门静脉压力改变对门静脉高压症肠道通透性的影响

目的　观察门静脉压力改变对门静脉高压症患者肠道通透性的影响。　方法　门静脉高压症患者 2 0例分为 2组 ,每组 10例 ,A组采用经颈内静脉肝内门体分流术 (transjugularintrahepaticportosystemicshunt,TIPS)加改良Sugiura联合治疗 ,B组行改良Sugiura治疗。分别于术前、TIPS后 2周和改良Sugiura术后 2周行肠道通透性检查 ;2 0例健康志愿者作对照。　结果　门静脉高压症患者较健康志愿者肠道通透性明显升高 (0 132± 0 110vs 0 0 32± 0 0 18,P <0 0 1)。A组患者TIPS术后 2周门静脉压力和肠道通透性均显著降低 (P <0 0 5 ) ;改良Sugiura术后 2周 ,2者无显著变化 ,但较术前明显降低 (P <0 0 5 )。B组患者改良Sugiura术后 2周肠道通透性和术前相比无显著变化。A、B组患者术前肠道通透性相比无显著差异 ,改良Sugiura术后 ,A组明显降低 (P <0 0 5 )。研究还发现门静脉压力与肠道通透性之间有显著相关性 (r=0 6 2 7,P <0 0 1)。　结论　研究表明TIPS加改良Sugiura术降低门静脉压力 ,改善肠道通透性 ,提高临床疗效。     

一氧化氮在门静脉高压症发病中的作用

目的　探讨一氧化氮在门静脉高压症发病中的作用。　方法　 75例门静脉高压症患者 ,术中胃网膜静脉插管测定门静脉压力 ,检测外周动静脉和门静脉血中内毒素和NO2 -/NO3-的含量。　结果　 ( 1)门静脉高压症患者的血中内毒素和NO2 -/NO3-的水平 [( 0 2 4 9± 0 112 )Eu/ml和( 5 5 9± 2 6 2 ) μmol/L]均显著高于对照组 ,且门静脉血中水平最高。 ( 2 )门静脉高压症患者门静脉压力[( 3 5 5± 4 4 )cmH2 O]与门静脉血NO2 -/NO3-的水平呈显著正相关 (n =2 5 ,r =0 5 5 ,P <0 0 1) ,二者在术后的变化量也呈正相关 (r =0 5 7,P <0 0 5 )。 ( 3 )门静脉高压症患者白蛋白水平与NO2 -/NO3-呈负相关 (n =75 ,r=- 0 3 5 ,P <0 0 1) ,且有腹水组的NO2 -/NO3-水平 [( 72 4± 2 0 3 ) μmol/L]较无腹水组 [( 5 0 3± 2 1 0 ) μmol/L]为高。　 结论　门静脉高压症患者血中内毒素和NO的水平升高 ,后者可能参与了门静脉压力的异常升高且与肝功能损害有关。     

前列环素与门静脉高压症高动力循环的关系

目的　探讨前列环素 (PGI2 )和一氧化氮 (NO)在门静脉高压症高血流动力循环中的作用。　方法　 66只雄性SD大鼠随机分成 :肝内型门静脉高压症组 (IHPH组 )、肝前型门静脉高压症组 (PHPH组 )和假手术组 (SO组 )。模型制备 1周后再随机分为 3个亚组 ,即对照组、一氧化氮合酶抑制剂L NNA组、消炎痛组。用药 1周后测定股动脉血浆 6 酮 前列腺素F1α(6 keto PGF1α)和NO2 - /NO3- 浓度 ,应用同位素微球技术行血流动力学研究 ,并对NO、PGI2 水平与血流动力学参数行Pearson相关分析。　结果　 (1 )在基础状态下 ,血浆 6 keto PGF1α浓度 ,IHPH鼠 [(1 1 2 3 85± 1 53 64)pg/ml]和PHPH鼠 [(891 88± 83 1 1 )pg/ml]均显著地高于SO鼠 [(72 5 53± 1 0 5 54)pg/ml] ,P <0 0 5 ;血浆NO2 - /NO3- 浓度 ,IHPH鼠 [(73 34± 4 31 ) μmol/L]和PHPH鼠 [(75 2 1± 6 89) μmol/L]均显著高于SO鼠[(58 79± 8 47) μmol/L] ,P <0 0 5。 (2 )与对照组比较 ,L NNA与消炎痛均显著地降低IHPH与PHPH 2组鼠血浆 6 keto PGF1α和NO2 - /NO3- 的浓度 ,P <0 0 5 ;降低IHPH、PHPH 2组鼠的心脏指数 (CI)、门静脉压力 (FPP)和门静脉血流量 (PVI) ,P <0 0 5 ;显著地增高这 2组鼠的平均动脉压 (MAP)、总外周血管阻力 (TPR)和内脏血     

PDGF mRNA及TGF-β在门静脉高压症病人内脏血管重构中的表达及意义

目的　研究门静脉高压症病人脾动脉血小板源性生长因子 (PDGF)mRNA及转化生长因子 β(TGF β)的表达并探讨与门静脉高压血管病变的关系。方法　肝硬化门静脉高压病人 37例及外伤性脾破裂病人 17例 ,取脾门处脾动脉。原位杂交法检测PDGFmRNA的表达 ,免疫组化法检测TGF β的表达 ,经计算机图像处理后行统计学分析。 结果　对照组PDGFmRNA及TGF β表达为阴性或弱阳性 ,门静脉高压组PDGFmRNA及TGF β表达均明显增强 ,为中到强阳性 ,平滑肌层有明显表达。图像光密度值有显著性差异 (PDGFmRNA :73 2 6± 12 35vs 18 2 7± 5 86 ,P <0 0 5 ;TGF β:6 5 36± 9 74vs 12 17± 6 5 5 ,P <0 0 5 )。结论　门静脉高压内脏血管PDGFmRNA及TGF β的表达增加可能为高动力循环、毒血症等引起的血管损伤所诱导 ,并可加重平滑肌细胞过度增生及纤维化 ,在门静脉高压血管病变及细胞表型转化过程中有一定意义。     

术前高压氧治疗对肝硬化门静脉高压症病人的影响

目的 研究术前高压氧（HBO）治疗对肝硬化门静脉高压病人的作用,并探讨其机理。方法 选取肝硬化门静脉高压病人12例接受HBO治疗。观察肝功指标、内毒素和NO水平、肠粘膜通透性、网状内皮系统功能及血流动力学指标在HBO前后变化;另设正常对照组8例,比较两组间肠粘膜通透性、网状内皮系统功能的差异。结果 （1）与正常秩序正常组相比,肝硬化组的肠粘膜通透性增高,而网状内皮系统吞噬功能降低,且内毒素与肠粘膜通透性呈正相关（r＝0．504,P＝0．012）。（2）HBO治疗后,病人的肝功改善;网状内皮系统功能恢复,内毒素、NO较前下降;脾脏厚度、门静脉宽度及门静脉血流量减少。（3）统计分析发现NO与内毒素、脾脏厚度及门静脉血流速度呈正相关（r1＝0．597,P1＝0．000;r2＝0．472,P2＝0．027;r3＝0．463,P3＝0．030）,与门静脉血流速度呈负相关（r＝－0．443,P＝0．030）。结论 HBO能改善肝硬化病人的肝脏功能,改善门静脉高压和高动力循环状态。其作用机理可能与改善肝脏供氧,增加网状内皮系统功能,减少血中内毒素及NO有关。     

门静脉高压症病人肝内血管内皮细胞凋亡的研究

目的　研究门静脉高压症病人肝组织内血管及肝窦壁内皮细胞的凋亡及其对肝微循环的影响。方法　对 37例门静脉高压症病人、10例正常人肝组织 ,用TUNEL法检测血管内皮细胞及肝窦壁内皮细胞凋亡 ,免疫组化法检测Bax和Bcl 2基因的蛋白表达。结果　肝硬化门静脉高压症病人 ,门管区血管内膜破坏、断裂 ,内皮细胞脱落。管腔内血栓形成。血管壁和肝窦壁内皮细胞TUNEL 阳性细胞数为 (2 9 2 9± 4 15 ) % ,与对照组仅 (0 5± 0 2 ) % ,有显著性差异 (P <0 0 0 1) ;门管区血管内皮细胞和肝窦壁内皮细胞Bax和Bcl 2强阳性表达率分别为 (33 5 1± 5 6 9) %和 (2 4 6 4± 5 87) % ,对照组均为阴性 (P <0 0 0 1)。结论　肝硬化门静脉高压症病人门管区内皮细胞和肝窦壁内皮细胞凋亡和坏死明显增加 ,内皮细胞的凋亡和坏死激活凝血系统 ,促使血栓形成 ,从而破坏了肝脏微循环。     

生长激素抗肝纤维化的作用及其机制

目的　探讨重组人生长激素 (rhGH)对肝硬化大鼠在肝功能、门静脉高压等方面的治疗作用及其可能的机制。方法　雄性SD大鼠建立肝硬化模型 ,随机分组 ,分别给予NS、rhGH (333ng/KgBW ,ip ,qd× 7d)处理。 结果　rhGH处理前后肝硬化肝组织GHR的配体结合容量 [fmol/mg ,(31± 4 )vs .(4 0± 7) ]及其mRNA量 (iOD ,pixel)均显著升高 (2 3± 3)vs.(4 2± 8) ;P <0 0 5 ,肝硬化大鼠血清白蛋白 (g/L )显著升高 (2 9± 4 )vs .(37± 7) ;P <0 0 5、ALT活性 (U/L)显著降低 (89± 15 ,6 9± 7;P <0 0 5 ) ,肝硬化肝组织丙二醛含量 (nmol/mg)显著降低 (18 7± 3 2 ,12 0± 2 2 ;P <0 0 5 )、超氧化物歧化酶活性 (U/mg)显著升高 (82 4± 10 8,10 2 9± 76 ;P <0 0 5 )、胶原纤维相对含量 (% )显著降低 (2 2 30± 3 86vs.14 70± 2 0 7;P <0 0 5 ) ,肝硬化大鼠的门静脉压 (cmH2 O)亦显著降低 (14 4± 2 0vs.9 3± 1 5 ;P <0 0 5 )。结论　药理剂量的rhGH能够促进肝硬化大鼠的白蛋白合成、改善肝细胞功能 ,有助于抑制肝组织纤维化、缓解门静脉压力。     

肝硬化大鼠肝脏内皮素受体基因的表达与门静脉压力的关系

目的　研究四氯化碳诱导的肝硬化大鼠肝脏内皮素(endothelin, ET)受体基因的表达,并探讨其与门静脉压力的关系。方法　采用逆转录多聚酶链反应(RT PCR)测定大鼠肝组织 ETA受体和ETB受体mRNA的表达水平, 并测量门静脉压力。结果　肝硬化大鼠肝组织 ETA受体(0 4245±0 0612 vs 0 2792±0 1115,P<0 05) 和 ETB受体(0 5984±0 1047 vs 0 2938±0 1399,P< 0 05) mRNA 的表达均较对照组均显著升高;肝硬化大鼠门静脉压力较正常大鼠明显升高(16 08±2 19 vs8 25±2 56 cmH2O,P<0 05),并且ETA受体mRNA的表达与门静脉压力显著正相关(r=0 8074,P<0 05)。结论　四氯化碳诱导的肝硬化大鼠肝组织ET受体 mRNA的表达显著升高,并且 ETA受体 mRNA的表达与门静脉压力显著正相关, 表明 ET受体的高表达在门静脉高压症的发病机制中起重要作用。     

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目的　探讨失血性低血容量休克病人血浆一氧化氮 (NO)浓度与预后的关系。方法　 2 0 0 1年 7月至2 0 0 2年 1月 ,应用比色法测定 2 9例失血性低血容量休克病人血浆NO浓度 ,与 2 0例择期手术病人进行对照 ,观察NO与多器官功能障碍综合征 (MODS)的关系。结果　休克组血浆NO浓度 ( 74 2± 46 9) μmol/L ,较对照组( 5 0 5± 2 3 3 ) μmol/L明显升高 (P <0 0 5 )。休克组发生MODS病人血浆NO浓度 ( 90 4± 5 3 5 ) μmol/L ,较未发生MODS者血浆NO浓度 ( 5 4 2± 2 7 9) μmol/L明显升高 (P <0 0 5 )。 结论　失血性低血容量休克NO产生过多可能参与MODS的发生     

局部肾素与血管紧张素原mRNA在肝硬化门静脉高压症患者中的表达及其意义

目的探讨肝硬化门静脉高压症 (PH)对局部肾素血管紧张素系统 (LRAS)活性的影响。方法采用逆转录聚合酶链反应方法检测肝硬化门静脉高压症患者肝脏、脾脏动、静脉组织局部肾素与局部血管紧张素原mRNA的表达情况。结果　对照组内局部肾素mRNA在肝脏中最低(0 19± 0 12 ) ,显著低于脾脏动、静脉组织 [(0 4 5± 0 12 )及 (0 39± 0 12 ) ],P <0 0 5 ;局部血管紧张素原mRNA以肝脏最高 (0 6 4± 0 2 1) ,显著高于脾脏动、静脉组织 [(0 32± 0 15 )及 (0 4 1± 0 18) ],P <0 0 5。肝硬化门静脉高压症组肝脏、脾动脉、脾静脉局部肾素mRNA分别为 (0 78± 0 2 8)、(0 86± 0 35 )、(0 81± 0 2 2 ) ,显著高于对照组 ,P <0 0 5 ;肝硬化门静脉高压症组肝脏、脾动脉、脾静脉局部血管紧张素原mRNA量分别为 (0 96± 0 2 5 )、(0 83± 0 18)、(0 79± 0 2 3) ,亦显著高于对照组 ,P<0 0 5。结论肝硬化门静脉高压患者局部肾素与血管紧张素原mRNA表达增强 ,并可能促进肝硬化门静脉高压症时内脏血管病变的形成。     

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.     

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.