X线影像导航系统辅助关节镜下前交叉韧带重建术

目的 探讨X线影像导航系统辅助关节镜下前交叉韧带重建手术的可行性和隧道位置的精确性。方法 2005年12月至2006年2月共行X线影像导航系统辅助前交叉韧带重建手术30例（导航手术组）,同期使用传统关节镜手术技术重建前交叉韧带40例（传统手术组）,术前进行股骨、胫骨隧道理想位置的设计。术中C臂透视机获得正侧位影像后传输入计算机系统形成虚拟工作界面。膝关节周围分别固定股骨、胫骨追踪器。手术工具装配追踪器。经过注册及校准后,导航系统通过捕获追踪器发射的信号实时跟踪手术工具的位置方向,并叠加在工作界面上,达到导航的目的。本文对导航手术组进行总结,术后进行胫骨隧道位置测量,并与传统手术组进行比较。结果术后测量,导航手术组胫骨隧道位置平均值45．90％（41．00％～49．80％,标准差2．36％）,传统手术组胫骨隧道位置在41．05％（范围25．00％～54．00％,标准差6．01％）,两组结果差异有统计学意义（P〈0．05）。同时导航组的平均手术时间较传统组延长20min,透视次数为4次。术后短期随访（1-3个月）,两组膝关节稳定性无明显差异。结论 X线影像导航系统辅助关节镜下前交叉韧带重建手术是安全、可行的,通过术前规划,可以使股骨、胫骨隧道位置更精确。     

红外线计算机导航辅助关节镜下前十字韧带重建中骨隧道定位的准确性研究

 目的 探讨红外线计算机导航对辅助关节镜下行前十字韧带(anterior cruciate ligament, ACL)重建中股骨、胫骨隧道定位的准确性及可行性。方法 回顾性分析2012年1月至2013年6月,采用红外线计算机导航辅助关节镜下定位股骨、胫骨隧道行ACL重建术治疗35例ACL损伤患者资料,男26例,女9例;年龄18~53岁,平均26.8岁;合并半月板损伤21例,内侧副韧带损伤3例。所有患者均采用股薄肌、半腱肌编织缝合作为移植物,骨端均采用羟基磷灰石挤压螺钉、门形钉及微孔钢板固定。术后行KT-1000和Lachman试验,并采用Lysholm和Tegner膝关节评分系统评价膝关节功能及运动水平。结果 35例患者均获得随访,随访时间12～17个月,平均16个月。术后股骨、胫骨隧道位点测量结果平均值分别为63.8%±6.6%、45.7%±4.2%。1例患者术后3个月在胫骨固定追踪器针孔处出现轻度异位骨化,关节活动无明显受限。Lachman 试验由术前1 例Ⅱ度、30例Ⅲ度、4例Ⅳ度改善至术后33例Ⅰ度、1例Ⅱ度、1例;KT-1000试验,术前(6.47±0.75) mm,术后(1.01±1.14) mm。术前双膝关节松弛度差异>5 mm 32 例、3～5 mm 3例;术后0～3 mm 31 例、3～5 mm 2 例、<0 mm 2例。Lysholm和Tegner评分分别由术前(52.74±10.91)分和(4.64±1.34)分提高至术后(93.97±4.13)分和(6.56±0.81)分;术前膝关节活动范围由85.6°±11.2°提高至术后118.3°±5.7°;其中33例无屈、伸受限;2例膝关节屈、伸受限< 10°,经直腿抬高训练、本体感受功能训练,术后6个月膝关节活动范围恢复正常。结论 红外线计算机导航系统辅助关节镜下ACL重建术是根据解剖标志点与运动学数据进行导航,通过检测和记录膝关节的运动学数据,选定隧道位点进行手术,该方法定位股骨、胫骨隧道位置精确,术后疗效评价优良。     

计算机导航辅助关节镜下重建前交叉韧带

目的通过与传统关节镜下重建前交叉韧带(ACL)手术进行比较,说明基于X线影像的计算机导航系统辅助关节镜下重建ACL的手术方法隧道定位更精确。方法2005年12月-2006年3月共完成40例计算机导航系统辅助关节镜下ACL重建手术。选择2005年6月-2006年3月40例传统关节镜下ACL重建手术作为对照组,在X线片上分别测量胫骨隧道和股骨隧道的位置,对两组患者测量结果进行统计学分析。结果计算机导航系统辅助关节镜下ACL重建手术组测量股骨隧道位置平均值为62．3％±5．6％(52％-73％),传统手术组测量股骨隧道位置平均值为56．6％±7．3％(46％-77％)。胫骨隧道位置测量,导航辅助手术组平均值为45．4％±3．8％(37％-53％),传统手术组平均值为41．1％±6．0％(25％-54％)。两组患者的股骨隧道和胫骨隧道位置分别做统计学分析,差异均有显著性意义(P< 0．05)。导航辅助手术组数据更接近解剖重建ACL位置。计算机导航系统辅助关节镜下ACL重建的平均手术时间较传统手术延长20 min,透视次数为4次。结论基于X线影像的计算机导航系统辅助关节镜下ACL重建手术是安全、可行的,可以使股骨、胫骨隧道位置更精确。     

前交叉韧带重建术止点定位的临床研究

[目的]通过比较不同临床结果下前交叉韧带重建术骨隧道止点位置的差异，探讨理想骨隧道的影像学位置。[方法]选择55例关节镜下前交叉韧带重建术病例，对过伸位X线侧位片测量并分别计算股骨、胫骨止点及Blumensaat线的胫骨平台投影点相对位置。根据临床结果不同分两组对上述资料分析影像表现差别。[结果]股骨侧止点位置在不同临床结果的两组间有显著性差异，胫骨止点位置和Blumensaat线投影点位置组间无差异性。胫骨止点均位于Blumensaat线投影点之后。[结论]股骨侧止点位置偏前临床效果较差，大致位于Blumensaat线距股骨外侧髁前缘交点的65％-69％之间。胫骨侧止点在伸直位Blumensaat线胫骨投影点之后，大致位于胫骨平台前后直径距前缘38％-41％之间。术前进行患膝关节的过伸位X线片检查，并测量Blumensaat线的胫骨投影位置，有助于为术前胫骨止点定位提供参考。     

关节镜监视下股骨端横杆式固定重建膝前十字韧带

目的介绍在关节镜监视下利用半腱及股薄肌腱重建膝关节前十字韧带的横杆式固定(Transfix)及其应用体会。方法对72例膝关节前十字韧带断裂患者取自体半腱及股薄肌腱作移植物,在关节镜下应用股骨端横杆、胫骨端界面螺钉固定进行前十字韧带重建,观察此固定方法的可靠性及近期术后疗效,以Lysholm评分评价手术前后膝关节功能。同时行半月板修补2例、部分切除31例、大部分切除8例,软骨损伤病灶修整16例,内侧副韧带修补15例,髌腱断裂修补1例。结果65例患者获随访,随访时间8￣36个月,平均20个月。关节活动度正常,8例患者查体有阳性结果,平均Lysholm评分由术前的(56±6.3)分提高到术后的(91±4.8)分,差异有统计学意义(P<0.01)。复查X线片见2例股骨及胫骨隧道均扩大,5例股骨隧道扩大,2例胫骨隧道近端扩大,未见关节间隙变窄。并发症:4例横杆打入不足,钉头外突,需再打入,2例于术后8及9个月出现横杆钉头突出;3例胫骨切口以下局部皮肤感觉麻木,经治疗后症状消失。结论应用腘绳肌腱股骨横杆式、胫骨界面挤压螺钉固定法重建膝关节前十字韧带的近期疗效佳,移植物固定可靠,手术操作简便。     

胫骨髁间前棘骨折的关节镜治疗

目的 介绍一种治疗胫骨髁间前棘骨折的微创手术方法。方法 1999年 7月～ 2000年 12月,共完成 26例手术。关节镜监视下行骨折复位,利用前十字韧带胫骨导向器在骨床或骨块上准确确定钻孔位置,可吸收缝线横穿前十字韧带基底并经骨床或骨块上的钻孔及骨隧道引出关节外打结、固定。结果 共 22例获得随访,随访时间 2～ 17个月,平均 10.5个月;膝关节活动度正常者 17例,受限者 5例,但均超过 90°; X线片示骨折全部愈合,除 1例外均为解剖复位。结论 关节镜手术治疗胫骨髁间前棘骨折可最大程度地减少手术创伤,手术方法简便易行,可作为治疗此类骨折的常规方法。     

经胫骨隧道与前内侧入路建立前交叉韧带股骨隧道的比较研究

目的 比较关节镜下前交叉韧带(ACL)重建术中经胫骨隧道与髌下前内侧入路建立股骨隧道的长度和角度。 方法回顾性分析2000年11月至2009年11月收治的102例ACL重建手术患者资料,其中50例采用经胫骨隧道建立股骨隧道（经胫骨隧道组）：男39例,女11例;年龄15～49岁,平均（27.9±7.6）岁。52例采用经前内侧入路建立股骨隧道（前内侧入路组）：男33例,女19例;年龄15～56岁,平均(30.5±10.7)岁。术中记录股骨隧道长度,术后行膝关节前后位及侧位X线片检查,测量股骨隧道在冠状面与内、外髁连线及矢状面与股骨干轴线的夹角,并进行统计学分析。 结果 经胫骨隧道组股骨隧道的平均长度[（50.9±5.0）mm]长于前内侧入路组[(37.8±4. 7)mm],差异有统计学意义(t=15.083,P=0. 000);经胫骨隧道组冠状面股骨隧道角度(68.6°±7.0°)、矢状面股骨隧道角度(45.1°±8.1°)均大于前内侧入路组(49.8°±7.7°)、33.7°±9.7°),差异均有统计学意义(t=12. 874,P=0. 000;t =5. 877,P=0. 000)。 结论关节镜下ACL重建术中,采用前内侧入路制备的股骨隧道长度短、角度小。     

关节镜下胫骨侧双固定技术重建前交叉韧带

目的探讨关节镜下前交叉韧带重建术中胫骨侧采用PushLock锚钉联合干预螺钉固定的可行性及临床疗效。方法纳入自2017-03—2017-06在关节镜行韧带重建术治疗35例前交叉韧带断裂,股骨侧采用Endobutton带袢钢板皮质外固定,胫骨侧用1枚干预螺钉及1枚PushLock锚钉固定。结果 35例术后均获得随访,随访时间平均18.3(13～24)个月。术后膝关节MRI显示骨道位置及移植物走行良好,无PushLock锚钉拔出及韧带断裂情况发生。术后1年膝关节Lysholm评分、IKDC评分、膝关节活动度、患侧胫骨较健侧前移差值较术前明显改善,差异有统计学意义(P0.05)。结论关节镜下前交叉韧带重建时采用胫骨侧双固定技术是可行的,可充分利用PushLock锚钉的持续加压作用,增加移植肌腱的整体稳定性,同时在一定程度上避免了可吸收挤压螺钉固定的不足,术后短期临床疗效满意。     

双束重建前十字韧带骨道位置的临床研究

目的 研究双束重建前十字韧带患者术后骨道位置与临床效果的关系,初步探讨双束重建前十字韧带的定位评价.方法 随访研究2005年5至12月33例自体胭绳肌腱双束重建前十字韧带的患者,通过X线片测量其骨道位置.术后29例获14～22个月(平均18个月)随访,进行膝关节功能评分、KT-2000及Biodex肌力测试评价.结果 患者术后IKDC、Lysholm和Tegner评分及KT-2000结果均较术前显著改善(P＜0.01).前内束股骨骨道位于Blumensaat线水平的股骨外髁长度的29.68%±5.25%,高度的16.93%±5.73%.后外束股骨骨道位于Blumensaat线水平的股骨外髁长度的30.33%±9.44%,高度的31.24%±6.87%.前内束和后外束胫骨骨道分别位于胫骨平台长度的32.92%±5.37%和46.33%±7.74%.前内束股骨骨道前后位置与KT-2000 30°前后稳定性呈负相关(P＜0.05),即前内骨道越偏后30°稳定性越好.前内束股骨骨道相对外髁高低程度与患肢术后120°角速度下屈肌力矩呈正相关.后外束股骨骨道前后位置与60°角速度下屈肌力矩呈正相关,后外束胫骨骨道前后位置与120°角速度下屈肌力矩呈负相关.骨道位置与各功能评分均未表现出相关性.结论 双束重建前十字韧带可取得很好的临床效果.X线测量可以较客观、准确地反映骨道的定位情况并分析临床效果.     

基于后十字韧带的膝关节多发韧带损伤两种重建技术的对比研究

目的 比较采用关节镜下经胫骨隧道技术和切开胫骨镶嵌骨块技术重建基于后十字韧带的多发韧带损伤患者术后的后向稳定性和临床疗效.方法 自2005年4月至2009年12月,共连续完成基于后十字韧带的多发韧带损伤重建修复手术135例,2年以上随访者88例.后十字韧带采用关节镜下经胫骨隧道技术重建57例(64.8％),切开镶嵌骨块技术重建31例(35.2％),合并损伤予同期重建或修复.随访时间平均(45.9±17.0)个月(24～77个月).采用KT-1000和Telos应力装置测量手术前后膝关节后向稳定性.采用Tegner、Lysholm、AAOS评分评价临床疗效.结果 两组患者的性别、年龄、受伤至手术时间、合并损伤和主观评分比较,差异均无统计学意义.经胫骨隧道组术前KT-1000两侧差值为(13.5±4.8) mm,术后为(2.4±3.4)mm;术前Telos两侧差值为(14.9±7.1) mm,术后为(4.6±4.0) mm.切开胫骨镶嵌骨块组术前KT-1000两侧差值为(13.7±5.2) mm,术后为(2.2±3.6)mm;术前Telos两侧差值为(14.9±5.9) mm,术后为(4.3±3.9) mm.两组患者KT-1000和Telos两侧差值手术前后组内比较差异均有统计学意义,而组间比较差异均无统计学意义.两组患者术后Tegner、Lysholm、AAOS评分的差异均无统计学意义.结论 采用两种技术重建基于后十字韧带的多发韧带损伤,两组患者术后的后向稳定性及功能评分差异均无统计学意义,且均可明显恢复膝关节后向稳定性.     

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.     

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.     

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.     

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.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Intrathecal administration of sameridine to patients subjected to arthroscopic knee joint surgery

Background: Sameridine, a new substance with both local anesthetic and opioid effects, was administered intrathecally for the first time to humans, i. e. in patients subjected to arthroscopic knee joint surgery.
Method: A dose-escalating (10, 15, 20 and 25 mg), open study was performed in 33 patients. Only two patients were included in the 25 mg group.
Results: Sameridine provided good quality of surgical anesthesia in all patients except those receiving 10 mg. The maximum level of sensory block, Th5–Th7, was reached within 30 min with a median duration of 3.6–3.9 h. The motor block was more profound with increasing dose, but never lasted longer than the sensory block. The influence on heart rate and blood pressure was minor and atropine and ephedrine were needed in four patients. No clinically significant ECG-changes were detected and no arrhythmias were recorded. Oxygen saturation and respiratory rate did not decrease in a clinically significant way and were not affected by concomitant morphine given i. v. postoperatively. There were few side-effects, the most frequent being mild pruritus (10/33).
Conclusion: Sameridine provided clinically adequate anesthesia for the patients receiving the doses of 15, 20 and 25 mg. Further studies are needed to evaluate the substance and it is of great interest to clinically investigate the opioid component with respect to postoperative analgesia.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.