氯胺酮减轻雷米芬太尼致术后痛觉过敏的半数有效量

目的测定氯胺酮减轻雷米芬太尼致术后痛觉过敏的半数有效量(ED50)。方法选择48例ASAⅠ或Ⅱ级择期全麻腹腔镜下行胆囊切除术的成年患者,用点斜法测定氯胺酮减轻雷米芬太尼致术后痛觉过敏的ED50。结果氯胺酮减轻雷米芬太尼致术后痛觉过敏的ED50为0.23mg/kg(95%可信区间:0.08～0.39mg/kg),ED95为0.68mg/kg(95%可信区间:0.41～1.92mg/kg)。结论氯胺酮减轻雷米芬太尼致术后痛觉过敏的ED50为0.23mg/kg。     

纳布啡抑制无痛人工流产术后宫缩痛的半数有效剂量

目的采用改良序贯法测定纳布啡抑制无痛人工流产术后宫缩痛的半数有效剂量(ED 50)。方法择期行无痛人工流产术患者28例,年龄18~35岁,BMI 18.5~28.0 kg/m²,ASAⅠ或Ⅱ级。纳布啡初始剂量为0.1 mg/kg,静注完毕后3 min静注丙泊酚2 mg/kg,待睫毛反射消失后行无痛人工流产术,发生体动反应时,追加丙泊酚0.5 mg/kg。术后若宫缩痛阳性,则下一例增加纳布啡剂量;反之,则降低剂量,按0.01 mg/kg梯度增减。宫缩痛阳性标准:术后20 min内出现VAS疼痛评分>3分。在研究过程中,出现7个宫缩痛阳性转阴性拐点则终止研究。采用Probit法计算纳布啡抑制宫缩痛的ED₅₀、ED₉₅及相应95%可信区间(CI)。记录呼吸暂停、低氧血症、心动过缓、低血压及恶心呕吐等发生情况。结果纳布啡抑制无痛人工流产术后宫缩痛的ED 50及其95%CI为0.099(0.090~0.107)mg/kg,ED 95及其95%CI为0.117(0.108~0.173)mg/kg。所有患者未发生呼吸暂停、低氧血症及呕吐。1例发生头晕,1例轻度恶心。结论丙泊酚静脉麻醉时,纳布啡抑制无痛人工流产术宫缩痛的ED 50为0.099 mg/kg。     

阿芬太尼复合环泊酚在无痛取卵术中的半数有效量及95%有效量

目的探讨阿芬太尼复合环泊酚用于无痛取卵术的ED50及95%有效剂量(95% effective dose, ED95)。方法纳入拟行无痛取卵术的患者, 年龄21～40岁, BMI 18.5～28.3 kg/m2, ASA分级Ⅰ、Ⅱ级。设置阿芬太尼初始剂量4 μg/kg, 环泊酚0.4 mg/kg, 采用改良序贯法确定下一例患者阿芬太尼给药剂量。记录患者术中不良反应(低血压、低氧血症、心动过缓、恶心呕吐、头晕)发生情况, 采用概率单位Probit回归分析法计算阿芬太尼的ED50、ED95及其95%CI。结果阿芬太尼复合环泊酚用于无痛取卵术的ED50、ED95及其95%CI分别为3.8(3.2～4.2)μg/kg、4.6(4.2～9.7)μg/kg。术中有4例患者出现低血压, 3例患者发生低氧血症, 1例患者出现头晕, 无患者发生恶心呕吐和心动过缓。结论阿芬太尼复合环泊酚(0.4 mg/kg)用于无痛取卵术的ED50、ED95分别为3.8 μg/kg和4.6 μg/kg。     

芬太尼抑制七氟醚复合瑞芬太尼麻醉恢复期间患儿躁动的药效学

目的 探讨芬太尼抑制七氟醚复合瑞芬太尼麻醉恢复期间患儿躁动的药效学.方法 择期拟行鼻内镜下增殖体刮除术的息儿26例,年龄5～8岁,体重15～30 kg,ASA Ⅰ或Ⅱ级.麻醉诱导:吸入8%七氟醚(氧流量6 L/min),静脉注射瑞芬太尼1 μg/kg(经30 s注射完),气管插管后行机械通气,随后静脉注射芬太尼抑制麻醉恢复期间患儿躁动,采用改良的序贯法确定静脉注射芬太尼的剂量.第1例患儿静脉注射芬太尼的剂量为4μg/kg,相邻剂量差值为0.5μg/kg,以患儿苏醒后易激惹且难以安慰作为判断躁动发生的标准.麻醉维持:吸人2%七氟醚(氧流量1 L/min),静脉输注瑞芬太尼0.2μg·kg-1·min-1.术毕停用七氟醚和瑞芬太尼,带气管导管回麻醉恢复室,待患儿苏醒.记录术后4h内患儿躁动、恶心、呕吐、呼吸抑制等的发生情况及苏醒时间.计算芬太尼抑制50%、95%患儿七氟醚复合瑞芬太尼麻醉恢复期间躁动的剂量(ED50、ED95)及其95%可信区间.结果 芬太尼抑制七氟醚复合瑞芬太尼麻醉恢复期间患儿躁动的ED50及其95%可信区间为3.01(2.52～3.40)μg/kg,En95及其95%可信区间为3.81(3.41～6.22)μg/kg.术后4h内未发生明显恶心、呕吐及呼吸抑制.苏醒时间(11.3±2.6)min.结论 芬太尼抑制七氟醚复合瑞芬太尼麻醉恢复期间患儿躁动的ED50为3.01μg/kg,ED95为3.81μg/kg.     

雷米芬太尼抑制扩宫颈体动反应的半数有效浓度

目的 测定复合靶控输注丙泊酚时雷米芬太尼抑制人工流产术中扩宫颈时体动反应的半数有效效应室靶浓度.方法 40例择期行人工流产术的早孕病人,同时靶控输注丙泊酚和雷米芬太尼,固定丙泊酚的效应室浓度(3μg/ml),雷米芬太尼按序贯法给予,相邻效应室靶浓度之间比率为1.2.输注3 min后开始手术.记录病人有无体动反应.结果 抑制人工流产术扩宫颈时体动反应的雷米芬太尼Ce50为2.24 ng/ml,95%可信区间为1.97～2.55 ng/ml.结论 在复合靶控输注3μg/ml丙泊酚时,雷米芬太尼抑制人工流产术扩宫颈的体动反应的半数有效效应室靶浓度为2.24ng/ml.     

老年和成年患者依托咪酯诱导时雷米芬太尼抑制气管插管反应的半数有效血浆浓度

目的测定老年和成年患者依托咪酯诱导时雷米芬太尼抑制气管插管反应的半数有效血浆浓度(Cp50)。方法择期全麻手术患者40例,ASAⅠ或Ⅱ级,年龄19~80岁,体重指数20~30kg/m2,按年龄分为青壮年组(19~64岁)和老年组(65~80岁),每组20例。雷米芬太尼靶控输注5min后,静脉注射0.3mg/kg的依托咪酯,患者意识消失后给予罗库溴铵行气管插管。雷米芬太尼的血浆靶浓度按序贯法确定,相邻血浆靶浓度之间的比率为1.2。结果0.3mg/kg依托咪酯诱导时,老年组和青壮年组雷米芬太尼抑制气管插管的Cp50分别为4.11μg/L和3.37μg/L,95%可信区间分别为3.90~4.34μg/L和3.02~3.75μg/L。结论老年和青壮年患者在复合0.3mg/kg的依托咪酯行麻醉诱导时,雷米芬太尼抑制气管插管反应的Cp50分别为4.11g/L和3.37μg/L。     

右美托咪定滴鼻用于患儿CT检查中镇静的ED50和ED95

目的测定右美托咪定滴鼻用于患儿CT检查中镇静的ED50和ED95。方法随机选择ASAⅠ级接受CT检查需镇静的4~6岁患儿29例,CT检查前30~45min经鼻滴入右美托咪定,剂量采用改良序贯法确定,初始剂量为2.5μg/kg,根据上一例患儿检查中镇静效果,下一例患儿增加或减少0.5μg/kg。用概率单位回归分析法计算出右美托咪定有效镇静的ED50、ED95及相应的95%可信区间(95%CI)。结果右美托咪定滴鼻镇静的ED50为2.09μg/kg,95%CI为1.69~2.45μg/kg;相应的ED95为2.94μg/kg,95%CI为2.54~5.05μg/kg。结论 4~6岁患儿CT检查中滴鼻给予右美托咪定镇静的ED50和ED95分别为2.09μg/kg和2.94μg/kg。     

鞘内注射吗啡用于胸腔镜肺叶切除术患者术后镇痛的半数有效剂量

目的 探讨鞘内注射吗啡（ITM）用于胸腔镜肺叶切除术患者术后镇痛的半数有效剂量（ED50）。
方法 选择拟行全麻下胸腔镜肺叶切除术患者22例,年龄35～64岁,BMI 18～30 kg/m²,ASA Ⅰ或Ⅱ级。所有患者于术前在L_2-3间隙行蛛网膜下腔穿刺。患者鞘内吗啡的初始给药剂量为5 μg/kg,相邻药物剂量比值为1∶1.1,剂量梯度依次为5.00、4.55、4.14、3.76、3.42、3.11 μg/kg。根据上一例患者术后镇痛效果,下一例患者上升或下降一个剂量梯度。术后镇痛有效标准：若术后6、12、24、48 h活动时VAS疼痛评分均≤3分,则认为术后镇痛有效;若任一时刻活动时VAS疼痛评分＞3分,则认为镇痛无效。采用Probit法计算ED50、ED95及其95%可信区间（CI）。记录呼吸抑制、恶心呕吐、皮肤瘙痒、尿潴留等不良反应的发生情况。
结果 ITM用于胸腔镜肺叶切除术的ED50为3.468 μg/kg（95%CI 2.926～3.782 μg/kg）,ED95为4.037 μg/kg（95%CI 3.746～7.127 μg/kg）。有2例（9%）出现皮肤轻微瘙痒,3例（14%）出现恶心呕吐,未观察到其他不良反应发生。
结论 鞘内注射吗啡用于胸腔镜肺叶切除术的ED50为3.468 μg/kg（95%CI 2.926～3.782 μg/kg）。     

复合丙泊酚时阿芬太尼抑制患儿无痛皮肤磨削术中体动反应的半数有效剂量

目的 探讨复合丙泊酚时阿芬太尼抑制患儿无痛皮肤磨削术中体动反应的半数有效剂量（ED₅₀）。
方法 选择2021年7—11月择期行无痛皮肤磨削术患儿24例，男11例，女13例，年龄5～10岁，BMI 12～20 kg/m²，ASA Ⅰ或Ⅱ级。所有患儿均给予丙泊酚2 mg/kg复合阿芬太尼静脉麻醉。采用Dixon序贯法进行研究，阿芬太尼初始剂量10 μg/kg，下一例患儿剂量由上一例患儿体动反应决定，若术中体动反应阳性，下一例患儿阿芬太尼剂量增加1 μg/kg；若术中体动反应阴性，则下一例患儿阿芬太尼剂量减少1 μg/kg，重复此过程直到出现7个拐点终止研究。采用Probit法计算阿芬太尼的ED₅₀、95%有效剂量（ED₉₅）及其95%可信区间（CI）。
结果 复合丙泊酚时阿芬太尼抑制体动反应的ED₅₀为9.58 μg/kg（95%CI 8.97～10.21 μg/kg），ED₉₅为10.74 μg/kg（95%CI 10.12～14.01 μg/kg）。
结论 复合丙泊酚2 mg/kg时阿芬太尼用于患儿无痛皮肤磨削术的ED₅₀为9.58 μg/kg(95%CI 8.97~10.21 μg/kg)。     

雷米芬太尼呼吸抑制的半数有效血浆浓度的临床研究

目的测定靶控输注雷米芬太尼引起呼吸抑制的半数有效血浆浓度(Cp50)。方法20例择期手术病人行椎管内阻滞。按序贯法给予雷米芬太尼靶控输注20min,相邻血浆靶浓度之间比率为1·5。测定RR、SpO2、PETCO2及动脉血气。结果雷米芬太尼引起呼吸抑制的Cp50为1·8μg/L,95%可信区间为1·5~2·1μg/L。结论雷米芬太尼引起呼吸抑制的Cp50为1·8μg/L。     

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.