258例儿童原发性IgA肾病临床与病理分析

目的分析258例儿童原发性IgA肾病的临床和病理特点。方法收集自2008年12月至2017年12月于成都市妇女儿童中心医院儿童肾脏内科肾活检诊断为IgA肾病患儿258例。所有肾活检样本均行光镜、免疫荧光和电镜检查。比较IgA肾病不同病理分级和临床特点的相关性。结果 258例IgA肾病患儿平均年龄为(9.3±3.2)岁,男女比为2.23∶1。临床表现为孤立性血尿型84例,肾脏病理Lee氏分级以Ⅱ级为主(51.1%);孤立性蛋白尿型45例,Lee氏分级以Ⅱ级为主(40.0%);血尿和蛋白尿型72例,Lee氏分级以Ⅲ级为主(56.9%);急性肾炎型4例,其中Lee氏分级为Ⅲ级者2例,Ⅱ、Ⅳ级各1例;肾病综合征型50例,Lee氏分级以Ⅲ级为主(80.0%);慢性肾炎型3例,其中Lee氏分级为Ⅳ级者2例,Ⅴ级1例。不同临床型IgA肾病患儿的免疫球蛋白主要沉积形式为IgA、IgM、C3共沉积;随着病理分级的加重,IgA、IgM、C3共沉积所占比率显著增多(P0.05)。结论 IgA肾病临床分型与病理分级有一定相关性,急性肾炎型、肾病综合征型及慢性肾炎型患儿病理损伤程度重,通过临床分型间接判断IgA肾病进展情况,对于指导临床治疗及判断疾病预后有一定临床价值。     

儿童IgA肾病的临床与病理分析

目的 探讨IgA肾病患儿临床表现和病理改变的关系及疾病转归.方法 分析30例IgA肾病患儿的临床和病理改变,病理分型采用改良Lee分型法,其中28例进行随访,4例重复肾活检.结果 临床表现孤立性血尿型10例,病理为Ⅰ、Ⅱ级;血尿和蛋白尿型11例,病理为Ⅰ～Ⅲ级;急性肾炎型2例,病理Ⅲ级;肾病综合征型7例,病理为Ⅱ～Ⅳ级,以Ⅱ、Ⅲ级为主.4例行重复肾活检,病理变化为改善、加重和无明显变化,但免疫复合物沉积均有加重.28例随访1年2个月～9年,其中9例预后不乐观;死亡1例;预后不良患儿7例治疗依从性差.结论 IgA肾病临床表现与病理有一定相关性,急性肾炎型、肾病综合征型患儿损伤重、预后欠佳,同时提示临床医师重视IgA肾病患儿随访和健康宣教,提高治疗依从性,以利疾病康复.     

强直性脊柱炎相关IgA肾病临床病理分析

目的了解强直性脊柱炎（AS）相关IgA肾病的临床病理特点。方法自1997年1月至2006年12月10年间在北京协和医院接受肾活检确诊为IgA肾病的AS患者10例，回顾性分析其临床及病理特点。结果男性9例，女性l例，平均年龄（28．6＋6．8）岁（16～53岁）。4例患者表现为无症状镜下血尿；6例表现反复血尿合并蛋白尿，其中2例有发作性肉眼血尿。平均尿蛋白量（24h）为（1．56±1．53）g（0．02-5．26g）。2例患者有血压升高。所有患者的血肌酐水平均在正常范围。光镜下，8例患者呈轻度系膜细胞增生，IgA肾病Lee氏分级均为Ⅰ或Ⅱ级；另外2例呈中重度系膜增生性改变，IgA肾病Lee氏分级分别为Ⅲ级和Ⅵ级。结论AS相关IgA肾病临床表现为隐匿性肾炎或慢性肾小球肾炎，病理改变以轻度系膜增生为主。     

成人轻微尿检异常IgA肾病患者的临床与病理分析

目的临床怀疑为IgA肾病的轻微尿检异常患者是否需要肾活检一直有争议,本研究通过分析轻微尿检异常的IgA肾病患者临床表现与病理表现之间是否存在相关性,旨在进一步探讨肾活检对单纯轻微尿检异常IgA肾病患者的临床意义。方法临床表现为单纯轻微尿检异常且肾活检明确诊断的患者91例中,筛选达到明确病理诊断标准的患者77例,其中病理确诊为IgA肾病的患者53例,依其临床表现不同分为蛋白尿合并血尿组、单纯血尿组和单纯蛋白尿组,并采用Lee分级和牛津分类两种IgA肾病病理评估方法对其肾脏病理严重程度进行评价,且分别评价三种不同临床表现IgA肾病患者之间肾脏病理严重程度评分分布有无不同。结果 77例明确病理诊断标准的患者中,被诊断为IgA肾病患者53例(占68.8%),其中蛋白尿并血尿者39例(占73.6%),单纯血尿者5例(占9.4%),单纯蛋白尿者9例(占17.0%);53例轻微尿检异常IgA肾病患者中,病理分级以LeeⅢ级为最多(29例,占54.7%),其他依次为Ⅱ级(14例,占26.4%)和Ⅰ级(5例,占9.4%),而病变严重的Ⅳ级和V级,分别为2例(占3.8%)和3例(占5.7%);不同临床表现IgA肾病患者之间肾脏病理无论Lee分级还是牛津分布均无统计学差异(均P0.05)。结论鉴于临床表现不能作为鉴别肾脏病变轻重的依据,因此,怀疑IgA肾病的单纯尿检异常患者,应在无禁忌症的前提下尽可能行肾活检以明确诊断,以利于及时调整治疗方案。     

210例IgA肾病肾间质血管病变的临床病理分析

目的 探讨肾间质血管病变在IgA肾病中的临床病理意义.方法 总结本院肾内科1999年1月～2010年6月肾活检证实210例IgA肾病患者临床病理资料,分析肾血管病变与患者临床表现、病理改变之间的关系.结果 210例IgA肾病中有各种肾血管病变者71例,占33.8％,139例患者无血管病变,占66.2％.两者相比,前者高血压发生率较高(73.2％vs24.5％,P＜0.05),血肌酐水平较高[(132.5±20.8)μmol/L vs (86.4±15.2)μmol/L,P＜0.05],肾小球滤过率较低[(59.7±9.2)ml/min vs (83.1±12.6) ml/min,P＜0.05],两组间差异有统计学意义.在IgA肾病各亚型中血管病变发生率分别为:Ⅰ型6.0％;Ⅱ型43.9％;Ⅲ型6.9％;Ⅳ型40.8％;V型93.1％.x2检验表明其不同分布的差异有统计学意义(P＜0.05),并提示随着IgA肾病的组织病理加重,肾间质血管病变增多.结论 肾间质血管病变在IgA肾病中较为常见,并与IgA肾病的临床表现及病理改变密切相关,提示肾间质血管病变是影响IgA肾病进展的重要因素.     

左肾静脉压迫综合征合并IgA肾病患者的临床分析

目的 通过分析6例左肾静脉压迫综合征合并IgA肾病患者的临床资料,提高临床医师对于左肾静脉压迫综合征合并IgA肾病的认识和诊治水平.方法 回顾性分析2012年1月至2014年1月我院的6例左肾静脉压迫综合征合并IgA肾病患者的临床资料.6例左肾静脉压迫综合征患者均由左肾静脉彩色多普勒诊断,其中1例患者同时行CT血管三维成像(computed tomography angiography,CTA)诊断;记录患者的性别、年龄、身高、体质量、尿常规、24 h尿蛋白定量、血常规、血肌酐、血白蛋白、血尿酸、补体C3、肾活检病理类型及影像学资料等.结果 6例患者均为男性,平均年龄(16.5±4.3)岁,平均体质量指数(body mass index,BMI)为17.8±1.3,以血尿、蛋白尿、腰痛为主要临床表现.病理级别为LeeⅠ级～LeeⅢ级;6例患者中1例患者为LeeⅠ级,4例患者为LeeⅡ级,1例患者为LeeⅢ级;1例患者有细胞性新月体形成(占肾小球总数比例的5.9％),1例患者有肾小球球性硬化(占肾小球总数比例的14.3)％.6例患者均有不同程度系膜增生(轻度～中度)及轻度肾小管萎缩、肾小管纤维化,所有患者均无间质血管炎;2例患者有间质灶性炎细胞浸润;免疫荧光检测,6例患者均有不同程度系膜区IgA沉积(++～+++)、IgG沉积(++)及补体C3沉积(+～++),6例患者均无系膜区IgM沉积.结论 对于BMI偏低的儿童和青少年出现血尿和(或)蛋白尿,行左肾静脉彩色多普勒检查和仰卧位/站立位尿液检查不仅有助于明确诊断,还有助于指导治疗,避免过度医疗.     

儿童无症状尿检异常IgA肾病的临床病理和预后分析

目的 探讨儿童无症状尿检异常的IgA肾病的临床病理特征和预后。 方法 对54例IgA肾病儿童的临床和病理特征进行分析。根据起病时有无临床症状分为无症状尿检异常组和有症状肾炎组。组织病理学分级参照Lee氏和Katafuchi氏半定量积分法。 结果 无症状尿检异常组18例，有症状肾炎组36例。有症状肾炎组尿蛋白量（24 h）明显高于无症状尿检异常组[（2.3±2.2） g比（0.4±0.3） g，P < 0.05]。无症状尿检异常的IgA肾病儿童表现为镜下血尿者，87％有尿微量白蛋白增高。无症状尿检异常IgA肾病患儿病理表现以Lee 氏Ⅰ~Ⅱ级为主，2例表现为Lee氏Ⅳ~Ⅴ级和 5例发生Katafuchi Ⅱ~Ⅲ级肾小管间质病变。有症状肾炎组Lee氏病理分级以Ⅱ~Ⅲ级为主，两者病理分级分布差异无统计学意义（P > 0.05）。全组患儿平均随访（26.9±8.8）月后，1例病理为Lee 氏Ⅴ级患儿进入终末期肾衰竭，其余患儿Scr均无升高1倍以上。 结论 无症状尿检异常的儿童IgA肾病虽临床症状轻微，但可出现病理损害严重的病例，并影响其预后。     

儿童孤立性血尿207例病理分析

目的：探讨小儿孤立性血尿的病理类型.方法：对207例符合孤立性血尿诊断标准的患儿行肾活检术,肾组织进行光镜、电镜及免疫荧光检查.结果：轻微病变72例（34.8%）;正常肾小球61例（29.5%）,其中局灶节段性肾小球透明样变性5例.IgA肾病36例（17.4%）;薄基底膜肾病21例（10.1%）,其中正常肾小球7例,伴轻微病变14例;系膜增生性肾小球肾炎13例（6.3%）,其中伴薄基底膜肾病2例;局灶增生性肾炎4例（1.9%）.结论：轻微病变与正常肾小球占第一位,IgA肾病是小儿表现为肉眼血尿的孤立性血尿的主要原因,但表现为孤立性血尿的IgA肾病病理变化相对较轻,为轻微病变或轻度系膜增生.所有病例均无新月体形成、肾小球硬化和小管间质受累.提示孤立性血尿患儿预后良好.     

不同CKD分期、大量蛋白尿型IgA肾病患者的临床、病理和预后分析

目的:分析不同慢性肾脏病(chronic kidney disease,CKD)分期的大量蛋白尿型IgA肾病患者的临床表现和病理改变,并随访观察患者的预后。方法:回顾性分析2012年01月~2016年12月CKD 1~5期大量蛋白尿型IgA肾病患者80例。比较CKD 3~5期大量蛋白尿型IgA肾病组(A组)及CKD 1~2期大量蛋白尿型IgA肾病组(B组)患者的临床和病理特点、治疗疗效及随访中肾存活率。结果:A组患者肾活检时肾功能较差,其血尿素氮(BUN)、血肌酐(Scr)、血尿酸(Sua)、高血压发病率均显著高于B组,血红蛋白、肾小球滤过率水平显著低于B组;肾脏病理上,A组患者活动性病变更明显,肾小管间质疾病及由于血管病变所致的肾损伤均重于B组,A组病理Lee氏分级均≥Ⅲ级,B组病理Lee氏分级均≤Ⅳ级。经糖皮质激素和/或免疫抑制剂治疗后,A组患者血白蛋白水平升高[(42.57±5.86)vs.(33.71±8.08)g/L,P0.01],肾小球滤过率升高[(54.69±16.35)vs.40.13±17.67)m L·min-1·1.73 m-2,P0.01],尿蛋白较治疗前显著下降[(2.77±1.98)vs.(6.59±4.17)g/24 h,P0.01],但有效率低于B组(55.56%vs.88.09%,,P0.01),治疗后A组患者的血肌酐、血尿素氮、尿蛋白水平仍高于B组[(2.77±1.98)vs.(1.19±1.07)g/24 h,P0.01],e GFR水平及肾存活率低于B组(84.23%vs.100.00%,P0.05)。结论:大量蛋白尿型IgA肾病患者中CKD 3~5期的患者与CKD 1~2期的患者相比,病理上活动性病变及慢性化病变均更明显,肾存活率更低;激素及免疫抑制剂治疗可使部分患者的尿蛋白减少,肾功能改善。CKD3~5期大量蛋白尿型IgA肾病患者仍需行肾活检以便明确诊断、及时治疗。     

123例原发性IgA肾病患者临床特点与病理分析

目的：探讨原发性IgA肾病患者临床表现、病理特点及其相关性。方法：回顾性总结分析123例经肾活检病理确诊为原发性IgA肾病的临床和病理资料。结果：123例IgA肾病患者在21岁～40岁年龄段发病率最高（占65.8%）;临床表现以发作性肉眼血尿最多见（占36.6%）;病理类型分级以Ⅱ级（56.1%）,Ⅲ级（20.3%）为主;病理类型与临床表现呈正相关（P〈0.01）;随着Lee氏病理分级程度的增高,血肌酐、血尿酸、血脂有不同程度的升高（P〈0.05）。结论：IgA肾病临床类型多样,其组织形态学改变轻重不一,宜尽早做肾活检以明确诊断,指导治疗。     

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.     

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.