微囊化异种甲状旁腺组织移植的研究

目的探讨微囊化异种甲状旁腺(PTG)组织移植对Wistar大鼠甲状旁腺功能低下的治疗作用及微囊的通透性。方法 40只去甲状旁腺Wistar大鼠随机分为微囊组、非微囊组、空囊组、空白对照组。用海藻酸-钡交联微囊包裹兔甲状旁腺组织,移植至Wistar大鼠肾包囊。移植后每隔2周取血测血钙,移植后第16周取移植物进行透射电镜检查及T淋巴细胞、大鼠IgG抗体的免疫组织化学染色。结果微囊组移植后第4周血清钙由(1．62±0．04)mmol／L恢复至正常水平 (2．2～2．6)mmol／L,9例维持至观察期结束(P<0．01),非微囊组、空囊组及空白对照组血清钙差异无统计学意义(P>0．05)。第16周取出移植物检测显示移植物活性良好,微囊周围可见较多T 淋巴细胞浸润,囊壁及囊内IgG抗体染色阳性。结论海藻酸-钡交联微囊可对甲状旁腺组织起到有效的保护作用,使甲状旁腺组织较长时间存活并发挥正常功能。但海藻酸-钡交联微囊并未减轻受体免疫排斥反应的激活且未有效的免疫隔离IgG抗体。     

海藻酸-壳聚糖-聚乙烯乙二醇微囊生物相容性的研究

目的比较海藻酸-壳聚糖-聚乙烯乙二醇微囊(ACP微囊)和海藻酸-聚赖氨酸-海藻酸微囊(APA微囊)的生物相容性。方法(1)两种微囊(50、100和200个)与健康人血清共浴,检测微囊对补体的激活程度。(2)1000个APA和ACP微囊分别植入Wistar大鼠的腹腔,4d和3周时统计取出的微囊数和微囊的纤维化率。(3)Wistar大鼠胰岛用ACP微囊和APA微囊包裹,分别贯续置于含3.3mmol/L和16.7mmol/L葡萄糖的Hank's溶液中培养,测定培养液中胰岛素的浓度。结果(1)ACP微囊组残余补体活性高于APA微囊组。(2)4d时,ACP和APA微囊的取出数分别是845.0±40.4和807.6±45.7(P>0.05),囊周纤维化率分别是16.40%和65.68%(P<0.05);3周时两种微囊的取出数分别为715.0±133.0和367.5±105.6(P<0.05),囊周纤维化率为27.8%和83.9%(P<0.05)。(3)在含3.3mmol/L葡萄糖的Hank's液中,未微囊胰岛组、APA和ACP微囊化胰岛组的胰岛素浓度分别是(123.48±4.70)mIU/L、(110.11±12.18)mIU/L和(110.90±11.95)mIU/L,当葡萄糖浓度为16.7mmol/L时,胰岛素浓度分别是(754.75±13.81)mIU/L、(689.30±27.71)mIU/L和(684.28±70.10)mIU/L。结论海藻酸-壳聚糖-聚乙烯乙二醇微囊的生物相容性要优于海藻酸-聚赖氨酸-海藻酸微囊,前者更适合应用于微囊化胰岛移植。     

BPA微囊与APA微囊机械强度和生物相容性的比较研究

目的 比较海藻酸钡-多聚赖氨酸-海藻酸(BPA)微囊与海藻酸-多聚赖氨酸-海藻酸(APA)微囊的生物相容性和机械强度的生物物理特性.方法 用静电微囊发生仪制备BPA和APA微囊,通过机械振荡法和肌肉下移植来检测微囊的机械强度.通过微囊大鼠腹腔移植来观察BPA和APA微囊的生物相容性.结果 机械振荡48h后APA微囊的破损率为4.3%,BPA微囊仅为1.5%;肌肉下移植1个月后,组织切片H&E染色显示,APA和BPA微囊均保持完整,仅有轻度纤维化包裹;腹腔移植4、8和10周后,从大鼠腹腔内取出的微囊中95%～98%为结构完整,呈圆形,表面光滑,光镜下无明显的结缔组织包绕.结论 所制备的BPA微囊的生物相容性河机械强度优于APA微囊.     

海藻酸-壳聚糖-聚乙烯乙二醇微囊化异种胰岛移植治疗小鼠糖尿病

目的比较海藻酸-聚赖氨酸-海藻酸微囊化(APA)大鼠胰岛和海藻酸-壳聚糖-聚乙烯乙二醇微囊化(ACP)大鼠胰岛移植对小鼠糖尿病的治疗作用.方法链脲霉素220 mg/kg体重腹腔内注射制作小鼠糖尿病动物模型.成模后分成APA微囊组、ACP微囊组和未微囊化胰岛组,每只小鼠腹腔内分别植入200个相应胰岛,检测监测移植前后小鼠的血糖.结果移植后第1天,3组小鼠血糖均较移植前明显降低.未微囊化胰岛移植组小鼠术后第2天血糖均恢复到术前水平;APA微囊组和ACP微囊组小鼠血糖分别维持正常(57.00±14.61)d和(41.67±16.73)d,此两组间差异无显著性(P＞0.05),但均较未微囊化胰岛移植组明显延长(P＜0.05).结论 ACP微囊与APA微囊一样具有免疫隔离作用;ACP微囊化异种胰岛移植可纠正小鼠糖尿病.     

HOE 077对胰岛细胞微囊外纤维化反应及其活力的影响

目的　研究抗肝纤维化药物HOE 0 77对胰岛微囊外纤维化反应及细胞活力的影响。方法　猪胰岛分离后包裹在海藻酸钡微囊内 ,移植于Balb/c小鼠肝内。术后HOE 0 77通过溶解于饮用水中给药 ,对照组饮水中不含HOE 0 77。 1个月后处死动物 ,病理检查观察包囊外的纤维化反应程度 ,评价囊内细胞的存活情况。结果　对照组显示了明显的纤维化反应 ,纤维包裹层厚度平均为(6 2 .12± 3.84) μm ,细胞活力为 (15 .16± 2 .32 ) % ;而HOE 0 77治疗组纤维包裹厚度为 (4 1.44±2 .45 ) μm ,活力为 (2 3 .0 8± 2 .45 ) %。统计学分析表明 ,两组在囊外纤维包裹层的厚度及细胞活力上差异均有显著性 (P <0 .0 0 0 1和P <0 .0 1)。结论　抗肝纤维化药物HOE 0 77的应用为减轻微包囊的纤维化反应提供了一个新的途径     

海藻酸钠纯度对微囊化肝细胞腹腔移植中微囊纤维化的影响

目的　研究海藻酸钠纯度对微囊纤维化的影响。　方法　采用逐步过滤和氯仿 /丁醇萃取的方法纯化海藻酸钠 ,用纯化和未纯化的海藻酸钠制作两种微囊化肝细胞分别给两组大鼠 (各2 0只 )腹腔移植 ,观察不同时期微囊的回收率、微囊纤维化、囊内肝细胞的功能和结构。用3 H TdR掺入法测定纯度对淋巴细胞转化率的影响。　结果　纯化组的微囊回收率较未纯化组明显增高 (P <0 0 1)。纯化组移植 1个月后大部分肝细胞形态及酶组化染色正常。未纯化组移植后 1个月内肝细胞破坏。移植 6个月时 ,纯化组微囊仍保持完整光滑 ;而未纯化组移植 1个月后微囊全部纤维化。纯化的海藻酸钠对人类淋巴细胞转化率明显低于未纯化组。　结论　纯化的海藻酸钠能明显降低微囊的纤维化程度     

微囊化大鼠肝细胞移植的组织学研究

目的 研究微囊化大鼠肝细胞腹腔移植后的存活情况以及组织学改变。方法 用二步法胶原酶门－腔静脉灌注法分离Wistar大鼠肝细胞,用Percoll梯度分离液纯化,海酸钠－氯化钡法微囊化包裹肝细胞,分别行腹腔注射移植,将纯化的肝细胞移植至SD大鼠体内（第1组）、微囊化包裹的肝细胞移植至SD大鼠体内（第2组）及Wistar大鼠体内（第3组）,观察移植后各组不同时间肝细胞存活率及其组织学变化。结果 （1）移植后第4、7d,各组间肝细胞存活率的差异均有显著性（P＜0.01）;移植后第14d,第2组与经3组间肝细胞存活率的差异无显著性;（2）移植后第4d开始,微囊周围出现纤维增生现象,第2组较第3组明显。结论 微囊化可为移植的肝细胞提供免疫屏蔽作用,从而提高肝细胞移植的存活率;微囊周围纤维增生可影响肝细胞的存活率。     

共微囊化异种肝细胞胰岛联合移植治疗急性肝衰

目的　探讨共微囊化异种肝细胞胰岛联合移植对急性肝衰的治疗作用。方法　D 氨基半乳糖诱导小鼠急性肝衰 ;Seglen法分离大鼠肝细胞 ;Sutton法分离胰岛 ;自制双喷头成囊器制备微囊。比较生理盐水、自由肝细胞移植、微囊化肝细胞移植、共微囊化肝细胞胰岛联合移植 4组间存活率、体重、谷丙转氨酶、血清白蛋白、总胆红素、血糖等指标的变化情况。结果　共微囊化肝细胞胰岛联合移植组存活率达 10 0 % ,组间差异有显著性 (P <0 .0 5 ) ,各项生化指标也明显占优。肝细胞与胰岛 β细胞可在微囊内融合。 结论　共微囊化肝细胞胰岛联合移植对氨基半乳糖诱导的急性肝衰有最佳的治疗作用     

微囊化基因修饰细胞复合组织工程真皮构建及其对创面愈合的影响

目的探讨微囊化神经生长因子(nerve grow th factor,NGF)基因修饰的N IH 3T 3细胞复合组织工程真皮的可行性及其对急性创面愈合的影响。方法构建分泌型NGF真核表达质粒pcDNA 3.1+/NGF并导入N IH 3T 3细胞,筛选出稳定表达的细胞株,将此细胞包入海藻酸钠-多聚赖氨酸-海藻酸钠微囊中培养。以Ⅰ、Ⅲ型胶原为基质、人成纤维细胞和制备好的微囊为种子细胞,用组织工程皮肤培养系统构建复合微囊的组织工程真皮,体外培养1周后行羟脯氨酸(hydroxypro line,Hyp)测定,EL ISA法测定其分泌功能,组织形态学观察。以猪背部急性全层创面为模型,按移植物不同分为5组:NGF-N IH 3T 3微囊真皮组(A组)、N IH 3T 3微囊真皮组(B组)、空囊真皮组(C组)、NGF(5 ng/m l)+胶原膜组(D组)和空白对照组(E组),观察创面再上皮化及愈合速度和愈合时间。结果转NGF基因微囊复合组织工程真皮后体外培养6周,仍稳定分泌NGF(124.32 pg/m l),体外培养1周后,组织工程真皮中NGF-N IH 3T 3微囊组Hyp含量为69.68±6.20 m g/g,较空白对照组增加约2倍以上。移植治疗急性创面,A组平均愈合时间为25±2 d,B组为34±3 d,C组为34±2 d,D组为33±2 d,E组为40±3 d,A组创面愈合时间平均至少缩短约10 d,提高了创面愈合的速度。结论将分泌NGF微囊复合组织工程真皮后可提高组织工程真皮的质量,并促进急性创面的愈合。     

微囊化猪肝细胞移植治疗大鼠急性肝衰竭

目的探讨微囊化猪肝细胞移植(HTx)治疗大鼠急性肝衰竭(ALF)的效果。方法采用原位胶原酶循环肝灌注法分离中国实验用小型猪肝细胞,海藻酸钠-氯化钡法微囊化。应用 D-氨基半乳糖(D-gal)1．2 g／kg体重腹腔内注射制作SD大鼠ALF模型。ALF大鼠随机分为3组。注药24 h后分别将PRMI 1640培养液2 ml腹腔注射为对照(I组)、2 ml游离猪肝细胞(2×107个／ml)腹腔内移植(Ⅱ组),以2 ml微囊化猪肝细胞腹腔内移植(2×107个／ml,Ⅲ组)。观察移植后大鼠14 d存活率、谷丙转氨酶(ALT)、总胆红素(TB)、血氨(NH3)的改变和肝脏的病理变化。结果肝细胞移植后大鼠14 d存活率:I组为20．0％(5／25),Ⅱ组为66．7％(16／24),Ⅲ组为76．0％(19／ 25),3组间差异有统计学意义(P<0．05)。移植后第1天I组ALT、TB和移植前相比差异无统计学意义,Ⅱ、Ⅲ组ALT、TB下降。第4天3组ALT、TB均继续下降,Ⅱ、Ⅲ组低于I组(P<0．05), Ⅱ、Ⅲ两组间差异无统计学意义(P>0．05)。移植后第7天,ALT进一步下降,3组间差异有统计学意义(P<0．05);TBⅢ组显著低于Ⅱ组和I组(P<0．05),Ⅱ组低于I组但差异无统计学意义 (P>0．05)。移植后第14天,肝功能均明显恢复,ALT、TBⅡ、Ⅲ组均低于I组(P<0．05),Ⅱ、Ⅲ两组间差异无统计学意义(P>0．05)。各组治疗前后NH3有所改善,但各时间段及各组之间差异无统计学意义(P>0．05)。微囊组和游离肝细胞组移植后肝脏病理损害修复较快,而阴性对照组肝脏再生修复较差。结论微囊化猪肝细胞腹腔内移植可以提高药物诱导急性肝衰竭大鼠的存活率,改善急性肝衰竭大鼠的肝功能,有利于受体受损肝脏的再生修复,但对降低血氮的效果不明显。     

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.