腹腔镜与开放性离断式肾盂成形术的疗效比较

目的比较腹腔镜与开放性离断式肾盂成形术治疗肾盂输尿管连接部梗阻（UPJO）的手术疗效。方法采用经腹腔途径腹腔镜下离断式肾盂成形术38例（A组）。男21例，女17例。年龄8～67岁，平均34岁。病变位于左侧23例，右侧15例。重度肾积水21例，中度17例。经腹膜后开放性离断式肾盂成形术40例（B组）。男18例，女22例。年龄9～63岁，平均32岁。左侧26例，右侧14例。重度肾积水22例，中度18例。对2组的手术时间、术中出血量、术后恢复、临床疗效及并发症进行比较研究。结果A组手术均获成功，无中转开放手术者，手术时间（137．1±30．5）min，术中出血量（143．8±45．2）ml，术后止痛药应用时间（O．8±0．2）d，术后住院时间（7．1±1．2）d，恢复工作时间（24．3±5．6）d。术后发生漏尿1例，经B超引导下肾盂穿刺造瘘3d后痊愈。术后随访6～36个月，吻合口无狭窄，肾积水减轻，中度肾积水12例、轻度积水15例、肾积水消失11例。B组手术时间（135．2±34．6）min，术中出血量（245．3±80．9）ml，术后止痛药应用时间（1．5±0．5）d，术后住院时间（10．3±2．6）d，恢复工作时间为（43．2±11．4）d。发生漏尿2例，分别引流5d和8d治愈；切口感染2例，经换药加抗生素治疗2周后好转；1例腹膜后血肿形成者经再次手术清除腹膜后血肿、止血后于术后第21天出院。术后随访6～36个月，1例吻合口狭窄伴重度积水，其余肾积水减轻（中度肾积水9例、轻度积水16例、肾积水消失14例）。2组手术时间比较差异无统计学意义（P＞0．05），术中出血量、术后止痛药应用时间、术后住院时间、恢复工作时间比较差异均有统计学意义（P＜0．01）。结论腹腔镜与开放性离断式肾盂成形术相比，手术时间相当，前者出血少、创伤小、痛苦轻、并发症少、术后恢复快，术后长期疗效相当。     

椎管内麻醉不同穿刺入路对膝关节镜手术的影响

目的：观察直入穿刺法与旁入穿刺法2种不同椎管内麻醉穿刺方法对膝关节镜手术患者的影响。方法：择期行膝关节镜手术120例，ASA Ⅰ～Ⅱ级，按随机数字表法随机分为直入法穿刺组和旁入法穿刺组。均采用一点法即针内针单间隙穿刺技术。观察每组患者的麻醉起效时间、穿刺成功率、神经异感、硬膜外置管困难发生率、硬膜外导管误入血管发生率、术后腰背痛发生情况，麻醉后1、5、10、30min无创血压、心率、脉搏血氧饱和度。结果：直法与旁入法腰麻硬膜外联合穿刺在麻醉起效时间（5．24±0．4）min vs（5．14±0．6）min、硬膜外置管困难发生率1．7％ vs 1．7％、硬膜外导管误入血管发生率3．4％ vs 1．7％、神经异感发生率3．4％ vs 3．4％无显著性差异（P〉0．05）。麻醉后1、5、10、30min SBP、DBP、HR、SpO2,2组间差异无统计学意义（P〉0．05）。旁入法术后腰背痛的发生率75．0％（45／60） vs 23．3％（14／60）及持续时间（2．44±0．8）d vs（2．04±0．7）d明显低于直入法组（x^2=32．042，P=0．000；t=2．195，P=0．004）。结论：2种麻醉穿刺方法均可安全有效地应用于膝关节镜手术；与直入法相比，旁入法腰麻硬膜外联合麻醉术后腰痛发生率低。     

B型超声波引导行经皮肾穿刺造瘘术88例

目的：总结应用B超引导下行经皮肾穿刺造瘘术的经验。方法：分析使用B超线阵扫描探头实时引导，配以穿刺导向器和经改良的套迭式金属扩张管鞘，行经皮肾穿刺造瘘手术88例104侧肾的分析临床资料。结果：肾穿刺成功率100％，满意放置导管造瘘成功率96.2％(100／104)，无严重并发症。结论：实时B超引导下行经皮肾穿刺造瘘术成功率高，创伤小，安全，可靠。合理设置经皮肾穿刺通道和适当的扩张皮肾通道技巧是手术成功的关键技术。     

低蛋白加α酮酸饮食对5/6肾切除大鼠残肾组织炎症因子表达及病理变化的影响

目的观察低蛋白加α酮酸饮食对5/6肾切除大鼠模型的残余肾功能保护作用及对肾组织炎症反应的影响,并探讨其可能的作用机制。方法30只SD雄性大鼠随机分为3组后行5/6肾切除,术后给予不同的饮食：低蛋白加酮酸组（4％酪蛋白＋2％α酮酸）、低蛋白组（6％酪蛋白）和高蛋白组（20％酪蛋白）,同时设10只SD雄性大鼠为假手术对照组（20％酪蛋白）。检测术前及术后第4、8、12周各组尿蛋白、血白蛋白、Ser、BUN等指标。12周后处死大鼠,观察肾组织病理改变;免疫组化方法检测肾组织单核巨噬细胞抗原（ED-1）、单核细胞化学吸引蛋白质1（MCP-1）及RANTES的表达情况。结果（1）术后4周起,3个切除组Scr、BUN及尿蛋白均持续升高,其中以高蛋白组最显著（P＜0．01）,而低蛋白加酮酸组升高最为缓慢;第12周时,低蛋白加酮酸组显著低于其余2组[Scr为（125．44±5．50）比（172．00±9．54）、（135．22±5．78）μmol/L;尿蛋白量（24h）为（28．36±3．69）比（92．32±34．06）、（46．62±6．19）mg,P＜0．01。（2）与高蛋白组和低蛋白组相比,低蛋白加酮酸组肾组织损害明显减轻,肾小球病理积分为0．38±0．13比0．84±0．28、0．49±0．11,P＜0．01。（3）低蛋白加酮酸组肾小管间质内MCP-1、RANTES的表达比高蛋白组及低蛋白组显著减少,同时ED-1的阳性细胞数也明显减少[肾小管间质ED-1阳性细胞为（3．59±0．78）个比（13．33±1．20）、（6．50±0．99）个,P＜0．05。结论低蛋白加酮酸饮食可改善5/6肾切除大鼠的血脂及肾功能,并可能通过抑制肾组织的慢性炎症反应,减轻残肾组织肾小球硬化和肾间质的病变程度,减少尿蛋白的排泄,从而延缓大鼠慢性肾衰的进展。     

中心静脉导管在行经皮肾造瘘术中的应用

目的:评价中心静脉导管行经皮肾造瘘术临床应用效果.方法:120例需行肾造瘘术的患者随机分为二组:导管组65例,应用中心静脉导管行经皮肾造瘘术;传统组55例,采用传统经皮肾逐步扩张造瘘术.对两组的穿刺次数、手术时间、出血量、手术费用及术后的并发症进行比较.结果:导管组在平均手术时间、术中平均出血量、一次穿刺成功例数、发生并发症例数及平均费用均明显低于传统组,两组比较有统计学意义;两组在平均穿刺次数上无显著性差异,但导管组一次穿刺置人造瘘管的成功率明显高于传统组.结论:应用中心静脉导管行经皮肾造瘘术较传统方法有出血少、一次穿刺成功率高、术后并发症少、操作简便等优点,且经济、安全、有效,值得临床推广应用.     

腹腔镜直肠全系膜切除术治疗中、低位直肠癌的临床安全性对比研究

目的：探讨腹腔镜直肠全系膜切除治疗中、低位直肠癌手术的安全性。方法：回顾性对比分析我院2002年12月～2005年12月开腹直肠癌全系膜切除的病例（开腹组52例），以及2003年1月～2006年6月腹腔镜直肠癌全系膜切除的病例（腹腔镜组49例）。结果：腹腔镜组与开腹组一般资料差异无显著性。与开腹组比较，腹腔镜组术中出血量少[直肠癌前切除术（160±106）ml（n=37）vs（298±186）ml（n=36），t=-3．908，P=0．000；腹会阴联合直肠癌根治术（180±153）ml（n=10）vs（356±170）ml（n=14），t=-2．604，P=0．016]。腹腔镜组肠道功能恢复时间早于开腹手术组[（2．4±1．8）dVS（3．6±1．5）d，t=-3．648，P=0．000]。腹腔镜组总并发症的发生率低于开腹组[14．3％（7／49）g844．2％（23／52），x^2=10．834，P=0．001]。两组清扫淋巴结的数目无差异（12．7±6．5VS13．6±7．0，t=-0．668，P=0．505），下切缘均为阴性。腹腔镜组45例（91．8％）随访2～42个月，开腹组47例（90．4％）随访6～42个月，局部复发率分别4．4％（2／45）、4．3％（2／47）。结论：腹腔镜直肠全系膜切除治疗中、低位直肠癌安全、可行。     

腹腔镜下肾切除术转手助腹腔镜与转开放手术的疗效比较

目的对困难腹腔镜下肾切除手术进行探索，并观察转手助腹腔镜与转开放手术的术中与术后临床指标，为临床应用提供参考。方法1999年12月至2006年11月行各类腹腔镜下肾切除手术273例，23例因出血、粘连、肿瘤侵犯周围脏器等原因改变手术方式。其中转手助腹腔镜手术组12例，男8例，女4例，年龄19-73岁，平均52岁，左侧7例，右侧5例；转开放手术组11例，男6例，女5例，年龄32-68岁，平均48岁，左侧5例，右侧6例。观察2组改变手术方式后的手术时间、出血量、切口长度、术后起床活动时间、肛门排气时间、住院时间等指标。结果转开放组1例死亡，其余病例均顺利完成。转手助腹腔镜组改变手术方式后手术时间为（40．1±12．5）min，术中出血量（377±311）ml，切口长度（6．2±2．7）cm，肛门排气时间（2．2±0．6）d，下床活动时间（2．2±1．1）d，术后住院时间（5．4±1．6）d；转开放手术组改变手术方式后手术时间（80．2±37．6）min，术中出血量（854士306）ml，切口长度（19．8士2．5）cm，肛门排气时间（2．5±0．5）d，下床活动时间（4．2±0．8）d，术后住院时间（10．2±2．9）d。与转开放组相比，转手助腹腔镜组在改变手术方式后手术时间、出血量、切口长度、下床活动时间、术后住院时间方面均有明显优势（P〈0.01）。结论腹腔镜下肾切除手术遇到困难时，转手助腹腔镜手术可作为一项安全合理的选择，较转开放手术出血少、创伤小，恢复快。     

经皮肾镜与微创经皮肾取石术治疗肾结石的效果比较

目的比较经皮肾镜（PCNI，）与微创经皮肾取石术（MPCNL）治疗肾结石的有效性和安全性。方法2004年10月至2006年4月，分别采用PCNL气压弹道超声碎石术和MPCNL输尿管镜下气压弹道碎石术治疗肾结石患者58例和77例。PCNL组患者年龄23～65岁，平均42岁。结石直径1．5～6．0cm，平均3．5cm。MPCNL组患者年龄20～72岁，平均39岁。结石直径1．2～5．6cm，平均3．2cm。对2组患者手术时间、手术并发症和一期结石清除率等指标进行比较分析。结果2组患者分别成功建立22F和16F肾穿刺通道并一期行碎石术。2组鹿角形结石分别为24例和22例，手术时间分别为（92±16）min和（115±15）min，P〈0．05；结石清除率分别为50％（12／24）和59％（13／22），P〉0．05。2组单纯肾盂结石各21例，手术时间分别为（65±11）min和（80±14）min，P〈0．05；结石清除率分别为91％（19／21）和62％（13／21），P〈0．05。2组肾盏多发结石分别为13例和34例，手术时间分别为（95士17）min和（110±12）min，P〈0．05；结石清除率分别为67％（8／12）和88％（30／34），P〈0．05。2组术中或术后出血明显需要输血治疗者分别为5例和4例，术后发热分别为5例和9例，P值均〉0．05。结论PCNL治疗肾结石手术时间短，适合处理较大的肾盂结石；MPCNL适用于治疗较小的肾盂结石及肾盏结石；二者联合应用治疗可提高鹿角形结石的结石清除率。     

腹腔镜手术治疗老年良性妇科疾病的价值

目的探讨腹腔镜手术在老年妇科良性疾病中的应用价值及安全性。方法比较2001年1月～2006年12月27例腹腔镜手术（腹腔镜组）与25例开腹手术（开腹组）的临床资料。结果腹腔镜组手术时间（20．0±7．9）min明显短于开腹组（44．0±7．2）min（t=-11．419，P：0．000）；腹腔镜组术中出血量（21．9±20．0）m1明显少于开腹组（62．6ml±29．4）（t=-5．875，P：0．000）；腹腔镜组术后病率3例明显少于开腹组12例（，：8．606，P：0．001）；腹腔镜组术后排气时间（13．9±2．9）h明显短于开腹组（23．4±4．3）h（t=-9．404，P=0．000）；腹腔镜组住院时间（7．6±0．9）d明显少于开腹组（10．2±1．2）d（t=-8．882，P=0．000）。结论重视老年患者术前合并症的治疗，术中术后加强监护，腹腔镜是老年妇科疾病手术治疗理想的术式。     

袖套法建立大鼠肺移植模型的改进

目的探讨袖套技术建立大鼠肺移植模型的方法改进。方法用改进的袖套技术建立大鼠肺移植模型。结果30例大鼠肺移植，手术成功率90％（27／30），术后生存率100％，供肺摘取需时（1．0±0．5）min，供肺完成肺动静脉和支气管套管时间分别为（1．0±0．5）、（2．0±1．0）和（2．0±0．5）min，供受体肺动静脉和支气管吻合时间分别为（3．0±2．0）、（7．0±2．0）和（1．5±0．5）min。结论改进的袖套技术具有供肺获取、肺动静脉和支气管套管和吻合更快速、简化、有效的优点。     

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.     

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.     

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.