镜下喙突免钻孔喙锁韧带重建术

[目的]介绍镜下喙突免钻孔喙锁韧带重建术的手术技术和初步临床效果。[方法] 2020年4月—2021年9月，对18例肩锁关节脱位（RockwoodⅢ～V）患者采用关节镜监视下喙突免钻孔喙锁韧带重建术进行治疗。首先于锁骨外侧占其全长16%、25%位置处建立锁骨双隧道。利用引线将TightRope钢板的高强线绕过喙突基底部，并从锁骨双隧道穿出。内侧隧道放置纽扣板，外侧隧道放置可调板。然后收紧高强线使袢钢板与锁骨紧密贴合，逐渐复位肩锁关节，最后再次打结固定。[结果]所有患者均顺利完成手术，无严重并发症，随访时间5～22个月。与术前相比，末次随访时肩关节VAS、ASES评分和Constant评分均显著改善（P<0.05）。[结论]关节镜下喙突免钻孔喙锁韧带重建术治疗肩锁关节脱位能够取得良好临床疗效。     

双束纽扣带袢钢板治疗肩锁关节脱位的疗效分析

目的 分析双束纽扣带袢钢板(Tightrope系统)固定肩锁关节及原位重建喙锁韧带治疗肩锁关节脱位的疗效.方法 2017年2月-2020年2月采用双束纽扣带袢钢板做内固定材料治疗16例急性肩锁关节脱位的患者.结果 16例均获得随访,随访时间10～24个月,平均12.5个月.术后肩锁关节复位良好,无关节疼痛,无喙突、锁骨...     

三重带袢纽扣钢板与锁骨钩钢板治疗急性肩锁关节脱位的疗效比较

[目的]比较三重带袢纽扣钢板与AO锁骨钩钢板治疗RockwoodⅢ型肩锁关节脱位的疗效.[方法]2008年10月～2010年3月,分别对32例RockwoodⅢ型肩锁关节脱位的患者采用三重带袢纽扣钢板重建喙锁韧带与AO锁骨钩钢板治疗.对两组患者术后第1年Constant评分进行对比分析.[结果]随访12～26个月,平均随访15个月.术后第1年,三重带袢纽扣钢板组与AO锁骨钩钢板组的Constant评分分别为94.72±5.90,89.84±7.31,差异有统计学意义(P=0.000);两组Constant评分的差异主要是疼痛评分(14,53±1.48、10.94±2.35,P=0.000)和外展活动评分(9.31±0.97、8.81±1.23,P=0.003).[结论]三重带袢纽扣钢板重建喙锁韧带治疗RockwoodⅢ型肩锁关节脱位的疗效优于锁骨钩钢板,主要的优势为肩部疼痛发生率低于锁骨钩钢板,肩关节外展活动度优于锁骨钩钢板.     

喙肩韧带移位联合锁骨钩钢板治疗8例Rockwood Ⅲ型肩锁关节脱位

[目的]探讨喙肩韧带移位联合锁骨钩钢板治疗RockwoodⅢ肩锁关节脱位的临床疗效及并发症。[方法]回顾分析本院2010年8月~2013年7月收治的8例RockwoodⅢ型肩锁关节脱位,行喙肩韧带移位替代喙锁韧带,锁骨钩钢板固定。术后颈腕吊带固定1周,加强肩关节功能训练。[结果]8例患者均获得随访,随访时间24~59个月,平均38.5个月。6例取出钢板,取钢板时间为术后12~36个月,平均18.7个月,其中1例术后18个月钢板断裂,未见感染、畸形、再脱位等并发症。术后1年内,VAS评分随着时间延长而减少,而肩关节功能评分逐渐增加。末次随访时VAS评分(0.38±1.06)分,肩关节功能评分(96.13±4.36)分。6例去除钢板前后肩关节功能评分对比,两组间差异无明显统计学意义(P0.05),但去除钢板后肩关节功能评分仍高于去除前。[结论]喙肩韧带移位联合锁骨钩钢板短期内存在肩关节慢性疼痛及肩关节功能受限,长期随访临床疗效良好。锁骨钩钢板存留体内可能会影响肩关节功能,建议及早取出。     

全关节镜下双纽扣钢板固定技术治疗急性肩锁关节脱位的初步临床疗效观察

目的探讨全关节镜下双Endobutton纽扣钢板固定技术治疗急性肩锁关节脱位重建喙锁韧带的疗效。方法2007年8月至2009年3月间,肩关节镜下使用双Endobutton纽扣钢板固定技术行喙锁韧带重建术治疗RockwoodⅢ型新鲜肩锁关节脱位患者共8例,其中男6例,女2例,年龄22～53岁,有明确外伤病史1～15d,平均4.6d。手术均在肩关节镜下用2个Endobutton纽扣钢板和4股5号爱惜邦缝线行肩锁关节复位后喙锁韧带重建术。术后悬吊制动4～6周再行康复锻炼,术后3个月、半年和1年分别进行随访,并拍摄X线片,用VAS评分和Constant评分进行疗效评价。结果8例患者均取得了3个月以上的随访,平均随访11个月。其中1例术后3个月时仍有肩锁关节疼痛,肩关节活动范围轻度受限,8例患者Constant评分平均为93.9分,VAS评分平均为1.75,术后6个月时均无明显疼痛,对肩关节功能均满意,X光片显示无再发脱位和半脱位。结论肩关节镜下应用双Endobutton纽扣钢板固定技术行喙锁韧带重建术是治疗RockwoodⅢ型新鲜肩锁关节脱位的一种有效方法,此种手术方式有效提供了早期机械稳定性,为韧带的愈合和瘢痕形成提供了条件,术后对锁骨运动中的旋转机制没有影响。手术创伤小,恢复快,并发症少。严格掌握手术适应证,熟练的关节镜下操作技术,对镜下正常解剖结构的认识和骨隧道的正确定位是手术成功的关键。     

带袢钢板重建喙锁韧带与锁骨钩钢板内固定治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位的比较

目的 比较带袢钢板重建喙锁韧带与锁骨钩钢板内固定治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位对患者肩关节活动度、肩关节功能的影响。方法 纳入自2018-01—2021-01诊治的76例Rockwood Ⅲ～Ⅴ型肩锁关节脱位,其中40例采用带袢钢板重建喙锁韧带治疗（带袢钢板组）,36例采用锁骨钩钢板内固定治疗（锁骨钩钢板组）。比较两组术后6个月肩关节功能Constant-Murley评分、末次随访时肩关节活动度、并发症发生情况。结果 76例均获得随访,随访时间平均8.4(6～12)个月。带袢钢板组出现1例（2.5%）并发症（喙锁韧带骨化）,锁骨钩钢板组出现6例（16.7%）并发症（3例喙锁韧带骨化,2例肩峰撞击综合征,1例肩锁关节骨性关节炎）,带袢钢板组并发症发生率低于锁骨钩钢板组,差异有统计学意义（P<0.05）。带袢钢板组术后6个月肩关节功能Constant-Murley评分高于锁骨钩钢板组,末次随访时肩关节外展上举活动度、前屈上举活动度均大于锁骨钩钢板组,差异有统计学意义（P<0.05）。结论 带袢钢板重建喙锁韧带治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位的疗效优于锁骨钩...     

喙锁、肩锁韧带修复联合锁定锁骨钩板内固定治疗肩锁关节脱位的疗效观察

目的观察采用喙锁、肩锁韧带修复联合锁定锁骨钩板内固定治疗RockwoodⅢ~Ⅴ型新鲜肩锁关节脱位的临床疗效。方法回顾性分析自2012-03—2015-03采用喙锁、肩锁韧带修复联合锁定锁骨钩板内固定治疗的19例RockwoodⅢ~Ⅴ型新鲜肩锁关节脱位。采用Herscovici评分标准评定疗效。结果本组19例均获得随访12~16个月,平均12.3个月。切口均一期愈合,术后X线片显示肩锁关节复位良好。所有患者术后4~6周恢复肩关节功能,取出内固定后复查X线片未见再脱位。末次随访时Herscovici评分:优17例,良2例。结论采用喙锁、肩锁韧带修复联合锁定锁骨钩板内固定治疗RockwoodⅢ~Ⅴ型新鲜肩锁关节脱位可获得满意的临床疗效,同时手术操作简单,安全有效。     

三重带袢纽扣钢板与锁骨钩钢板治疗青壮年肩锁关节脱位的对比

目的较三重带袢纽扣钢板和锁骨钩钢板治疗RockwoodⅢ型肩锁关节脱位的临床疗效。方法收集本院2013年6月至2017年6月期间,采用微创小切口三重带袢纽扣钢板内固定治疗RockwoodⅢ型肩锁关节脱位病例(A组)和锁骨钩钢板内固定病例(B组)资料。评价病例手术前后的视觉模拟疼痛评分、Constant-Murley肩关节功能评分、喙锁间距及术后并发症情况。结果 60例病例获得12个月的随访。两组病例术后均获得满意的肩关节功能,X线检查无肩锁关节再脱位发生。A组术后1天、3月、1年的视觉模拟疼痛评分均明显低于B组,而术后3月Constant-Murley肩关节功能评分明显高于B组,差异有统计学意义(P0.05)。结论两种术式治疗肩锁关节脱位均能获得良好的效果,都可以提供初始的机械稳定性;三重带袢纽扣钢板内固定治疗肩锁关节脱位比锁骨钩钢板内固定手术创伤小、并发症少,且无需二次手术取出内固定物,临床更具优势。     

采用纽扣钢板和锁骨钩钢板治疗肩锁关节脱位临床疗效比较研究

目的通过比较分析应用纽扣钢板和锁骨钩钢板两种内固定方法治疗新鲜RockwoodⅢ型及以上肩锁关节脱位的临床效果,探讨纽扣钢板的优势,为纽扣钢板内固定治疗提供重要的临床效果理论依据。方法选取2012年1月到2013年12月,本院收治的60例RockwoodⅢ型及以上肩锁关节脱位患者,随机分为观察组和对照组,分别行纽扣钢板和锁骨钩钢板内固定治疗肩锁关节脱位,术后比较两组患者手术时间、术中出血量、肩关节功能评分及复位丢失量,收集数据并进行比较。结果 60例患者均获随访6-18个月,平均随访12个月,所有患者均得到较好复位,术后无切口感染、锁骨骨折、腋动静脉及臂丛神经损伤等。观察组患者手术时间（50.96±7.42）分钟,术中出血量（61.37±9.28）ml。术前Constant评分（58.34±7.21）,术后6个月（93.58±4.18）,术后12个月（94.27±5.26）。复位丢失测定,术后3天测量的组内喙锁距离为（24.93±2.41）mm,术后6个月测量组内喙锁距离为（25.37±2.62）mm,术后12个月距离（26.17±2.85）mm,平均丢失（1.62±0.83）mm。对照组患者手术之间（69.34±8.25）分钟,术中出血量（90.57±8.91）ml。术前Constant评分（58.34±7.21）,术后6个月（89.47±6.55）,术后12个月为（92.19±5.47）。复位丢失测定,术后3天测量的组内喙锁距离为（27.82±2.57）mm,术后6个月测量喙锁距离为（28.87±2.71）mm,术后12个月（29.17±1.39）mm,平均丢失（1.93±1.37）mm。纽扣钢板较普通锁骨钩钢板内固定治疗RockwoodⅢ型及以上肩锁关节脱位患者手术时间最短,出血量更少。在术后肩关节功能恢复和复位丢失量均较锁骨钩钢板临床疗效好。结论纽扣钢板内固定治疗肩锁关节脱位复位丢失较小,固定安全、可靠,是治疗RockwoodⅢ型及以上肩锁关节脱位较为理想的方法。     

关节镜下袢钢板治疗急性肩锁关节脱位疗效分析

目的回顾性分析关节镜下袢钢板技术及AO锁骨钩钢板技术治疗RockwoodⅢ型及以上急性肩锁关节脱位的临床疗效对比分析。方法收集我科自2012年12月至2016年12月诊治的63例Rockwood分型为Ⅲ～Ⅵ型的急性肩锁关节脱位患者,其中男性37例,女性26例;年龄在18～55岁,平均年龄(42.3±1.1)岁。63例患者均有明确外伤史。将全部患者按随机表法随机分为两组:关节镜手术组33例(实验T组),开放性AO锁骨钩钢板手术组30例(对照A组)。术后所有患者均使用肩颈腕托带悬吊4周,术后第2天开始在医师的指导下进行肩关节非负重功能锻炼,术后4周开始肩关节主动功能锻炼,逐渐过渡到术后3个月基本恢复正常的肩关节活动。术后1周、2周、1个月、3个月、6个月、12个月门诊随访,并行X线检查,通过视觉模拟评分(visual analogue scale,VAS)、Constant-Murley肩关节功能评分、记录术后12个月患肩的喙锁间隙、肩锁间隙和相关并发症情况进行对比疗效评价。结果 63例患者术后均获12个月随访,术后1个月前关节镜手术组VAS评分优于锁骨钩钢板手术组,差异具有统计学意义(P0.05),此后两组间无明显统计学意义(P0.05)。术后2周前关节镜手术组Constant-Murley评分优于锁骨钩钢板手术组,差异具有统计学意义(P0.05),此后两组之间无明显统计学差异(P0.05)。关节镜手术组在术中出血量、手术切口大小及在术后早期改善肩关节疼痛和关节活动范围方面均优于锁骨钩钢板手术组,同时术后并发症较锁骨钩钢板手术组更少。结论关节镜下袢钢板技术治疗Rockwood分型为Ⅲ～VI型的急性肩锁关节脱位,较传统的锁骨钩钢板技术具有微创、固定牢固、康复快、美观、满意度高等优点,同时还可对关节内其他损伤进行即时探查和修复。关节镜下袢钢板技术为肩锁关节有效地提供了早期的机械稳定性,为韧带的愈合提供了稳定的条件。     

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 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.     

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.     

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.     

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.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.