根治切除术联合抗病毒治疗肝癌合并乙肝病毒感染

探讨根治切除术联合抗病毒治疗肝癌合并乙肝病毒(HBV)感染的临床效果。100例肝癌合并乙肝病毒感染患者,按照HBV-DNA水平不同分成高病毒复制组和低病毒复制组(以HBV-DNA载量为105拷贝/ml为标准),每组又分为抗病毒组和未抗病毒治疗组,比较4组在肝功能、HBV-DNA水平、并发症和住院时间、住院费用差异性。结果显示,抗病毒治疗后患者肝功能明显好转,HBV-DNA水平明显低于未抗病毒治疗,住院时间、费用费用和并发症均优于未抗病毒者;但低病毒复制组在并发症和住院时间、住院费用上优于高病毒复制组。结果表明,抗病毒结合根治切除术能改善肝癌合并HBV感染肝功能和病毒指标,缩短住院时间。     

乙肝相关性肝癌患者术前HBV-DNA载量水平与术后肝功能恢复的关系分析

目的探讨乙肝相关性肝癌(HCC)患者术前HBV-DNA载量水平与术后肝功能恢复的关系。方法将56例行肝癌根治术的HCC患者按术前血清中HBV-DNA载量分为低复制组(血清HBV-DNA载量≤104IU/ml,n=35)和高复制组(血清HBV-DNA载量≥105IU/ml,n=21),观察比较术前3 d和术后7 d HBV-DNA载量变化例数及ALT、AST、ALB、TBIL等肝功能指标变化、肝功能恢复时间,同时记录两组患术后并发症发生情况。结果两组患者手术前、后血清中HBV-DNA载量无显著性变化(P0.05),两组患者术后7 d ALT、AST、TBIL指标较术前3 d显著升高(P0.05),而三组术后ALB指标较治疗前显著降低(P0.05),且高复制组ALT、AST指标显著高于低复制组(P0.05),而两组在ALB和ABIL等指标比较,差异不具有统计学意义(P0.05)。而低复制组肝功能恢复天数显著短于高复制组,差异具有统计学意义(P0.05)。高复制组患者术后并发症(47.62%)显著高于低复制组患者(17.14%),差异具有统计学意义(P0.05)。结论 HCC患者术前血清HBV-DNA的高水平载量将显著延长患者术后肝功能恢复时间,同时增加患者术后并发症发生风险。     

抗病毒治疗对乙型肝炎病毒相关性肝癌根治性切除术后临床转归的影响

目的:探讨手术前后抗病毒治疗对乙型肝炎病毒(HBV)相关性肝癌根治性切除术后临床转归的影响。方法:回顾性分析135例行肝癌根治性切除术的高载量HBV相关性肝癌患者,依据手术前后是否进行抗病毒治疗分为两组:单纯行根治性切除术的患者为对照组(65例),行根治性切除术联合抗病毒治疗的患者为实验组(70例)。比较两组患者术后Child-Pugh评分、HBV DNA拷贝量、肝储备功能、术后并发症发生情况、术后无瘤生存时间的差异。结果:对照组与实验组在术后不同阶段,HBV DNA拷贝及Child-Pugh评分方面均具有明显统计学差异(P0.001);同时实验组与对照组患者术后急性肝功能衰竭(P=0.0289)、肝性脑病(P=0.0216)、肝肾综合征(P=0.0411)的发病率均具有显著统计学差异;在术后无瘤生存率方面,对照组和实验组患者1年、2年、3年无瘤生存率分别为80.0%、36.9%、13.8%和92.9%、64.3%、31.4%,1年无瘤生存率相比无明显统计学差异(P=0.2598),2年、3年无瘤生存率相比均有明显统计学差异(P=0.0015、P=0.0153),Log Rank分析可得3年总体无瘤生存率差异有统计学意义(P0.001)。结论:肝癌根治性切除术联合抗病毒治疗可以明显降低术后并发症的发生率,促进肝功能恢复,延长患者的无瘤生存期。     

乙肝相关性肝癌术前乙型肝炎病毒DNA载量与围手术期并发症的关系

目的:探讨乙肝相关性肝癌(HCC)患者术前乙型肝炎病毒(HBV)DNA载量与围手术期并发症发生的关系。方法:收集2010年1月—2014年12月行根治性手术治疗的HCC患者共374例资料,按照术前HBV DNA载量分为低载量组(1.0 E+04 IU/m L)和高载量组(≥1.0E+04 IU/m L)。比较两组患者术后肝功能变化情况、并发症及住院时间,并分析并发症与临床病理因素的关系。结果:两组患者各项血清肝功能指标术后均呈先升后降的趋势,但高载量组各项指标上升的幅度及峰值均大于低载量组(部分P0.05)。与低载量组比较,高载量组术后肺部感染(18.9%vs.5.2%)、胆汁漏(15.4%vs.2.3%)、总并发症发生率(19.9%vs.10.6%)增高、术后住院时间(13.70 d vs.10.09 d)延长低(均P0.05)。多因素分析提示,术前HBV DNA载量(OR=0.865)、肝功能Child-Pugh分级(OR=0.731)及肿瘤大小(OR=0.535)是引起手术并发症的独立危险因素(均P0.05)。结论:术前高HBV DNA载量的HCC患者围术期并发症增加及术后住院时间明显延长,术前HBV DNA载量是引起手术并发症的独立危险因素。     

血清HBV-DNA载量与肝细胞癌患者手术风险的临床关系

目的:探讨肝细胞癌患者血清中乙肝病毒的脱氧核糖核酸(HBV-DNA)载量与肝细胞癌患者手术风险的临床关系。方法:回顾性分析2013年7月—2015年7月收治的86例肝细胞癌患者的临床资料,根据术前HBVDNA载量将患者分为低复制组(40例)和高复制组(46例),比较两组患者围手术期临床资料,分析HBV-DNA载量与手术风险的相关性。结果:高复制组在麻醉时间、手术时间、术中出血量水平高于低复制组,半阻断例数高于低复制组,但差异无统计学意义(P0.05),住院时间较低复制组显著延长(P0.05);术后1 d两组患者ALT、AST均较术前显著升高(P0.05),且高复制组显著高于低复制组(P0.05),术后3、7 d两组ALT、AST水平均下降,且高复制组下降幅度显著高于低复制组(P0.05),两组患者术后1、3、7 d TBIL水平较术前无明显变化(P0.05),且组间差异无统计学意义(P0.05);低复制组并发症发生率显著低于高复制组(P0.05)。低复制组并发症Clavien-Dindo分级低于高复制组,差异有统计学意义(P0.05)。结论:术前肝细胞癌患者血清HBV-DNA载量越高,围手术期肝功能恢复时间长,住院时间延长,且并发症发生率高,手术相关风险较大。     

原发性肝癌患者围手术期乙型肝炎病毒DNA的变化及其影响因素

目的 探讨乙肝相关性肝癌患者围手术期乙型肝炎病毒(HBV) DNA水平变化的影响因素,比较抗病毒治疗与未抗病毒治疗对患者术后肝功能恢复的影响.方法 选择55例未达到抗病毒治疗标准的乙肝相关性肝癌患者,定量检测其术前和术后第3天的HBV DNA载量及白细胞介素(IL)-6、IL-10、IL-27的水平.根据术后HBV DNA载量,将患者分成HBV DNA升高(激活)组和不变组.升高组给予抗病毒治疗.记录所有患者术前、术后肝功能指标.用SPSS 13.0进行统计学分析.结果 (1)全组患者HBV激活率为45％(25/55),术前HBV DNA＜1×104 IU/ml的患者,术后HBV激活占激活总数的76％(19/25).(2) Logistic回归分析显示肿瘤直径(P=0.037,0.006)及肝切缘无水酒精注射(P=0.004)是引起HBV再激活的独立危险因素.(3)酶联免疫吸附测定(ELISA)结果:术后IL-10升高与HBV再激活有关(P=0.001),IL 6升高及IL-10降低与HBV不变有关(P=0.000).(4)术后HBV DNA升高且行抗病毒治疗的患者,术后肝功能恢复情况与其他患者比较差异无统计学意义(P＞0.05).结论 肝癌切除术可能引起患者HBV再激活,围手术期内应监测HBV DNA载量的变化.肿瘤直径、术中行肝切缘无水酒精注射术是HBV再激活的独立危险因素.患者术后IL-10、IL-6水平的变化可能与HBV DNA的变化有关.术后HBV再激活近期不会加重肝功能损伤,术后抗病毒治疗对患者近期肝功能的恢复无明显促进作用.     

射频消融与部分肝切除术治疗原发性小肝癌效果比较

目的比较射频消融与部分肝切除术治疗原发性小肝癌的效果。方法选取2015-08—2017-08间鄢陵县人民医院收治的48例原发性小肝癌患者。将行射频消融治疗的患者作为观察组,行部分肝切除术的患者作为对照组,各24例。比较2组患者术后的肝功能指标、住院时间及住院费用。结果术后观察组患者的肝功能指标均优于对照组,住院时间及住院费用均少于对照组,差异有统计学意义(P0.05)。结论与部分肝切除术比较,射频消融治疗原发性小肝癌,对患者术后肝功能影响小,且费用低、疗程短,有利于促进患者的恢复。     

血清 HBV DNA 定量与 HBV 相关性肾炎患者临床病理特征及预后的相关性

目的：探讨HBV相关性肾炎（ HBV-GN）患者血清HBV DNA复制水平与临床病理特征及预后的相关性。方法选取2009年1月至2012年10月在青岛大学附属医院接受治疗的HBV-GN患者102例。采用荧光定量聚合酶链反应法测定所有患者血清HBV DNA载量,并依此将患者分为HBV DNA低度复制组（ HBV DNA＜103拷贝／mL）、HBV DNA中度复制组（103拷贝／mL≤HBV DNA≤105拷贝／mL）和HBV DNA高度复制组（ HBV DNA﹥105拷贝／mL）。所有患者行肾脏穿刺活检,明确病理类型,并进行肾脏组织中HBV相关抗原（ HBsAg、HBcAg及HBeAg）的免疫荧光定量检测。所有患者均接受拉米夫定（100 mg／d）联合阿德福韦酯（10 mg／d）治疗,随访观察18个月,并对各组患者治疗前后的肾功能和生化免疫学指标进行比较。采用One-way ANOVA单因素方差分析比较不同HBV DNA复制水平的患者肾功能、生化免疫学指标、肾脏组织中HBV相关抗原沉积的差异,并采用Spearman相关分析法分析血清HBV DNA水平与肾脏病理分期的相关性。结果102例患者中, HBV DNA低度复制组20例,HBV DNA中度复制组51例,HBV DNA高度复制组31例。随着血清HBV DNA复制水平的增高,患者24 h尿蛋白定量、胆固醇及三酰甘油呈现不同程度的增加（ F＝34.64,40.10和31.72,P＜0.01）,血浆白蛋白降低（F＝24.04,P ＜0.01）;肾脏组织中 HBV 抗原（HBsAg、HBcAg及HBeAg）免疫复合物的沉积增加（F＝41.49,15.64和10.41,P＜0.01）。对78例膜性肾病（MN）患者分析发现,随着血清HBV DNA复制的增加,HBV-MN患者病理分期加重（r＝0.38, P＜0.01）。抗病毒治疗后,各组24 h尿蛋白排泄量较治疗前均显著下降（ t＝7.86,19.28和16.74, P＜0.01）;补体C3较治疗前上升,但与治疗前比较差异无统计学意义（t＝1.05,1.04和1.94,P＞0.05）;血肌酐较治疗前无明显变化（ t＝0.14,0.52和0.57,P＞0.05）。治?     

52例HBeAg阴性HBV相关性肝细胞癌患者的临床分析

目的通过对HBeAg阴性慢性乙型肝炎进展为肝癌（HCC）患者的临床资料进行回顾性分析,探讨该病的发生规律和临床特征。方法对本院收治的52例HBeAg阴性HCC患者的性别、年龄、生化学指标、HBV DNA载量、免疫学状态以及服药情况等进行综合分析并进行统计学处理。结果52例HBeAg阴性HCC患者的血清HBV DNA分布：＜103拷贝/ml者18例（34.63%）,103～105拷贝/ml者22例（42.30%）,＞105拷贝/ml者12例（23.07%）。血清HBV DNA载量愈高的患者肝损伤愈重。抗-HBe （-）/抗-HBe（＋）和抗-HBs（-）/抗-HBs（＋）不同血清HBV DNA的分布无相关性,HCC的发生与抗-HBe和抗-HBs是否出现无关。经抗病毒药物治疗的HCC发生例数显著低于未使用过药物者,提示抗病毒药物能降低或延缓HCC的发生。结论对于HBeAg阴性慢性乙型肝炎患者,尤其是有重症化和肝硬化病理基础、年龄偏大的患者,其HBeAg转阴可能是在药物作用下实现的自然血清学转换伴HBV DNA水平下降至正常,甚至有患者出现HBSAg阴转;也可能是病毒发生变异所致;此两类患者均应警惕HCC的发生。     

慢性乙型肝炎T淋巴细胞HLA-DR抗原表达与HBV DNA和HBeAg含量关系的初步分析

目的 探讨慢性乙型肝炎（CHB）患者HBV DNA、HBeAg含量不同时外周血T淋巴细胞人白细胞抗原DR（HLA-DR）的表达情况.方法 收集2008年9月-2009年10月杭州市第六人民医院134例CHB患者,另外选取36名健康体检者作为对照.用流式细胞仪检测所有研究对象外周血CD3＋HLA-DR＋、CD4＋HLA-DR＋和CD8＋HLA-DR＋T淋巴细胞HLA-DR抗原的表达;实时荧光定量PCR法检测血清HBV DNA含量,化学发光法定量检测血清HBeAg含量.所有患者根据血清HBV DNA载量分为HBV DNA阴性组（≤103拷贝/mL）、低载量组（＞103～105拷贝/mL）、中载量组（＞105～107拷贝/mL）和高载量组（＞107～109拷贝/mL）;根据血清HBeAg含量分为HBeAg阴性组（≤1 PEIU/mL）、低含量组（＞1～100 PEIU/mL）、中含量组（＞100～1 000 PEIU/mL）和高含量组（＞1 000～10 000 PEIU/mL）.组间比较采用t检验和单因素方差分析.结果随着HBV DNA、HBeAg含量的升高,CD3＋HLA-DR＋、CD4＋HLA-DR＋和CD8＋HLA-DR＋细胞百分比降低,其中CD8＋HLA-DR＋细胞百分比降低尤为明显.与HBV DNA阴性组比较,高载量组CD3＋HLA-DR＋、CD4＋HLA-DR＋和CD8＋HLA-DR＋细胞百分比均明显减少,差异具有统计学意义（t=3.686、4.592和3.216,P值均＜0.01）;中载量组CD4＋HLA-DR＋和CD8＋HLA-DR＋细胞百分比均明显减少,差异具有统计学意义（t=3.761和2.862,P值均＜0.01）;低载量组CD8＋HLA-DR＋细胞百分比明显减少,差异有统计学意义（t=2.215,P值＜0.05）.与HBeAg阴性组比,HBeAg高含量组、中含量组CD3＋HLA-DR＋、CD4＋HLA-DR＋和CD8＋HLA-DR＋细胞百分比均明显减少,差异具有统计学意义（t高含量=3.144、2.222和4.035;t中含量=3.311、2.362和3.374,P值均＜0.05）;HBeAg低含量组CD8＋HLA-DR＋细胞百分比明显减少,差异具有统计学意义（t=2.029,P值＜0.05）.结论 联合检测患者血清HBV DNA、HBeAg含量以及T淋巴细胞HLA-DR抗原表达不仅有助于评价CHB患者的免疫状况,对疾病进展和临床疗效评价也具有一定的指导意义.     

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 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.     

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.     

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.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

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.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

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.