骨髓单个核细胞自体移植促进心脏血管再生

目的探讨骨髓单个核细胞自体移植于梗死心肌后实现血管再生的能力。方法结扎45只5月龄日本大耳白兔的冠状动脉左前降支建立心肌梗死模型，随机分为骨髓单个核细胞自体移植组(5-溴-2’-脱氧尿嘧啶核苷标记的自体骨髓单个核细胞直接心肌注射至梗死周边区域)，心肌梗死未治疗组及假手术组，分别在细胞移植后2、4、8周时处死，应用免疫组织化学方法检测骨髓单个核细胞在梗死心肌组织中的分化、毛细血管密度以及细胞因子的表达。结果骨髓单个核细胞在梗死心肌组织中分化为血管内皮细胞和血管平滑肌细胞。在骨髓单个核细胞移植早期，心肌白细胞介素-1β(IL-1β)、碱性纤维母细胞生长因子(bFGF)、血管内皮生长因子(VEGF)表达水平显著增高。细胞移植后4、8周骨髓单个核细胞移植组毛细血管密度明显高于心肌梗死未治疗组及假手术组。结论骨髓单个核细胞自体移植于梗死心肌区能促进血管再生，改善侧支循环。     

犬自体骨髓干细胞在缺血肢体中新生血管形成中的作用

目的:探讨犬自体骨髓干细胞在缺血组织的新生血管形成中的作用.方法:抽取犬骨髓,经免疫磁珠系统分离出CD 34细胞,体外扩增并向血管内皮细胞诱导分化;建立犬双下肢缺血动物模型,将诱导分化细胞移植入一侧缺血肢体中作为实验组,另一侧缺血肢体植入等体积的生理盐水作为自体对照组.移植后6周,检测缺血肢体中新生血管的形成.结果:细胞移植后6周,动脉造影显示实验组缺血肢体侧枝循环增加,明显多于对照组.微血管密度检测实验组为(14±2.3)个/高倍镜视野,明显高于对照组(6±2.1)个/高倍镜视野(P<0.05).激光共聚焦显微镜证实缺血肢体中移植的自体骨髓干细胞参与了新生血管形成.结论:自体骨髓干细胞移植可以促进缺血肢体组织中的新生血管形成.     

骨骼肌卫星细胞梗死心肌移植的细胞因子分泌及血管再生作用

目的　研究骨骼肌卫星细胞梗死心肌移植的胰岛素样生长因子(IGF)-1、碱性纤维母细胞生长因子(bFGF)分泌及血管再生的作用。方法　骨骼肌卫星细胞经结扎的冠状动脉左前降支远端灌注移植入梗死区,2、4、8周后取标本,应用免疫组化学方法检测细胞因子表达及梗死区血管密度。结果　骨骼肌卫星细胞移植2、4、8周后梗死区IGF-1和bFGF表达分别为81.68±3.34、96.87±7.78、90.43±7.36及81.87±3.58、65.66±4.57、74.20±6.41,明显高于对照组(P＜0.01);同时,移植2、4、8周后梗死区血管密度高于对照组(P＜0.05)。结论　骨骼肌卫星细胞梗死心肌移植除有心肌再生外,尚可通过细胞因子分泌对梗死心肌起到积极作用。     

骨髓间质干细胞移植对香猪急性心肌梗死后心肌结构和心功能的影响

目的 移植自体骨髓间质干细胞(BMSCs)到香猪急性心肌梗死区内,研究移植BMSCs对心肌结构和心功能的影响. 方法将24只贵州香猪采用计算器随机法分为实验组(n＝12)和对照组(n＝12),抽取香猪自体骨髓,经体外分离出BMSCs并培养和经5-氮胞苷(5-azacytidine)转化,利用结扎左前降支(LAD)的方法建立急性心肌梗死动物模型,经LAD和梗死区多点注射的方法将实验组香猪注射BMSCs(细胞总数2×106个),对照组注射等量的细胞培养液.3周和6周后,用超声心动图(UCG)观察两组移植后心肌结构和心功能改变的情况. 结果实验组左心室射血分数、左心室短轴缩短率和室壁增厚率明显高于对照组;左心室室壁、室间隔厚度和心室腔的大小在两组之间也存在明显差别,实验组室壁和室间隔厚度明显大于对照组,而心室腔小于对照组. 结论 BMSCs梗死区心肌移植后可减轻心室重构的进程,减轻心肌的变薄程度,使心室腔未明显扩大.BMSCs移植还可增加心肌的收缩力,改善心功能.     

自体内皮祖细胞移植对急性心肌梗死近、中期心肌收缩力的影响

目的比较自体内皮祖细胞（EPCs）移植急性心肌梗死区域后近、中期心功能恢复的程度。方法将SD大鼠120只随机分为实验组和对照组（每组60只），抽取自体外周血，体外分离出内皮祖细胞。开胸结扎左冠状动脉前降支，实验组用自体内皮祖细胞经局部注射移植入急性心肌梗死区域；对照组以IMDM（Iscove＇s modified Dulbecco＇s Medium）作对照。术后3、6周、6、8和12个月取标本，体外药物刺激离体肌条检测心肌收缩情况。免疫组织化学法、计算机图象分析检测组织血管内皮生长因子（VEGF），碱性成纤维生长因子（bFGF），血管内皮第八因子（Ⅷ因子）的表达。结果实验组梗死区3、6周、6个月bFGF、VEGF灰度值明显高于对照组（P〈0．01），微血管计数较对照组明显增多（P〈0．01），心肌收缩力明显较对照组增强（P〈0．01），且随时间推移恢复程度增加（P〈0．05）。但从8个月开始，实验组以上指标不再明显增加。结论自体内皮祖细胞移植可能通过血管发生、血管新生等方式增加心肌细胞的收缩力，但中期疗效并不能随着时间推移而持续增加，在较长时间内保持稳定。     

骨髓间充质干细胞移植重建大鼠缺血心肌的实验研究

目的　探讨大鼠骨髓间充质干细胞 (MSCs)移植于缺血心肌后的增殖分化情况和对缺血心肌细胞的修复重建能力及心功能改善情况。　方法　实验组为将体外培养SD大鼠的MSCs经溴氮胞苷 (BrdU)标记后显微注射于结扎冠状动脉后的大鼠缺血心肌内 ,并以无血清培养基注射动物为对照组。 4周后观察移植细胞的分化情况 ,并通过超声多普勒、心肌核素显像、免疫组化和新生血管形成情况来检测心功能变化。　结果　实验组MSCs移植 4周后 ,在缺血心肌区内可发现不同分化阶段的心肌样细胞。超声检查发现实验组的左室射血分数 (LVEF)的改善明显好于对照组 (P <0 0 5 ) ;SPECT显示实验组心肌核素摄取显著高于对照组 (P <0 0 1) ;在促新生血管形成方面 ,实验组也明显好于对照组(P <0 0 5 )。　结论　骨髓间充质干细胞移植于缺血心肌后可重建缺血心肌 ,增加心肌灌注 ,显著改善心功能。     

共价结合生长因子的胶原补片修补大鼠左心室室壁瘤的实验研究

目的 比较采用碳化二亚胺法(EDC法)处理共价结合不同生长因子的胶原补片修补大鼠左心室室壁瘤后的再血管化情况,及其对大鼠左心功能的影响.方法 直径5 mm的圆形胶原补片经EDC法处理作对照组,再分别结合血管内皮细胞生长因子(VEGF)或VEGF+碱性成纤维细胞生长因子(bFGF)后作实验组.成年雄性SD大鼠行左冠状动脉前降支结扎制作透壁心梗模型.4周后,心脏彩超筛选心梗面积占左心室前壁25％～ 35％者入选.随机分成3组,以不同补片行室璧瘤修补,对照组(8只),VEGF组(10只),VEGF+ bFGF组(10只).术后1周、2周、4周分别行心脏彩超监测左心功能,至实验终点取材,免疫荧光法检测补片边缘毛细血管(vWFⅧ染色)及成熟血管(SMA染色)的生成情况.结果 全组死亡比例15％(6/40只).修补1周后,3组动物心功能均明显改善;4周后,结合生长因子的两组心功能较对照组明显改善(对照组对VEGF组,P＜0.05;对照组对VEGF+ bFGF组,P＜0.01).组织学检查显示,两组结合有生长因子的毛细血管生成情况均较对照组明显改善(P ＜0.05);VEGF+bFGF组的再血管化较其他两组明显改善(P＜0.01).相关性分析显示,大鼠心功能参数(FS)与再血管化呈正相关(P=0.0297,r2=0.998).结论 EDC法可有效改善胶原补片的机械性能,共价结合生长因子后可显著增加补片内血管生成,再血管化有助于左心功能的维持.     

骨髓间充质干细胞自体移植治疗心肌梗死的实验研究

目的探讨兔骨髓间充质干细胞(MSCs)移植至缺血心肌后的增殖分化情况,对缺血心肌细胞的修复重建能力及心功能改善情况。方法将20只新西兰白兔随机分为骨髓间充质干细胞移植组(MSCs组,n=10)和对照组(n=10),采用结扎冠状动脉左前降支(LAD)制备心肌梗死模型,2周后分别将Dil标记的1×106个细胞悬液400μl或等量L-DMEM培养基用微量注射器注入梗死灶边缘,于建模前、建模后2周、细胞移植后2、4周采用多普勒超声心动图检测左心室收缩期末内径(LVESD)、左心室舒张期末内径(LVEDD),计算左心室射血分数(LVEF)、左心室短轴缩短率(LVFS)评价心脏收缩功能,同时进行心肌声学造影评价心肌组织的血流灌注情况。细胞移植后8周处死所有动物,病理学检查移植细胞在梗死区的生长状况。结果多普勒超声心动图检测结果显示:两组动物建模前、建模后2周LVEF、LVFS差异无统计学意义(0.72±0.08vs.0.71±0.04,0.56±0.11vs.0.55±0.09;0.35±0.06vs.0.35±0.04,0.24±0.08vs.0.23±0.03,P>0.05),细胞移植后2、4周MSCs组LVEF、LVFS值均明显高于对照组(0.71±0.05vs.0.60±0.05,0.72±0.07vs.0.62±0.08;0.34±0.03vs.0.29±0.01,0.35±0.06vs.0.27±0.05,P<0.05);病理学检查见自体MSCs移植8周后存活于梗死心肌中,表达肌细胞特异性标志,并且能显著增加瘢痕区毛细血管密度(38.6±7.6/mm2vs.21.4±3.9/mm2,P<0.05),心肌声学造影亦显示梗死局部血流灌注MSCs组较对照组明显改善。结论自体MSCs移植缺血心肌中可向心肌细胞分化,增加心肌血流灌注,改善心脏收缩功能。     

大网膜联合组织工程心肌移植改善心肌梗死后大鼠心功能

目的 将骨髓间充质干细胞(MSCs)种植于共聚乙交酯-丙交酯(PLGA)补片上构建组织工程心肌(EHT),在大鼠心肌梗死模型上观察大网膜增加EHT血供,改善微环境后对心脏间质胶原重塑及心功能的影响,为心肌梗死的外科治疗提供新的途径. 方法 结扎SD大鼠左冠状动脉,制作心肌梗死模型.以大鼠MSCs为种子细胞构建EHT,将符合心肌梗死标准的18只鼠随机分成3组,每组6只,A组:网膜包裹EHT;B组:单纯EHT移植;对照组:单纯心肌梗死;另设假手术组(n=6):仅开胸,不结扎冠状动脉及EHT移植.EHT植入后4周,用二维超声心动图检测心功能,彩色室壁运动(CK)方法检测梗死部位心室壁运动,取标本做天狼猩红染色在光学显微镜下观察心肌改变. 结果 A组EHT植入后4周部分PLGA纤维降解,梗死部位心肌间质胶原含量较B组和对照组明显减少(P<0.05).CK检查显示A组梗死部位心室壁运动较B组和对照组明显改善(P<0.05);A组左心室收缩期末内径(LVESD)和左心室舒张期末内径(LVEDD)较对照组和B组明显减小(P<0.05),左心室射血分数(LVEF)、左心室缩短分数(LVFS)较对照组和B组明显增大(P<0.05). 结论 大网膜包裹MSCs-PLGA构建的EHT覆盖于梗死心肌表面能改善心肌梗死后间质胶原重塑和梗死部位心室壁运动,有利于心功能的恢复.     

脐血间质干细胞移植于梗死心肌后对心肌基本结构的保护作用

目的 探讨经诱导分化为肌源性干细胞的脐血间质干细胞（mesenchymal stem cell，MSC）移植于梗死心肌后对梗死心肌组织结构改变的影响。方法 将36只成年杂种犬随机分为脐血MSC移植组（移植组）和对照组，每组各18只。移植组：用5一氮杂胞嘧啶核苷（5-azacytidine，5-aza）诱导分化后的脐血MSC，经结扎的犬冠状动脉左前降支远端灌注移植入梗死区；对照组：给予等量含0．02％的4，6-联脒-2-苯基吲哚（DAPI）的IMDM培养液注射。于移植2周、4周和8周时用Nagar—Olsen染色法观察心肌组织基本结构改变，用免疫细胞化学染色法观察残存心肌细胞结蛋白（desmin）分布变化。结果 Nagar—Olsen染色结果显示：移植组梗死心肌组织内弹力纤维、胶原纤维排列整齐、规律；对照组排列较紊乱、无规律，部分发生融合。移植组梗死区域心肌细胞结蛋白表达明显高于对照组（P〈0．01），而两组正常区域心肌细胞结蛋白表达差别无统计学意义（P〉0．05）。结论 脐血MSC在体外经5-aza诱导分化为肌源性干细胞并移植入梗死心肌后，对梗死心肌组织结构具有保护作用。     

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.