白藜芦醇对人精子冷冻损伤的保护作用

目的:通过在人精子冷冻保护液中添加白藜芦醇,研究其对冻融后精子质量和功能的影响。方法:选择正常精液与少弱精子症样本各50例,液化后的精液样本分别与甘油-卵黄-柠檬酸盐(GEYC)冷冻保护液或含有30μmol/L白藜芦醇的GEYC冷冻保护液混匀。冷冻复苏前后,进行精子活力、存活率及顶体反应分析。采用丙二醛(MDA)及活性氧(ROS)检测试剂盒评估精子脂质过氧化程度及ROS水平。通过罗丹明123(Rh123)染色法及TUNEL试验检测精子线粒体膜电位及DNA损伤。结果:在正常精液和少弱精子症样本组中,与各组冷冻前新鲜精液相比,冻融后前向运动精子百分率、总活力、存活率、线粒体膜电位及顶体反应率均显著下降(P0.05),而精子ROS、MDA水平和DNA碎片指数(DFI)均显著升高(P0.05)。冷冻保护液中添加30μmol/L白藜芦醇后,正常精液组前向运动精子百分率[(43.1±6.3)%]、总活力[(56.9±7.4)%]、存活率[(67.5±5.6)%]、线粒体膜电位[(63.4±7.5)%]及顶体反应百分率[(26.3±4.7)%]较冷冻对照(未加白藜芦醇)的前向运动精子百分率[(32.7±4.8)%]、总活力[(44.8±6.9)%]、存活率[(52.3±6.1)%]、线粒体膜电位[(56.5±7.0)%]及顶体反应百分率[(16.6±3.8)%]均显著提高(P0.05),而精子ROS、MDA水平和DFI较冷冻对照均显著降低(P0.05)。在少弱精子症组中,添加白藜芦醇也均显著地提高了冷冻后精子前向运动百分率、总活力百分率、存活率、线粒体膜电位及顶体反应百分率,尤其是DFI[28.5±4.8)%]较冷冻对照[(36.3±5.7)%]显著降低(P0.01)。结论:在精液冷冻保护液中添加白藜芦醇可以通过降低精子内ROS水平减少精子冷冻损伤,从而改善解冻后精子质量和功能。     

维生素E对人精子冻融氧化应激损伤的保护作用

目的:探讨水溶性维生素E(Trolox)对冻融人精子氧化应激损伤的可能保护作用及机制。方法:选取16份健康生育男性的精液标本,分析精液常规参数及动力学参数后,将每份精液一式4份,1∶1加入冷冻保护液后混匀,不含水溶性维生素E者设为阴性对照组(G0),而G1、G2、G3实验组混合液中分别含有50、100、200μmol/L浓度的水溶性维生素E,冷冻复苏精液常规分析,检测复苏后精液中活性氧(ROS)水平,采用硫巴比妥酸法(TBA)检测精子中脂质过氧化产物丙二醛(MDA)浓度。结果:冻融后各组精子运动参数较新鲜精液参数均明显下降(P0.01),G2组前向运动精子百分率[(53.33±5.63)%]较对照组[(47.85±5.09)%]明显改善(P0.05),精子VCL和VAP高于阴性对照组(P0.05)。G2组与G3组的ROS及MDA均低于阴性对照组(P0.05)。结论:在精液冷冻保护液中添加一定浓度的水溶性维生素E可以减少精子冻融过程中产生的过量ROS,减轻ROS对精子质膜的氧化应激性损伤,从而提高冻融后的精子活力。     

RHO/ROCK信号通路在精子抗冷冻损伤中的作用

目的:探讨RHO/ROCK信号通路在人精子抗冷冻损伤中的作用,为高效精液冷冻保护剂的研制提供理论依据。方法:选取健康精液25份,每份精液分为新鲜组、对照组与RHO通路抑制剂组(抑制剂组)。检测冷冻前后各组精液精子活力、精子存活率、精子膜完整率、正常形态精子百分率、精子DNA碎片指数(DFI)、精子顶体酶活性及精子线粒体膜电位变化;免疫荧光染色检测RHOa/ROCK蛋白在精子中的表达。结果:抑制剂组精液冷冻复苏后精子活力[(57.50±6.83)%vs(51.20±7.70)%,P=0.002]、精子存活率[(60.24±5.53)%vs(52.87±5.07)%,P=0.001]、精子膜完整率[(67.10±4.43)%vs(59.78±5.56)%,P=0.001]、正常形态精子百分率[(7.46±1.28)%vs(4.83±1.11)%,P=0.001]、精子DFI[(18.87±4.07)%vs(27.64±6.64)%,P=0.001]、精子线粒体膜电位(63.11±2.97 vs 56.30±4.28,P=0.001)指标均明显优于对照组;抑制剂组冷冻后精子顶体酶活性与对照组差异无统计学意义(98.30±11.33 vs 97.65±9.31,P0.05)。免疫荧光染色显示RHOa/ROCK蛋白在精子头、颈部广泛表达。结论:RHO/ROCK信号通路在精子冷冻损伤中具有一定作用,抑制其通路活性可明显提高精子抗冷冻损伤的能力。     

线粒体靶向抗氧化剂Mitoquinone对人精子冻融氧化应激损伤的保护作用

目的:探讨线粒体靶向抗氧化剂Mitoquinone(Mito Q)对冻融人精子的保护作用。方法:选取60份健康生育男性精液标本,每份精液一式6份,不含Mito Q者设为对照组(G0),而G1、G2、G3、G4、G5实验组混合液中分别含有2 nmol/L、20 nmol/L、200 nmol/L、2μmol/L、20μmol/L Mito Q,37℃孵育1 h后检测活性氧(ROS)、丙二醛(MDA)和线粒体膜电位(MMP)变化。选取合适Mito Q浓度B1、B2组用于精子冷冻保存,B0组未添加Mito Q,B1、B2组在精子冷冻保护液中分别含有200 nmol/L和2μmol/L Mito Q,进行冷冻保存,检测冷冻复苏后的ROS水平、MDA含量和MMP改变。结果:新鲜精液添加Mito Q孵育后,G3组和G4组前向运动精子百分率[(30.8±10.2)%和(32.7±13.5)%]和总活动率[(70.6±9.0)%和(70.3±11.9)%]显著高于G0组[(17.6±5.0)%、(54.9±11.5)%](P0.05);随着Mito Q浓度的增加,ROS水平呈下降趋势,G3、G4、G5组(分别为86.5±31.6、93.6±42.0、45.1±15.0)显著低于G0组(160.8±39.7)(P0.05);MDA含量G3、G4组[分别为(0.9±0.5)、(0.9±0.5)μmol/mg]明显低于G0组[(1.9±1.1)μmol/mg](P0.05),而G5组[(1.7±0.7)μmol/mg]不但没有降低,反而显著高于G3、G4组(P0.05);与G0组MMP(1 701±251)相比,G5组(1 156±216)显著降低(P0.05),而G1、G2、G3、G4组(分别为1 810±298、1 995±437、1 950±334、1 582±314)无明显变化。冷冻复苏后各组前向运动精子百分率和总活动率均较新鲜精液明显下降(P0.01),B1组前向运动精子百分率[(3.2±2.3)%]较B0组[(0.8±0.6)%]明显改善(P0.05);B1组精子总活动率[(43.0±9.5)%]较B0组[(26.5±11.4)%]明显改善(P0.05);B1组ROS[(34.6±12.3)]和B2组ROS[(37.0±10.5)]均较B0组[(56.9±14.3)]显著下降(P0.05),B1组MDA[(1.4±0.5)μmol/mg]和B2组MDA[(1.4±0.6)μmol/mg]均较B0组[(2.6±1.0)μmol/mg]显著下降(P0.05),B1组MMP[(1 010.0±131.5)]和B2组MMP[(880.6±128.6)]均显著高于B0组[(721.1±24.8)](P0.05)。结论:在精液冻存液中添加200 nmol/L的Mito Q能有效提高人精子质量,可作为精液冷冻保护添加剂用于精液的冷冻保存。     

高、低生育力捐精者复苏精液功能指标的比较性研究(附40例报告)

目的:探讨可以全面有效评估捐精者生育力的精子功能指标,运用于复苏精液标本的筛选,旨在提高辅助生殖技术成功率。方法:根据捐精者精液使用的妊娠结局,收集上海市人类精子库高、低生育力捐精者的冷冻精液标本各20例,比较两组精液标本复苏后的精子浓度、活力、正常形态率、顶体完整率、DNA完整性以及线粒体膜电位。结果:高、低生育力组精液复苏经系列评估后,正常形态率分别为(18.50±6.10)%、(14.42±6.44)%;顶体完整率分别为(86.17±4.49)%、(80.04±7.52)%;精子DNA碎片率分别为(9.21±3.22)%、(15.72±8.20)%,以上指标经统计学分析两组之间具有显著性差异(P0.05)。但线粒体膜电位高生育力组[(56.75±18.80)%]与低生育力组[(52.23±18.86)%]之间无显著性差异(P0.05)。精子线粒体膜电位与精子活力呈显著正相关(r=0.760,P0.05),其他功能指标与精子浓度、活力无显著相关。结论:精子浓度、活力与正常形态率、顶体完整率以及DNA完整性可以有效评估捐精者复苏精液生育能力。     

抗坏血酸盐、过氧化氢酶改善冻融人精子质量的研究

目的 探讨抗氧化剂--抗坏血酸盐、过氧化氢酶(catalase,CAT)、超氧化物歧化酶(superoxide dismutase,SOD)对冻融人精子质量的影响.方法 30份健康可生育男性精液分别添加改良人精子冷冻保护液,依所添加的抗氧化剂及终浓度分7组:未添加者为阴性对照组,余为抗坏血酸盐300、600 μmol/L组,CAT 200、400 U/ml组,SOD 200、400 U/ml组.检测各组精液冻融前后常规参数,冻融后活性氧(reactive oxidative species,ROS)水平、线粒体膜电位(△Ψm)和早期凋亡事件(Ann+PI-%、Ann-PI-%).结果 ①冻融后各组a+b级精子均比冷冻前下降(P＜0.01),但抗坏血酸盐300 μmol/L组与2种浓度的CAT组a+b级精子(43.5±10.0)%、(43.9±8.2)%、(44.3±9.4)%下降少于对照组(38.1±7.9)%,P＜0.05、P＜0.01、P＜0.01;相对应组的精子活率复苏率分别为(67.2±14.1)%、(68.4±13.8)%、(68.8±14.8)%,也高于对照组(58.8±10.1)%,P＜0.05、P＜0.01、P＜0.01;而这3组ROS水平(29.6±12.8)%、(30.0±11.2)%、(31.1±11.0)%则分别低于对照组(36.7±17.0)%,P值均＜0.05.②2种浓度CAT组的△Ψm(34.6±12.9)%、(32.9±11.2)%均高于对照组(27.5±10.8)%,P＜0.01、P＜0.05;而且低浓度抗坏血酸盐组和CAT组凋亡(Ann+PI-%)的精子(15.3±3.0)%、(15.6±2.2)%,以及未出现凋亡(Ann-PI-%)的活精子(14.0±3.8)%、(13.2±2.6)%分别低于对照组(18.1±3.9)%(P值均＜0.01)和高于对照组(10.1±4.0)%(P值均＜0.01).余实验组的检测指标与对照组相比,差异无统计学意义(P＞0.05).③冻融后各实验组a+b级精子,抗坏血酸盐600 μmol/L组、2种浓度CAT组、SOD 400 U/ml组的△Ψm,以及抗坏血酸盐组、CAT 200 U/ml组、SOD 200 U/ml组的Ann-PI-%均分别与对应组的ROS水平呈负相关;而抗坏血酸盐组、CAT 200 U/ml组的Ann+PI-%则与对应组的ROS水平呈正相关,P＜0.05或P＜0.01.结论 在精液冷冻保护剂中添加一定浓度的抗坏血酸盐、CAT可改善冻融人精子质量.     

维生素E和B12对冷冻精子活力和DNA的保护作用

目的探讨维生素E(Vit E)和Vit B12对冷冻精子活力和DNA的保护作用。方法收集在我院生殖医学中心就诊的32例正常男性精液标本,按照添加维生素的不同分为3组:对照组:精液中只添加常规冷冻保护剂;Vit E组:添加常规冷冻保护剂和5mM的VitE;Vit B12组:添加常规冷冻保护剂和0.5%的Vit B12。比较3组精子复苏后的精子活动力、存活率、顶体酶活性、精子DNA碎片率(SDF)等指标。结果经液氮冷冻72h复苏后,Vit E组活动力(a+b)级的精子数、精子存活率均显著高于对照组(P0.01);顶体酶活性在各组间比较无显著性差异(P0.05);Vit E组和Vit B12组的SDF[分别为(12.16±0.50)%、(13.02±0.48)%]均显著低于对照组的(15.18±0.78)%(P0.01);Vit E组的精子DNA平均晕轮直径[(6.76±0.14)μm]显著高于对照组[(6.09±0.18)μm](P0.01),Vit B12组与对照组比较无显著性差异(P0.05)。结论精子冷冻保护剂中添加适当浓度的Vit E可以缓解冻融过程对精子造成的伤害,在一定程度上提高冻融后精子活动力、存活率及精子DNA完整性。     

左卡尼汀对冷冻精子运动参数和精子线粒体功能的影响

目的:探讨左卡尼汀(LC)对人冷冻精子的影响。方法:将每份供精志愿者精液分为6组:新鲜精液组(FE组);常规冷冻组(Non-LC组,冷冻保护剂中未添加LC); LC 1～4组,冷冻保护剂中LC浓度分别为:1、2. 5、5、10 mmol/L。通过观察冷冻复苏后精子活力和运动参数改变,筛选最佳LC工作浓度。伊红-苯胺黑染色法评估精子质膜完整性(PMI),JC-1法评估精子线粒体膜电位(MMP),DCFH-DA法评估活性氧(ROS),探索LC对精子冷冻损伤的影响机制。结果:与FE组相比,冷冻复苏后精子(Non-LC组和LC各组),前向运动精子百分率(PR%)和运动参数(VAP、VSL、VCL)均明显下降(P 0. 05)。与Non-LC组相比,LC 3组PR%[(47. 0±4. 3)%vs(41. 9±4. 6)%,P=0. 0261)]和VAP [(38. 9±4. 2)μm/s vs (34. 9±2. 6)μm/s,P=0. 0152)]改善明显,确定5 mmol/L为实验最佳LC工作浓度。与FE组比较,Non-LC组冷冻复苏后精子PMI[(52. 7±5. 7)%vs (75. 5±5. 4)%]、MMP[(44. 5±3. 5)%vs(57. 3±4. 4)%]明显降低(P 0. 01),ROS[(12. 5±3. 9)%vs(6. 8±2. 4)%]明显升高(P 0. 01);与Non-LC组比较,LC组精子PMI[(70. 1±8. 2)%]和MMP[(50. 3±3. 4)%]明显升高(P 0. 01、0. 05),ROS[(8. 4±5. 3)%]明显降低(P 0. 05)。结论:LC可能通过降低精子ROS,提高精子MMP,保护精子质膜,改善冷冻后精子活力和运动参数。     

冷冻保存对人类精子线粒体DNA的影响

目的探讨常规精液冷冻技术对人类精子线粒体DNA的影响。方法收集符合精子库捐精条件的正式志愿者精液样品,将每份样品分为2份:1份进行精液冷冻复苏处理,为实验组;1份新鲜精液,为对照组。采用Markler计数板联合CASA法评估冷冻复苏前后精子活力;两组精液均采用实时荧光定量PCR和长链PCR技术,分别检测精子线粒体DNA的拷贝数和完整性。结果共收集22份精液标本,纳入志愿者年龄为(27.8±3.0)岁,禁欲天数(6.1±0.9)d;精液体积(5.0±1.5)ml,精子浓度(75.8±15.8)×106/ml,前向运动精子百分比为(68±6)%,总活动精子复苏率为(72±8)%。冷冻保存后,精子活力显著降低:前向运动精子百分比减少[(49.0±6.5)%vs.(68.0±6.1)%,P0.05),平均路径速率(VAP)[(35.8±6.8)vs.(46.8±9.5),P0.05]、直线速率(VSL)[(27.3±3.3)vs.(35.1±8.3),P0.05]和曲线速率(VCL)[(57.6±6.9)vs.(91.8±10.2),P0.05]较前下降。与新鲜精液相比,冷冻复苏后精子的线粒体DNA拷贝数显著增加[(10.12±8.41)vs.(5.66±5.53),P0.05],完整性比较无统计学差异[(29.69±15.04)vs.(32.78±16.0),P=0.077]。结论在正式捐精志愿者人群内,常规精液冷冻技术降低精子活力,增加人类精子mtDNA的拷贝数,但未显著改变mtDNA的完整性。     

手机辐射对离体精子质量及DNA甲基化的影响

目的:研究手机辐射对男性离体精液的影响及其相关机制。方法:依照WHO《人类精液检查与处理实验室手册》第5版的标准,随机选择97例精液常规参数正常的男性作为研究对象,并将每例研究对象的精液一式2份为对照组和辐射组。辐射组与对照组相比,除了给予一定剂量(1 950 MHz,SAR 3.0 W/kg,时间3 h)的辐射外,其他条件和处理均相同。从精液常规参数、顶体反应能力、精子凋亡程度以及DNA甲基化水平方面,综合分析手机辐射对精液质量的影响。结果:与对照组相比,辐射组前向运动精子百分率显著降低[(36.64±16.93)%vs(27.56±16.92)%,P<0.01],精子活率显著降低[(63.72±16.35)%vs(54.31±17.35)%,P<0.01],精子头部缺陷率显著升高[(69.92±4.46)%vs(71.17±4.89)%,P<0.05],而顶体反应率无统计学差异[(66.20±6.75)%vs(64.50±3.47)%,P>0.05]。与对照组相比,辐射组精子早期凋亡率显著升高[(4.44±5.89)%vs(6.89±9.84)%,P<0.05]。辐射对精子的父源印记基因H19印记基因的印记控制区域及母源印记基因Kv DMR1的DNA甲基化丢失率[(0.60±0.02)%vs(1.40±0.03)%,(0.00±0.00)%vs(1.80±0.03)%,P均>0.05)]均无显著影响。结论:手机辐射可致前向运动精子百分率、存活率显著降低,精子头部缺陷率和精子早期凋亡率显著升高。     

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.     

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.     

Intravenous endotoxin does not increase tissue extravasation of albumin in rats

Background : It is unclear whether activation of the inducible nitric oxide synthase (iNOS) increases or decreases the extravasation of plasma.
Methods : Chloralose anaesthetised male Wistar rats received E. coli lipopolysacharide (LPS), 3 mg kg^-1 i.v., or the corresponding volume of saline, 3 or 5 h before the end of the experiment. Mean arterial pressure (MAP) and heart rate (HR) were recorded. Tissue clearance of radio-labelled albumin, during the last 2 h of each experiment, was determined by a double-isotope method. In separate animals, the serum concentration of nitrite and nitrate was determined, 5 h after LPS or the solvent.
Main Results : LPS initially decreased MAP and lastingly increased HR. In the 3-h LPS animals (n=8), tissue plasma clearance was lower in the heart and calf muscle and increased only in diaphragm, compared to corresponding control animals (n=8). In the 5-h LPS rats, clearance was lowered (n=8) in the entire gastrointestinal tract and in testes, compared to controls (n=8). The serum nitrite/nitrate concentration was higher in animals given LPS (n=6) than in controls (n=6).
Conclusion : After LPS, tissue clearance of albumin was not increased in any major tissue, in spite of increased serum levels of NO end products. Apparently, after activation of iNOS, the augmented release of NO is not necessarily associated with increased albumin extravasation.     

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery: A randomised, double-blind, cross-over study with and without adrenaline

Background: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. Methods: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml · h^?1 of bupivacaine 1 mg · ml^?1, fentanyl 2 μg · ml^?1, and adrenaline 2 μg · ml^?1 were included. On the 1^st and 2^nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. Results: The number of hypaesthetic dermatomal segments decreased (P <0.001) and pain intensity at rest and when coughing increased (P <0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15–20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng · ml^?1 (P <0.01), and there was more sedation during the period without adrenaline. Conclusions: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.     

Utilisation des médicaments prokinétiques en réanimation : indications et limites ?

Enteral feeding is often limited by gastric and intestinal motility disturbances in critically ill patients, particularly in patients with shock. So, promotility agents are frequently used to improve tolerance to enteral nutrition. This review summaries the pathophysiology, presents the available pharmacological strategies, the clinical data, the counter-indications and the principal limits. The clinical data are poor. No study demonstrates a positive effect on clinical outcomes. Metoclopramide and erythromycin seems to be the more effective. Considering the risk of antibiotic resistance, the first line use of erythromycin should be avoided in favor of metoclopramide.     

Anesthésie générale chez l’enfant : quid des pratiques en 2010 ?

Introduction

The practice of pediatric anesthesia requires a regular update of scientific knowledge and technical skills. To provide the most adequate Continuing Medical Education programs, it is necessary to assess the practices of pediatric anesthesiologists. Thus, the objective of this survey was to draw a picture of the current clinical practices of general anesthesia in children, in France.

Material and methods

One thousand one hundred and fifty questionnaires were given to anesthesiologists involved in pediatric cases. These questionnaires collected information on various aspects of clinical practice relative to induction, maintenance, recovery from general anaesthesia and also classical debated points such as children with Upper Respiratory Infection (URI), emergence agitation, epileptoid signs or anaesthetic management of adenoidectomy. Differences in practices between CHG (general hospital), CHU (teaching hospital), LIBERAL (private) and PSPH (semi-private) hospitals were investigated.

Results

There were 1025 questionnaires completed. Fifty-five percent of responders worked in public hospitals (CHG and CHU); 77% had a practice that was 25% or less of pediatric cases. In children from 3 to 10 years: 72% of respondents used always premedication and two thirds performed inhalation induction in more than 50% of cases. For induction, 53% used sevoflurane (SEVO) at 7 or 8%. Respondents from LIBERAL used higher SEVO concentrations. Tracheal intubation was performed with SEVO alone (37%), SEVO and propofol (55%) and SEVO with myorelaxant (8%), 93% of respondents used a bolus of opioid. For maintenance, the majority of respondents used SEVO associated with sufentanil; desflurane and remifentanil were more frequently used in CHU. Two thirds of respondents used N₂O. Depth of anesthesia was commonly assessed by hemodynamic changes (52%), end tidal concentration of halogenated (38%) or automated devices based on EEG (7%). In children with URI, 98% of respondents used SEVO for anesthesia. To control the airway 42% used a tracheal tube, 30% a laryngeal mask and 20% a facial mask. Emergence agitation was an important concern for two thirds of respondents, while epileptoid signs were considered as important by only 20%. Eighty-nine percent of respondents practiced anesthesia for adenoidectomy. Anesthesia was induced by inhalation of SEVO 7–8% (41%), 6% (39%) or 4% (12%), 66% put an intravenous line (less frequently in LIBERAL). 67% of the responders managed adenoidectomy without any device to control the airway (more frequently in LIBERAL), 32% administrated a bolus of opioid (less frequently in LIBERAL).

Discussion

This survey demonstrated that the practices regarding general anesthesia in children are relatively homogenous. Most of the differences appeared between LIBERAL and the others structures; the anaesthetic management for adenoidectomy illustrates these findings.     

Intérêt d’une rééducation précoce pour les patients neurologiques

Rehabilitation improves the functional prognosis of patients after a neurologic lesion, and tendency is to begin rehabilitation as soon as possible. This review focuses on the interest and the feasibility of very early rehabilitation, initiated from critical care units. It is necessary to precisely assess patients’ impairments and disabilities in order to define rehabilitation objectives. Valid and simple tools must support this evaluation. Rehabilitation will be directed to preventing decubitus complications and active rehabilitation. The sooner rehabilitation is started; the better functional prognosis seems to be.     

Risiko Schlaganfall — Öffentlichkeitsarbeit und Aufklärung dringend erforderlich

Zusammenfassung Das wesentliche — und zugleich noch wenig ausgeschöpfte — Potenzial der Schlaganfallmedizin liegt in der langfristigen Prophylaxe. Durch Beeinflussung von Lifestylefaktoren wie Ernährungsgewohnheiten, Zigarettenkonsum und körperlichem Training durch entsprechende Aufklärung ließe sich ein erheblicher Teil an zerebralen Ereignissen vermeiden. Ein weiterer in Deutschland noch zu wenig beachteter Faktor ist die konsequente Blutdruckeinstellung. Breitgestreute Aufklärung könnte außerdem potenziellen Patienten helfen, bereits auftretende Warnsymptome wie die transiente ischämische Attacke richtig einzuschätzen, um eine rechtzeitige Behandlung zu ermöglichen.