雄激素对大鼠阴茎海绵体平滑肌中兰尼碱受体1和电压门控钙离子通道1.3表达的影响研究

目的:研究兰尼碱受体1(RyR1)和电压门控钙离子通道1.3(CaV1.3)在去势大鼠阴茎海绵体平滑肌的表达,探讨其在去势后勃起功能障碍发生中的作用。方法:40只8周龄雄性SD大鼠随机均分成:假手术2周组(A组),假手术4周组(B组),去势2周组(C组),去势4周组(D组)。术后实验各组检测血清睾酮(T)水平,免疫组化及RT-PCR技术检测RyR1和CaV1.3在大鼠阴茎海绵体平滑肌中的表达。结果:血清T水平C组[(15.97±5.67)nmol/L]和D组[(2.03±1.57)nmol/L]分别较A组[(90.54±20.13)nmol/L]和B组[(120.35±30.32)nmol/L]显著下降(P<0.05)。RyR1、CaV1.3在各组大鼠阴茎海绵体平滑肌中均有表达,RyR1 mRNA相对表达量灰度比值C组(0.51±0.24)和D组(0.33±0.15)分别较A组(1.53±0.25)和B组(1.37±0.23)显著降低(P<0.05);CaV1.3 mRNA相对表达量灰度比值C组(0.50±0.12)和D组(0.32±0.07)分别较A组(1.33±0.05)和B组(1.25±0.03)显著降低(P<0.05)。RyR1蛋白积分光密度值(IA)C组(120.36±25.78)和D组(67.39±30.54)分别较A组(300.96±135.12)和B组(330.38±128.59)显著降低(P<0.05);CaV1.3蛋白IA C组(103.37±39.52)和D组(67.56±20.15)分别较A组(298.68±126.35)和B组(327.35±117.37)显著降低(P<0.05)。雄激素水平与RyR1、CaV1.3在阴茎海绵体平滑肌中的表达水平具有正相关性。结论:雄激素可能通过RyR1、CaV1.3的表达调控阴茎勃起功能。     

转基因联合泰素帝治疗耐药结直肠癌

目的探讨可溶性血管内皮细胞生长因子受体2基因(sFlk-1)转染联合泰素帝治疗耐药结直肠癌。方法随机均分40只裸鼠至A、B、C、D组,A、B组种植转sFlk-1基因的耐药结直肠癌细胞,C、D组种植耐药结直肠癌细胞,A、C组接受泰素帝(200μg/3d)治疗。70d后比较各组裸鼠瘤重,微血管密度(MVD)和凋亡情况。结果A组瘤重(0．12±0．03)g明显小于B(0．22±0．02)g和C组(1．26±0．03)g、(P＜0．01),但A、B和C组瘤重均小于D组(1．26±0．03)g、(P＜0．01)。A组MVD明显少于其他组,凋亡增加(P＜0．01)。结论sFlk-1基因和泰素帝均能抑制耐药结直肠癌生长,两者联合并非简单作用相加,而是协同增效。     

血管内皮生长因子在卵巢过度刺激综合征发病机理中的作用

目的探讨血管内皮生长因子(VEGF)在卵巢过度刺激综合征(OHSS)大鼠模型发病机理中的作用。方法OHSS组、控制性超排卵(COH)组和对照组每组6只未成年雌性大鼠。采用酶联免疫吸附试验方法测定大鼠血清和腹腔冲洗液VEGF水平;免疫组织化学方法和逆转录聚合酶链反应技术检测卵巢组织VEGF蛋白及其mRNA的表达。结果OHSS组、COH组和对照组大鼠的血清VEGF水平分别为(76.17±18.19)、(50.68±12.83)和(53.68±13.09)ng/L;其中,OHSS组的VEGF水平显著高于COH组和对照组(P<0.05),而COH组和对照组比较无显著性差异。OHSS组、COH组和对照组大鼠腹腔冲洗液VEGF水平分别为(17.12±1.71)(、9.38±5.88)和(6.68±1.86)ng/L;其中,OHSS组的VEGF水平显著高于COH组和对照组(P<0.05),而COH组和对照组比较无显著性差异(P>0.05)。OHSS组大鼠卵巢组织VEGF蛋白表达的平均灰度(97.23±7.26)显著高于对照组(78.55±8.48)和COH组(87.35±7.32)(P<0.05);COH组与对照组比较无显著性差异。OHSS组大鼠卵巢组织VEGF mRNA表达的灰度比(1.23±0.23)显著高于对照组(0.68±0.13)和COH组(0.92±0.07)(P<0.01),COH组也显著高于对照组(P<0.05)。结论VEGF在OHSS发病过程中发挥作用。     

胰腺癌微血管密度及血管内皮生长因子表达

目的　探讨胰腺癌组织中微血管密度 (MVD)和血管内皮生长因子 (VEGF)表达及其与淋巴结转移的关系。方法　采用免疫组织化学法及形态半定量方法对 31例胰腺癌和 7例正常胰腺组织进行MVD记数和VEGF表达检测。结果　胰腺癌组织中MVD记数、VEGF表达率分别为 11.0 5± 4.6 2、83% ,明显高于癌旁组织 5 .40± 1.71、2 0 %和正常胰腺组 6 .19± 1.5 6、14% (P <0 .0 1) ;淋巴结转移组MVD记数 ,VEGF表达分别为 13.0 0± 4.45、2 .0 0± 0 .95 ,明显高于无转移组 9.46±4.15、1.0 5± 0 .17和正常胰腺组 6 .19± 1.5 6、0 .14± 0 .38(P <0 .0 1)。MVD与VEGF表达呈正相关 (r =0 .418,P >0 .0 5 )。结论　MVD、VEGF表达高低可作为判断胰腺癌淋巴结转移、预后的指标。     

血管紧张素Ⅱ受体拮抗剂对大鼠肝硬化时VEGF基因表达的影响

目的　探讨血管内皮生长因子 (vascularendothelialgrowthfactor,VEGF)在肝硬化时的作用及血管紧张素Ⅱ受体拮抗剂Losartan对VEGF基因表达的影响。方法　大鼠肝硬化模型由CCl4诱导 ,41只雄性SD大鼠被随机分为 4组 :对照组 10、模型组 11、及治疗组 2 0 (早期 10、中期 10 ) ,除对照组外所有大鼠均给予 5 0 %CCl4灌胃 ,3ml·kg- 1 ·d- 1 ·次 - 1 ,共 9周。治疗组 :早期组同时血管紧张素受体拮抗剂灌胃 ,中期组于造模中期 (5周 )开始给药 ,用量 10mg·kg- 1 ·d- 1 至处死前。免疫组织化学及RT PCR检测VEGF蛋白、mRNA的表达。结果　肝硬化组VEGF蛋白、mRNA的表达由 0 77±0 10到 1 94± 0 2 0明显高于正常对照组 (P =0 0 0 1) ,而与肝硬化组相比Losartan治疗组VEGF表达明显降低到 1 0 2± 0 10及 0 86± 0 15 (P =0 0 0 1)。结论　肝硬化时VEGF表达增加 ,而Losartan可使其表达降低。     

大肠癌组织微血管密度和血管内皮生长因子表达的研究

目的　研究大肠癌组织的微血管密度 (MVD)和血管内皮生长因子 (VEGF)表达及其与淋巴结转移的关系。方法　采用免疫组织化学链酶亲和素 生物素 酶复合物 (SABC)法对 36例手术切除的大肠癌标本的癌灶中心、癌旁、切缘进行血管标记和染色。结果　癌灶中心MVD计数、VEGF表达分别为 97.2 0± 16 .80、2 .6 0± 0 .70 ,极显著高于癌旁组织 74.6 0± 13.6 0、1.35± 0 .95和切缘组织6 7.2 0± 12 .6 0、0 .92± 0 .90 (P <0 .0 1) ;淋巴结转移组MVD计数、VEGF表达分别为 96 .6 0± 17.90、2 .40± 0 .72极显著高于无淋巴结转移组 72 .0 5± 13.6 0、1.30± 0 .90 (P <0 .0 1)。结论　大肠癌癌灶中心MVD、VEGF呈高表达 ,MVD、VEGF表达高低可能成为判断大肠癌淋巴结转移、预后的指标。     

血管内皮生长因子D基因转移对胆汁性肝硬变大鼠肝纤维化和门静脉压力的影响

目的观察胆汁性肝硬变大鼠门静脉注射血管内皮生长因子D(hVEGF-D)后的促血管形成效应以及对肝纤维化和门静脉压力的影响。方法30只SD大鼠胆总管结扎法制作胆汁性肝硬变模型,治疗组门静脉注射PCHO／hVEGF-D 150μg／只,2周后比较肝组织纤维化程度(苏木素-伊红染色、浸银染色法)、门静脉压力、VEGF蛋白质表达、肝组织微血管密度改变。结果肝组织纤维化程度较注射前明显降低;门静脉压力治疗前为(15．45±1．97)cm H_2O(1 cmH_2O= 0．098 kPa);治疗后则变为(12．56±1．86),差异有统计学意义(P<0．05)。治疗组VEGF蛋白质表达平均染色积分为6．56±1．81,肝硬变对照组4．4±1．02,差异有统计学意义(P<0．01)。治疗组血管计数为14．33±3．24;肝硬变对照为9．2±1．48(P<0．01)。结论胆汁性肝硬变大鼠门静脉注射血管内皮生长因子D表达载体后可以一定程度上促进肝内血管形成、减缓肝纤维化程度降低门静脉压力。     

乳腺癌发生与演进过程中血管生成作用的评价

目的 探讨人乳腺癌前病变、原位癌及浸润性癌中CD34、血管内皮生长因子(VEGF)及其受体Flk-1/KDR的表达变化及血管生成异常与乳腺癌发生发展的关系.方法 应用免疫组织化学技术检测30例正常乳腺、30例普通性增生、30例非典型增生(AH)、20例导管内癌、50例浸润性导管癌组织中微血管密度(MVD)、VEGF及Flk-1/KDR的表达.结果 各组CD34、VEGF及Flk-1/KDR的表达程度不同,浸润性导管癌组最高.随病程演进MVD逐渐增加(P<0.05),VEGF及其受体Flk.1/KDR在血管内皮细胞表达渐进性增高(P<0.05),但在病程初期各主要指标改变不明显,显著变化始于AH阶段.MVD在AH与导管内癌组间差异无统计学意义(P>0.05),VEGF及Flk-1/KDR的表达在AH与导管内癌组间差异有统计学意义(P<0.05).结论 血管生成异常可能是乳腺癌发生过程中的早期事件.VEGF及Flk-1/KDR的表达异常可能是乳腺普通性增生-AH-乳腺癌这一癌性转化过程中血管生成异常的主要始动因素,其可能成为乳腺癌早期诊治的靶标.     

胆管癌微血管生成及其病理学特征与预后的关系

目的探讨胆管癌微血管生成及其病理学特征与预后的关系。方法应用免疫组化法检测50例胆管癌标本的微血管密度、血管内皮生长因子和血管内皮生长因子受体Flk-1／KDR的表达,结合临床病理学资料和随访资料进行分析。结果胆管癌组织和癌旁组织的微血管密度 (34．04±11．08、32．80±9．28)均高于正常组织(11．67±4．64)(P<0．01);血管内皮生长因子和 Flk-1／KDR在肿瘤组织和癌旁组织中的表达均高于正常组织(P<0．01);伴淋巴结转移组微血管密度 (41．07±11．83)高于无转移组(30．93±9．18)(P<0．05);伴神经浸润组微血管密度(37．85±12．04) 高于无浸润组(30．32±8．51)(P<0．05);微血管密度<30和30-39组的生存率高于≥40组(P< 0．05)。结论微血管生成与胆管癌的发生、发展和预后密切相关。     

肺纤维化对大鼠阴茎勃起功能的影响

目的:研究肺纤维化对大鼠勃起功能的影响及其机制。方法:12周雄性SD大鼠40只,随机分为4组:正常对照4周组(A组)、6周组(B组)和肺纤维化大鼠4周组(C组)、6周组(D组)各10只,分别用生理盐水(A、B组)及博莱霉素(5 mg/kg)气管内注入,饲养4周(A、C组)、6周(B、D组)后,测定大鼠血清睾酮、动脉血气分析、阴茎海绵体内压/平均颈动脉压(ICP/MAP),取阴茎标本测定NOS活性及cGMP含量,实时荧光PCR检测eNOS、iNOS和nNOS的mRNA在阴茎海绵体的表达,W estern印迹检测阴茎海绵体eNOS蛋白的表达。结果:电刺激的3 V,5 V C组ICP/MAP×100(16.37±2.19,27.19±3.18)较A组(30.78±2.66,50.09±6.97)显著降低(P<0.05),D组ICP/MAP×100,3 V,5 V(10.17±1.31,17.40±1.74)较B组(31.45±3.07,51.23±7.23)显著降低(P<0.05),D组ICP/MAP×100值较C组显著降低(P<0.05)。C组PaO2(75.50±13.87)mmHg较A组(103.80±6.88)mmHg显著降低(P<0.05),D组PaO2(83.60±5.50)mmHg较B组(102.70±5.77)mHg显著降低(P<0.05)。C组血清睾酮水平(391.1±264.7)ng/d l较A组(175.9±53.0)ng/d l显著升高(P<0.05),D组血清睾酮水平(745.4±408.8)ng/d l较B组(177.8±52.3)ng/d l显著升高(P<0.05),同时D组血清睾酮水平较C组显著升高(P<0.05)。C组NOS活性及cGMP含量[(1.50±0.14)U/mg prot,(35.69±3.64)pmol/mg]较A组[(2.66±0.39)U/mg prot,(51.10±7.22)pmol/mg]显著降低(P<0.05),D组NOS活性及cGMP含量[(1.40±0.20)U/mg prot,(34.55±4.30 pmol/mg)]较B组[(2.75±0.36)U/mg prot,(52.15±6.86)pmol/mg]显著降低(P<0.05),C组与D组比较NOS活性及cGMP含量无显著性差异(P>0.05)。C组eNOS蛋白表达量(0.79±0.01)较A组(0.87±0.01)显著降低(P<0.01),D组eNOS蛋白表达量(0.71±0.02)较B组(0.88±0.01)显著降低(P<0.05),D组较C组eNOS蛋白表达量显著降低(P<0.05)。C组eNOS mRNA表达量(4.46±0.92)较A组(2.61±0.68)显著升高(P<0.05),D组eNOS mRNA(2.79±0.60)表达量与B组(2.69±0.65)无显著性差异(P>0.05),nNOS及iNOS的mRNA表达量在A、B组与C、D组间均无显著性差异(P>0.05)。结论:肺纤维化可通过抑制阴茎海绵体eNOS蛋白的表达、降低总NOS活性及cGMP含量等机制抑制阴茎勃起功能。     

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.