下胫腓联合损伤对踝关节稳定性影响的生物力学研究

[目的]探讨下胫腓联合损伤对踝关节稳定性的生物力学影响。[方法]采用6例新鲜尸体标本,制作踝关节旋前外旋损伤模型,逐步离断下胫腓联合各韧带、骨间膜和三角韧带。对标本进行600 N轴向加载,同时对踝关节施加扭矩为5 Nm的外旋力。测量下胫腓联合不同程度损伤情况下,下胫腓联合的相对位移和踝关节外旋扭转角度。[结果]随着下胫腓联合韧带和三角韧带的序贯性离断,下胫腓联合的远端腓骨相对内外位移、前后位移、腓骨转角以及踝关节扭转角度呈逐渐增加趋势。[结论]下胫腓联合韧带维持踝关节稳定。在旋转稳定性方面,下胫腓后韧带的作用最为突出。下胫腓联合韧带离断后,再离断三角韧带,踝关节的稳定性进一步丢失。     

三角韧带与下胫腓联合韧带对踝关节稳定的生物力学影响

目的探讨三角韧带与下胫腓联合对踝关节稳定性的生物力学影响。方法采用6例新鲜踝关节标本,常规制成骨-韧带模型(标本可重复利用)。分为:A组:踝关节各韧带均完整;B组:三角韧带离断,下胫腓联合完整;C组:下胫腓联合离断,三角韧带完整;D组:下胫腓联合及三角韧带均离断;E组:锚钉修复三角韧带、螺钉固定下胫腓联合韧带组。对标本施加600 N轴向加载。分别测量三种体位(中立位、背伸10°位、跖屈20°位)在各种状态下胫距关节的接触面积、接触压力、压应力分布等变化。对比分析三角韧带及下胫腓联合韧带修复前后对踝关节稳定的作用。结果在三种体位下均可发现,随着下胫腓联合及三角韧带的离断,胫距关节接触面积逐渐减小,接触压力逐渐增大,与正常A组对比差异有统计学意义(P<0.05),压应力分布逐渐集中并有向外侧移位趋势;三角韧带与下胫腓联合修复前后的胫距关节的接触面积、接触压力等差异有统计学意义(P<0.05);修复后的胫距关节接触面积增大、接触压力减少,与正常组A组对比差异无统计学意义(P>0.05),压应力分布分散。结论三角韧带与下胫腓联合断裂后,距骨发生移位,胫距关节面接触面积、接触压力及压应力分布发生剧烈变化。目前骨锚钉修复三角韧带、螺钉固定下胫腓联合能获得即刻稳定,且其生物力学强度与正常组相似,推荐对三角韧带伴下胫腓联合损伤者行手术治疗以恢复其正常解剖关系。     

踝关节骨折

1踝关节局部解剖 1．1骨性结构 踝关节的骨性结构由胫骨远端关节面穹窿部、内外踩与距骨组成。主要包括距骨体马鞍形顶与胫骨远端关节面所构成的关节和下胫腓间的关节,另外距骨体两侧的关节面还与相应的内、外踝构成关节。胫骨远端关节面外侧宽,内侧略窄,后侧比前侧略低。外侧面为凹面,与腓骨相关节,有前后结节,前结节为下胫腓前韧带止点,后结节为下胫腓后韧带止点。胫骨远端内侧面向内下方延伸至内踝,内踝由前后丘组成,前丘较大,后丘较小,且该处有向内下走行的斜沟,内有胫后肌腱。距骨体几乎均被软骨覆盖,前宽后窄,外侧前后径比内侧长,容纳于内外踝所形成的踝穴中。踝关节背伸活动时,距骨体外旋,其前部进入踝穴,同时,腓骨外旋、后外侧移动以适应距骨的运动。而在踝关节跖屈活动时,距骨体内旋后部进入踝穴。     

螺钉固定与Tight-rope固定治疗下胫腓前联合损伤的初步有限元分析

目的 :建立下胫腓前联合损伤(anterior inferior tibiofibular syndesmosis injuries,AITSI)螺钉固定及Tightrope固定(TR)模型,比较其受力及位移情况,为临床诊治提供依据。方法 :选取1例正常人的踝关节CT图像建立3D模型。然后建立AITSI损伤模型,对损伤模型置入螺钉得到螺钉固定模型,使用Tight-rope固定得到TR模型。分析各模型单脚站立时的中立位、踝关节内旋以及外旋3种受力情况,观察胫腓骨及距骨关节面应力变化,以及胫腓骨远端位移情况。结果:AITSI导致胫腓骨及距骨关节面受力增加,胫腓骨位移增加。使用螺钉固定及TR均能有效减少AITSI导致的胫腓骨远端过度位移,但在螺钉固定模型中,胫腓骨位移明显小于正常模型,且胫腓骨远端及距骨关节面受力增大,螺钉受力集中。螺钉固定模型中的胫骨及腓骨最大受力为TR模型的1.3倍以上,距骨关节面接触力为1.8倍,螺钉固定模型中下胫腓前韧带胫骨附着点位移约为正常模型的0.6倍,而TR模型中该数据约为正常模型的1.1倍,但TR对于腓骨位移控制欠佳。结论:严重的下胫腓前联合损伤将改变踝关节受力及位移情况,应该行内固定治疗。下胫腓联合螺钉及TR都能有效地治疗下胫腓前联合分离,Tight-rope固定相较于螺钉固定在骨骼受力、踝关节微动及内固定物断裂方面具有优势,但存在腓骨旋转控制欠佳的劣势。伴有Weber C型踝关节骨折以及肥胖的患者更适合螺钉固定。     

后踝骨折与固定对踝关节旋转稳定性影响的定量评估

目的:定量评估后踝骨折与固定对踝关节旋转稳定性的影响。方法:选取膝上截肢新鲜尸体标本20个（10具）,解剖并测量下胫腓后韧带、下胫腓横韧带复合体在胫骨后方的附着范围;以韧带复合体在胫骨后方附着区为基础建立旋后外旋Ⅲ度后踝骨折合并下胫腓联合分离模型,经力学加载分析胫骨后方韧带附着区不同投影面积的后踝骨折和固定对下胫腓联合...     

踝关节跖屈、背屈运动的研究

目的:研究Pilon骨折在治疗中评价踝关节功能,诊断下胫腓联合分离、踝关节前后脱位的影像学依据。方法:35例正常成人,男21例(42踝),女14例(28踝);年龄21-48岁,平均31.6岁。踝关节常规摄正、侧位X线片;测量踝关节主动跖屈、背屈运动的最大角度,下胫腓联合间隙的宽度,胫骨外侧与腓骨的胫侧重叠影宽度,距骨踝关节面几何中心偏离胫骨中轴线的距离。结果:跖屈主动运动的最大角度,男(40.8°±3.1°),女(43.9°±4.8°);背屈主动运动的最大角度,男(27.6°±5.2°),女(26.5°±6.1°)。下胫腓联合间隙的宽度平均(3.2±0.5)mm。胫骨外侧与腓骨的胫侧重叠影宽度平均(6.9±2.2)mm。踝关节的跖屈下胫腓联合有逐渐变窄的变化,平均2 mm。距骨中心中轴距:男性跖屈最大值2.4 mm、背屈2.5 mm,女性跖屈最大值1.9 mm、背屈2.0 mm,最小值均为0 mm。结论:男女之间无论是背屈还是跖屈均无显著性差异(P>0.05),即踝关节在运动灵活性上无性别差异。踝关节主动跖屈、背屈运动的最大角度为Pilon骨折术中踝关节功能评定提供参考,下胫腓联合宽度>3.5 mm为下胫腓联合分离,胫骨外侧与腓骨的胫侧重叠影宽度<5.5 mm时,有下胫腓联合分离的可能。距骨中心中轴距>2 mm提示踝关节前后脱位。Pilon骨折在恢复骨折解剖复位的同时要注意这两个指标,对于恢复踝关节的侧方稳定、前后方向稳定有重要意义,能指导踝关节骨折治疗和康复。     

Weber-B型踝关节骨折修复下胫腓前韧带的生物力学研究

目的评价踝关节骨折修复下胫腓前韧带的生物力学稳定性。方法采集国人新鲜足标本一具,截取踝关节以上15cm下肢小腿横行截断,暴露下胫腓前韧带。载荷实现分级加载,选用小腿极限载荷（踝关节负重力为4.5BW）20%作为生理载荷,即以0、100、200、300、400、500N为分级载荷。万能材料试验机（WD-5）的加载速率为1.40 mm/min,以准静态方式加载,载荷施加于下肢胫腓骨上。并模拟足运动中立位、跖屈位（30°）、背屈位（20°）、旋后外旋位等四种生理运动状况,正常足及切除下胫腓前韧带测定踝关节的应力变化、距骨的移位变化及轴向刚度数据。结果标本在正常足及切断下胫腓前韧带的不同功能位上,踝关节的应力变化、距骨的移位变化及轴向刚度,统计学有显著性差异（P〈0.05）。结论在对内、外踝满意固定后,下胫腓前韧带的修复能更好恢复踝关节的生物弹性,最大限度恢复其原来的结构和功能,避免晚期创伤性关节炎的发生。     

外踝骨折后三角韧带完整性对踝关节稳定性影响的CT三维重建研究

目的 通过CT三维重建分析外踝骨折后三角韧带完整性对踝关节稳定性的影响.方法 选用18具成年人下肢标本,男11具,女7具;年龄55～79岁,平均68.2岁;均排除下肢外伤病史.将18具标本平均分为两组,每组9具.1组只切断下胫腓前韧带,即三角韧带完整组;2组同时切断下胫腓前韧带和内踝三角韧带,即三角韧带损伤组.每具标本于外踝尖近端3 cm处横行截断腓骨,通过标记的克氏针分别建立远端腓骨外旋5°、10°、15°、30°的畸形模型,并行钢板螺钉固定.每次建模后均行薄层CT扫描.将所有CT数据导入Mimics 10.01软件,通过自动密度识别及后期人工处理描绘下胫腓联合、踝穴及踝穴内距骨轮廓,运用软件建立下胫腓联合、踝穴、踝穴内距骨三维模型,并自动计算各模型体积.通过踝穴及踝穴内距骨体积相减,得到踝关节间隙体积.比较组间及组内不同旋转度数时各模型体积的变化,从而反映各病理模型对踝关节稳定性的影响.结果 随着旋转畸形度数增加,下胫腓联合及踝穴体积增大,而踝穴内距骨体积随之减小.在三角韧带完整组中不同旋转角度所致畸形模型比较,10°旋转畸形时下胫腓联合体积及踝关节间隙较正常开始出现显著性增大.在三角韧带损伤组中不同旋转角度所致畸形模型比较,5°旋转畸形即开始出现踝关节间隙及下胫腓体积较正常时显著性增大.结论 三角韧带完整性可影响外旋畸形时踩关节间隙的变化.当三角韧带完整时,10°外踝旋转畸形即可导致下胫腓联合及踝关节间隙显著性增大;而当合并三角韧带损伤时,5°旋转畸形即可出现踝关节间隙显著性增大,下胫腓联合显著性分离,踝关节不稳定.     

可吸收材料在固定下胫骨腓骨联合分离中的应用

下胫腓联合分离 (lowertibiafibularsyndesmoticdisruption)是在踝关节的损伤中, 由于外翻外旋等性质的外力作用所导致在胫骨腓骨下端间起联系作用的解剖结构的破坏; 踝关节因此失去了下胫腓联合各韧带的约束 -维持作用, 踝穴的稳定性及其对踝部活动的适应性随之丧失, 并在     

胫腓钩在伴下胫腓韧带损伤的踝关节骨折脱位中的应用

目的评价胫腓钩治疗伴下胫腓韧带损伤的踝关节骨折的疗效。方法2002年3月～2005年11月,应用胫腓钩治疗伴下胫腓韧带损伤的旋前型踝关节骨折脱位患者18例。根据术前X线片判断下胫腓联合损伤的程度,经术中探查证实；于下胫腓联合平面置钩,钩住腓骨,固定于胫骨上。取内固定的同时取胫腓钩。结果16例患者获得3个月～4年(平均17个月)随访,根据踝关节活动度、疼痛及X线情况评定疗效：优14例,良2例,未发现内固定物松动、断裂现象。结论胫腓钩在治疗合并下胫腓韧带损伤的踝关节骨折脱位中能有效地复位和固定,并能提供下胫腓微动关节的生理功能。     

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.