再生小室内间断给予蛋白激酶C激动剂对周围神经表达NGF及损伤修复的影响

目的探讨大鼠坐骨神经再生小室内间断给予蛋白激酶C激动剂-佛波醇酯(phorbol-12-myristate-13-acetate,PMA)后,坐骨神经蛋白激酶C(protein kinase C, PKC)mRNA、神经生长因子(nerve growth factor, NGF)mRNA表达变化规律及轴突数目变化. 方法 SD大鼠42只行双侧坐骨神经中段切断约5 mm,"T"形硅胶管套接,随机分为6组,分别为损伤1、3天,1、2、3和4周组.右侧间断给予1×10-9mol/L PMA(PMA侧);左侧注射等量生理盐水(对照侧).采用组织切片核酸原位杂交(in situ hybridization,ISH)技术检测各组术后各不同点PKC mRNA和NGF mRNA在坐骨神经表达的动态变化及轴突数目变化. 结果对照侧大鼠坐骨神经PKC mRNA在损伤后表达上调,第2周达高峰后下降;NGF mRNA在损伤后表达上调,第3周达高峰值后下降.PMA侧PKC mRNA于第2、3和4周表达较对照侧明显增高,差异有统计学意义(P＜0.01或P＜0.05);NGF mRNA第2、3和4周表达也较对照侧明显增强,差异有统计学意义(P＜0.01).轴突数目在2、3和4周时多,差异有统计学意义(P＜0.01). 结论 PKC介导了周围神经损伤修复中的NGF mRNA表达及神经再生,而且PMA能够促进NGF mRNA表达及促进轴突生长.     

不同肠内营养液与生长激素联合应用对烫伤大鼠炎性反应的影响

目的 了解标准肠内营养(EN)、肠内免疫营养(EIN)液与重组人生长激素(rhGH)联合应用对烫伤大鼠炎性反应的影响. 方法 将128只SD大鼠按随机数字表法分为EN、EIN、EN+rhGH、EIN+rhGH组,每组32只.将大鼠制成总面积30%TBSA的Ⅲ度烫伤模型,分别于伤后1、4、7、10 d抽取各组大鼠静脉血,检测血清内毒素、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)水平;切取大鼠肝组织检测其CD14 mRNA、TNF-α mRNA的表达.另取8只SD大鼠作为对照组,检测上述指标. 结果 伤后各组各时相点大鼠血清内毒素、IL-6、TNF-α水平以及肝组织中的CD14 mRNA、TNF-α mRNA表达均高于对照组(P＜0.01).伤后4、7、10 d,EIN组和EN+rhGH组血清内毒素、IL-6、TNF-α水平以及肝组织CD14 mRNA、TNF-α mRNA表达均低于EN组(P＜0.05或P＜0.01);伤后10 d,EIN+rhGH组血清内毒素[(0.37±0.07)EU/mL]、IL-6[(289±49)ng/L]、TNF-d[(1.87±0.32)μg/L]水平以及肝组织CD14 mRNA(0.39±0.05)、TNF-α mRNA(0.47±0.03)表达均低于EIN组[(0.48±0.08)EU/mL、(364±53)ng/L、(2.50±0.48)μg/L、0.67±0.06、0.66±0.05,P＜0.05或P＜0.01]. 结论 EN、EIN液与rhGH联合应用可减轻大鼠烫伤后的炎性反应,且rhGH具有明显的协同作用.     

异氟烷对发育期大鼠海马IL-1β mRNA、IL-6 mRNA和TNF-α mRNA表达的影响

目的 探讨异氟烷对发育期大鼠海马IL-1β mRNA、IL-6 mRNA和TNF-α mRNA表达的影响.方法 出生7 d的SD大鼠64只,随机分为2组(n=32):对照组(C组)和异氟烷麻醉组(I组).I组大鼠吸入1.5%异氟烷麻醉6 h,C组吸入空气.I组于麻醉前(T0,基础状态)、麻醉2 h(T1)、4 h(T2)、6 h(T3)、麻醉停止后4 h(L)、6 h(T5)、12 h(T6)、24 h(T7)时,C组在对应时点各取4只大鼠,测定海马IL-1β mRNA、IL-6 mRNA及TNF-α mRNA的表达水平.结果 C组各时点海马IL-1β mRNA、IL-6 mRNA和TNF-α mRNA比较差异无统计学意义(P＞0.05);与C组比较,I组海马T1～5 时IL-1βmRNA表达上调,T2,3 时IL-6 mRNA表达上调,T1～6时TNF-α mRNA表达上调(P＜ 0.05).结论 1.5%异氟烷麻醉可短暂上调发育期大鼠海马IL-1β mRNA、IL-6 mRNA和TNF-α mRNA的表达.     

促红细胞生成素促进大鼠坐骨神经再生作用的实验研究

目的 探讨促红细胞生成素(Erythoropoietin,EPO)对大鼠坐骨神经损伤修复后神经再生的影响,为周围神经损伤的临床治疗提供实验依据.方法 雄性SD大鼠40只,随机分为两组,即EPO组和神经生长因子(NGF)组,用硅胶管桥接10 mm的坐骨神经缺损,EPO组和NGF组分别注射EPO和NGF.术后4周和8周时每组分别提取10只大鼠,以坐骨神经功能指数(SFI)、运动神经传导速度(MNCV)、形态学观察和蛋白基因产物9.5(PGP 9.5)免疫组织化学染色,评估EPO对大鼠坐骨神经再生的影响.结果 术后4周SFI,EPO组为[(-78.85±3.87),x-±s,下同],NGF组为(-79.98±4.58),差异无统计学意义(P>0.05);术后8周SFI,EPO组为(-60.26±2.91),NGF组为(-64.65±4.11),差异有统计学意义(P<0.05).术后4周和8周时,EPO组MNCV、有髓神经纤维数目以及PGP9.5免疫阳性神经纤维的平均光密度和积分光密度均优于NGF组,差异有统计学意义(P<0.05).结论 EPO 能促进大鼠坐骨神经损伤后的修复与再生.     

地塞米松对老龄大鼠术后认知功能的影响

目的 评价地塞米松对老龄大鼠术后认知功能的影响.方法 雄性SD大鼠180只,18 ～ 20月龄,体重400 ～ 600 g,采用随机数字表法,将大鼠随机分为3组(n=60)∶对照组(C组)、手术组(S组)和地塞米松组(D组).采用大鼠剖腹探查手术模型.D组于麻醉开始时腹腔注射地塞米松10 mg/kg.C组不进行手术,腹腔注射生理盐水2 ml/kg.于术后3h、7d时测定海马OX42(小胶质细胞激活特异性标志物)的表达水平；于术后3h、1d、3d和7d时测定海马IL-1β mRNA和TNF-α mRNA的表达水平.采用Morris水迷宫实验和条件恐怖适应实验检测大鼠术后认知功能.结果 与C组比较,S组和D组逃逸潜伏期延长,穿越原平台次数减少,术后僵直时间缩短,海马OX42表达、IL-1β mR-NA和TNF-α mRNA表达上调(P＜0.05或0.01)；与S组比较,D组逃逸潜伏期缩短,穿越原平台次数增多,术后僵直时间延长,海马OX42、IL-1β mRNA和TNF-α mRNA表达下调(P＜0.05或0.01).结论 地塞米松可抑制海马小胶质细胞过度激活,减轻炎性反应,从而改善老龄大鼠术后认知功能.     

脾切除术对大鼠海马tau表达的影响

目的 评价脾切除术对大鼠海马tau表达的影响.方法 SD大鼠105只,随机分为3组,正常对照组(A组,n=15)不给予任何处理,麻醉组(B组,n=45)仅吸入1.5%异氟醚2 h,手术+麻醉组(C组,n=45)吸入1.5%异氟醚(吸入2 h)麻醉下实施脾切除术.B组和C组分别于麻醉后或术后1、3、7 d时处死15只大鼠,取海马组织,测定海马IL-1β mRNA、TNF-α mRNA、IL-1β、TNF-α、总tau、苏氨酸第205位点磷酸化tau(pT205 tau)、丝氨酸第396位点磷酸化tau(pS396 tau)、总糖原合成酶-3β(GSK-3β)和磷酸化GSK-3β(p-GSK-3β)的表达水平.结果 与A组比较,B组各时点IL-1β mRNA、TNF-α mRNA、IL-1β、TNF-α、总tau、pT205 tau、pS396 tau、GSK-3β和p-GSK-3β的表达水平差异无统计学意义(P＞0.05),C组术后IL-1βmRNA、TNF-α mRNA、IL-1β、pT205 tau和pS396 tau的表达上调,p-GSK-3β表达下调(P＜0.05或0.01).结论 手术创伤可导致大鼠海马tau磷酸化,其机制与手术创伤诱发炎性反应,从而激活GSK-3β有关.     

急性胰腺炎肝损伤TNF-α mRNA及IL-6 mRNA的表达实验研究

目的 探讨急性胰腺炎(acute pancreatitis,AP)肝肿瘤坏死因子-α mRNA(tumor necrosis factor-α mRNA,TNF-α mRNA),白细胞介素-6 mRNA(interleukin-6 mRNA,IL-6 mRNA)的表达及肝脏损伤.方法 SD大鼠随机分为AP组和假手术组(sham operation,SO),分别于术后3,6,12 h取肝组织行光镜及电镜观察;检测血清丙氨酸氨基转移酶(alanine aminotransferase,ALT);放射免疫法(radio immunoassay,RIA)测定血清TNF-α,IL-6;实时定量聚合酶链反应(realtime polymerase chain reaction,Real-time PCR)检测肝组织TNF-α mRNA,IL-6 mRNA.结果 与SO组正常的肝组织、细胞形态对比,AP组出现肝损伤的病理形态变化;与SO组相比,AP组的血清ALT以及TNF-α,IL-6水平显著增高(P＜0.05);在AP发展的3～12 h内,肝TNF-α mRNA和IL-6 mRNA的表达明显增加,显著高于同一时段的SO组.结论 AP时肝TNF-α mRNA,IL-6 mRNA的表达与其肝脏损伤可能相关,提示肝TNF-α,IL-6对AP肝脏损伤发生和发展有重要作用.     

坐骨神经创伤性华勒氏变性中雪旺细胞凋亡初步研究

目的探讨成年大鼠坐骨神经创伤性华勒氏变性中雪旺细胞凋亡的存在及其时相性变化规律.方法利用成年雌性SD大鼠坐骨神经横断复制华勒氏变性模型.将74只SD大鼠随机分为12组.1个正常组(8只)、11个实验组(66只).每只实验组大鼠双后肢再随机分为试验肢(构成试验组)和对照肢(构成对照组).分别于术后1 h,6 h,12 h,24 h,2 d,3 d,4 d,8 d,14 d,21 d,30 d共11个时相点,切取坐骨神经中下段标本.检测各组神经纤维形态学改变,雪旺细胞S-100蛋白和凋亡基因相关产物Bcl-2、Fas、Bax表达水平变化,并用TUNEL法检测雪旺细胞凋亡指数.结果①试验组雪旺细胞数量术后24 h开始明显减少,术后8 d才开始重新增多.②S-100蛋白表达对照组变化无统计意义(P＞0.05),试验组则在术后1 h,21 d两个时间点变化有统计意义(P＜0.05).③雪旺细胞凋亡抑制基因产物Bcl-2表达,正常组双侧肢变化无差异(P＞0.05),而对照组术后6 h明显升高,术后24 h、4 d、21 d轻度增高(P＜0.01),试验组术后6 h,24 h,8 d,14 d,30 d进行性升高(P＜0.01).④雪旺细胞凋亡促进基因产物Bax表达,正常组双侧肢比较无差异(P＞0.05),而对照组术后6 h,3～21 d持续高表达(P＜0.01),试验组14 d开始进行性上升(P＜0.01).⑤雪旺细胞凋亡促进基因产物Fas表达,正常组双侧肢比较无差异(P＞0.05),对照组仅轻度增高(P＞0.05),而试验组术后12 h开始进行性升高(P＜0.01).⑥TUNEL法凋亡试剂盒原位检测显示正常组雪旺细胞凋亡发生率极低,双侧肢比较无差异(P＞0.05);试验组分别在术后6 h,24 h,2 d,21 d出现大量雪旺细胞凋亡阳性核(P＜0.01),高峰出现在华勒氏变性早期.结论成年大鼠坐骨神经横断后,远侧段创伤性华勒氏变性早期存在雪旺细胞凋亡高峰.并且雪旺细胞凋亡的发生,及凋亡相关促进基因Bax、Fas和抑制基因Bcl-2的表达均具有特定的时相性变化特点.     

大黄丹参对实验性重症急性胰腺炎大鼠肝胰组织TNF-a mRNA和IL-10 mRNA表达的影响

目的:观察中药大黄丹参治疗重症急性胰腺炎大鼠肝胰组织TNF-α mRNA和IL-10 mRNA表达的影响 .方法:SD大鼠30只,随机平均分成假手术组、重症急性胰腺炎对照组及大黄丹参治疗组.造模后6 h后用荧光PCR方法测定各组大鼠肝脏及胰腺组织TNF-α mRNA和IL-10 mRNA.结果:肝脏组织中,重症急性胰腺炎组大鼠TNF-α mRNA和IL-10 mRNA的表达均较假手术组有明显升高(P<0.05);中药治疗后TNF-α mRNA的表达下降(P<0.05),IL-10 mRNA的表达升高(P<0.05).胰腺组织中,重症急性胰腺炎组TNF-α mRNA和IL-10 mRNA表达同样升高(P<0.05),中药治疗后TNF-α mRNA的表达降低(P<0.05),但IL-10 mRNA表达与急性胰腺炎组比较无统计学差异.结论:SAP大鼠在肝脏和胰腺组织中,TNF-α mRNA和IL-10 mRNA均有明显升高,两者呈同一化的进程.大黄丹参治疗能够使肝胰组织的TNF-α mRNA表达下降,使肝IL-10 mRNA升高,显示了中药的调节作用.     

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.