大鼠门静脉高压症及梗阻性黄疸时细菌移位与黄嘌呤脱氢酶和黄嘌呤氧化酶的关系

目的探讨大鼠门静脉高压症（porta; ju[ertemsopm,PH）及梗阻性黄疸（obstructive jaundioe,OJ）时,细菌移位（bacterial translocation,BT）与黄嘌呤氧化酶（xanthine oxidase,XO）、黄嘌呤脱氢酶（xanthine dehydrogenase,XD）之间的关系。方法将雄性SD大鼠60只随机分为对照组（A组）,胆总管结扎组（B组）和门静脉缩窄组（C组）,每组20只。术后第3周取肠系膜淋巴结、脾、肝组织及门静脉、腔静脉血细菌培养,测定门静脉压力（free portal pressure,FPP）,及肠XO,XD活性水平。结果B组及C组细菌移位率明显高于对照组（P〈0．01）,对照组为12％,B组和C组分别为28％和54％;B组和C组空肠XO水平活性明显高于对照组（P〈0．01）,B组和C组门静脉压力也较对照组升高。细菌移位率与XO活性成正相关（r=0．603）。XD活性水平无显著差异。结论门静脉高压症及梗阻性黄疸时可发生细菌移位,可能与肠黏膜屏障被破坏通透性增强有关,肠壁XO水平活性增强引起肠黏膜屏障通透性增高有助于细菌移位发生。     

猪门静脉血流阻断后细菌及内毒素移位的研究

目的：研究猪门静脉血流阻断后细菌及内毒素移位，进一步了解门静脉系统淤血对肠粘膜屏障功能的影响。方法：将健康荣昌种猪随机分为假手术组（SO）、门静脉阻断45min(PVC-45')、60min(PVC-60')组，在阻断前、复流前、复流后1h时相点，取肠系膜淋巴结作细菌培养及取门静血作内毒素检测。结果：PCV-45'、60’组细菌培养及LPS均明显高于未阻断组（SO组）（P＜0.05)。结论：门静脉阻断后引起的肠粘膜缺血/缺氧，是肠粘膜屏粘膜障功能障碍的直接原因，细菌移位和内毒素变化是肠粘膜屏障功能受损的表现。     

术前高压氧治疗对肝硬化门静脉高压症病人的影响

目的 研究术前高压氧（HBO）治疗对肝硬化门静脉高压病人的作用,并探讨其机理。方法 选取肝硬化门静脉高压病人12例接受HBO治疗。观察肝功指标、内毒素和NO水平、肠粘膜通透性、网状内皮系统功能及血流动力学指标在HBO前后变化;另设正常对照组8例,比较两组间肠粘膜通透性、网状内皮系统功能的差异。结果 （1）与正常秩序正常组相比,肝硬化组的肠粘膜通透性增高,而网状内皮系统吞噬功能降低,且内毒素与肠粘膜通透性呈正相关（r＝0．504,P＝0．012）。（2）HBO治疗后,病人的肝功改善;网状内皮系统功能恢复,内毒素、NO较前下降;脾脏厚度、门静脉宽度及门静脉血流量减少。（3）统计分析发现NO与内毒素、脾脏厚度及门静脉血流速度呈正相关（r1＝0．597,P1＝0．000;r2＝0．472,P2＝0．027;r3＝0．463,P3＝0．030）,与门静脉血流速度呈负相关（r＝－0．443,P＝0．030）。结论 HBO能改善肝硬化病人的肝脏功能,改善门静脉高压和高动力循环状态。其作用机理可能与改善肝脏供氧,增加网状内皮系统功能,减少血中内毒素及NO有关。     

肿瘤坏死因子对急性坏死性胰腺炎肠道屏障的影响及生长抑素的作用

目的 探讨肿瘤坏死因子（TNFα）在急性坏死性胰腺炎（ANP）肠道损伤中的作用及生长抑素对其肠道的保护作用。方法 制成大ANP模型,分为假手术组、ANP组及生长抑素治疗组。分别于术后6、12、24、48h测定血浆TNFα、内毒素、淀粉酶,并观察胰腺和回肠粘膜病理学及电镜超微结构及肠道细菌移位情况。结果ANP组血浆TNFα、内毒素、淀粉酶水平显著高于假手术组和治疗组,且以发病后12、24h最为明显（P<0.01-0.05）,血中细菌和肠系膜淋巴结（MLN）细菌移位率均为100％;肠粘膜上皮坏死脱落、血管扩张充血,固有膜中度水肿伴有炎性细胞浸润,电镜观察肠粘膜微绒毛长短不一、排列不整齐,脱落严重。生长抑素（SS）治疗组血浆 TNFα、内毒素、淀粉酶水平显著高于假手术组,也以发病后12、24h最为明显（P<0.01-0.05）,血中细菌和MLN细菌移位率为60％,光镜及电镜下肠粘膜也有明显病损,但程度较ANP组明显减轻。结论TNFα是导致ANP时肠道屏障损伤的重要因素,生长抑素能减轻ANP时肠道屏障的损伤。     

急性坏死性胰腺炎时肠屏障损害及肠源性细菌和内毒素移位的实验研究

目的 观察急性坏死性胰腺炎（ANP）时肠粘膜屏障的改变和肠源性细菌和内毒素移位。方法 将Wistar大鼠随机分为正常对照组（n=6)、假手术组（n=30)和ANP组（n=39)。采用人工胆汁胰管逆行灌注法制作ANP模型。观察胰腺、小肠病理改变和小肠粘膜上皮细胞间紧密连接（冷冻蚀刻电镜）变化。动态测定血浆D-乳酸、内毒素水平,以及腹腔脏器细菌移位率。结果 ANP后小肠粘膜损伤,皮皮细胞间紧密连接破坏甚至消失,血浆D-乳酸水平上升,发病早期即出现内毒素血症;ANP发生后72h脏器细菌移位率达到59.5%。结论 ANP早期肠粘膜屏障功能受损。导致肠道细菌和内毒素移位,成为全身炎症反应和胰腺继发感染的根源。     

腹腔感染实验大鼠肠粘膜屏障功能的变化及机理

目的探讨实验大鼠腹腔感染时肠粘膜屏障功能变化及其发病机理。方法在盲肠结扎加穿孔（ＣＬＰ）模型上,观察肠粘膜通透性、肠粘膜血流量、血浆内毒素、肠道荧光标记菌示踪以及肠组织血小板活化因子（ＰＡＦ）、磷脂酶Ａ２（ＰＬＡ２）和丙二醛（ＭＤＡ）的变化。结果腹腔感染组比对照组肠粘膜通透性和血浆内毒素水平明显升高;肠道荧光标记菌大量移位于肠外器官。肠粘膜血流量明显降低。肠组织ＰＡＦ、ＰＬＡ２和ＭＤＡ水平明显升高。应用ＰＡＦ拮抗剂ＷＥＢ２１７０治疗能明显减轻肠粘膜损害,有效降低肠道细菌移位率和血浆内毒素水平。结论腹腔感染时有肠粘膜屏障功能严重受损和肠源性感染发生,而ＰＡＦ是导致这一病理生理改变的重要因素之一     

中药清胰汤对犬急性坏死性胰腺炎肠粘膜损伤修复的影响

为观察中药清胰腺对急性坏死性胰腺炎（ＡＮＰ）犬肠粘膜损伤修复的作用，经主胰管注入牛磺胆酸钠和胰蛋白酶复制犬ＡＮＰ模型，观察ＡＮＰ时及中药清胰汤治疗后肠粘膜组织结构的变化，肠组织蛋白、丙二醛（ＭＤＡ）含量及二胺氧化酶活性（ＤＡＯ）改变，肠通透性变化，检测血中内毒素水平，并做脏器细胞培养。结果发现，经中药清胰汤治疗后，ＡＮＰ犬的肠粘膜损害明显减轻，肠粘膜绒毛宽度、高度和面积显著增加，肠组织蛋白含量增加，肠通透性显著下降，血中内毒素水平下降１～２倍，脏器细菌移位率减少５０％。本实验结果提示：中药清胰汤能显著减轻犬ＡＮＰ时肠粘膜的损伤，保护肠屏障功能，减少肠道内毒素和细菌移位     

门静脉高压症病人肠道通透性、NO和内毒素的研究

目的　观察门静脉高压症病人的门静脉压力、肠道通透性、NO和内毒素水平 ;并分析它们之间的相互关系。方法　门静脉高压症病人 2 0例 ,分别检测肠道通透性、门静脉压力和外周血中NO和内毒素浓度。另有 2 0位健康志愿者作对照。结果　门静脉高压症病人较健康志愿者的肠道通透性 (0 132± 0 110vs 0 0 32± 0 0 18,P <0 0 1) ,外周血的NO浓度 (38 77± 13 71vs 2 1 77±3 0 1μmol/L ,P <0 0 0 1)和内毒素浓度 (0 5 7± 0 18vs 0 11± 0 0 5EU/ml,P <0 0 0 1)均非常明显的升高。研究还发现门静脉压力和这三者均有显著相关性 (r >0 45 ,P <0 0 5 ) ,另外肠道通透性与内毒素浓度 (r=0 5 2 9,P <0 0 5 )也存在相关性 ,而与NO浓度则无相关性 ;内毒素和NO之间没有发现相关性。结论　研究表明门静脉高压症病人肠道通透性、NO和内毒素水平显著升高。门静脉压力和这三者的显著相关说明门静脉压力升高是导致肠道通透性升高的直接因素 ,而内毒素和NO的升高维持了门静脉的高动力循环。     

银杏内酯B对急性胆管炎大鼠细菌移位的作用

目的 观察银杏内酯B对重症胆管炎大鼠细菌移位的作用。方法 取Wistar大鼠，分3组：假手术组、感染组、治疗组，各12只。术前用荧光素标记大肠杆菌给鼠灌胃后，在感染组、治疗组制成急性胆管炎模型。假手术组只游离胆管。术后30min感染组腹腔内注射二甲亚砜，治疗组注射银杏内酯B。6h后活杀取肠系膜淋巴结和肝制成为10％组织匀浆在荧光显微镜下细菌计数。同时光镜下观察小肠和肝病理形态变化。另选取12只大鼠，用4％镧行肠系膜上静脉灌注随后用戊二醛灌注内固定，取该段小肠处理后在电镜观察镧在肠粘膜屏障的通透性。结果 治疗组各细菌移位数较感染组均显著减少(P＜0．01)。肠粘膜和肝病理损害也明显轻(P＜0．05)。电镜下，治疗组镧在肠粘膜通透性下降。结论 银杏内酯B可以减少急性胆管炎时肠道细菌向肠系膜淋巴结和远位器官的移位，并对肠粘膜屏障和肝等组织器官有保护作用。     

谷氨酰胺双肽保护肠粘膜屏障

传统的肠外营养和化疗药应激可导致肠粘膜形态及屏障功能障碍。为研究腹腔注射５－ＦＵ后谷氨酰胺双肽对肠粘膜形态及屏障功能的影响，作者将大鼠随机分成两组。对照组（ｎ＝１０）接受传统肠外营养液。双肽组（ｎ＝１０）接受传统肠外营养液加３％谷氨酰胺双肽，胃肠外营养维持７天；第４天腹腔注射５－ＦＵ，第３、７天测定肠粘膜通透性，第８天处死，测氨基酸谱、肠粘膜形态及细菌移位。结果：双肽组较对照组体重丢失少（Ｐ＜０．０５）。双肽组血浆谷氨酰胺浓度、空肠粘膜厚度和绒毛高度均高于对照组（Ｐ＜０．０５）。双肽组肠系膜淋巴结细菌移位率低于对照组（分别为３０％和９０％，Ｐ＜０．０５）。对照组和双肽组术后第３天（即化疗前）肠粘膜通透性无差异。乳果糖／甘露醇（Ｌ／Ｍ）分别为０．０２６±０．００６和０．０２２±０．００３。用５－ＦＵ后第３天（即第７天）对照组肠粘膜通透性明显升高。Ｌ／Ｍ为０．０４２±０．００５（Ｐ＜０．０５）。但双肽组Ｌ／Ｍ基本维持不变０．０２９±０．００２。作者认为：谷氨酰胺双肽强化的肠外营养对腹腔注射５－ＦＵ的大鼠，可维持小肠粘膜形态及屏障功能，减轻肠道细菌移位和肠粘膜通透性的升高。     

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.