几丁糖胶原复合膜及激活态雪旺细胞修复周围神经缺损的实验研究

目的研究几丁糖胶原复合膜、激活态雪旺细胞(activatedSchwanncell,ASC)促进周围神经再生的作用。方法将激活态雪旺细胞培养于几丁糖胶原复合膜后,将膜缝制成导管修复大鼠坐骨神经10mm的缺损(D组);并以自体神经移植(A组)、几丁糖胶原复合膜管(B组)及几丁糖胶原复合膜加脑源性神经营养因子[(brainderivedneurotrophicfactor,BDNF)C组]为对照。术后4、8、12周观察肢体运动,复合肌肉动作电位(CMAP)的波幅、潜伏期和运动神经传导速度(MNCV)。术后12周取材,样本染色观察神经轴突再生情况。结果几丁糖胶原复合膜加激活态雪旺细胞修复10mm神经缺损的效果优于几丁糖胶原复合膜加BDNF,与自体神经相似。结论几丁糖胶原复合膜加激活态雪旺细胞能有效地促进周围神经再生。     

同种异体神经复合体修复兔坐骨神经缺损的研究

目的 用种植胎兔雪旺细胞的去细胞同种异体神经复合体修复兔缺损的坐骨神经,观察坐骨神经再生及功能恢复.方法 健康成年新西兰白兔48只,体质量1.5-2.0 kg,随机分成2组.两组动物均切除一段坐骨神经,造成2.0 cm长的缺损.实验组:用种植胎兔雪旺细胞的同种异体神经复合体修复坐骨神经.对照组:仅用去细胞同种异体神经修复.术后4、8、16周进行大体观察、标本光镜和电镜观察且进行量化分析、肌湿重检测.结果 手术区局部均未出现明显的排斥反应,实验组足部溃疡愈合情况优于对照组,实验组再生神经纤维数目、有髓神经纤维轴突直径、髓鞘厚度4、8、16周分别为(906.25±30.68,1726.25±51.89,2825.13±22.79)、(5.35±0.62,5.46±0.38,5.59±0.80),(1.65±0.37,1.75±0.41,1.83±0.49)均优于对照组,差异有统计学意义(P<0.05).小腿三头肌湿重于术后4周两组间差异无统计学意义(P>0.05),实验组术后8、16周分别为(5.62±0.99,7.38±0.26)恢复优于对照组,差异有统计学意义(P<0.05).结论 种植雪旺细胞的去细胞同种异体神经复合体对神经再生及功能恢复有更好的促进作用.     

亲和素-生物素黏附系统修饰纳米纤维构建组织工程神经的实验研究

目的 观察亲和素-生物素黏附系统(avidin-biotin binding system,ABBS)快速黏附雪旺细胞(SCs)对组织工程神经促进神经再生的影响.方法 以坐骨神经缺损10 mm作为实验模型.取40只Wistar大鼠分成A、B、C、D4组,每组10只.A组:自体神经移植修复组;B组:空白对照组,用聚乳酸己内酮共聚物[ Poly(L-lactic acid-co-epsilon-caprolactone),P(LLA-CL)]支架修复神经缺损;C组:P(LLA-CL)支架上用普通方法黏附雪旺细胞修复神经缺损;D组:P(ILA-CL)支架上用ABBS法黏附雪旺细胞修复神经缺损.术后3个月,检测坐骨神经功能指数、神经传导速度、再生神经轴突及髓鞘厚度,评估ABBS对于促进神经再生的影响.结果 C组与D组的神经修复效果无差别.虽然修复效果不及A组,但是均明显好于没有雪旺细胞的B组.结论 ABBS在动物体内实验中未对组织工程神经促进神经再生造成不利影响,是一种可靠的细胞快速黏附方法.     

犬化学去细胞神经同种异体移植的实验研究

目的以化学去细胞同种坐骨神经移植修复犬坐骨神经的长段缺损，观察其功能恢复及神经再生。方法15犬分成去细胞同种神经组(实验组)6犬、自体神经组(对照组Ⅰ)6犬、新鲜同种神经组(对照组Ⅱ)3犬。右侧坐骨神经造成5．0cm长缺损，以上述三种移植物桥接修复。术后6个月行步态分析、神经电生理及神经再生观察。结果实验组和对照组Ⅰ在运动功能恢复，踝关节运动步态，小腿二头肌运动诱发电位、感觉诱发电位，移植段内新生轴突、血管及雪旺细胞，远端胫神经内有髓神经纤维及靶肌肉运动终板等方面非常相似。对照组Ⅱ神经功能始终无恢复，移植段被吸收。结论化学去细胞同种神经移植物修复犬粗大长段神经缺损时不会被宿主排斥和吸收，其近期功能恢复及神经再生与自体神经移植无明显差别。     

碱性成纤维细胞生长因子对组织工程化外周神经的影响

目的　研究碱性成纤维细胞生长因子 (bFGF)和肝素与乳兔许旺细胞、去细胞基膜管、构成的复合型组织工程化外周神经桥接体修复兔正中神经缺损的效果。　方法　新西兰兔 48只 ,建立左侧上臂正中神经 3 0mm缺损模型 ,随机分为 4组 ,分别用去细胞基膜管种植许旺细胞并复合bFGF及肝素 (Hep)的桥接体 (A组 )、去细胞基膜管种植许旺细胞的桥接体 (B组 )、去细胞基膜管复合bFGF及Hep桥接体 (C组 )、自体神经 (D组 )修复神经缺损 ,于术后 1、3个月分别进行大体观察 ,Masson三色染色光镜观察神经再生、神经内胶原纤维形成及血管形成 ,3个月检测各组桥接体运动神经传导速度 ,并行透射电镜检查 ,称量指浅屈肌肌肉湿重 ,观察神经功能恢复。　结果　去细胞基膜管种植许旺细胞并复合bFGF及Hep的桥接体组 (A组 )神经再生及功能指标 (再生有髓神经纤维密度、平均髓鞘厚度、有髓纤维直径、运动神经传导速度、肌肉湿重恢复率 )与自体神经移植 (D组 )比较 ,差异无显著性 (P >0 .0 5 )。　结论　bFGF及肝素与许旺细胞、去细胞神经基膜管构成的复合型组织工程神经桥接体修复神经缺损能提高神经再生质量。     

预变神经段修复神经缺损的实验研究

目的探讨不同预变时间组移植神经对神经再生的影响。方法以ＳＤ大鼠的不同预变时间组的尺神经作为移植神经，修复其正中神经的缺损。实验侧按移植神经预变时间的不同分为０、１、２、３、４、８周共６组，每组６只ＳＤ大鼠。移植后１２周，检测实验侧趾屈肌群的张力、最大收缩力、再生神经的形态及神经轴突的截面积。结果用预变１周的尺神经修复正中神经后，其趾屈肌群的张力及最大收缩力的恢复率达到正常对照组的８１．１％及８５．９％。显微镜下观察，预变１周组和其它各时间组相比，其再生的神经轴突最多，发育最成熟。结论用预变１周的神经段修复神经缺损，其神经再生能力最佳     

纤维蛋白胶载神经生长因子促进周围神经再生的研究

目的　探讨纤维蛋白胶 (FG)作为神经生长因子 (NGF)载体对周围神经再生的促进作用。方法　将Wistar大鼠 96只随机分为 4组 ,即对照组、FG组、NGF组、FG +NGF组 ,每组 2 4只 ,以大鼠左侧坐骨神经为修复神经模型进行实验。术后 2、4、8周进行组织学检查 ,术后 8周进行电生理检查、肌湿重检测、图像分析和透射电镜观察。结果　FG +NGF组的神经传导速度、肌张力、肌湿重、有髓纤维截面积恢复率分别为 ( 84.10± 2 .33) %、( 83 .88± 2 .96 ) %、( 6 2 .5 4± 5 .94) %、( 71.0 1± 3 .6 2 ) % ,吻合口有髓纤维通过率为 ( 6 5 .5 1± 4.5 4) % ,高于对照组、FG组 ( P <0 .0 1) ,高于NGF组 (P <0 .0 5 ) ,FG +NGF组大鼠坐骨神经再生优于单纯NGF组。结论　纤维蛋白胶可作为NGF的载体 ,用纤维蛋白胶载NGF修复周围神经损伤 ,有促进周围神经再生的作用。     

神经端侧吻合术与侧侧吻合术对神经干损伤后功能恢复作用的比较

目的　比较神经端侧吻合与神经侧侧吻合后功能恢复作用的差异。方法　将Wistar大鼠 18只分成A、B两组 ,每组 9只。端侧吻合组 :左侧腓总神经切断并在胫神经干上外膜开窗后 ,与胫神经主干作端侧吻合 ;侧侧吻合组 :左侧腓总神经切断后与胫神经作侧侧吻合。术后 3个月 ,行形态学检查、电生理检查、肌湿重检查及图像分析 ,评价神经再生及肌肉功能恢复的情况。结果　神经端侧吻合组和神经侧侧吻合组神经纤维的数目分别为 73 2 .8± 5 3 .4、712 .5± 5 8.4,其截面积分别为 (712 .5± 5 8.4) μm2 、(182 .3± 3 9.7) μm2 ,神经的传导速度分别为 (2 5 .6± 8.3 )m /s、(18.5± 9.8)m/s ,胫前肌肉的湿重两组分别为 (2 0 5 .6± 2 0 .7)mg、(2 0 1.8± 2 1.3 )mg ,肌纤维的面积分别为 (13 2 0 .6± 10 3 .9) μm2 、(14 0 3 .7± 13 8.4) μm2 ,再生的运动终板面积分别为 (15 3 7.5±5 2 7.8) μm2 、(1774.2± 45 8.7) μm2 ,吸光度值为 0 .42± 0 .15、0 .5 5± 0 .17,所有测量值差异无显著性 (P <0 .0 5 )。结论　神经端侧吻合术与神经侧侧吻合术的功能恢复差异无显著性     

失神经肌肉和雪旺细胞对神经侧支发芽的影响

目的：观察自体失神经肌肉和雪旺细胞对双侧“正常”胫神经侧支发芽再支配腓神经靶器官的影响。方法：48只SD大鼠被随机分成3组，MSW组（肌－雪旺细胞－开窗），MS组（肌0－雪旺细胞），MW组（肌－开窗），术后一周，用S－100蛋白免疫组化染色确定移植的雪旺细胞存活情况，神经再生16周后，用HRP辣根过氧化物酶追踪剂标记再生的腌神经靶器官运动和感觉神经元，OS／2生物定量计算机图像处理系统定量评价再生发芽的有髓鞘神经，结果：MSW组，平均169个运动神经元侧支发芽支配远侧腓神经，而MW组为64个，MS组仅有26个，脊髓背神经节内，平均标记的感觉的神经元数量为：MSW组1283个，MS组947个，MW组348个。结论：移植的失神经肌肉和雪旺细胞能促进正常的感觉和运动神经 支发芽穿过束膜开窗部位。     

静电纺纳米聚乳酸己内酮共聚物导管修复周围神经缺损的实验研究

目的 探讨应用同轴静电纺丝技术制备的聚乳酸己内酮共聚物[Poly(1-lactide-co-epsilon-caprolactone),P(LLA-CL)]导管,移植修复大鼠周围神经缺损的效果.方法 选取健康SD大鼠54只,随机分成3组,每组18只.先造成坐骨神经1.5cm缺损段,然后分别采用P(LLA-CL)导管桥接(A组)、硅胶管桥接(B组)、自体神经逆行原位移植(C组).分别在术后4、8、12周对大鼠进行大体观察、坐骨神经功能指数检查、神经电生理检查、肌肉湿重、再生有髓神经纤维计数、电镜观察,评价各组神经再生.结果 术后4周时A组再生神经已部分生长到导管的中部;8周时再生神经已通过神经导管,但再生的神经纤细;12周时再生神经粘连较轻,直径较粗.A组的坐骨神经功能指数、神经电生理、肌肉湿重和组织学观察等各项指标均略差于C组,但明显优于B组.结论 纳米聚乳酸己内酮神经导管具有促进神经轴突再生的作用,有望成为自体神经移植的替代材料应用于周围神经缺损的修复.     

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.