胸腰椎骨折患者经伤椎置钉与跨节段椎弓根螺钉内固定治疗的临床效果比较

[目的]比较胸腰椎骨折患者经伤椎置钉与跨节段椎弓根螺钉内固定治疗的临床效果。[方法]选择本院2012年1月~2013年12月间收治的96例胸腰椎单一椎体骨折患者,随机数字法将其分为2组,每组48例。伤椎置钉组给予伤椎置钉内固定术,跨节段组给予跨节段椎弓根螺钉内固定术。统计两组手术时间、出血量;术后随访2~3年,对患者视觉模拟评分(VAS)、Cobb角、伤椎前缘高度压缩率、日本骨科协会(JOA)评分变化进行观察。[结果]两组在手术时间、出血量方面差异无统计学意义(P>0.05)。术后1周、1年时两组VAS、Cobb角较术前均显著改善(P<0.05),但两组间差异无统计学意义(P>0.05)。术后1周、1年时两组伤椎前缘高度压缩率较术前均显著减少(P<0.05),且伤椎置钉组伤椎前缘高度压缩率明显低于跨节段组(P<0.05)。术后1年两组JOA评分较术前均显著升高(P<0.05);但两组间差异无统计学意义(P>0.05)。[结论]经伤椎置钉椎弓根螺钉内固定术可有效治疗胸腰椎骨折,具有内固定牢固、矫正效果好的优点。     

经椎弓根及伤椎内固定治疗胸腰段椎体骨折体会

目的总结跨伤椎和经伤椎椎弓根置钉复位固定治疗胸腰椎骨折的临床效果。方法 2003年1月至2010年4月我们收治126例胸腰段椎体骨折,年龄23～61岁。采用后路减压椎管成形椎弓根内固定植骨融合术,跨伤椎固定97例,经伤椎置钉固定29例。结果所有伤椎椎体前缘高度与后缘高度（PVH）的比值由术前（0.34±0.11）增加到术后（0.84±0.10）;矢状位后凸Cobb角由术前（25.46±2.59）°减少至术后（12.12±1.23）°。跨椎体组伤椎椎体前缘高度与后缘高度的比值由术前（0.36±0.12）增加到术后（0.83±0.11）;矢状位后凸Cobb角由术前（25.40±2.50）°减少至术后（12.2±1.21）°。经伤椎组伤椎椎体前缘高度与后缘高度的比值由术前（0.345±0.11）增加到术后（0.882±0.12）,矢状位后凸Cobb角由术前（25.43±2.53）°减少至术后（10.17±1.21）°。两组间结果对比显示经伤椎组椎体高度恢复和矫正后凸畸形效果好于跨椎体组（P〈0.01）,末次随访显示跨椎体组矫正角度有所丢失。跨伤椎组发生断钉3例,松动2例,经伤椎椎弓根螺钉内固定组无松动,无断裂、断棒。结论椎弓根钉固定是治疗胸腰椎骨折的一种有效方法,经伤椎固定可以有效维持脊柱复位效果。     

终板破裂程度对胸腰椎骨折椎弓根螺钉内固定手术预后的影响

目的研究终板破裂程度对胸腰椎骨折椎弓根螺钉内固定预后的影响。方法纳入2013年1月~2016年6月治疗的145例胸腰椎骨折合并终板破裂患者,根据CT矢状位重建终板破裂横面积或终板最低点下陷高度50%、≥50%设为轻度破裂组(83例)与中重度破裂组(62例)。采用后路开放式或经皮椎弓根螺钉内固定治疗,随访26~46个月,记录术前、术后1个月、6个月、末次随访时的伤椎高度压缩率、Cobb角以及疼痛视觉模拟评分(VAS)。结果两组术后1个月、6个月、末次随访的伤椎高度压缩率、Cobb角以及疼痛VAS评分均显著低于术前(P0.05);末次随访时,轻度破裂组的伤椎高度压缩率、Cobb角以及疼痛VAS评分均显著低于中重度破裂组,差异有统计学意义(P0.05)。结论终板破裂程度对胸腰椎骨折行椎弓根螺钉内固定手术的早期矫正效果以及疼痛改善程度无明显影响,终板破裂程度高者远期可加重椎体高度丢失。     

经伤椎植入固定螺钉和万向螺钉对胸腰椎骨折手术疗效的影响

目的 探讨经伤椎植入固定螺钉和万向螺钉对胸腰椎骨折行后路钉棒内固定手术疗效的影响。方法 纳入2014年4月-2017年6月收治的147例胸腰椎骨折患者,按照伤椎固定螺钉的不同,分为固定螺钉组(68例)和万向螺钉组(79例)。所有患者均于术前、术后1周及随访12个月时进行X线和CT检查,测定并比较两组间的伤椎前缘高度及Cobb角变化。结果所有患者均获随访1-3年(平均1.6年),两组患者术前椎体压缩率及Cobb角之间无显著差异(P0.05);相较于术后1周,固定螺钉组术后12个月的椎体压缩率及Cobb角均无显著丢失(P0.05),而万向螺钉组术后12个月的上述指标均出现明显丢失现象(P0.05);术后12个月时,两组患者的椎体压缩率及Cobb角差异有统计学意义(P0.05)。结论 相较于万向螺钉,选用固定螺钉有助于恢复伤椎形态、维持术后的椎体高度和减少Cobb角丢失。     

后路短节段内固定结合伤椎椎弓根植骨治疗胸腰椎骨折的临床观察

目的观察后路短节段内固定结合伤椎椎弓根植骨治疗胸腰椎骨折的临床疗效。方法胸腰椎骨折患者56例,随机分为两组:伤椎植骨组30例,采用后路短节段固定结合伤椎椎弓根植骨术治疗;单纯固定组26例,采用单纯后路短节段固定术治疗。比较两组患者术后椎体前缘高度恢复率、Cobb角以及神经功能Frankel分级评分变化。结果 56例患者均获随访,时间12～20月,平均(15.8±3.7)月。所有患者均未出现伤口感染、断钉等并发症。组内比较,两组术后伤椎椎体前缘高度压缩率、Cobb角较术前差异均有统计学意义(P<0.01);组间比较,术前及术后1周时两组椎体前缘高度压缩率及Cobb角差异均无统计学意义(P>0.05),而末次随访时两组间差异有统计学意义(P<0.05),伤椎植骨组明显优于单纯固定组。两组术后神经功能Frankel分级评分无统计学差异(P>0.05)。结论后路短节段椎弓根内固定结合伤椎椎弓根植骨治疗胸腰椎骨折疗效确切,能减少椎体高度丢失以及后凸畸形的复发加重,降低内固定并发症的发生率,且操作安全,值得临床推广。     

两种不同术式治疗胸腰椎骨折的对比研究

目的探讨微创经皮与开放短节段椎弓根螺钉固定结合伤椎内植骨治疗胸腰椎骨折的临床疗效。方法回顾性分析2013年1月至2015年1月收治的60例胸腰椎爆裂或压缩骨折患者的临床资料,其中30例采用微创经皮椎弓根螺钉固定结合伤椎内植骨治疗,30例采用开放短节段椎弓根螺钉固定结合伤椎内植骨治疗,观察两组患者的手术时间、术中出血量,比较两组患者手术前后疼痛视觉模拟评分(visual analog scale,VAS)、伤椎前缘高度压缩率、椎体Cobb角情况。结果 60例患者均获随访,随访时间8~18个月,平均12.8个月。所有患者术后切口均Ⅰ期愈合,无感染、深静脉血栓形成等并发症发生,无内固定物松动、断裂。微创组手术时间、术中出血量较开放组明显减少,差异有统计学意义(P0.05)。两组患者术后1周、末次随访VAS评分、伤椎前缘高度压缩率及椎体Cobb角较术前均有改善,差异有统计学意义(P0.05);术后同组内不同时间点伤椎前缘高度压缩率、椎体Cobb角比较差异无统计学意义(P0.05);术后两组患者同一时间点伤椎前缘高度压缩率、椎体Cobb角比较差异无统计学意义(P0.05)。微创组术后1周疼痛缓解较开放组明显,差异有统计学意义(P0.05);末次随访时两组患者疼痛程度相当,差异无统计学意义(P0.05)。结论微创经皮椎弓根螺钉固定结合伤椎内植骨治疗胸腰椎骨折具有出血少、创伤小、用时少等优点,能有效恢复并维持伤椎高度,矫正脊柱后凸畸形,对伤椎高度恢复及脊柱后凸畸形矫正与开放手术相当,短期内对术后患者疼痛缓解优于开放手术。     

经伤椎置钉椎弓根螺钉内固定治疗胸腰椎骨折临床体会

目的探讨同时经伤椎置钉椎弓根螺钉系统固定治疗胸腰椎骨折的可行性和有效性。方法自2008年7月至2011年1月．采用椎弓根螺钉系统同时经伤椎置钉固定治疗胸腰椎骨折24例,均为单椎体骨折,采用5钉或6钉三椎体固定。患者术前、术后即刻和术后12个月随访均行X线及CT检查,测量比较Cobb角、伤椎前缘压缩率、椎管占位率及神经功能Frankel分级。结果随访12～27个月,平均15．5个月。椎体前缘高度、Cobb角、椎管占位以及Frankel分级均较术前有显著改善。结论同时经伤椎置钌椎弓根螺钉系统固定治疗胸腰椎骨折是一种可行而有效的方法。     

微创经皮椎弓根钉内固定联合伤椎椎体植骨治疗胸腰椎骨折的疗效分析

目的探讨微创经皮椎弓根钉内固定联合伤椎椎体植骨治疗胸腰椎骨折的临床疗效。方法回顾性分析自2013-01—2015-01采用微创经皮椎弓根钉内固定联合伤椎椎体植骨治疗的32例胸腰椎骨折。观察术前、术后1周、末次随访时伤椎前缘高度压缩率、椎体Cobb角、疼痛视觉模拟评分(VAS)。结果本组手术时间(72.5±9.2)min,术中出血量(50.4±12.3)ml。32例均获得随访6~18个月,平均12.4个月。切口均一期愈合,无椎弓根钉松动、断裂,无脊髓神经损伤。术后1周、末次随访时伤椎前缘高度压缩率、椎体Cobb角及VAS评分较术前明显改善,差异有统计学意义(P0.05)。术后1周与末次随访3项指标比较差异无统计学意义(P0.05)。结论微创经皮椎弓根钉内固定联合伤椎椎体植骨治疗胸腰椎骨折具有创伤小、出血少、固定可靠等优点,能有效恢复并维持伤椎高度,矫正脊柱后凸畸形,短期疗效确切。     

经伤椎双节段与跨伤椎短节段固定治疗胸腰椎骨折3年以上随访结果

目的比较经伤椎双节段固定与跨伤椎短节段固定治疗胸腰椎骨折的中期随访结果。方法对63例经伤椎双节段与跨伤椎短节段固定治疗并获得3年以上随访的胸腰椎骨折患者的资料进行分析。比较两组患者的手术时间及术中出血量;测量术前、术后3 d和末次随访时伤椎及其上下相邻正常椎体的前缘高度、伤椎后凸Cobb角,比较两组的椎体前缘高度比、末次随访矫正度丢失情况。结果跨伤椎短节段固定组的手术时间和术中出血量明显少于经伤椎双节段固定组(P0.05)。患者均获得随访,时间37~77(52.8±11.5)个月。末次随访时患者满意率:经伤椎双节段固定组为90.3%、跨伤椎短节段固定组患者为84.4%(P0.05)。术后两组患者椎体前缘高度及Cobb角较术前均显著恢复(P0.05)。末次随访时,经伤椎双节段固定组对椎体前缘高度和矢状面Cobb角的保持优于跨伤椎短节段固定组(P0.05)。结论经伤椎双节段固定术及跨伤椎短节段固定术都能较好地恢复胸腰椎骨折的椎体高度和Cobb角。经伤椎双节段固定术对术后矫正度的保持优于跨伤椎短节段固定术,但手术时间相对较长、出血量相对较多。     

经椎间孔椎体间植骨融合结合伤椎椎弓根螺钉内固定治疗严重胸腰椎骨折

目的 探讨经椎间孔椎体间植骨融合结合伤椎椎弓根螺钉内固定治疗严重胸腰椎骨折的临床疗效.方法 对15例严重胸腰椎骨折患者经椎间孔椎体间植骨、伤椎椎弓根螺钉内固定治疗,术后进行临床和影像学随访.结果 15例均获得随访,时间6～12个月.患者骨折椎体高度均明显恢复,伤椎椎体高度比:术前为49.2%±15.7%,术后3 d及3个月分别为99.2%±4.5%、91.1%±5.8%,与术前比较差异均有统计学意义(P＜0.05).Cobb角:术前为32.3°±9.6°,术后3 d和术后3个月分别为3.5°±3.4°、3.9°±3.7°,与术前比较差异均有统计学意义(P＜0.05).神经功能按ASIA分级,除5例A级患者无恢复外,其余较术前均有1级或1级以上的恢复.结论 经椎间孔椎体间植骨融合结合伤椎椎弓根螺钉内固定是治疗严重胸腰椎骨折的良好方法.     

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.