肾上腺髓质素心肌保护作用机制的实验研究

目的　探讨肾上腺髓质素 (Adm1 5 0 )对缺血再灌注大鼠心肌组织血管细胞粘附分子 1(VCAM 1)表达的影响。方法　 2 4只雄性SD大鼠 ,制作离体心脏缺血再灌注模型 ,并随机分为A、B、C、D4组 ,每组 6只。心脏缺血 6 0min ,A组用氧合K H液再灌注 6 0min ,B、C、D组用氧合K H液分别加入10 -9mol/L、10 -8mol/L、10 -7mol/L的Adm1 5 0再灌注 15min ,再用K H液灌注 45min。逆转录 -聚合酶链式反应 (RT PCR)法检测心肌组织VCAM 1mRNA表达 ,并测定磷酸肌酸激酶同工酶 (CK MB)释放。结果　Adm1 5 0抑制再灌注大鼠心肌组织VCAM 1表达的作用呈浓度依赖性。Adm1 5 0减少了再灌注末心肌组织CK MB漏出量 ,A组 ( 31 5± 3 3)U/L、B组 ( 2 9 7± 3 3)U/L、C组 ( 2 4 3± 3 0 )U/L、D组 ( 19 3± 3 2 )U/L ,C、D组与A组比较P <0 0 1。结论　心肌缺血再灌注时 ,Adm1 5 0通过抑制VCAM 1mRNA表达而产生心肌保护作用。     

二氮嗪后处理对大鼠离体心脏缺血再灌注损伤的影响

目的 评价二氮嗪后处理对大鼠离体心脏缺血再灌注损伤的影响.方法 雄性SD大鼠,体重250～300 g,成功建立Langendorff再灌注模型的64个心脏随机分为4组(n=16):正常对照组(C组)、缺血再灌注组(I/R组)、二氮嗪后处理组(D组)和线粒体ATP敏感性钾通道阻断剂5-羟葵酸+二氮嗪后处理组(5-HD+D组).采用K-H液平衡灌注20 min时,C组继续灌注K-H液70 min;I/R组、D组和5-HD+D组进行心肌缺血40 min,I/R组缺血前灌注4 ℃ ST.Thomas停跳液10 ml/kg;D组再灌注5 min时灌注含50μmol/L二氮嗪的K-H液5 min,然后再灌注20 min;5-HD+D组灌注二氮嗪前灌注含100 μmol/L 5-羟葵酸的K-H液5 min,再灌注20 min.分别于平衡灌注末与再灌注末时取8个心脏,记录心功能指标,然后提取线粒体,测定心肌细胞线粒体膜电位(MMP)、氧自由基(ROS)生成量和呼吸功能指标.结果 各组平衡灌注末时各指标差异无统计学意义(P＞0.05).与C组比较,再灌注末时其余3组心功能和线粒体呼吸功能减退,MMP降低,ROS生成量增加(P＜0.05或0.01);与I/R组和5-HD+D组比较,D组心功能和线粒体呼吸功能改善,MMP升高,ROS水平降低(P＜0.01).结论二氮嗪后处理可减轻大鼠心肌缺血再灌注损伤,其机制与开放线粒体ATP敏感性钾通道而改善线粒体功能有关.     

前列地尔乳剂对缺血再灌注心肌的保护作用

目的　研究前列地尔脂肪乳剂 (Lipo PGE1)对大鼠心肌缺血再灌注损伤 (MIRI)的影响。方法　应用Langendorff鼠心脏灌注模型 ,将 3 0只SD大鼠随机分成空白对照组 (A组 )、再灌注时K H液加Lipo PGE1组 (B组 )、停跳液中加Lipo PGE1组 (C组 ) ,各组分别平衡灌注 2 0min后灌注冷晶体停搏液 ,2 5℃缺血 5 0min ,再灌注 60min ,观察比较各组心肌I/R前后心率 (HR )、左室发展压 (LVDP)、左室压力变化速率 (△dp/dt)、冠脉流量 (CF)、冠脉流出液中磷酸肌酸激酶 (CPK)、乳酸脱氢酶 (LDH)含量及再灌注后心肌超氧化物歧化酶 (SOD)活性、丙二醛 (MDA)和ATP含量的变化、心肌细胞超微结构的变化。结果　Lipo PGE1改善心肌I/R后的收缩功能、增加冠脉流量和心肌ATP含量 ,促进SOD活性恢复 ,减少心肌细胞CPK和LDH的漏出及MDA的生成 ,减轻了心肌细胞超微结构的损伤。结论　Lipo PGE1通过其抗氧化和扩张冠脉作用可减轻MIRI。     

异丙酚对离体大鼠心脏再灌注损伤后冠脉儿茶酚胺浓度的影响

目的 通过建立离体大鼠工作心脏灌注模型,测定冠脉流出液儿茶酚胺浓度,研究异丙酚对离体大鼠心脏缺血/再灌注损伤后左室功能及心肌代谢的保护机制。方法 雄性SD大鼠40只,随机分为4组(每组10只),对照组、异丙酚10μmol/L组、50μmol/L组、100μmol/L组。建立工作心脏模型后,所有心脏全心缺血25 min,再灌注30 min。在缺血前5 min、0 min,再灌注后5、10、15、20、25和30 min分别观察心率(HR)、左室发展压与心率乘积(LVDP×HR)、冠脉流量(CF)、心排出量(CO)等心功能指标,并留取冠脉流出液测量肌酸激酶(CK)、儿茶酚胺含量。结果 缺血前,异丙酚组CO、HR、LVPSP及LVDP×HR均显著低于对照组(P<0.05);4组CK值无显著变化(P>0.05),儿茶酚胺测不出。再灌注时,异丙酚组CF、CO、HR、LVEDP、LVPSP及LVDP×HR在相应时点均比对照组恢复明显(P<0.05);异丙酚组CK值显著低于对照组(P<0.05);再灌注后,异丙酚组肾上腺素和去甲肾上腺素显著低于对照组(P<0.05);各组多巴胺含量差别不显著(P>0.05)。结论 异丙酚对离体大鼠心肌缺血/再灌注损伤具有保护作用,其机制之一可能是由于异丙酚抑制心肌缺血再灌注损伤后儿茶酚胺的释放。     

3-硝基丙酸化学预处理对大鼠离体心脏缺血-再灌注损伤的影响

目的研究3-硝基丙酸(3-NPA)化学预处理对大鼠离体心脏缺血-再灌注损伤的保护作用及其机制。方法16只Wistar大鼠随机分为2组,每组8只。实验组(3-NPA组):腹腔注射3-NPAmg·kg-1预处理24h;对照组(C组):腹腔注射等体积生理盐水。采用Langendorff离体心脏灌流模型,两组行常温缺血30min-再灌注60min模拟心肌缺血-再灌注损伤。观察各组缺血前(基础值)和再灌注后30、60min时心率(HR)、左心室发展压(LVDP)、左心室压力上升和下降最大变化速率(±dp/dtmax),测定再灌注后15min时冠脉流出液肌酸激酶(CK)和乳酸脱氢(LDH)活性,测定再灌注后60min时心肌丙二醛(MDA)含量和超氧化物岐化酶(SOD)活性。结果与C组比较,3-NPA组LVDP、 dp/dtmax再灌注后30、60min、-dp/dtmax再灌注后60min时升高(P<0.01或0.05),HR组间比较差异无统计学意义(P>0.05),灌注后15min时冠脉流出液CK和LDH活性降低,再灌注后60min时心肌SOD活性明显升高,心肌MDA含量降低。结论4mg·kg-13-NPA预处理对大鼠离体心脏缺血-再灌注损伤具有一定的保护作用,其机制可能是减少氧自由基的产生和提高SOD活性。     

吡那地尔超极化停搏对大鼠离体心脏蛋白激酶C及热休克蛋白70的影响

目的探讨吡那地尔超极化停搏对大鼠离体心脏蛋白激酶C（PKC）ε及热休克蛋白70 （HSP70）的影响。方法成年雄性SD大鼠,成功建立Langendorff离体再灌注模型的32个心脏,随机分为4组（n=8）：自然停搏组（A组）、St.Thomas组（B组）、吡那地尔超极化组（C组）和白屈菜赤碱组（D组）。A组、B组和C组K-H液平衡灌注15min后,A组停止灌注,B组灌注St.Thomas停搏液,C组灌注超极化停搏液;D组K-H液平衡灌注10min后,白屈菜赤碱液灌注5min,再灌注超极化停搏液。记录各组平衡灌注15min和再灌注20min时冠脉流量（CF）、心率（HR）、左室发展压（LVDP）、左室收缩峰压（LVSP）和左室压力瞬时最大变化率（dp/dtmax）;再灌注30min时测定心肌膜性PKCε和HSP70的表达。结果与K-H液平衡灌注15min时相比,再灌注20min时A组、B组和D组CF、HR、LVSP、LVDP及dp/dtmax降低（P〈0.05）;与C组相比,其余各组再灌注20min时CF、HR、LVSP、LVDP及dp/dtmax降低,膜性PKCε和HSP70的表达下调（P〈0.05）。结论吡那地尔超极化停搏通过上调膜性PKCε和HSP70表达,促进大鼠心肌缺血再灌注时心功能恢复。     

异丙酚、芬太尼对离体心肌缺血再灌注损伤的影响

目的 评价异丙酚、芬太尼对离体心肌缺血再灌注损伤的作用。方法 采用离体鼠Langendroff脏模型,SD大鼠 32只,取心脏用 K-H液恒温恒压主动脉逆灌、平衡 15min,随机分为 4组:（A）脂肪乳剂对照组;（B）5μg·ml-1异丙酚组;（C）10ng·ml-1芬太尼组;（D）5μg·ml-1异丙酚加10ng·ml-1芬太尼组。用含相应药液的 K-H液灌注 10min,常温全心停灌30min,然后用含相应药液的K-H液恢复灌注30min,记录各组用药前、停灌前1min、再灌30min时心脏机械功能变化、冠脉流量以及测定再灌注30min冠脉流出液里乳酸脱氢酶（LDH）活性。结果 再灌30min时B、C、D组心功能的恢复明显好于A组,D组明显好于B、C组。LDH活性B、C、D组明显低于A组,D组明显低于B、C组。结论5μg·ml-1异丙酚、10ng·ml-1芬太尼能抑制离体心肌缺血再灌注损伤,两者复合应用其作用更强。     

细胞穿透肽PEP-1介导血红素加氧酶-1对大鼠离体心脏缺血再灌注损伤的影响

目的 探讨细胞穿透肽PEP-1介导血红素加氧酶-1(HO-1)对大鼠离体心脏缺血再灌注损伤的影响.方法 雄性SD大鼠,体重220～280g,制备Langendorff离体心脏灌注模型,选取模型制备成功的离体心脏18个,随机分为3组(n=6):假手术组(S组)、缺血再灌注组(IR组)和PEP-1/HO-1处理+缺血再灌注组(HO-1组).IR组K-H液平衡灌注30 min后,采用停灌40 min再灌注50 min的方法制备缺血再灌注模型.HO-1组在停灌前用含50 μmol/L融合蛋白PEP-1/HO-1的K-H液平衡灌注15 min,S组采用K-H液持续灌注120 min.再灌注50 min时,收集冠脉流出液,测定肌酸激酶(CK)和乳酸脱氢酶(LDH)的活性;取心肌组织,采用Western blot法测定HO-1蛋白表达水平,采用硫代巴比妥酸比色法测定MDA含量,黄嘌呤氧化酶法测定SOD活性.结果 HO-1组心肌组织HO-1蛋白表达水平较IR组升高(P＜0.01).与S组比较,IR组和HO-1组冠脉流出液CK和LDH活性及心肌组织MDA含量升高,心肌组织SOD活性降低(P＜0.01);与IR组比较,HO-1组冠脉流出液CK和LDH活性及心肌组织MDA含量降低,心肌组织SOD活性升高(P＜0.01).结论细胞穿透肽PEP-1可将HO-1蛋白成功导入心肌组织,并减轻大鼠心肌缺血再灌注损伤.     

缺血预处理对大鼠心肌细胞凋亡的影响及其机制

目的 观察心肌细胞凋亡及其机制在大鼠心肌缺血再灌注损伤和缺血预处理中的作用.方法 将40只大鼠随机分成4组:对照组(A组)、60min缺血再灌注组(B组)、120min缺血再灌注组(C组)、缺血预适应组(D组);应用TUNEL法检测心肌组织的凋亡;心脏病理改变用光学和电子显微镜观察;检测肿瘤坏死因子(TNF)-α、bcl-2和bax因子.结果 D组心肌细胞凋亡指数(11.36±4.23)%明显优于B组(18.14±7.69)%和C组(15.59±6.31)%,D组TNF-α、bel-2和bax的表达也明显优于B、C二组.结论 缺血预处理可减轻大鼠心肌缺血再灌注后心肌细胞的凋亡;TNF-α、bcl-2和bax表达的抑制与缺血预处理保护机制有关.     

异丙酚对大鼠离体心脏缺血再灌注损伤的保护作用

目的从氧化应激和线粒体介导的凋亡方面探讨异丙酚对大鼠离体心脏缺血再灌注损伤的保护作用。方法40只SD大鼠随机分为对照组、缺血再灌注(I/R)组和异丙酚15、30、60μmol·L-1组,每组8只。应用Langendorff离体心脏灌注系统建立心脏缺血再灌注损伤模型,经主动脉用Lock氏平衡灌注。除对照组外,各组均全心缺血25 min再灌注30 min。记录平衡灌注末、缺血前即刻及再灌注30 min时心率(HE)、左室收缩压(LVSP)、左室舒张末压(LVDEP)、左室压力变化速率(±dp/dtmax)、冠脉流量(CF);测定冠脉流出液中乳酸脱氢酶(LDH)、磷酸肌酸激酶(CK)活性及心肌线粒体活力、膜肿胀度、丙二醛(MDA)含量及心肌细胞凋亡率、半胱天冬酶(caspase)-3蛋白的表达。结果与I/R组比较,异丙酚30、60 μmol·L-1组再灌注30min时LVDEP升高,LVDP、±dp/dtmax、CF均降低,冠脉流出液中LDH、CK活性降低,心肌线粒体膜肿胀度、MDA含量降低,线粒体活力升高,心肌细胞凋亡率降低,caspase-3表达降低(P<0.05或0.01)。结论30、60/μmol·L-1异丙酚对大鼠离体心脏缺血再灌注损伤有一定的保护作用,减少缺血再灌所致的氧化应激,保护线粒体,抑制心肌细胞凋亡可能是其作用机制之一。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

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_1α (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.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

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.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

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.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

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.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

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.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.