金属蛋白酶组织抑制剂1在大鼠肾小管间质损害中的表达及其意义

目的 观察单侧输尿管梗阻(UUO)大鼠模型中金属蛋白酶组织抑制剂1(TIMP-1)在肾小管间质中的表达部位、动态变化及其与肾小管问质损害的关系。方法 制备UUO大鼠模型,采用免疫组织化学方法检测UUO术后第1、3、5、7、14天肾小管间质中TIMP-1、α-平滑肌肌动蛋白(SMA)、增殖细胞核抗原(PCNA)和单核巨噬细胞抗原(ED)-1的表达及其与输尿管梗阻后肾小管间质损害的关系。结果 UUO术后第1天肾间质可见少量TIMP-1表达细胞,第3～7天TIMP-1表达明显增加,主要表达于肾小管上皮细胞和肾间质。UUO术后第3天肾小管PCNA表达达高峰,随后下降,而肾间质PCNA水平于第7～14天仍较高。UUO术后第3天肾间质成纤维细胞及肾小管上皮细胞可检出α-SMA表达并随时间递增。α-SMA阳性面积与肾间质相对面积成正相关(r=0.924,p<0.01)。TIMP-1表达与间质相对面积(r=0.835,P<0.05)及α-SMA阳性面积(r=0.922,P<0.01)成正相关。结论 TIMP-1蛋白质于肾小管间质病变早期表达于肾小管间质,早于肾间质纤维化出现,其表达量与肾间质α-SMA表达及肾间质相对面积呈正相关并随病变进展逐渐增加。TIMP-1在肾小管上皮细胞和问质细胞的高表达及肾小管上皮细胞和间质细胞增殖可能参与介导UUO术后肾小管间质损害。     

补肾排毒合剂对单侧输尿管梗阻大鼠肾间质MMP-9与TIMP-1基因表达的影响

目的：研究单侧输尿管梗阻（unilateral ureteral obstruction，UUO）后大鼠肾间质MMP-9、TIMP-1基因的表达变化，探讨补肾排毒合剂对肾间质纤维化的保护作用。方法：采用UUO诱导肾间质纤维化的动物模型，将大鼠随机分为假手术组（Sham组）、模型组（UUO组）和补肾排毒合剂治疗组（REM组），用RT—PCR技术检测肾组织在术后3、10、20、30d MMP-9、TIMP-1的基因表达。结果：UUO组TIMP-1 mRNA的表达明显高于Sham组（P〈0．01），REM组TIMP-1 mRNA表达均明显低于UUO组（P〈0、01）。MMP-9 mRNA在UUO术后明显升高，第10天达到高峰，继之下降。REM组10d后下降幅度较小，在20、30d时间点高于UUO组（P〈0，01）。结论：补肾排毒合剂影响MMP-9／TIMP-1的基因表达，从而促进了ECM的降解过程，延缓肾间质纤维化的进展。     

绞股蓝总皂苷防治单侧输尿管结扎大鼠肾间质纤维化的实验研究

目的探讨绞股蓝总皂苷(GPs)对单侧输尿管结扎(UUO)大鼠肾组织结缔组织生长因子(CTGF)表达及肾间质纤维化的影响。方法采用UUO大鼠模型,将大鼠随机分为3组假手术组、模型组、GPs组。假手术组和模型组仅给予标准饲料30g,GPs组于术前3d至术后9d每天给予GPs200mg·kg-1·d-1灌胃,第9d处死各组大鼠。免疫组化法检测各组肾组织CTGF、转换生长因子β1(TGF-β1)和α-平滑肌肌动蛋白(α-SMA)的表达;RT-PCR方法检测各组CTGFmRNA含量;Masson染色评定各组肾小管间质损害程度。结果模型组CTGF、TGF-β1、α-SMA的表达及肾小管间质损伤指数明显高于假手术组(P<0.01),而GPs组各项指标明显低于模型组(P<0.01)。各项指标作相关分析,CTGF与肾小管间质损伤指数(r=0.788,P<0.01)、TGF-β1(r=0.879,P<0.01)、α-SMA(r=0.940,P<0.01)为正相关关系。结论绞股蓝总皂苷可以抑制肾纤维化时结缔组织生长因子表达,从而遏制肾纤维化的进展。     

人基质金属蛋白酶1组织抑制剂转基因小鼠肾小管间质炎症的改变

目的观察基质金属蛋白酶1组织抑制剂(TIMP-1)过表达对肾小管间质炎症反应的影响。方法采用人TIMP-1转基因小鼠和野生型小鼠(n=8)构建单侧输尿管梗阻(UUO)模型。以3 d和14 d为时间点,Masson染色观察肾组织形态学变化,间接免疫荧光法观察肾组织内F4／80阳性细胞的表达;Western印迹检测TIMP-1、TIMP-2、MMP-2、MMP-9和ICAM-1的蛋白表达,明胶酶谱法检测MMP-2和MMP-9的活性,反向酶谱法检测TIMP-1的活性。结果UUO术后肾小管间质病理损伤加重[肾间质纤维化面积(46．24±6．58)％比野生型(36．33±5．12)％．P< 0．05],F4／80阳性细胞数目增加[(68．9±15．6)个／视野比野生型(52．4±13．3)个／视野,P< 0．05],ICAM-1蛋白表达显著上调,术后14 d上述改变在转基因组中更为显著(P<0．05)。UUO术后TIMP-1蛋白表达及活性上调,在术后14 d达高峰,在转基因组中增加更为显著(P< 0．05)。MMP-2和MMP-9的蛋白表达及活性在术后逐渐下降,UUO术后14 d转基因组降低更为显著(P<0．05)。结论TIMP-1过表达可通过增强炎症加重肾小管间质损伤。     

黄芪对肾间质纤维化模型大鼠肾组织MMP-9／TIMP-1表达的影响

目的探讨基质金属蛋白酶9（MMP-9）和金属蛋白酶组织抑制剂1（TIMP-1）在肾间质纤维化中的表达及黄芪抗纤维化的分子作用机制。方法采用单侧输尿管结扎（UUO组）造模。将24只SD大鼠随机分为假手术组（Sham组）、模型组（UUO组）、厄贝沙坦治疗组（Irbesartan组）和黄芪治疗组（AM组）4组,每组6只。造模14d后抽血检测肾功能,取结扎侧肾组织观察肾间质病变,免疫组织化学染色法检测肾组织MMP-9和TIMP-1表达。结果①AM组血肌酐和尿素氮水平较UUO组低（P〈0．05）,肾纤维化程度较UUO组有明显改善（P〈0．01）。②肾组织TIMP-1表达,UUO组较Sham组显著升高（P〈0．01）,AM组较UUO组明显降低（P〈0．01）;肾组织MMP-9表达,UUO组与Sham组差异无统计学意义（P〉0．05）,AM组较UUO组显著升高（P〈0．01）。结论黄芪可改善UUO大鼠肾功能,并可通过抑制TIMP-1表达,调节MMP-9／TIMP-1平衡来发挥其抗纤维化的作用。     

氟伐他汀对UUO大鼠肾间质单核细胞趋化蛋白-1表达及巨噬细胞浸润的影响

目的观察氟伐他汀对单侧输尿管梗阻大鼠肾间质单核细胞趋化蛋白-1(MCP-1)表达和巨噬细胞浸润的影响,探讨其抗纤维化机制。方法90只SD雌性大鼠随机分成假手术(SOR)组、单侧输尿管梗阻术(UUO)模型组和UUO+氟伐他汀治疗组(T-UUO,氟伐他汀20mg·kg-1·d-1)。于术后第1、4、7、10、14d分别处死各组大鼠。用HE及Masson染色动态观察肾脏病理变化,免疫组织化学法测定MCP-1、单核巨噬细胞抗原(ED-1)的表达。结果UUO模型组肾小管-间质MCP-1与ED-1表达较SOR组增加(P<0.05);在术后各时间点,T-UUO组大鼠肾小管-间质MCP-1、ED-1的表达及肾间质胶原相对面积较UUO模型组显著减少,但/仍高于SOR组(P<0.05)。结论氟伐他汀可通过降低MCP-1表达、减少单核/巨噬细胞浸润以抑制肾间质纤维化。     

阿托伐他汀对单侧输尿管梗阻大鼠肾间质中TGF-β1及TIMP-1表达的影响

目的:研究单侧输尿管梗阻(UUO)后转化生长因子-β1(TGF-β1)、组织金属蛋白酶抑制因子-1(TIMP-1)的表达变化,从而探讨肾间质纤维化的发生机制及阿托伐他汀的保护作用.方法:将45只大鼠随机分为假手术组、模型组和阿托伐他汀组(简称治疗组).采用UUO模型,在术后5 d 、10 d、15 d每组各取5只处死,留取空腹血清检测血脂浓度和肾功能,左肾组织行HE和Masson染色,动态观察肾脏病理学变化,并用免疫组化方法测定肾组织中TGF-β1、TIMP-1的表达变化.结果:各组大鼠血脂浓度无统计学差异.模型组大鼠肾间质中TGF-β1、TIMP-1的表达随梗阻时间的延长逐渐增多,与假手术组相比有统计学差异 (P<0.001).治疗组与模型组相比,各时间点TGF-β1、TIMP-1的表达下调有统计学差异(P<0.001),且两者之间存在一定的相关性(r=0.37,P< 0.01). 结论:阿托伐他汀可能通过阻断肾组织中TGF-β1的作用和抑制TIMP-1的过度表达而发挥其肾保护作用,这一作用与其降血脂作用无关.     

黄葵胶囊对单侧输尿管梗阻大鼠肾间质纤维化的保护作用

目的：采用单侧输尿管梗阻（UUO）致肾间质纤维化大鼠模型,观察黄葵对肾脏转化生长因子β激活激酶（TAK1）表达的影响。方法：96只大鼠随机分为假手术组、模型组（UUO组）、黄葵治疗组及缬沙坦治疗组,术后7、14、21 d各组分别处死8只大鼠,HE及Masson染色观察UUO大鼠梗阻侧肾脏病理变化,原位杂交、RT-PCR及Western-bloting检测肾组织TAK1的表达。结果：在UUO术后第7天梗阻侧肾脏出现明显的间质纤维化,并随着时间的进展而明显;在不同时限内模型组及治疗组TAK1表达较假手术组比较均增高（P〈0.01）,经黄葵干预后,梗阻侧肾组织间质纤维化程度有所减轻,且TAK1表达明显减少（P〈0.01）。结论：黄葵可能通过下调TAK1表达,从而减轻间质纤维化的病程进展。     

三七总皂苷对单侧输尿管梗阻大鼠肾组织BMP-7及TGF-β1/samds信号传导通路的影响

目的:观察三七总皂苷(PNS)对单侧输尿管梗阻(UUO)大鼠肾组织骨形成蛋白-7(BMP-7)及TGF-β1/Smads信号传导通路的影响。方法:将50只雄性Wistar大鼠随机分为5组:假手术组、模型组、肾康注射液组(对照组)、PNS低剂量组(低剂量组)、PNS高剂量组(高剂量组),每组10只,除假手术组,其余各组用UUO法建立肾间质纤维化动物模型,术前1d起各组给予相应浓度和剂量的药物,术后第14天处死所有大鼠,检测大鼠血肌酐(Scr)和尿素氮(BUN)变化,梗阻侧肾组织行HE染色、PAS染色和Masson染色,观察肾组织病理变化并半定量计算肾小管损伤指数(TII),免疫组化法检测BMP-7、TGF-β1、Smad2、Smad7在肾组织的表达。结果:与模型组相比,PNS和肾康注射液能明显降低UUO大鼠术后14dScr、BUN(P<0.05);对梗阻侧肾组织HE染色、PAS染色进行TII评分发现,2个试验组大鼠肾小管损伤指数显著低于模型组(P<0.01);Masson染色观察发现,2个实验组大鼠肾小管间质病变明显轻于模型组;免疫组化法染色并对其灰度值测定发现,与模型组相比,2个试验组大鼠TGF-β1、Smad2在肾组织的表达下调(P<0.01),BMP-7、Smad7在肾脏组织的表达上调(P<0.01)。结论:PNS可能通过干预BMP-7/Smads/TGF-β1信号转导通路抑制了TGF-β1信号的细胞内转导,而起到抗肾间质纤维化的作用。     

槲皮素对单侧输尿管梗阻大鼠肾脏α-平滑肌肌动蛋白表达的影响

目的:观察槲皮素(Que)对单侧输尿管梗阻大鼠肾脏病理和α-平滑肌肌动蛋白(α-SMA)表达的影响,探讨槲皮素对肾间质纤维化的保护作用及作用机制.方法:采用单侧输尿管结扎(UUO)致肾间质纤维化大鼠模型.将36只大鼠随机分为3组(n=12):假手术组(Sham组)、模型组(UUO组)、槲皮素(剂量100 mg·kg-1·d-1)治疗组(Que组).术后10 d以化学比色法测定梗阻侧肾组织匀浆中羟脯氨酸(Hyp)的含量;HE和Masson染色观察大鼠肾脏病理变化;采用免疫组织化学法、Western blot法检测各组大鼠梗阻侧肾脏α-SMA的表达部位及蛋白表达水平.结果:HE和Masson染色联合图像分析显示大鼠UUO术后10 d梗阻侧肾脏呈现肾间质纤维化,经 Que治疗梗阻侧肾脏病理改变减轻(P＜0.05).免疫组织化学和免疫蛋白印记分析显示经Que治疗梗阻侧肾脏α-SMA染色阳性表达范围和相对表达丰度明显减少(P＜0.01).同时经Que治疗后肾组织匀浆中的Hyp含量降低(P＜0.05).结论:槲皮素可以减轻UUO大鼠肾间质纤维化,其作用机制与抑制肾小管上皮细胞转化成肌成纤维细胞有关.     

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.     

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.     

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.