电视胸腔镜辅助下小切口前路手术治疗胸椎疾病

目的评价电视胸腔镜辅助下小切口胸椎前路手术的创伤、安全性、临床疗效和应用价值。方法回顾性分析2005年2月~2007年4月我院施行电视胸腔镜辅助下小切口胸椎前路手术17例。对照组在均衡年龄、性别和疾病构成的条件下,选择开胸脊柱前路手术22例。对两组的围手术期参数、并发症和临床疗效进行比较研究。结果①围手术期参数:小切口组在切口长度、术中出血量、胸痛持续时间、胸腔引流量和住院时间与开胸组有显著性差异(P<0.05);两组手术时间和胸腔引流时间无显著性差异(P>0.05)。②术后并发症:小切口组2例(11.8%);开胸组3例(13.6%),无显著性差异(P>0.05)。③临床疗效:小切口组平均随访15.8个月,开胸组平均随访17.6个月。胸背痛缓解率两组均为100%。两组神经功能恢复比较无显著性差异(P>0.05)。小切口组术后影像学显示病灶清除彻底,脊髓减压充分,内固定效果确切。随访期间未见上下椎体肿瘤及结核的复发或神经功能障碍的加重,未见内固定物松动或断裂。结论电视胸腔镜辅助下小切口胸椎前路手术,与传统开胸手术相比,具有对组织创伤小、术中出血少、恢复快等优势,能安全、有效地应用于胸椎疾病的前路手术治疗。     

应用胸腔镜和传统开胸技术进行前路脊柱侧弯矫形临床比较学研究

目的通过前瞻性研究评价应用胸腔镜和传统开胸手术两种方法进行脊柱侧弯前路矫形的临床效果. 方法将研究对象随机分为胸腔镜组和开胸组,各6例. 结果胸腔镜组出血量 (260±40.0)ml少于开胸组(390±57.3)ml,(t=-4.557,P=0.001).术后上肢功能评分:胸腔镜组(术后1.3±0.3,3个月1.1±0.1)优于开胸组(术后2.1±0.2,3个月 1.5±0.3)(t=-5.435,-3.098;P=0.000,0.001).术后脊柱侧弯平均矫正率: 胸腔镜组平均矫正率59%,开胸组平均矫正率62%,P=0.628.所有病例术后随访平均12个月,均获得良好骨融合. 结论胸腔镜和传统开胸技术进行前路脊柱侧弯矫形均可以获得良好的手术效果.围手术期及术后3个月以内的临床评估,胸腔镜技术在减少术中出血量、胸痛和上肢功能障碍等方面有优势.     

特发性胸椎侧凸胸腔镜下前路矫形与开放小切口前路矫形的疗效比较

目的对特发性胸椎侧凸胸腔镜下前路矫形与开放小切口前路矫形的近期疗效进行比较。方法将23例特发性胸椎右侧凸患者分为两组,A组行胸腔镜下胸椎侧凸前路Eclipse矫形术,共8例,均为女性,平均年龄148岁,平均Cobb角54°,Risser征 ～ 。B组行开放小切口前路CDHTSRH矫形手术,共15例,男2例,女13例,平均年龄138岁,Cobb角平均57°,Risser征 ～ 。对两组病例的手术时间、术中出血量、固定节段、术后引流量、矫正效果以及早期矫正丢失等进行分析。结果两组患者在年龄、Cobb角、侧凸柔软性和固定节段等方面均具有可比性。A组平均手术时间(360±72)min,术中平均出血量(629±145)ml,术后平均引流量(500±150)ml,平均固定节段(74±11)个,平均Cobb角矫正率(74±14)%,经6～18个月随访,近期矫正丢失率(86±27)%。B组平均手术时间(246±64)min,术中平均出血量(300±110)ml,术后平均引流量(210±90)ml,平均固定节段(78±09)个,平均Cobb角矫正率(70±12)%,近期矫正丢失率(46±19)%。A组与B组相比,侧凸矫正率相似(P>005),但手术时间、术中出血量、术后引流量,以及早期矫正丢失率等存在显著差异(P<005)。结论胸腔镜下胸椎侧凸前路矫形手术和开放小切口前路矫形手术具有各自的适应证和优缺点。对于青少年特发性胸椎侧凸     

电视胸腔镜与传统开胸手术治疗外伤性血气胸的效果比较

目的 比较电视胸腔镜(VATS)和传统开胸手术治疗外伤性血气胸的临床效果.方法 血气胸患者41例随机分为实验组和对照组,对照组26例,采用传统开胸手术方法;实验组15例,采用VATS治疗,对两组患者一般临床资料、术中出血量、手术时间、术后胸管放置时间、术后引流量等进行比较.结果 41例患者均无手术死亡、二次开胸止血,术后均未呼吸机辅助呼吸.实验组术中出血量[(176.5 ±78.5) ml]明显少于对照组[(401.3±90.7)ml],手术时间[实验组(64.7-±21.3) min,对照组(129.4±30.3) min]、术后胸管放置时间[实验组(2.3±0.9)d,对照组(4.5±1.0)d]、住院时间[实验组(9.1±2.1)d,对照组(12.7±2.2)d]及术后并发症发生率等方面均少于对照组,两组比较差异有统计学意义(P＜0.05).结论 VATS治疗外伤性血气胸与传统开胸手术比较,诊断快速准确,安全可靠,并发症少.     

全胸腔镜肺叶切除术治疗支气管扩张症的临床研究

目的 比较全胸腔镜肺叶切除术与常规开胸肺叶切除术治疗支气管扩张症的临床效果,探讨全胸腔镜肺叶切除术治疗支气管扩张症的特殊性、可行性和安全性. 方法 回顾性分析2009年5月至2012年1月北京朝阳医院115例支气管扩张症患者的临床资料,根据手术方式不同将115例患者分为两组,常规开胸手术组(开胸组):62例,男28例,女34例;年龄(46.2±11.9)岁;行常规开胸肺叶切除术.全胸腔镜手术组(全腔镜组):53例,男 19例,女34例;年龄(45.7±12.2)岁;行全胸腔镜肺叶切除术.比较两组患者的手术时间、术中出血量、术后胸腔引流量、并发症、住院时间和住院总费用. 结果 围术期无死亡.两组患者手术时间差异无统计学意义;开胸组术中出血量大于全腔镜组[(228.8±121.7) ml vs.( 157.1±123.8)ml,t=2.592,P=0.011].全腔镜组患者术后胸腔引流量[(866.7±439.5) ml vs.(1 805.3±466.7)ml,t=9.003,P=0.000]、拔管时间[(6 6±3.3)d vs.(9.8±4.6)d,t=3.339,P=0.001]、术后住院时间[(7.5±2.2)d vs(11.2±5.4)d,t=3.424,P=0.001]均少于开胸组,但全腔镜组住院费用明显高于开胸组[(38 543.6±11 051.8)元vs.(30 523.4±10 028.5)元,t=3.423,P=0 001],两组患者术后并发症发生差异无统计学意义(P＞0.05).全腔镜组随访45例,随访时间2～14个月,42例咳痰或咯血症状完全消失,3例仍有间断少量咳痰. 结论 全胸腔镜肺叶切除术治疗支气管扩张症是安全、可行的,与常规开胸手术相比较并不增加手术风险,并可显著减轻手术损伤,缩短住院时间.在全胸腔镜手术过程中,对肺部分切除的患者术中应谨慎处理肺残端,而非单一的手术顺序是一种值得推荐的方法.     

胸腔镜肺叶切除术治疗早期肺癌的学习曲线

目的 通过评估胸腔镜肺叶切除术治疗早期肺癌不同阶段的手术效果,探讨胸腔镜肺叶切除术的学习曲线.方法 回顾性分析2006年9月至2008年6月由同一手术组连续完成的60例全胸腔镜下肺叶切除加纵隔淋巴结清扫术治疗早期肺癌的病例资料.按手术先后依次分为4组(A、B、C、D),每组15例,比较各组手术时间、术中出血量、纵隔淋巴结清扫站数及个数、中转开胸率、术后并发症、术后胸管引流时间以及术后住院天数,分析不同阶段的手术效果.结果 各组病例在年龄、性别、肿瘤大小、病理分期以及手术方式等方面差异无统计学意义(P>0.05).A组手术时间(228.0±55.6)min明显长于C组(155.0±33.6)min或D组(152.7±27.4)min(P<0.001),B组手术时间(200.3±67.1)min亦明显长于C组或D组(P<0.05),而C、D两组之间差异无统计学意义(P=0.896);在术中出血量方面,A组(283.3±111.2)ml明显多于C组(156.7±86.3)ml或D组(143.3±67.8)ml(P<0.01),B组(286.7±188.4)ml亦明显多于C组或D组(P<0.01),C、D两组之间差异无统计学意义(P=0.767);各组淋巴结清扫数量、中转开胸率、术后并发症、术后胸管引流时间以及术后住院天数比较,差异均无统计学意义(P>0.05).结论 胸腔镜肺叶切除术的学习曲线大约为30例.     

全胸腔镜与开胸手术治疗肺隔离症的疗效对比

目的探讨全胸腔镜与开胸手术治疗肺隔离症(pulmonary sequestration,PS)的疗效。方法回顾性分析我院2003年1月~2016年3月手术治疗的48例肺隔离症资料,根据患者经济条件,行全胸腔镜手术18例,开胸手术30例。行肺叶切除或隔离肺切除术。比较2组的术中出血量、术后当日胸腔引流量、术后镇痛时间、胸腔引流时间及术后住院时间。结果与开胸组比较,全胸腔镜组术中出血少[(56.1±50.4)ml vs.(120.0±54.2)ml,t=-3.813,P=0.000],术后当日胸腔引流量少[(160.0±56.0)ml vs.(280.0±65.0)ml,t=-6.100,P=0.000],术后镇痛时间短[(2.4±1.2)d vs.(7.6±1.9)d,t=-9.650,P=0.000],胸腔引流时间短[(2.8±1.0)d vs.(5.7±1.5)d,t=-6.755,P=0.000],术后住院时间短[(6.5±2.6)d vs.(10.1±2.8)d,t=-4.160,P=0.000]。2组手术时间差异无统计学意义(P0.05)。术后发生肺部感染、心律失常、肺不张全胸腔镜组分别为1、0、1例,开胸组为3、2、1例,2组差异无统计学意义(P0.05)。结论全胸腔镜手术治疗肺隔离症较传统开胸手术创伤小,术中出血少,疼痛轻,恢复快,住院时间短,是一种可靠安全的手术方式。     

全胸腔镜与小切口开胸手术治疗75岁以上肺癌的比较

目的探讨全胸腔镜手术治疗高龄肺癌的安全性和临床价值。方法回顾性分析2012年1月～2017年12月53例75岁以上原发性肺癌并接受根治性手术的临床资料。全胸腔镜组24例,小切口开胸组29例。比较2组手术时间、术中出血量、淋巴结清扫数量、术后病理分期、术后引流量、术后第2天疼痛视觉模拟评分(Visual Analogue Scale,VAS)、术后住院时间、并发症。结果与小切口开胸手术组比较,全胸腔镜组术中出血量少[(104. 8±66. 2) ml vs.(174. 2±133. 5)ml,t=-2. 320,P=0. 027],术后引流量少[(675. 9±294. 8) ml vs.(897. 1±368. 7) ml,t=-2. 428,P=0. 019],术后疼痛轻[(4. 6±1. 2)分vs.(7. 2±1. 1)分,t=-7. 981,P=0. 000],术后住院时间短[(5. 2±1. 7) d vs.(7. 2±2. 5) d,t=-3. 438,P=0. 001]。2组手术时间、清扫淋巴结数、术后病理学分期差异无显著性(P 0. 05)。术后并发症率分别为17. 2%(5/29)和29. 2%(7/24),差异无显著性(χ~2=1. 066,P=0. 302)。结论相比小切口开胸手术,全胸腔镜手术治疗高龄原发性肺癌同样安全、可行,且恢复快,创伤小。     

电视胸腔镜肺切除治疗肺结核的回顾性队列研究

目的了解胸腔镜下肺切除在肺结核的外科手术治疗中的可行性。方法回顾性分析2013~2017年于西安市胸科医院行肺切除手术164例肺结核患者的临床资料。根据手术方式将患者分为两组:电视胸腔镜手术组(VATS组,85例,男56例、女29例)和开胸组(79例,男52例、女27例)。比较两组临床效果。结果 VATS组手术时间[(151.59±76.75)min vs.(233.48±93.89)min,P0.001],术中出血量[200.00(10.00,1 600.00)ml vs.600.00(150.00,3 400.00)ml,P0.01],术后引流量[575.00(20.00,2 175.00)ml vs. 1 110.00(350.00,3 250.00)ml,P=0.001],拔管时间[4.00(1.00,16.00)d vs. 6.00(2.00,26.00)d,P0.001],术后住院时间方面[13.00(5.00,27.00)d vs. 17.00(9.00,182.00)d,P0.001],要明显短于或少于开胸组;在术后并发症方面,两组差异无统计学意义(10例vs. 17例,P=0.092)。行肺叶切除共97例,其中VATS手术36例,开胸手术61例,两组在手术时间[(211.39±70.88)min vs.(258.20±87.16)min,P=0.008],术中出血量[400.00(100.00,1 600.00)ml vs. 700.00(200.00,3 400.00)ml,P0.010],术后引流量[800.00(125.00,2 175.00)ml vs. 1 250.00(410.00,3 250.00)ml,P=0.001],拔管时间[5.00(2.00,16.00)d vs. 8.00(2.00,26.00)d,P=0.002],术后住院时间[(13.11±4.45)d vs.(19.46±7.74)d,P0.010]等方面,VATS组明显优于开胸组。在术后并发症方面,两组差异无统计学意义(4例vs. 14例,P=0.147)。结论胸腔镜下肺切除治疗肺结核相比常规开胸优势明显,可以作为首选术式。     

完全胸腔镜技术在部分型房室间隔缺损心内矫治术中的应用及优势

目的回顾分析全胸腔镜与正中开胸行部分型房室间隔缺损(partial atrioventricular septal defect,PAVSD)矫治术的临床病例资料,探讨全胸腔镜下在PAVSD心内矫治术中的应用及优势。 方法回顾研究2010年1月至2017年12月于空军军医大学第一附属医院实施PAVSD的226例患者的临床资料,分为完全胸腔镜组及正中开胸组。分析两组患者的手术创伤指标、术后恢复相关临床指标及其远期随访情况进行比较。 结果226例患者均成功接受手术,完全胸腔镜组在输血量[(90.6±52.3)ml比(285±103.5)ml]、术中出血量[(109.2±25.4)ml比(235.3±101.3)ml]、引流量[(115.1±63.2)ml比(225.2±97.3)ml]上均少于正中开胸组,差异有统计学意义(P<0.05);在关胸时间[(12.0±3.6)min比(44.2±15.0)min]、手术时间[(155.3±28.7)min比(183.6±37.6)min]、疼痛评分[(3.4±0.7)分比(6.9±1.5)分]、术后住院时间[(6.2±2.1)d比(10.7±2.9)d]及ICU监护时间[(42.1±11.9)h比(60.3±12.4)h]方面,较正中开胸组缩短,差异有统计学意义(P<0.05);两组主动脉阻断时间差异无统计学意义;完全胸腔镜组术后出现切口愈合不良并发症的概率(0.9%比5.6%)明显低于正中开胸组(P<0.05);完全胸腔镜组术后出现肺不张、气胸的概率略高于正中开胸组,出现脑、肝、肾并发症概率与正中开胸组相仿,差异无统计学意义;完全胸腔镜组术后出现心包压塞、高度房室传导阻滞概率低于正中开胸组,差异无统计学意义;两组患者术后1年心脏左心室射血分数值差异无统计学意义。 结论完全胸腔镜手术行PAVSD心内矫治术手术疗效确实可靠,手术创伤小,术后并发症少,切口隐蔽美观,术后恢复快,是一种安全、有效、微创的手术方式,值得大范围的推广。     

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.