一种提高犬胰岛体外培养质量的方法

目的研究提高犬胰岛体外培养质量的方法。方法将犬胰岛分别进行普通培养 (A组)、常温(37℃)微重力培养(B组)和低温(26℃)微重力培养(C组),分别培养3、7、14和21 d, 并检测各组胰岛培养后收获率、存活率和功能。结果不同方法培养21 d后,B组和C组平均胰岛收获率为(66．2±4．1)％和(81．3±4．8)％高于A组的胰岛收获率(50．5±2．9)％,P<0．05。A组胰岛存活率降至(27．7±3．5)％,与B组的(49．7±3．2)％和C组的(64．8±4．7)％比较,P<0．05。 B组和C组DNA含量及胰岛素含量均维持较高的水平,B组和C组胰岛素储备能力较A组高,胰岛索刺激指数分别为(3．30±0．70)、(5．48±1．00)和(2．33±0．50),差异有统计学意义(P< 0．05)。结论低温微重力三维培养胰岛是提高胰岛培养质量的好方法。     

低温微重力培养对大鼠胰岛细胞质量影响的实验

目的:研究低温微重力对大鼠胰岛移植质量的影响，以期减少体外培养对胰岛活性和数量的影响，提高胰岛移植质量。方法:将分离纯化的大鼠胰岛分为3组：大鼠新鲜胰岛移植组（于移植前在普通培养基中培养21 d,对照组）；实验1组（大鼠新鲜胰岛在37 ℃ RCCS中培养21 d）；实验2组（新鲜大鼠胰岛在26 ℃ RCCS中培养14 d后复温至37 ℃继续在37 ℃ RCCS中培养7 d）。　观察各种培养液中的胰岛素含量。并将上述3个实验组不同条件培养的胰岛分别以2000IEQ胰岛移植量植入糖尿病大鼠体内，并观察10周。结果:实验2组的胰岛存活率、胰岛素分泌水平及胰岛素刺激指数均高于对照组和实验1组，差异有统计学意义(P＜0.05)。21 d时实验2组胰岛存活率高达(67.4±4.6)%，而对照组和实验1组胰岛存活率分别降至(28.1±3.3)%和(50.3±3.5)%，3组间差异有统计学意义(P＜0.05)。给糖尿病大鼠移植实验1，2组的胰岛后均能控制血糖至正常水平，但实验2组胰岛移植对糖尿病大鼠7 d内血糖控制优于实验1组；对照组血糖控制差，3组间两两比较均有统计学差异（均P＞0.05）。结论:大鼠胰岛经低温微重力培养后移植，可以明显提高1型糖尿病大鼠的治疗效果。     

Sertoli细胞与成人胰岛细胞共同培养的研究

目的观察塞尔托利（Sertoli）细胞对体外培养的成人胰岛细胞形态、存活率及功能的影响。方法胰腺、睾丸取自志愿捐赠的成年男性尸体多器官供者,共12例。分离纯化后的成人胰岛细胞分为单独培养组和共同培养组,单独培养组取成人胰岛细胞单独培养,共同培养组为成人胰岛细胞＋Sertoli细胞共同培养,均在RPMI1640培养液培养14d,采用倒置相差显微镜观察胰岛细胞形态,比较两组的胰岛细胞存活率、胰岛素分泌量和胰岛素刺激指数。结果培养14d后,共同培养组胰岛细胞存活率为（90±3）%,较单独培养组的（57±4）%明显提高（P〈0.01）,胰岛细胞的形态亦较单独培养组完整。共同培养组胰岛细胞始终对葡萄糖刺激保持较高的敏感度,而单独培养组胰岛细胞对葡萄糖刺激的敏感度随时间的延长明显降低（P〈0.05）。培养14d后,共同培养组的胰岛素分泌量为（249±12）mIU/L、胰岛素刺激指数为8.15±0.64,而单独培养组则分别为（47±7）mIU/L和1.68±0.34,两组比较差异有统计学意义（均为P〈0.01）。结论成人胰岛细胞与Sertoli细胞共同培养可以提高胰岛细胞的存活率,改善胰岛细胞的功能。     

人工生物胰的体外分泌功能研究

目的 探讨海藻酸钠-氯化钡微囊对成人胰岛细胞体外分泌功能的影响.方法 对6例成人胰腺组织称重后采用V型胶原酶消化法分离,采用Ficoll间断密度梯度离心纯化法纯化,采用DTZ染色显微镜下评价胰岛细胞的数量、纯度.采用海藻酸钠氯化钡为材料包裹成人胰岛,体外培养及放射免疫法测定培养液中基础胰岛素浓度.结果 成人胰腺经胶原酶消化分离后,胰岛平均收获量(3600±447)个胰岛/g胰腺；Ficoll间断密度梯度离心纯化后,每克胰腺组织平均收获量(2140±207)个胰岛,纯度大于70％；成人胰岛细胞培养2、4、6d后,微囊化组第2、4、6天的基础胰岛素平均浓度(每100个胰岛单位mU/L)分别为3.302±1.63、3.504±1.10、2.921±1.13,未微囊化组的基础胰岛素平均浓度(每100个胰岛单位mU/L)分别为3.814±1.49、4.175±1.60、3.617±1.34,两组基础胰岛素浓度差异无统计学意义(P＞0.05).结论 人工生物胰具有良好的体外分泌功能,包裹成人胰岛的海藻酸钠-氯化钡微囊对胰岛体外分泌胰岛素的功能无影响.     

扶芳藤含药血清对大鼠胰岛细胞的保护机制

目的探讨扶芳藤含药血清对大鼠胰岛细胞的保护作用及其机制。方法将40只雄性SD大鼠随机分为5组,每组8只,包括对照组(正常大鼠胰岛细胞予正常大鼠血清培养)、缺血预处理组(获取胰腺前阻断腹主动脉再开放,胰岛细胞予正常大鼠血清培养)、扶芳藤治疗组(正常大鼠胰岛细胞予大鼠扶芳藤含药血清培养)、扶芳藤组和空白组(正常大鼠分别予扶芳藤提取物或蒸馏水灌胃,用于制备大鼠血清)。采用双硫腙(DTZ)染色法观察并计算胰岛数量;采用吖啶橙(AO)/碘化丙啶(PI)染色法,计算胰岛细胞存活率;采用胰岛素释放实验计算刺激指数(SI)来评价胰岛细胞功能;采用谷胱甘肽(GSH)及一氧化氮(NO)试剂盒测定胰岛细胞内GSH、NO含量;采用逆转录聚合酶链反应(RT-PCR)法检测诱导型一氧化氮合酶(iNOS)信使核糖核酸(mRNA)的表达水平。结果经DTZ染色后胰岛细胞呈特异性猩红色,各组间胰岛细胞数量比较,差异无统计学意义(均为P0.05)。随培养时间延长,各组胰岛细胞活性均逐渐降低,分离培养72 h后,与对照组比较,扶芳藤治疗组细胞存活率更高,差异有统计学意义(P0.05)。胰岛素释放实验检测结果提示,与对照组相比,缺血预处理组及扶芳藤治疗组的SI均升高,差异均有统计学意义(均为P0.05)。与对照组比较,缺血预处理组及扶芳藤治疗组胰岛细胞的GSH含量均升高、NO含量均降低、iNOS mRNA表达水平均降低,差异均有统计学意义(均为P0.05)。结论扶芳藤能通过提高GSH、降低iNOS表达及NO产生,提高胰岛细胞存活率,增强胰岛功能。     

高压氧微重力培养提高冻存胰岛质量和移植效果的实验研究

目的 探讨胰岛冻存前后经高压氧细胞旋转培养系统(HORCCS)培养后移植入糖尿病大鼠能否提高胰岛移植的效果.方法 将分离纯化的大鼠胰岛分为:A.体外实验组:将各组大鼠胰岛经HORCCS培养或普通培养30 d,检测细胞内DNA和胰岛素含量,胰岛存活率,胰岛素分泌水平.B.胰岛移植实验组:将各组大鼠胰岛经HORCCS培养或普通培养7d,然后移植,观察移植受体血糖和胰岛素水平.电镜观察各胰岛移植实验组中培养7 d时的胰岛的超微结构改变.结果 经高压氧 RCCS培养14 d的胰岛存活率及胰岛素分泌水平高于普通培养组(P<0.05).移植了经HORCCS培养的胰岛后,受体血糖在移植后2周即恢复为正常值,并维持到移植后10周.全部受体维持正常血糖耐受曲线.电镜下可见经HORCCS培养后,冻存复苏胰岛表面形成微小的孔道.结论 胰岛冻存前后经高压氧RCCS培养后可以建立营养输送管道,不但有利于氧和营养物质的运输,更有利于胰岛内细胞的均匀一致的冻存,从而减少冻存对胰岛的损害,提高胰岛的分泌活性和成活率.     

提高冻存胚胎胰岛移植效果的实验研究

目的探讨三维组织细胞旋转培养系统(RCCS)对胚胎胰岛冻存复苏后质量的影响。方法将胚胎胰岛平均分为3组,实验组1、2为胚胎胰岛冻存前后分别用RCCS培养和普通培养,对照组新鲜胰岛经RCCS培养。切取胚胎胰腺,胶原酶V消化,纯化。然后进行标准冻存步骤,复苏后继续培养。并检测各组胰岛数量、活性、胰岛素刺激实验结果。结果纯化后收获胰岛最多每个胚胎5012.73IEQ,最少2432.68IEQ,平均(3548.07±273.46)IEQ。微重力培养组胰岛细胞存活率、胰岛素释放量、胰岛素刺激指数等均高于普通培养组。移植经过微重力培养的(2000±1)%IEQ新鲜胚胎胰岛或冻存胚胎胰岛在移植后1周内可达100%纠正糖尿病。结论微重力旋转培养有利于胰岛细胞的生长繁殖,使胰岛具有更好的胰岛素分泌能力,该方法同胰岛冻存相结合,可以进一步提高胰岛的冻存效果,为胰岛库的成功建立探索出一条新的途径。     

微重力培养的新鲜和冻存胰岛联合移植治疗1型糖尿病

目的经微重力培养的新鲜和冻存胰岛联合移植提高1型糖尿病的治疗效果。方法将分离纯化的大鼠胰岛分为（1）体外实验组：实验组1．1：冻存的胰岛经微重力培养；实验组2．1：冻存的胰岛在普通培养基中培养；对照组1：新鲜大鼠胰岛经微重力培养。观察胰岛收获率和体外胰岛素分泌情况。（2）胰岛移植组：即将新鲜和冻存的胰岛经微重力或普通培养7d后分别移植入受体鼠体内，观察移植效果。结果经微重力培养的各组胰岛收获率、DNA含量和胰岛素含量高于普通组。普通培养组在培养后期胰岛素分泌明显下降，并且胰岛素刺激指数明显低于经微重力培养组（P〈0．05）。移植经过微重力培养的500 IEQ新鲜胰岛和1500 IEQ冻存胰岛在移植后1周内可达100％纠正糖尿病，全部受体维持正常血糖耐受曲线一直到观察结束。结论采用细胞内低温保存液（HTS）结合细胞冻存液（DMSO）对大鼠胰岛进行冻存前后经微重力培养可以明显提高胰岛冻存质量，是目前胰岛冻存的最佳选择。使经微重力培养的新鲜和冻存胰岛联合移植一次治愈糖尿病成为可能，并有效的节约了胰岛资源，提高了移植效果。     

胰岛素强化治疗对严重烧创伤患者胰岛素抵抗的影响

目的 探讨胰岛素强化治疗对严重烧(创)伤患者胰岛素抵抗的影响. 方法 将重庆市第三人民医院和第三军医大学西南医院2010年1月-2011年12月收治的60例严重烧(创)伤患者,按随机配对分组法分为2组,每组30例:试验组给予胰岛素强化治疗,将血糖水平控制在6.0～8.0 mmol/L;对照组行常规治疗.治疗前及治疗后1、3、7、10、14 d检测患者空腹血糖、血浆胰岛素水平.采用稳态评估法计算胰岛素抵抗指数和胰岛β细胞功能指数.对数据进行t检验、方差分析及LSD检验. 结果 治疗后1、3、7、10 d,试验组患者血糖水平分别为(6.8±1.4)、(6.7±1.3)、(5.8±1.9)、(5.4±1.6) mmol/L,明显低于对照组患者的(14.8±4.9)、(12.7±3.7)、(7.7±1.9)、(6.6±1.3) mmol/L,t值分别为12.453、11.386、5.563、4.731,P＜0.05或P＜0.01.治疗后3、7d,试验组患者血浆胰岛素水平分别为(14±5)、(10±3)mU/L,明显低于对照组的(16±4)、(13±4) mU/L,t值分别为4.212、4.364,P值均小于0.05.除对照组治疗后3d血糖水平外,2组患者治疗后各时相点血糖和胰岛素水平与治疗前比较,差异均有统计学意义(P值均小于0.01).治疗后1、3、7、10d,试验组患者胰岛素抵抗指数分别为1.60 ±0.80、1.46 ±0.70、0.96 ±0.21、0.90 ±0.23,显著低于对照组的2.15±1.35、2.21 ±1.21、1.50±0.95、1.17 ±0.66,t值分别为8.316、10.607、7.825、5.217,P＜0.05或P＜0.01.2组患者治疗后各时相点胰岛素抵抗指数均显著低于治疗前(P值均小于0.01).治疗后1、3、7d,试验组患者的胰岛β细胞功能指数分别为4.6±2.9、4.5±3.3、4.5±3.6,显著高于对照组的3.4±2.5、3.6±2.2、4.2±2.5,t值分别为8.243、7.914、4.338,P＜0.05或P＜0.01.2组中,仅对照组治疗后1、3d胰岛β细胞功能指数显著低于治疗前(P值均小于0.05). 结论 胰岛素强化治疗可以减轻严重烧(创)伤患者伤后胰岛素抵抗.     

氨基胍对大鼠胰岛保护作用的实验研究

目的 探讨在细胞因子与大鼠胰岛细胞共同培养过程中,诱导型一氧化氮合酶(iNOS)抑制剂氨基胍对胰岛细胞功能和存活的影响及其机理.方法 分离纯化大鼠胰岛,进行胰岛细胞培养.根据培养基中是否加入氨基胍或细胞因子IL-1β和TNF-α,按随机对照原则分为空白对照组(完全培养基)、细胞因子组(加IL-1β和TNF-α)、氨基胍组(加氨基胍)及氨基胍+细胞因子组(加氨基胍及细胞因子).检测指标包括: 培养液中NO水平、胰岛组织中iNOS活性、胰岛细胞存活情况(丫啶橙/溴乙锭染色)、胰岛细胞凋亡情况(TUNEL法)及胰岛功能(胰岛素释放试验).结果 与空白对照组比较,细胞因子组大鼠胰岛组织中iNOS的活性明显提高,培养液中NO的水平明显上升,同时胰岛细胞的存活率下降,大量细胞凋亡,胰岛素分泌明显减少(P＜0.01).与细胞因子组比较,氨基胍+细胞因子组的iNOS的活性[(3.17±0.51) U/ml比(38.93±4.72) U/ml]及NO水平[(50.5±10.4) μmol/L比(313.0±35.4) μmol/L]明显下降,胰岛细胞存活率活明显升高[(72.73±3.14)%比(57.07±5.07)%],凋亡率明显下降[(20.11±8.48)%比(41.17±6.87)%],胰岛素分泌指数明显升高(3.50±0.27比1.96±0.19),差异均有统计学意义(P＜0.01).结论 氨基胍通过抑制iNOS活性,控制NO过量产生,从而减轻细胞因子对胰岛的损害,改善胰岛的存活与功能.     

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.     

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.     

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.     

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.     

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.     

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.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.