寰椎经后弓侧块螺钉固定通道的CT测量

目的:提供国人寰椎CT测量的数据,探讨寰椎经后弓侧块行螺钉置钉的可行性。方法:采用50具寰椎骨标本,对经寰椎后弓侧块的螺钉固定通道进行多个切面的CT断层扫描并测量。结果:将寰椎后结节中点旁开18～20mm的矢状面与后弓下缘上方2mm处的水平面的交线在后弓后方的投影点确定为进钉点;进钉方向保持与冠状面垂直,在矢状面上钉尖向头侧倾斜约5°,是寰椎经后弓侧块螺钉固定较理想的置钉通道。结论:寰椎具备行经后弓侧块螺钉内固定的条件。     

寰椎测量及其经后弓侧块螺钉固定通道的研究

目的：提供国人寰椎的数据，探讨经寰椎后弓侧块（类似椎弓根）螺钉固定的可行性。方法：用游标卡尺对50例干燥寰椎标本进行测量。在实验研究的基础上，对5例寰枢椎不稳患者采用经寰椎后弓侧块螺钉和枢椎椎弓根螺钉加钢板内固定，术中用卡尺和量角器测量寰椎后弓进钉点及进钉方向，术后在X光片和CT片上测量经寰椎后弓侧块螺钉通道。结果：测量得出寰椎后弓、侧块、椎动脉沟、后弓进钉点、后弓侧块螺钉通道的轴线长度及进钉方向等参数。临床5例10枚经寰椎后弓侧块螺钉均准确置入寰椎内，无穿破骨皮质或损伤神经血管病例。结论：寰椎具备行经后弓侧块螺钉内固定的条件。     

寰椎后弓侧块螺钉进钉角度的影像学研究及临床应用

目的探讨寰椎后弓侧块螺钉置钉安全角度及临床应用价值。方法对30名寰枢椎形态正常者行颈椎侧位X线摄片和寰枢椎轴位CT扫描,在影像学图像上对寰椎后弓最小高度、矢状面最大进钉倾斜角、最大进钉内倾角等参数进行测量。应用影像学观测的进钉角度对21例上颈椎不稳定患者行后路寰椎后弓侧块螺钉固定,术中观察后弓侧块螺钉置入后对周围重要组织结构的影响,术后观察有无神经症状加重。其中13例行手术前后CT检查,并测量螺钉置入前后的相关参数,评估置钉的安全性。结果(1)寰椎后弓侧块矢状面进钉倾斜角最大头倾10°、最大尾倾6°,最大倾斜角随寰椎后弓最小高度的增加有增大的趋势;(2)当进钉点由内侧改为外侧时,置钉内倾角需作0°～30°的相应调整;(3)手术实际进钉角度与术前预测有一定的差异,但均在预测范围内;(4)临床病例均置钉成功,影像学显示在常用的进钉区域内置钉无螺钉伤及椎动脉、脊髓等周围组织的现象。结论寰椎后弓侧块置钉在矢状面和轴平面上均有一定的安全角度范围,依据此范围置钉可增加寰椎后弓侧块螺钉固定的安全性和可操作性。     

多轴向钉棒系统经寰椎侧块枢椎椎弓根 螺钉固定治疗寰枢椎不稳

[目的]探讨应用多轴向钉棒系统经寰椎侧块枢椎椎弓根螺钉固定治疗寰枢椎不稳的方法及疗效.[方法]应用多轴向钉棒系统治疗寰枢椎不稳12例,术前JOA评分平均7.6分;寰椎使用侧块螺钉,进钉点选择在寰椎后结节中点旁18～20 mm与后弓下缘以上2 mm的交点处,钉道方向与冠状面垂直,矢状面上螺钉头端向头侧倾斜约5°;枢椎下关节突根部中点为进钉点,钉道与矢状面夹角约15°,与横断面夹角约25°.[结果]术后无1例发生椎动脉及脊髓损伤,JOA评分平均15.1分,改善率平均为87.3%.[结论]多轴向钉棒系统治疗寰枢椎不稳复位简单,具有稳定的三维固定效果,安全可靠.     

虚拟手术系统支持下寰椎侧块螺钉固定相关数据的测量

[目的]通过结合当前虚拟手术系统辅助手术的优势,测量寰椎侧块螺钉固定通道的相关数据.[方法]选取8例16侧无破损和畸形的寰椎(C1)防腐头颈标本,先行CT扫描,后将数据导入虚拟手术系统进行重建,测量寰椎侧块数据:选择侧块与后弓根部下方交界区和横突孔的内侧缘与寰椎后弓内侧壁中点为进钉点,测最,L1:横突孔的内侧缘与寰椎后弓内侧壁的距离,L2:进钉点与侧块前缘最高点的距离,L3:进钉点与侧块前缘的垂直距离,α:进钉点的垂线与寰椎侧块上缘切线的角度,β:进钉点垂线与横突孔内侧缘切线的角度,γ:进钉点垂线与侧块内侧缘切线的角度,内斜角度δ:(β+γ) /2-β.左右两侧均测量3次,取其均值,进行统计学分析.[结果]虚拟手术系统测量寰椎侧块相关参数L1、L2、L3、α、β、γ、δ,经统计学分析,左右侧测量值均无统计学差异(P＞0.05).[结论]选择侧块与后弓根部下方交界区处寰椎后弓内壁外约5 mm为进钉点,侧块螺钉进钉深度在18～22 mm,上倾斜约18°～20°,在矢状位上可内收6°.     

后路寰椎侧块螺钉结合枢椎椎弓根螺钉固定治疗上颈椎不稳

目的：总结应用寰椎侧块螺钉与枢椎椎弓根螺钉技术固定融合治疗寰枢椎不稳的效果，探讨寰枢椎不稳的治疗方法。方法：采用寰椎侧块螺钉与枢椎椎弓根螺钉技术对15例寰枢椎不稳的患者进行了固定术，同时行自体髂骨融合。分别应用Vertex 7例，Axis 3例，和cervifix 5例，齿状突陈旧性骨折5例，新鲜Ⅱc型齿状突骨折6例，先天性游离齿状突4例。寰椎侧块螺钉进钉点选择在寰椎后结节中点旁开18mm～20mm，与后弓下缘以上2mm的交点，钉道方向在冠状面垂直，矢状面上螺钉头端向头侧倾斜约5°.枢椎进钉点为枢椎下关节突根部中点，钉道与矢状面夹角约15°，横断面夹角约30°。螺钉直径3．5mm，寰椎侧块螺钉长度28mm～32mm，枢椎椎弓根螺钉长度为22mm～26mm。结果：所有患者均未发生脊髓损伤和椎动脉损伤。随访10～25个月，平均14个月。术前JOA评分5．1～10．9分，平均7．6分。术后JOA评分13．2～16．8分，平均14．8分，改善率87．5％。植骨块全部融合，无内固定断裂、松动。结论：后路寰椎侧块螺钉与枢椎椎弓根螺钉技术稳定性良好，具有三维固定的优点，值得推广。     

不同内倾角置入寰椎后路侧块螺钉的安全性比较

目的:将寰椎后路侧块螺钉上倾角固定在15°的情况下,比较不同内倾角度置钉相对应的寰椎侧块有效宽度和进钉深度,以确定寰椎后路侧块螺钉在横断面上的最佳内倾角度。方法:募集颈椎结构正常的健康成年国人64名,男32名,女32名;年龄32.7±7.8岁(18~60岁),进行颈椎CT平扫,通过Mimics软件对志愿者的颈椎CT数据进行测量,在寰椎后路侧块螺钉上倾角为15°的情况下,分别测量内倾角度为0°、5°、10°、15°、20°、25°、30°和理想内倾角(β角)时的寰椎侧块有效宽度和寰椎后路侧块螺钉的进钉深度;测量正中矢状面与寰椎后弓最后缘的交点与进钉点之间的距离和进钉点处的后弓下缘侧块高度;并进行统计学数据分析。结果:寰椎后路侧块螺钉的β角男性为20.01°±2.97°,女性为21.89°±3.14°。寰椎后路侧块螺钉内倾角度为0°、5°、10°、15°、20°、25°、30°和β角时的寰椎侧块有效宽度男性分别为8.95±1.18、9.51±1.14、10.00±1.17、10.42±1.20、10.39±1.29、9.41±1.25、8.04±1.21、11.02±0.96mm,女性分别为7.64±1.01、8.31±1.11、8.88±1.10、9.32±1.11、9.51±1.09、8.90±1.02、7.62±1.07、9.97±0.98mm;进钉深度男性分别为19.03±1.34、19.60±1.39、20.28±1.47、21.20±1.48、22.11±1.54、23.06±1.63、24.19±1.97、22.37±1.52mm,女性分别为17.47±1.68、17.90±1.64、18.50±1.79、19.31±1.93、20.47±2.03、21.67±2.18、22.89±2.38、21.26±1.99mm。相较于其他内倾角,β角对应的寰椎侧块有效宽度最大且差异有统计学意义(P0.01)。寰椎后路侧块螺钉内倾角为β时,寰椎后路侧块螺钉进钉点距离正中矢状面与寰椎后弓最后缘的交点距离男性为28.35±1.75mm,女性为26.70±1.60mm;进钉点处的后弓下缘侧块高度男性为4.38±0.85mm,女性为4.13±0.80mm。结论:寰椎后路侧块螺钉上倾15°时,以所对应的寰椎侧块有效宽度最大的内倾角β角进钉,理论上损伤椎动脉、脊髓等结构的几率最低。     

枕寰枢后路经关节螺钉内固定的可行性研究

目的明确后路寰枕关节经关节螺钉固定的螺钉、进钉点植入角度、钉道角度和螺钉长度。探讨枕颈部经关节螺钉内固定技术的手术指征效果和并发症。方法在 2 0例含有完整寰枕关节的干燥骨性标本上 ,直视下进行后路寰枕关节经关节克氏针植入 ,在头尾侧和侧位X线片上测量理想的钉道角度和钉道长度。 30例正常成年人的寰枕关节进行三维CT重建 ,同时测量后路寰椎关节经关节螺钉钉道角度的可调范围。 12例新鲜枕颈部标本进行后路枕颈部关节螺钉内固定 ,术后行正、侧位X线片和三维CT重建 ,以验证螺钉位置。结果干燥标本模拟X线片测量 ,寰枕关节螺钉的钉道在矢状面上呈上倾 ,在冠状面上呈内倾 ,钉道的理想角度为 :在矢状面上倾角为 5 3.3°± 3.4° ,在冠状面内倾角为 2 0 .0°± 2 .6°。螺钉钉道长度为 (2 9.2 8± 2 .4 6 )mm。依据三维CT重建后测量 ,钉道方向与矢状面上倾角存在一个可调范围 ,一般为 4 9.6°± 2 .0°,与冠状面的内倾角也存在一个可调范围 ,一般为 4 0 .4°± 3.4°。齿突与枕髁前方最高点间距为 9.80～ 17.7mm ,平均 (13.4 3± 1.93)mm。寰枕关节关节螺钉内固定 ,影像学检查显示 ,螺钉钉道均经过寰枕关节 ,未进入神经管。结论寰枕关节后路经关节螺钉植入存在一定的方向性 ,钉道长度和钉道角度     

寰椎侧块螺钉与枢椎弓根螺钉徒手植入技术的研究与应用

[目的]探讨徒手植入寰椎侧块螺钉与枢椎椎弓根螺钉方法,总结临床应用效果。[方法]新鲜成人寰枢椎标本各50具,男女各25具,用尖嘴咬骨钳咬除进钉点骨皮质,先后分别用1.5、2.5 mm克氏针制备钉道,再用锤子将导锥顺着制造的钉道小心击入,待有落空感时停止;寰椎侧块螺钉进钉点选择在寰椎后结节中点旁开18~20mm,与后弓下缘以上2 mm的交点,钉道方向在冠状面垂直,矢状面上螺钉头端向头侧倾斜约5°。枢椎进钉点为枢椎下关节突根部中点,钉道与矢状面夹角约15°,横断面夹角约30°。临床寰枢椎不稳患者26例,男15例,女11例,平均39.5岁;应用钉棒系统17例,钉板系统9例。术前JOA评分5.1~10.6分,平均7.5分。[结果]术后无1例发生脊髓和椎动脉损伤。随访9~32个月,平均15个月,JOA评分12.9~16.5分,平均14.5分,改善率87.6%。植骨块全部融合,无内固定断裂、松动。[结论]寰椎侧块螺钉与枢椎椎弓根螺钉徒手植入技术简单、可靠,值得推广。     

后路寰椎侧块螺钉结合枢椎椎弓根螺钉固定治疗寰枢椎不稳

目的探讨应用寰椎侧块螺钉与枢椎椎弓根螺钉固定融合治疗寰枢椎不稳的疗效。方法2002年2月至2004年3月,采用寰椎侧块螺钉结合枢椎椎弓根螺钉技术治疗寰枢椎不稳15例,男9例,女6例;年龄15～57岁,平均39.5岁;齿突陈旧性骨折5例,先天性游离齿突4例,新鲜齿突骨折6例(AdersonⅡC型)。所有患者均伴有寰枢椎半脱位或不稳,表现为不同程度的颈枕区疼痛,活动受限。术前JOA评分5.1￣10.9分,平均7.6分。术前行颅骨牵引。寰椎侧块螺钉进钉点选择在寰椎后结节中点旁18￣20mm与后弓下缘以上2mm的交点处,钉道与冠状面垂直,矢状面上螺钉头端向头侧倾斜约5°。枢椎椎弓根螺钉进钉点为枢椎下关节突根部中点,钉道与矢状面夹角约15°,与横断面夹角约30°。螺钉直径3.5mm,寰椎侧块螺钉长28～32mm,枢椎椎弓根螺钉长22～26mm。应用Vertex7例,Axis3例,Cervifix5例。结果15例患者共置入寰椎侧块螺钉和枢椎椎弓根螺钉各30枚。术后无一例患者发生脊髓和椎动脉损伤。所有患者均获随访,随访时间10～25个月,平均14个月。术后6个月JOA评分13.2～16.8分,平均14.8分,改善率为87.5%。骨折的齿突均骨性愈合,植骨块全部融合,无内固定断裂、松动。结论后路寰椎侧块螺钉结合枢椎椎弓根螺钉固定具有稳定的三维固定效果,可用于治疗寰枢椎不稳。     

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.     

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.