两种去细胞人心脏瓣膜的免疫原性分析

目的应用组织工程学方法去除人同种心脏瓣膜(HV)的内皮细胞成分或全部细胞成分,比较两种去细胞HV的免疫原性变化。方法采用低渗液-去污剂(1%Triton)-核酸酶[1μg/ml核糖核酸酶(RNase)和10μg/ml去氧核糖核酸酶(DNase)]去细胞法去除HV表面的内皮细胞成分,保留间质细胞及细胞外基质结构的完整性;采用低渗液-去污剂(1%去氧胆酸)-核酸酶[20μg/ml RNase和200μg/ml DNase]去细胞法去除HV组织中所有细胞成分,保留完整的细胞外基质。免疫组织化学方法测定HLA-DR抗原在HV组织中的表达;行大鼠皮下移植试验,组织学评价及定性、定量分析组织的钙化程度。结果免疫组织化学结果证实HV去内皮细胞和去全部细胞后组织中HLA-DR抗原表达均下降,但去全部细胞HV的HLA-DR抗原表达下降更为显著。大鼠皮下移植实验结果表明深低温液氮保存HV和去内皮细胞HV组织中有大量炎性细胞浸润,以淋巴细胞为著,管壁组织更为显著;去全部细胞HV炎性反应较轻,仅组织边缘有少量炎性细胞浸润。钙盐染色深低温液氮保存HV和去内皮细胞HV组织中可见钙盐沉积,呈现大量黑色颗粒,管壁组织更为显著;而去全部细胞HV组织中钙盐沉积极少。原子吸收光谱法定量分析结果表明去全部细胞HV组织中钙离子含量明显低于去内皮细胞HV和深低温液氮保存HV(P0.05),后两者差异无统计学意义(P0.05)。结论去全部细胞HV组织免疫原性显著下降,移植后炎性反应和组织钙化程度显著减轻。去内皮细胞HV组织免疫原性及移植后炎性反应有所下降,但移植后组织钙化程度仍显著增高,且管壁组织钙盐含量增高较瓣叶组织更加显著,提示组织中大量的间质细胞可能是参与HV移植后免疫反应、导致HV移植后钙化毁损的主要组织成份。     

去细胞组织工程同种心脏瓣膜的生物学特征

目的　构建去细胞组织工程同种心脏瓣膜 ,对比研究同种心脏瓣膜去细胞前后的生物学特征。方法　取液氮保存的人同种主动脉带瓣管道 ,采用低渗液 -去污剂 ( 1%DOA) -核酸酶去细胞法 ,测定去细胞前后组织学、组织厚度、组织含水量、热皱缩温度、组织基因组DNA含量、胶原蛋白含量。结果　同种心脏瓣膜、管壁及肌肉组织中去除所有细胞成分 ,保留了完整的细胞外基质。与去细胞前相比 ,管壁组织的含水量 [( 75 4 4± 1 84 ) %对 ( 82 0 5± 0 71) % ,P <0 0 5 ]明显增加 ,组织基因组DNA含量显著下降(瓣叶下降 91 14 %、管壁下降 91 5 3% ) ;瓣叶组织含水量、组织厚度、热皱缩温度及组织胶原蛋白含量差别无显著性。结论　低渗液 -去污剂 ( 1%DOA) -核酸酶去细胞法方便有效 ,去细胞的同种组织工程心脏瓣膜生物学特性稳定 ,符合机体要求 ;且为受体细胞化组织工程心脏瓣膜的研制提供了可靠的天然纤维支架材料     

去细胞组织工程同种心脏瓣膜的生物力学研究

目的　观察去细胞组织工程同种心脏瓣膜的生物力学特性。方法　取液氮保存的人同种主动脉带瓣管道 ,采用低渗液 去污剂 (1%去氧胆酸 ) 核酸酶法去除了同种心脏瓣膜组织中所有的细胞成分 ,组织基因组DNA含量下降 91% ,保留了完整的细胞外基质。测定去细胞前后组织厚度、组织含水量、热皱缩温度、应力应变曲线、破坏强度及组织伸长比。结果　与去细胞前相比 ,只有管壁组织的含水量去细胞前与去细胞后比较明显增加 (P <0 .0 1) ,瓣叶组织含水量、组织厚度、热皱缩温度、应力应变曲线、破坏强度及组织伸长比差异无显著性 (P >0 .0 5 )。结论　去细胞组织工程同种心脏瓣膜的生物力学特性稳定 ,符合机体的要求 ,且为受体细胞化组织工程心脏瓣膜的研制提供了可靠的天然的纤维支架材料。     

转Endostatin基因角朊细胞移植对烧伤深Ⅱ°创面愈合及瘢痕增生的影响

目的探讨转内皮生长抑制素(ES)基因角朊细胞移植对烧伤深Ⅱ°创面愈合及瘢痕增生的影响。方法将人体皮肤移植于裸鼠并造成深Ⅱ°烧伤创面。实验分为对照组(11只)、单纯角朊细胞移植组及转ES基因角朊细胞移植组(各10只)。对照组不行细胞移植,创面自行愈合;单纯角朊细胞移植组创面移植培养人角朊细胞;转基因移植组移植转ES基因角朊细胞。观察各组裸鼠创面愈合特点、瘢痕增生情况,并对愈合区组织进行病理切片检查、检测愈合区皮肤组织ES 蛋白表达、I、Ⅲ型前胶原含量。结果转基因移植组裸鼠创面愈合时间(13±5)d与单纯移植组 (14±5)d差异无统计学意义(P>0．05),但明显短于对照组[(25±7)d,P<0．01]。对照组裸鼠创面愈合后瘢痕增生明显,伤后100 d厚度≥0．22 cm,单纯移植组瘢痕增生厚度≥0．17 cm,转基因移植组仅有轻度瘢痕增生,愈合区皮肤组织ES蛋白检测阳性。单纯移植组、转基因移植组愈合区组织前胶原I含量(65．3±8．5)μg／g,(61．4±7．0)μg／g、前胶原I／前胶原Ⅲ比例(0．66±0．15,0．57± 0．13)明显低于对照组(1．51±0．37,P<0．01),而前胶原Ⅲ含量显著高于对照组(P<0．01)。结论转ES基因移植既可加速创面封闭,又能抑制愈合后瘢痕形成。     

生物材料-牛颈静脉带瓣管道化学改性的实验研究

目的探讨醇类改性牛颈静脉带瓣管道的抗钙化效果及可能机制。方法用戊二醛鞣制的牛颈静脉分别用乙醇和丁二醇保存60d,植入大白鼠背部皮下90d取出试片,管壁和瓣膜分别做光镜、电镜观察及钙含量测定。结果两组试片组织结构保存基本完好;两组管壁平均钙含量为:乙醇(172.79±61.38)μg/mg,丁二醇(180.67±29.17)μg/mg(P<0.05);瓣膜钙含量为:乙醇(2.13±0.85)μg/mg,丁二醇(1.73±1.20)μg/mg(P<0.05);每组内管壁钙含量比瓣膜均显蓍增高(P<0.01)。结论两种醇类均可做为牛颈静脉生物组织材料的一种的改性试剂;牛颈静脉材料的钙化过程与组织材料的致密度有关。     

经液氮保存同种带支架瓣膜的制备

目的探讨经液氮保存的同种带支架瓣膜的制作方法。方法将制作完成的瓣架经液氮保存1个月后复温,进行几何形态检测(6枚)。涤纶包布及缝线经液氮保存1~3个月后复温,检测机械强度变化(6例)。采集同种带瓣主动脉和肺动脉,缝于瓣架上,缝制完成后打水观察瓣叶的闭合情况,初步粗略估算Rb/Rc、H/Rc和α值。将制作完成的瓣膜灭菌培养后,程控降温,液氮保存。结果瓣架直径在液氮冷冻前为(21·1±0·06)mm,冷冻后为(21·1±0·05)mm,P>0·05;瓣架高度冷冻前为(14·03±0·02)mm,冷冻1个月后为(14·04±0·03)mm,P>0·05;几何形态未发生明显变化。涤纶包布经液氮冷冻前纤维方向拉力强度纵向为(19·05±1·64)MPa,冷冻1个月、3个月后分别为(17·29±1·79)MPa、(18·23±1·6)MPa(P>0·05);横向纤维冷冻前为(18·16±1·16)MPa,冷冻后分别为(16·81±0·97)MPa、(17·46±1·54)MPa(P>0·05);包布物理强度未发生明显变化。缝线经液氮冷冻前拉力强度为(163·99±7·83)MPa,冷冻1个月、3个月后分别为(168·88±6·28)MPa、(168·74±1·85)MPa,P>0·05;缝线物理强度未发生明显变化。初步估算Rb/Rc值为1·2左右,H/Rc值为1·4左右,α值为10°左右,瓣架构型均符合制作标准。结论经液氮保存同种带支架瓣膜的材料选择、设计和制作方法均达到了人工瓣膜的技术要求。     

促进组织工程心脏瓣膜细胞黏附力的初步研究

目的探讨纤维连接蛋白(Fn)增强种子细胞与组织工程心脏瓣膜(TEHV)黏附力的可行性,为组织工程心脏瓣膜的构建提供良好的细胞基础。方法取6个规格相同的有P4HB[聚β羟基丁酯]构建的心脏瓣膜,气体消毒后分别置入12孔板中,每2个为1组,前两组分别被Fn及多聚赖氨酸(poly-lysine)包被,第3组空白对照。24 h后分别种植骨髓基质干细胞0．8×10~5个,24h后在瓣膜背面再分别种植0．25×10~5个。2周后分别行MTT检测及扫描电镜检测；取不同数量的MSC,行MTT检测,制作不同细胞个数与MTT吸收光度的曲线。结果经Fn包被的MTT吸光度A值(0．128 96±0．004 896)及poly-lysine包被的MTT吸光度A值(0．12033±0．03991)均明显高于对照组(0．11254±0．006556),P＜0．05,Fn组与poly-lysine组比较有统计学意义,前者高于后者。结论Fn能有效的促进细胞在生物可降解的组织工程心脏瓣膜的黏附及增殖,是发展组织工程心脏瓣膜的一种优良的促细胞黏附剂。     

海藻糖在同种瓣低温保存中的保护作用

目的探讨非渗透性低温保护剂海藻糖联合应用二甲基亚砜，用于同种瓣的深低温储存，并与常规应用的二甲基亚砜的冻存效果进行比较。方法分别以10％二甲基亚砜＋0．1mol／L海藻糖（实验组）和10％二甲基亚砜（对照组）作为冷冻保护剂，经程控梯度降温，液氮冻存大鼠的同种瓣6个月后复温，电镜、光镜观察、内皮细胞活力及葡萄糖代谢率测定，比较同种瓣的组织活性、代谢功能和结构变化。结果实验组的葡萄糖代谢率为（20．570±1．789）晷／L·d^-1明显高于对照组（18．621±1．842）g／L·d^-1（P〈0．01），内皮细胞活力（77．75±6．60）％也明显高于对照组（69．81±4．40）％（P〈0．01），并且其结构的破坏也较对照组轻（P〈0．05）。结论10％二甲基亚砜＋0．1mol／L海藻糖作为同种瓣的冷冻保护剂，其保护效果明显优于10％二甲基亚砜。     

表皮生长因子对大鼠移植小肠黏膜结构的保护作用

目的探讨表皮生长因子(EGF)对大鼠移植小肠黏膜结构的保护作用。方法近交系Wistar(RT1k)大鼠行异位全小肠移植后第2天开始给予完全胃肠外营养(TPN)至第10天,对照组(10只)行常规TPN支持,EGF组(10只)行常规TPN支持的同时加用重组人(rh)EGF 200μg·kg~(-1)·d~(-1),观察移植小肠黏膜的形态学变化(参数：绒毛高度、绒毛宽度、隐窝深度、黏膜厚度及绒毛表面积)和肠上皮细胞超微结构变化及肠黏膜蛋白质和DNA含量改变。结果移植前,肠黏膜形态学参数变化两组间差异无统计学意义(P＞0．05)。移植并TPN后,对照组各项参数明显低于移植前(P＜0．05),而EGF组各参数与移植前比较变化不明显(P＞0．05)。EGF组移植肠绒毛高度为(284．47±31．58)μm,绒毛宽度为(99．37±11．57)μm,隐窝深度为(98．78±10．83)μm,黏膜厚度为(389．56±31．72)μm,绒毛表面积为(0．089±0．009)mm~2；明显高于对照组的(176．45±14．62)μm、(74．2±16．85)μm、(74．45±8．34)μm、(259．38±24．65)μm和(0．041±0．005)mm~2,P均＜0．01。EGF组移植肠黏膜蛋白质含量[(84．65±8．32)mg/g wet wt]也明显高于对照组的[(53．73±11．45)mg/g wet wt,(P＜0．05)]而与基准值[(92．64±10．52)mg/g wet wt]接近；DNA含量[(0．86±0．10)mg/g wet wt]也显著高于对照组[(0．51±0．06)mg/g wet wt,(P＜0．01)]。EGF组移植肠上皮细胞超微结构基本保持完好,而对照组则出现明显线粒体肿胀,嵴短小紊乱和微绒毛萎缩。结论EGF能较好保护大鼠移植小肠黏膜结构,维持移植肠上皮细胞超微结构的完整。     

血管紧张素转换酶抑制剂对心脏移植后冠状血管增殖病变的影响

目的通过建立大鼠心脏移植后冠状血管增殖病变的模型,观察血管紧张素转换酶抑制剂(ACEI)对心脏移植后冠状血管增殖病变的影响。方法设立对照组、结扎组、ACEI+结扎组,观察2周后各组大鼠血液、心肌AngⅡ含量,心肌AngⅡ受体密度,及血管病理学结果。结果各组血液AngⅡ含量差异无统计学意义,结扎组心肌AngⅡ含量明显增高(17．42±5．49)fmol／mg．蛋白P<0．001比对照组,ACEI+结扎组AngⅡ含量明显下降(5．35±1．95)fmol／mg。蛋白P< 0．01比结扎组,结扎组AngⅡ受体密度增高(48．80±4．32)fmol／mg蛋白P<0．01比对照组,ACEI +结扎组内膜增生比结扎组明显减轻[内膜厚度(21．01±4．55)μm比(60．34±9．32)μm,P< 0．01)。结论心脏局部肾素-血管紧张素系统,AngⅡ及AngⅡ受体参与移植后冠状血管病变,A- CEI明显抑制移植后冠状血管病增殖变。     

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.