与抑制海马炎性反应及神经元凋亡有关。  相似文献   

3.
目的 评价吸入不同浓度异氟醚对老龄大鼠海马细胞色素c(Cyt c)表达的影响.方法 健康雄性老龄SD大鼠63只,月龄20月,体重500~600 g,随机分为3组(n=21),对照组(C组):吸入30%氧气2 h;0.75%异氟醚组(L组):吸入0.75%异氟醚和30%氧气的混合气体2 h;1.5%异氟醚组(I2组):吸入1.5%异氟醚和30%氧气的混合气体2 h.分别于麻醉30 min、1和2 h时,各组取5只大鼠,取动脉血样行血气分析.于麻醉结束后24 h时,各组取8只大鼠,测定认知功能;取8只大鼠,分别采用免疫组化法和Western blot法测定海马Cyt c 的表达水平.结果 与C组比较,Ⅰ1组和Ⅰ2组逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少,海马Cyt c表达上调(P<0.05);与Ⅰ1组比较,Ⅰ2组逃避潜伏期、原平台象限停留时间缩短和穿越原平台次数差异无统计学意义(P>0.05),海马Cyt c表达上调(P<0.05).结论 吸入异氟醚可通过上调海马Cyt c的表达导致老龄大鼠认知功能障碍.  相似文献   

4.
目的 探讨手术对老龄大鼠异氟醚麻醉下术后认知功能的影响.方法 健康雄性老龄SD大鼠72只,年龄20月,体重500~600 g,随机分为3组(n=24):对照组(C组)、异氟醚麻醉组(I组)和手术组(O组).C组吸入30%氧气2 h,I组吸入1.5%异氟醚和30%氧气的混合气体2 h,O组吸入1.5%异氟醚和30%氧气的混合气体2 h,并实施腹部手术.于麻醉结束后或术后24 h时随机取8只大鼠,取海马组织,采用免疫组织化学法和RT-PCR法分别测定神经元胆碱乙酰转移酶(ChAT)及ChAT mRNA的表达水平,其余大鼠进行Morris水迷宫实验,测定认知功能.结果 与C组比较,I组和O组逃避潜伏期延长,原平台象限停留时间缩短,穿越原平台次数减少,海马神经元ChAT mRNA及其蛋白表达水平降低(P<0.05);与I组比较,O组术后第4、5天逃避潜伏期延长,原平台象限停留时间缩短,海马神经元ChAT mRNA及其蛋白表达水平降低(P<0.05);与麻醉结束后或术后第3天比较,C组第4、5天逃避潜伏期差异无统计学意义(P>0.05),I组和O组逃避潜伏期延长(P<0.05);I组和O组麻醉结束后或术后第4、5天逃避潜伏期差异无统计学意义(P>0.05).结论 手术操作可加重异氟醚引起的老龄大鼠术后认知功能障碍,其机制可能与海马胆碱能神经元受损有关.  相似文献   

5.
目的 观察米诺环素对异氟醚诱导的发育期大鼠神经元毒性的保护作用.方法 取新生SD大鼠皮层,随机分为四组,每组10只.正常对照组(C组)神经元在37℃空气处理6h,异氟醚麻醉组(A组)神经元在37℃下用1.5%异氟醚处理6h,米诺环素1μmol/L组(M1组)和米诺环素10μmol/L组(M2组)神经元分别在异氟醚处理10 min前加入米诺环素1μmol/L、10μmol/L.相差显微镜下观察四组神经元形态,TUNEL法检测神经元凋亡,MTT法检测神经元活性.结果 A组神经元胞体肿胀、变形且与M1组神经元形态接近;M2组神经元形态改变不明显且与C组相近.MTT结果 显示,与C组、M2组相比,A组、M1组神经元活性显著降低(P<0.05),凋亡神经元数目显著增多(P<0.05).结论 米诺环素能减轻异氟醚诱导的发育期大鼠神经元毒性,具有保护作用.  相似文献   

6.
目的 评价异氟醚对老龄大鼠海马CA3区突触素表达的影响.方法 雌性清洁级SD大鼠63只,月龄24月,体重400~650 g,随机分为3组(n=21):对照组(C组)、1.2%异氟醚组(E_1组)和1.8%异氟醚组(E_2组).C组吸入含40%氧气的空氧混合气体3 h;E_(1,2)组吸入3%异氟醚行麻醉诱导,待翻正反射消失后再分别吸入1.2%、1.8%异氟醚维持3 h.各组随机取12只大鼠,于麻醉结束后第1天采用Morris水迷宫系统测定大鼠认知功能(逃避潜伏期和探索时间),连续测定7 d;随机取9只大鼠于麻醉结束后第1、3和7天处死,测定海马CA3区突触素的表达水平.结果 与C组比较,E_1组和E_2组麻醉结束后第2、3天逃避潜伏期延长(P<0.05或0.01),第4~6天逃避潜伏期差异无统计学意义(P>0.05),麻醉结束后海马CA3区突触素表达持续下调(P<0.05).三组探索时间比较差异无统计学意义(P>0.05);与E_1组比较,E_2组逃避潜伏期差异无统计学意义(P>0.05),海马CA3区突触素表达下调(P<0.01).结论 异氟醚致老龄大鼠认知功能障碍与海马突触素表达无关.  相似文献   

7.
目的 探讨异氟醚对大鼠海马高级糖基化终末产物受体(RAGE)表达的影响.方法 雄性老龄SD大鼠45只,月龄24月;雄性成年SD大鼠45只,月龄4月,分为老龄组和成年组(n=45),每组再分为3个亚组(n=15):老龄对照组(OC组)和成年对照组(AC组)吸入含30%氧气的空氧混合气体;老龄单次吸入异氟醚组(OS组)和成年单次吸入异氟醚组(AS组)吸入1.5%异氟醚2 h;老龄多次吸入异氟醚组(OR组)和成年多次吸入异氟醚组(AR组)吸入1.5%异氟醚3次,2 h/次,每天1次.吸入异氟醚后1 d各组随机取8只大鼠行Morris水迷宫实验测定认知功能,余大鼠处死取海马,采用RT-PCR法检测RAGE mRNA的表达水平,免疫组织化学法检测RAGE蛋白的表达水平.结果 与OC组比较,OS组和OR组认知功能减退,海马RAGE mRNA及其蛋白的表达上调(P<0.05);与AC组比较,AS组和AR组认知功能减退,AR组海马RAGE mRNA及其蛋白的表达上调(P<0.05);与OS组比较,OR组认知功能减退,海马RAGE mRNA表达上调(P<0.05);与AS组比较,AR组认知功能减退,海马RAGE mRNA及其蛋白的表达上调(P<0.05).结论 异氟醚可导致老龄和成年大鼠认知功能降低,尤其对老龄大鼠影响明显,可能与其上调海马RAGE表达有关.  相似文献   

8.
目的 探讨褪黑素对异氟醚麻醉诱发老龄大鼠认知功能障碍的影响.方法 雄性SD大鼠75只,18 ~20月龄,体重350-400 g,采用随机数字表法,将其随机分为5组(n=15):对照组(C组)吸入含有30%氧气的空氧混合气体4h;异氟醚麻醉组(Ⅰ组)吸入1.5%异氟醚4h;褪黑素5 mg/kg组(M1组)、褪黑素10 mg/kg组(M2组)、褪黑素20 mg/kg组(M3组)分别于麻醉前15 rin和麻醉开始后3h时腹腔注射褪黑素5、10、20 mg/kg(溶解于含1% DMSO的生理盐水中),吸入1.5%异氟醚4h.麻醉结束即刻每组取5只大鼠,进行动脉血气分析,测定血糖水平和海马磷酸化Tsu(p-Tsu)蛋白的表达.麻醉结束后14 d时,每组取10只大鼠测定认知功能,然后处死大鼠,取海马组织,采用Westernblot法检测-Tsu蛋白的表达.结果 五组间动脉血气指标和血糖水平差异无统计学意义(P>0.05).与C组比较,Ⅰ组和M1组第3-5天时逃避潜伏期延长,探索时间缩短,海马p-Tsu蛋白表达上调(P<0.05),M2组和M3组逃避潜伏期、探索时间和海马p-Tsu蛋白表达差异无统计学意义(P>0.05);与Ⅰ组和M1组比较,M2组和M3组第2-5天时逃避潜伏期缩短,探索时间延长,海马p-Tsu蛋白表达下调(P<0.05);Ⅰ组与M1组间、M2组与M3组间逃避潜伏期、探索时间和海马p-Tsu蛋白表达比较差异无统计学意义(P>0.05).结论 褪黑素(10和20 mg/kg)可改善异氟醚麻醉诱发老年大鼠认知功能障碍,其机制可能与其抑制海马Tsu蛋白过度磷酸化有关.  相似文献   

9.
【摘要】 目的 比较右美托咪啶(Dex)预处理给药和分次给药两种方法对异氟醚(Iso)致新生大鼠海马细胞凋亡的影响。方法 将出生后7天(postnatal day 7, P7)的SD大鼠随机分成6组:空气+盐水组(Air+NS组)、空气+Dex 25 μg·kg-1分次给药组(Air+Dex25×3组)、空气+Dex 75 μg·kg-1预处理组(Air+Dex75组)、异氟醚+盐水组(Iso+NS组)、异氟醚+ Dex 25μg·kg-1分次给药组(Iso+Dex25×3组)以及异氟醚+Dex 75μg·kg-1预处理组(Iso+Dex75组)。前3组吸入空气,后3组吸入0.75%异氟醚6 h。Air+NS组、Iso+NS组、Air+Dex75组和Iso+Dex75组在麻醉前20 min腹腔内注射生理盐水或75 μg·kg-1剂量的Dex;Air+Dex25×3组和Iso+Dex25×3组分别在麻醉前20 min,麻醉开始后2 h和4 h腹腔内重复注射25μg·kg-1剂量的Dex。麻醉结束后用原位末端标记(TUNEL)法检测海马神经细胞凋亡(n=4); 用Western blot检测海马激活型caspase-3蛋白表达变化(n=4)。 结果 异氟醚能诱导海马CA1区TUNEL阳性细胞数增加391.0 %(P<0.001);激活型caspase-3表达增加122.0%(P<0.001)。Iso +Dex25×3组和Iso+Dex75分别减少异氟醚诱导的TUNEL阳性细胞的增加为80.7%(P<0.001)和73.2%(P<0.001);两组均能完全抑制激活型caspase-3表达的增加(P<0.001);两组间无统计学差异(P>0.05)。结论 右美托咪啶预处理给药和分次给药都能通过抑制海马细胞凋亡来减轻异氟醚对新生大鼠的脑毒性作用,且两者的抗凋亡效果相似。  相似文献   

10.
目的观察异氟醚对东莨菪碱致空间认知障碍大鼠脑皮层和海马组织中胆碱乙酰基转移酶(ChAT)、胆碱能毒蕈碱受体(M-R)、N-甲基-D-天冬氨酸受体(NMDA-R)活性的影响.方法雄性SD大鼠55只随机分为8组对照/1 d组(Con/1 d),异氟醚/1 d组(Iso/1 d),东莨菪碱/1 d组(Sco/1 d),异氟醚+东莨菪碱/1 d组(Iso+sco/1 d);对照/7 d组(Con/7 d),异氟醚/7 d组(Iso/7 d),东莨菪碱/7 d组(Sco/7 d),异氟醚+东莨菪碱/7 d组(Iso+sco/7 d).Iso组、Iso+sco组大鼠每天吸入1 MAC(1.5%)异氟醚2 h,连续4 d.在末次给药后1 d,对Sco/1 d组、Iso+sco/1 d组大鼠腹腔注射东莨菪碱0.8 mg/kg,连续3 d;在末次给药后7 d,对Sco/7 d组、Iso+sco/7 d组大鼠给与相同处理.给药完毕后急性断头处死大鼠,分离脑皮层和海马,Fonnum法测ChAT酶活性,放射配体结合分析法测定M-R和[3H]QNB、NMDA-R和[3H]MK-801的结合活性,并选择1d组大鼠的海马进行受体饱和实验,用Scatchard作图法分析M-R的平衡解离常数(Kd)和最大受体结合量(Bmax)的变化.结果各组大鼠皮层和海马组织的ChAT酶和NMDA-R活性、皮层M-R活性和Kd和Bmax无差异.与Con/1 d组和Iso/1 d组相比,Sco/1 d组、Iso+sco/1 d组海马M-R活性降低(P<0.01).与Con/1 d组相比,Iso/1 d组海马M-R活性增高(P<0.05).与Sco/1 d组相比,Iso+sco/1 d组海马M-R活性增高(P<0.01).与Con/7 d组和Iso/7 d组相比,Iso+sco/7 d组和Sco/7 d组海马M-R活性降低(P<0.05).与Con/1 d组与Iso/1 d组相比,Sco/1 d组和Iso+sco/1d组的Kd增高(P<0.01).与Con/1 d组和Sco/1 d组相比,Iso/1 d组和Iso+sco/1 d组的Bmax增高(P<0.01).结论大鼠持续吸入1.5%异氟醚4 d(每天2 h)可引起海马M-R密度的短暂改变,增加海马M-R活性.  相似文献   

11.
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-PGF (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.
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.
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 H2O 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   

15.
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   

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.
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   

18.
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   

19.
20.
Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.  相似文献   

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