依那西普对磨屑诱导巨噬细胞分泌肿瘤坏死因子的影响

目的 探讨依那西普(etanercept)对人工关节无菌性松动的影响.方法 分离、培养小鼠腹腔巨噬细胞,分为5组.A组为单纯巨噬细胞组,B组为细胞 钛颗粒组,C组为细胞 钛颗粒 10ng/ml依那西普组,D组为细胞 钛颗粒 100 ng/ml依那西普组,E组为细胞 钛颗粒 1000 ng/ml依那西普组.培养18小时后,用酶联免疫吸附试验检测细胞培养上清液中肿瘤坏死因子含量.结果 A、C、D、E组肿瘤坏死因子含量明显低于B组(P＜0.001),E组肿瘤坏死因子含量明显低于C组和B组(P＜0.001).结论 磨屑可刺激巨噬细胞分泌肿瘤坏死因子,依那西普能够呈剂量依赖地有效抑制磨屑诱导的巨噬细胞分泌肿瘤坏死因子,有望成为预防人工关节无菌性松动的药物.     

NF-κB受体激活因子配体抗体防治人工关节无菌性松动的实验研究

目的人工关节无菌性松动与破骨细胞激活后假体周围骨溶解有关,而NF-κB受体激活因子配体(receptor activator of NF-κB ligand,RANKL)/NF-κB受体激活因子(receptor activator of NF-κB,RANK)信号通路是激活破骨细胞的主要途径,通过建立小鼠气囊植骨模型模拟人工关节无菌性松动环境,观察RANKL抗体抑制炎性反应、减轻溶骨反应的作用。方法取8～10周龄雌性BALB/c小鼠60只(体重18～20 g),取其中20只小鼠颅骨制备骨片,作为气囊植骨供体;剩余40只小鼠随机分为阴性对照组(A组)、阳性对照组(B组)、RANKL抗体低剂量组(C组)和RANKL抗体高剂量组(D组),每组10只。于各组小鼠背部制备2 cm×2 cm大小的气囊后植入1片骨片;于植骨后1 d,A组气囊内注射0.5 mL PBS液;B、C、D组注射0.5 mL钛颗粒悬液。钛颗粒悬液注射前2 d,C、D组气囊内分别注射0.1 mL浓度为50μg/mL和500μg/mL的RANKL抗体,每天1次,连续2 d;A、B组注射0.1 mL PBS液。于植骨后14 d处死全部小鼠,取出植入颅骨骨片和周围囊壁组织,进行大体及组织学观察,并行颅骨骨溶解、骨胶原含量及破骨细胞含量分析。结果各组小鼠均存活至实验完成,切口愈合良好。大体观察见A、C、D组小鼠囊壁炎性反应较轻,偶见渗出和新生血管增生;B组炎性反应严重,见渗出以及新生血管增生。组织学观察见A、C、D组小鼠囊壁炎性细胞浸润及增厚不明显,骨胶原丢失量和破骨细胞含量少;B组大量炎性细胞浸润,囊壁增厚,骨胶原丢失量和破骨细胞含量多。B组炎性细胞数、囊壁厚度、骨胶原丢失量以及破骨细胞含量与A、C、D组比较,差异均有统计学意义(P<0.05)。结论 RANKL抗体可阻断小鼠气囊植骨模型的炎症信号传导通路,有效抑制磨损颗粒所致骨溶解。     

红霉素抑制磨损颗粒诱发体内骨溶解的研究

[目的]通过小鼠体内磨损颗粒颅骨溶解模型研究红霉素(erythromycin,EM)抑制磨损颗粒诱发骨溶解的效果。[方法]24只8周龄的C57BL/J6雄性小鼠随机分为4组:聚甲基丙烯酸甲酯(polymethyl-methacrylate,PM-MA)组接受PMMA30 mg颗粒植入颅顶部,PMMA 2EM组接受30 mg PMMA颗粒植入加每天EM2 mg/kg腹腔内注射,PMMA 10EM组接受PMMA30 mg颗粒植入加每天EM10 mg/kg腹腔内注射,对照组接受假手术。7 d后取出颅骨进行病理学分析。[结果]颅骨破坏面积对照组为0.079 mm2±0.011 mm2,PMMA组0.335 mm2±0.129 mm2,PM-MA 2EM组0.094 mm2±0.019 mm2,PMMA 10EM组0.091 mm2±0.028 mm2。对照组颅骨实验区域内破骨细胞计数为5.3±1.0个,PMMA组为19.2±5.3个,PMMA 2EM组为6.6±1.1个,PMMA 10EM组为6.1±1.9个。与对照组相比,PMMA颗粒可以诱发骨溶解(P<0.001),而EM治疗可以抑制PMMA颗粒诱发的颅骨溶解(P<0.001),及破骨细胞生成(P<0.001)。[结论]EM可以抑制PMMA磨损颗粒诱发的骨溶解。     

唑来膦酸钠在抑制钛颗粒诱导骨溶解中作用的体外实验研究

目的：研究唑来膦酸钠（ ZOL）对钛颗粒诱导的骨溶解的影响。方法分离6～8周C57BL/6J小鼠长骨中的前体破骨细胞（ OCP）并分为6组,A组：OCP＋细胞培养液,B组：OCP＋巨噬细胞集落刺激因子（M-CSF）＋NF-κB 受体活化因子配体（RANKL）＋细胞培养液,C组：OCP＋钛颗粒＋细胞培养液,D组：OCP＋上清液（钛颗粒刺激巨噬细胞24 h后上清液）＋细胞培养液,E组：OCP＋M-CSF＋RANKL＋ZOL＋细胞培养液,F组：OCP＋上清液＋ZOL＋细胞培养液。每组细胞分别接种在玻璃盖玻片、皮质骨磨片和含骨检测表面的96孔板上,10 d后检测玻璃盖玻片上细胞抗酒石酸磷酸酶（ TRAP）的表达及皮质骨磨片上骨吸收陷窝的形成,并以骨检测表面的骨吸收面积为指标比较各组破骨细胞的骨吸收活性。结果 B组、D组、E组和F组的OCP均能分化为能被TRAP染色成阳性的破骨细胞并形成骨吸收陷窝,其余组均未发现TRAP染色阳性的破骨细胞和骨陷窝。加入ZOL的F组骨吸收面积（5.54％±1.25％）较D组（10.34％±1.69％）明显减少,差异具有统计学意义（t＝5.61,P＜0.01）。结论在体外实验中钛颗粒并不能直接刺激前体破骨细胞向破骨细胞转化;唑来膦酸钠可以抑制钛颗粒诱导的骨溶解作用。     

不同浓度金属磨损颗粒对破骨细胞体外分化的影响

[目的]观察不同浓度金属磨损颗粒对RAW 264.7在体外分化成破骨细胞的影响,明确浓度与破骨细胞分化数量的关系.[方法]真空球磨法制备人工关节磨损颗粒:RANKL诱导RAW 264.7体外分化成破骨细胞,通过TRAP染色,电镜扫描检测骨片吸收陷窝来鉴定破骨细胞;不同浓度人工关节磨损颗粒混悬液作用RAW 264.7,并用RANKL诱导后第7 d,TRAP染色后,光镜下计数破骨细胞数量.[结果]不同浓度磨损颗粒作用于RAW 264.7 7 d后,显微镜下计数破骨细胞数量,结果显示随着磨损颗粒混悬液浓度增加,RANKL诱导生成的破骨细胞增多,低、中、高浓度3组破骨细胞数均显著高于空白对照组(P<0.05),中、高浓度组破骨细胞数均显著高于低浓组(P<0.05),高浓度组破骨细胞数亦显著高于中浓组(P<0.05).[结论](1)RAW 264.7是一种较好的破骨前体细胞模型,RAW 264.7诱导形成破骨细胞的方法简便易行,所获得破骨细胞均一性好;(2)人工关节金属磨损颗粒为RAW264.7细胞向具有骨质吸收功能的破骨细胞转化发挥正向作用,而且与混悬液的浓度有量效关系.     

橄榄苦苷对破骨细胞增殖影响的实验研究

目的探讨橄榄苦苷不同药物浓度及不同作用时间对破骨细胞增殖的影响。方法破骨细胞的制备,采用sRANKL与M-CSF诱导小鼠单核细胞RAW264.7细胞获得破骨细胞。设置实验组:4组分别加入400μg/mL、200μg/mL、100μg/mL、50μg/mL橄榄苦苷,另设空白对照组。运用抗酒石酸酸性磷酸酶染液试剂盒进行破骨细胞TRAP染色鉴定,并采用Cell Counting Kit法(CCK法)检测应用不同浓度橄榄苦苷及不同作用时间抑制破骨细胞增殖的情况。结果与空白对照组比较,400μg/mL、200μg/mL、100μg/mL橄榄苦苷对破骨细胞的增殖均具有明显抑制作用。当药物作用时间为24 h及72 h时,400μg/mL橄榄苦苷对破骨细胞增殖的抑制作用最强,当药物作用时间为48 h时,200μg/mL橄榄苦苷对破骨细胞增殖的抑制作用最强,差异有统计学意义(P0.05);50μg/mL橄榄苦苷对破骨细胞的增殖无明显抑制作用,差异不具有统计学意义(P0.05)。结论橄榄苦苷可能通过破坏破骨细胞细胞膜的完整性抑制破骨细胞的增殖。     

MAPK信号转导通路与人工关节磨损颗粒诱导骨溶解

人工关节置换术后无菌性松动的重要原因之一为人工关节磨损颗粒诱导的骨溶解。研究显示,磨损颗粒刺激人工关节周围炎性介质及细胞因子活性增加,造成局部破骨细胞生成增加,使得人工关节周围正常骨质被吸收破坏,最终导致骨溶解和无菌性松动。人工关节周围炎性介质及细胞因子通过信号转导通路介导破骨细胞成熟分化。该文就丝裂原活化蛋白激酶(MAPK)信号转导通路可能参与破骨细胞调控,以及与人工关节磨损颗粒诱导骨溶解的关系的研究作一综述。     

依那西普对磨屑诱导骨溶解影响的实验研究

[目的]检测依那西普（Etanercept，Enbrel）对钛颗粒刺激巨噬细胞（macrophages，MФ）分泌肿瘤坏死因子α（tumor necrosis factor-α，TNF-α）、白介素1（interleukin-1，IL-1）、白介素6（interleukin-6，IL-6）的影响，探讨依那西普防治人工关节无菌性松动的可能性。[方法]分离、培养小鼠腹腔巨噬细胞，24h后分为5组。A组：仅为MФ；B组：MФ＋钛颗粒；C组：MФ＋钛颗粒＋依那西普（10ng／m1）；D组：MФ＋钛颗粒＋依那西普（100ng／ml）；E组：MФ＋钛颗粒＋依那西普（1000ng／ml）。培养18h后，用酶联免疫法（ELISA）检测细胞培养上清液中TNF-α、IL-1、IL-6的含量。[结果]B组TNF-α、IL-1、IL-6含量明显高于A、D、E组（P〈0．001），E组TNF-α、IL-1、IL-6的含量明显低于B组、C组（P〈0．001，E组和D组间无统计学意义（P〉0．05）。[结论]钛颗粒可以刺激MФ分泌大量的TNF-α、IL-1、IL-6，依那西普能够呈剂量依赖型地有效抑制钛颗粒诱导的MФ分泌TNF-α、IL-1、IL-6，有望成为预防人工关节无菌性松动的药物。     

RANK/RANKL/OPG系统与人工关节无菌性松动

人工关节置换术是临床上治疗各种终末期关节疾病最常用的有效方法,但人工关节无菌性松动常影响其远期疗效。目前多数学者认为人工关节周围破骨细胞介导的骨吸收,是导致人工关节松动的主要原因。近年许多研究表明核因子-κB受体活化因子（RANK）/RANK配体（RANKL）/骨保护素（OPG）系统与人工关节无菌性松动有密切关系,在体内受多种促骨激素和细胞因子的直接或间接作用,调控RANKL-OPG比值,介导破骨细胞分化、活化和凋亡,从而影响骨代谢。该文就RANK/RANKL/OPG系统功能、磨损颗粒对其作用及其基因治疗研究进展作一综述。     

辛伐他汀对钛颗粒刺激人单核细胞形成破骨细胞的影响

目的研究体外辛伐他汀对钛颗粒刺激单核细胞形成破骨细胞的影响,探讨辛伐他汀防治人工关节无菌性松动的可能性。方法体外分离培养人外周血单个核细胞并分成5组,A组为钛颗粒刺激组（单核细胞和磨屑混合培养）,B组为10^-5mol／L辛伐他汀组（单核细胞、磨屑混合培养＋10^-5mol／L辛伐他汀）,C组为10^-6mol／L辛伐他汀组（单核细胞、磨屑混合培养＋10^-6mol／L辛伐他汀）,D组为10^-7mol／L辛伐他汀组（单核细胞、磨屑混合培养＋10^-7mol／L辛伐他汀）,E组为单核细胞组。各组细胞培养24h后取上清液,用ELISA法检测上清液中肿瘤坏死因子（TNF-α）、单核细胞趋化蛋白-1（MCP-1）的含量。分别培养10d、18d后进行TRAP染色阳性细胞计数,采用扫描电镜检测骨磨片的吸收陷窝,观察钛颗粒对破骨细胞形成的影响。结果磨屑刺激单个核细胞分泌溶骨因子,辛伐他汀抑制磨损颗粒刺激单核／巨噬细胞分泌TNF-α及MCP-1;且破骨细胞数明显减少,骨吸收陷窝数减少,与钛颗粒组刺激组比较,差异均有统计学意义（P〈0．05）。结论辛伐他汀通过抑制TNF-α、MCP-1的释放而有效防止磨屑诱导的骨溶解,有望成为防治人工关节无菌性松动的一种有潜力的药物。     

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.     

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.     

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.