人参总皂甙对高能冲击波肾细胞凋亡相关基因bcl-2和bax表达的影响及其临床意义

目的探讨人参总皂甙对高能冲击波肾细胞凋亡相关基因的影响。方法选用成年大耳白兔制备动物模型,将动物分为人参皂甙组、对照组,每组8只,冲击波次数为2300～2500次,工作电压10.5～12.0kV。体外冲击波碎石(ESWL)后48h分别处死动物,取右肾行免疫组织化学链霉素抗生物素蛋白过氧化物酶连结法(SP)染色。结果bcl-2的表达,用药组肾曲管上皮阳性细胞数为(87.6±17.1)个,而对照组为(22.6±8.2)个(P＜0.05）。Bax表达用药组阳性细胞数为(46.3±11.7)个,对照组(81.7±9.6)个（P＜0.05)。结论人参总皂甙可促使细胞凋亡抑制基因bcl-2高表达,相对抑制促进基因bax的表达,减少肾曲管上皮细胞凋亡。     

严重烫伤大鼠休克期淋巴循环动力学及淋巴液中肿瘤坏死因子α和白细胞介素6、8水平的变化

目的观察严重烫伤大鼠休克期淋巴管运动变化及淋巴液中肿瘤坏死因子(TNF)α、白细胞介素(IL)6 、IL-8水平的变化. 方法将36只雄性Wistar大鼠造成30%TBSAⅢ度烫伤后,随机分为补液组(18只)和未补液组(18只);另设对照组(6只,不烫伤).用放射免疫分析法检测各组大鼠淋巴液中TNF-α、IL-6、IL-8水平,利用倒置显微镜及录像系统观察大鼠伤后6、24、48 h的肠系膜淋巴管运动变化,计算淋巴管收缩频率.经乳糜池插管收集淋巴液,计算淋巴液流速并行组织学观察. 结果伤后6 h两组烫伤大鼠TNF-α、IL-6增多,24 h达高峰,此时补液组TNF-α(1.61±0.27)μg/L,IL-6(398±67)ng/L;未补液组TNF-α(1.86±0.34)μg/L,IL-6(572±97)ng/L,两组间比较差异,有统计学意义(P<0.01),且各时相点浓度均显著高于对照组(P<0.01).伤后24 h两组烫伤大鼠IL-8浓度开始升高,直至48 h升高更明显,此时补液组为(540.29±0.32)ng/L,未补液组为(863.48±0.16)ng/L,两组间比较差异有统计学意义(P<0.01),且显著高于对照组(P<0.01).两组烫伤大鼠淋巴管收缩频率较低,尤以伤后24 h为明显(P<0.01) , 淋巴液流速各时相点均升高(P<0.01) ;镜下见小肠绒毛中央乳糜管扩张. 结论严重烫伤大鼠休克期淋巴管扩张,运动频率减少,但淋巴液流速加快,淋巴液中TNF-α、IL-6、IL-8的水平升高.液体复苏能够改善淋巴循环.     

胰腺肿瘤缺血再灌注加微球栓塞后血清细胞因子的变化

目的探讨胰腺缺血再灌注加微球栓塞对鼠胰腺癌血清肿瘤坏死因子（TNF）-α、白细胞介素-1（IL-1）和λ-干扰素（IFN-λ）含量及肿瘤生长的影响。方法大鼠胰腺尾部胰腺肿瘤形成后,阻断及开放胰腺尾部主要供血血管脾下动脉各30min,并经脾下动脉注入微球栓塞微血管,然后结扎脾下动脉。分别于术前及术后14d采用酶联免疫吸附法测定血清TNF-α、IL-2和IFN-λ的含量及观察胰腺肿瘤体积的变化。结果胰腺肿瘤缺血再灌注加微球栓塞组（E组）术前血清TNF-α、IFN-λ和IL-2的含量和胰腺肿瘤体积与阳性对照组（B组）和胰腺肿瘤缺血组（C组）及胰腺肿瘤缺血再灌注组（D组）之间比较差异均无显著性（P>0.05）。术后14dE组血清TNF-α、IFN-λ和IL-2的含量〔（79.5±8.7)ng/L、(106.0±10.8)ng/L、(346.1±13.1)ng/L〕明显高于B组〔（30.5±3.5)ng/L、（76.7±5.8）ng/L、（137.5±8.1）ng/L〕、C组〔（53.6±6.3）ng/L、（91.4±7.3）ng/L、（203.4±7.9）ng/L〕和D组（P<0.01）;且D、E组肿胰腺瘤体积也明显小于B、C组。结论胰腺肿瘤缺血再灌注加微球栓塞可导致鼠胰腺肿瘤血清TNF-α、IFN-λ和IL-2含量明显升高,并可使胰腺肿瘤体积明显缩小,其效果明显优于单纯的胰腺肿瘤缺血或胰腺肿瘤缺血再灌注。     

PSA、PSAD和PSAT对前列腺癌诊断的比较

目的　比较前列腺移行带特异性抗原密度（PSAT）与前列腺特异性抗原（PSA）及前列腺特异性抗原密度（PSAD）在前列腺癌诊断中的意义。方法　对78例PSA4～20ng/ml的患者行前列腺穿刺活检后比较PSA、PSAD和PSAT指标。结果　78例中,病理诊断为前列腺癌(PCa)32例,良性前列腺增生(BPH)46例,二者PSA平均值分别为(14.32±1.46)ng/ml、(13.89±1.52)ng/ml,二者相比差别无显著性意义(P>0.05);PSAD平均值分别为0.43±0.14、0.36±0.17,二者相比差别有显著性意义(P<0.05);PSAT平均值分别为0.75±0.19、0.31±0.06,二者相比差别有非常显著性意义(P<0.01)。结论　PSAD和PSAT对预测PSA<20ng/ml的患者是否患前列腺癌有较大帮助,特别是PSAT更为准确。     

过氧化氢诱导人脐静脉内皮细胞株的凋亡及其调控的研究

目的探讨过氧化氢(H2O2)对人脐静脉内皮细胞株（ECV-304）的损伤作用及其可能机制。方法对体外培养的ECV-304,采用形态学、琼脂糖凝胶电泳及流式细胞术等方法,观察过氧化氢的损伤方式及调控基因蛋白Fas和bcl-2的影响。结果一定剂量(100、300、500mmol/L)的过氧化氢刺激后,内皮细胞发生凋亡,凋亡率分别是8.38±2.19、14.60±2.75、20.63±3.89,与对照组2.38±0.96相比,差异具有非常显著性(P<0.01)。同时Fas蛋白显著增加,分别为17.03±5.59、20.38±7.02、27.60±4.55,bcl-2蛋白明显下调,分别为19.35±3.36、18.75±3.33、13.05±2.93,与对照组相比差异均具有显著性（P<0.05或P<0.01)。结论一定剂量的过氧化氢对血管内皮细胞的损伤可通过诱导Fas表达增加,bcl-2表达下调,而致细胞凋亡。     

重症急性胰腺炎器官损伤与内皮素-1mRNA表达的关系及丹参的影响

目的探讨重症急性胰腺炎(SAP)内皮素-1(ET-1)mRNA表达对胰腺及肺、肾损伤的作用机制,观察丹参注射液对ET-1mRNA表达及病情转归的影响。方法将Wistar大鼠随机分为模型组(n=15)、丹参组(n=15)、对照组(n=15)。建立SAP模型后,丹参组动物立即肌肉注射丹参注射液(每日2ml/kg体重),每6h1次,共给药4次。对照组仅行假手术。各组动物在术后24h测血淀粉酶、ET-1和腹水量。使用原位杂交和图像分析检测胰、肺、肾ET-1mRNA的表达强度,并观察胰、肺、肾病理变化。结果模型组血中淀粉酶(2156.05±355.87)U/L和腹水量(9.87±2.34)ml显著高于丹参组(1439.21±332.99)U/L、(5.27±2.81)ml和对照组(215.67±37.27)U/L、0ml(P<0.01)。模型组血中ET-1(185.47±20.80)ng/L高于丹参组(164.27±18.53)ng/L和对照组(72.90±17.27)ng/L(P<0.05,P<0.01)。模型组胰、肺、肾中ET-1mRNA表达显著高于丹参组(P<0.01)。丹参组胰、肺、肾病理改变较模型组减轻。结论SAP时胰腺的ET-1mRNA高表达导致ET-1过度生成并可能继发引起肺、肾病理损害。丹参能抑制胰腺的ET-1mRNA的过度表达,减轻血管内液体丢失,改善血流动力学,从而对胰腺及肺、肾组织起保护作用。     

丙氨酰-谷氨酰胺二肽保护大鼠肝脏缺血再灌注损伤的实验研究

目的探讨丙氨酰-谷氨酰胺二肽(Ala-Gln)对肝脏缺血再灌注损伤(HIRI)的保护作用.方法采用大鼠HIRI模型(Pringle's法阻断入肝血流30 min),分谷氨酰胺组(G组)及对照组(C组),检测再灌注后血清肝生化酶、肝组织还原型谷胱甘肽(GSH)及超氧化物歧化酶(SOD)水平,对肝组织进行光镜与电镜检查,并计算术后24 h生存率.结果再灌注1h,G组血清ALT(499.25±120.84)U/L、LDH(6 956.00±2 443.93)U/L的水平均显著低于C组(ALT823.56±328.71,P<0.05;LDH11 715.31±2 993.50,P<0.01);再灌注24 h,两组血清ALT、LDH的水平均有显著恢复,但G组(ALT176.69±151.84;LDH415.38±213.68)水平仍显著低于C组(ALT548.25±257.25;LDH1 958.50±687.32;P<0.01).再灌注1 h及24 h,G组GSH的水平分别为(1 216.09±152.78)μg·g-1·p、(899.73±57.75)μg·g-1·p,均明显高于C组(分别为856.68±117.64,P<0.01;800.50±94.79,P<0.05);两组SOD的活性无统计学差异.G组肝脏组织学与细胞学损害均明显轻于C组.G组术后24h生存率为78.57%(11/14),明显高于C组的45.45%(10/22)(P<0.05).结论 Ala-Gln(Gln)对HIRI具有保护作用,而这种保护作用部分是通过维持肝脏组织中GSH的含量来介导的.     

地塞米松治疗急性坏死性胰腺炎的实验研究

目的探讨地塞米松治疗急性坏死性胰腺炎(ANP)的机理.方法经胰胆管逆行注射牛磺胆酸钠法诱导SD大鼠ANP,治疗组(n=24)模型诱导30 min后注射地塞米松0.2 mg/100 g鼠重,对照组(n=24)注射等量生理盐水,两组分别于4 h和12 h各处死8只鼠测血清肿瘤坏死因子α(TNFα)、淀粉酶,并行胰腺坏死程度评分、检测胰腺腺胞细胞凋亡,余下8只鼠作生存期观察.结果治疗组4 h、12 h TNFα分别为(17.8±2.7) pg/ml和(8.5±1.6) pg/ml,胰腺腺胞细胞凋亡指数分别为(36.94±4.12)%和(32.79±3.31)%,生存时间为(33.4±21.5) h; 对照组上述各项指标依次为(53.6±18.7) pg/ml和(37.2±11.1) pg/ml (P<0.01)、(4.37±1.24)%和(5.12±2.11)%(P<0.01)及(14.6±5.7) h (P<0.01),两组胰腺坏死程度评分差异有显著性意义(P<0.01).结论地塞米松能通过抑制TNFα调控细胞凋亡,细胞凋亡对胰腺具有保护作用.     

严重腹腔感染时大鼠胃黏膜血流量和Na+-K+-ATP酶活性变化对胃黏膜电位差的影响

目的探讨严重腹腔感染状态下大鼠胃黏膜血流量和Na+-K+-ATP酶活性变化对胃黏膜电位差的影响. 方法利用大鼠盲肠结扎穿孔造成腹腔严重感染动物模型,应用激光多普勒微循环血流计和电生理记录仪检测穿孔前和穿孔后3、6、12、24、48 h 胃黏膜血流量和胃黏膜电位差变化;应用生化法测定各时相大鼠胃黏膜Na+-K+-ATP酶活性. 结果胃黏膜血流量(mV)在盲肠穿孔后3 h (43.7±2.8)与对照组(57.9±2.7)相比明显降低(P<0.05),12 h(31.9±2.6)降至最低(P<0.01),24 h(44.7±2.7)开始回升,48 h(52.9±2.8)仍低于对照组.Na+-K+-ATP酶活性(nmol pi/min/mg蛋白)在盲肠穿孔后3 h(113±14)较对照组(153±12)显著降低(P<0.05),12 h(92±10)降至最低(P<0.01),仅为对照组(153±124)的48.5%,48 h(128±13)仍未恢复正常.胃黏膜电位差(mV)在盲肠穿孔后 6 h(15.2±1.4)较对照组(23.1±1.6)显著下降(P<0.05),12 h(11.6±1.4)降至最低(P<0.01),24 h(17.0±1.5)仍显著低于对照组[(22.6±1.6),P<0.05],48 h(18.9±1.5)显著低于对照组[(22.4±1.5),P<0.05]. 结论严重腹腔感染状态下胃黏膜血流量减少和Na+-K+-ATP酶活性降低是引起大鼠胃黏膜屏障功能受损的主要原因.     

参附注射液对兔脊髓缺血损伤保护作用的量效关系研究

目的探讨参附注射液对脊髓缺血性损伤保护作用的剂量效应关系。方法24只雄性新西兰大白兔,随机分为四组A组(n=6),单纯缺血再灌注组,B组(n=6)、C组(n=6)和D组(n=6)分别于缺血前30min内持续恒速静脉输入参附注射液5ml·kg-1、10ml·kg-1、20ml·kg-1;采用肾下主动脉阻断法造成脊髓缺血(20min);术后观察神经功能变化并记录再灌注1h、4h、8h、12h、24h和48h神经功能评分,再灌注48h处死动物后取脊髓(L5～7)标本行病理学观察。结果术后神经功能评分除再灌注1hD组与A组之间无显著性差异,其余各时间点B组、C组和D组均明显高于A组(P<0．05),B组、C组和D组间则无显著性差异(P>0．05),且48h时各组神经功能评分分别为A组0．5±0．8、B组3．2±0．9(P<0．001)、C组3．0±1．0,(P<0．001)和D组2．7±0．8(P<0．05);再灌注48h脊髓前角正常运动神经元计数B组(78±25,P<0．001)、C组(41±23,P<0．05)和D组(42±27,P<0．05)均高于A(8±7)组,B组与C组、D组间亦有显著性差异(P<0．05)。结论参附注射液对脊髓缺血性损伤有保护作用,但无明显剂量效应关系。     

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.     

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.     

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.