小鼠胚胎干细胞转基因治疗甲状旁腺功能低下症的实验研究

目的　探讨小鼠胚胎干细胞 (TC 1)转基因治疗甲状旁腺功能低下症 (HPT)。方法包装出重组人甲状旁腺素 (PTH )基因的小鼠干细胞病毒 (MSCV) ,以其感染小鼠ESCs ,检测基因转导效率 ,PTH分泌情况 ;观察体内外分化情况 ,以及注入模型鼠体内各组小鼠血PTH和血钙变化情况。结果　获得滴度为 2× 10 7集落形成单位 (CFU ) /ml的重组逆转录病毒 ,经聚合酶链反应(PCR)扩增未检测到有野生型病毒存在 ,可以安全应用。感染TC 1的效率为 70 % ,每 10 6未分化TC 1每 48h分泌PTH约 10ng。重组有PTH基因的TC 1在体内外均可分化出三胚层组织 ,注入模型鼠体内 ,在观察期间实验组动物未再出现甲旁低表现 ,而且血PTH和血钙均保持在接近正常值范围内。结论　MSCV介导外源PTH基因可高效转导TC 1并持续分泌PTH ;体内外分化实验证明TC 1具有全能性 ,而且内环境并不是决定TC 1分化的唯一因素。经基因转导的TC 1可较好的改善模型鼠的症状 ,是未来细胞移植的一种潜在来源。     

造血干细胞基因治疗甲状旁腺功能低下症的实验研究

目的　探讨造血干细胞基因治疗甲状旁腺功能低下症 (HPT)的实验效果。方法　构建重组甲状旁腺素 (PTH)基因的小鼠干细胞病毒 (MSCV)重组质粒 ,转染PA31 7包装细胞 ,G41 8筛选阳性克隆 ,获得的重组病毒液感染造血干细胞 ,静脉注入HPT小鼠血中 ,检测各组小鼠症状改善情况、血PTH及血钙变化情况。结果　获得滴度为 2× 1 0 7CFU(集落形成单位 ) /ml的分泌人PTH的浓缩病毒悬液 ,1× 1 0 6 个细胞培养 48h时PTH的分泌量为 1 5ng。经聚合酶链反应 (PCR)扩增未检测到有野生型病毒存在 ,可以安全应用。感染造血干细胞输注后 ,实验组动物未再出现HPT临床表现 ,而且血钙及血PTH均可长期保持在接近正常值范围内 ,较单纯注射浓缩病毒悬液具有更好的疗效。结论　获得MSCV PTH重组质粒及高滴度的分泌人PTH的浓缩病毒悬液。整合有PTH基因的造血干细胞输注后达到较长期治愈小鼠HPT ,为进一步HPT的临床基因治疗提供了可靠依据。     

转基因造血干细胞移植治疗小鼠甲状旁腺功能低下症的研究

目的　探讨输注整合有甲状旁腺素(PTH)基因的造血干细胞对甲状旁腺功能低下症的治疗效果。方法　将以pcDNA 3.1 PTH 为模板扩增出的PTH 基因插入到逆转录病毒载体MSCV中,得到含PTH基因的重组质粒,并转染PA317 包装细胞,以抗生素Geneticin筛选阳性克隆,获得重组有PTH基因的浓缩病毒悬液,以其感染人脐血造血干细胞,然后注入甲状旁腺功能低下症模型小鼠血中,术后观察小鼠症状的改善情况、血PTH及血钙浓度变化情况。结果　所获得的重组有PTH基因的浓缩病毒悬液,其病毒滴度为2×107 CFU/ml,PTH的分泌量为15 ng/48 h(106个细胞),未检测到有野生型病毒存在。实验组小鼠接受转染有PTH基因的血干细胞后,症状改善,血PTH及血钙浓度逐渐上升,并维持于接近正常水平;仅接受重组有PTH基因的浓缩病毒悬液的小鼠,短期内血PTH及血钙浓度明显升高,以后则呈缓慢下降趋势,并逐渐出现甲状旁腺功能低下症的表现;只接受造血干细胞移植的小鼠术后20 d左右全部死亡。结论　甲状旁腺功能低下症小鼠接受整合有PTH基因的造血干细胞静脉输注可获得较长期的治疗效果。     

甲状旁腺激素基因治疗甲状旁腺功能低下症

目的观察甲状旁腺激素(PTH)基因和蛋白体外表达情况,并评价其基因治疗甲状旁腺功能低下模型鼠的作用。方法(1)以脂质体将质粒pcDPG分别1次和多次转染293细胞,观察绿色荧光蛋白(GFP)的表达并计算转染率;(2)转染24、48、72和96h后real-ti me定量PCR和Western blot法检测PTH基因与蛋白表达,并活性鉴定;(3)建立甲状旁腺功能低下症模型,将pcDPG质粒多次肌肉注射治疗,监测血钙和PTH值、存活时间及各器官病理变化。结果转染后24h即见GFP表达,72h达高峰,96h开始减少;多次转染后GFP表达率可达90%以上;PTHcD-NA拷贝数转染24h为5×103,72h达最高为8×104,多次转染显著增高(P<0.01);Western blot见48h和72h有PTH蛋白表达,其可对抗甲状旁腺切除小鼠抽搐症状;术后第2天血钙与PTH明显低于术前(P<0.05),pcDPG质粒大、中剂量组连续治疗48h后血钙与PTH值均恢复正常。结论重组PTH基因治疗甲状旁腺功能低下模型鼠有较好的疗效。     

不同剂量的甲状旁腺素对成骨细胞分化的不同作用的实验研究

目的探讨不同剂量的甲状旁腺素(PTH)对成骨细胞分化过程的影响。方法培养MC3T3-E1成骨前体细胞,给与不同浓度的PTH处理细胞,real-time PCR方法,检测细胞内成骨因子基因mRNA的表达;碱性磷酸酶(ALP)染色方法,检测细胞内ALP的分泌;Alizarin Red染色方法,检测细胞内成骨钙化作用。结果 1 nmol/L浓度的PTH和10 nmol/L浓度的PTH都具有明显的促进成骨细胞分化的作用,以10 nmol/L浓度的PTH的作用更强。100 nmol/L较高浓度的PTH没有明显促进成骨细胞分化的作用。结论不同剂量的PTH对成骨细胞的分化作用,具有不同的影响。     

甲状旁腺素的生物学研究与成骨作用

甲状旁腺素(PTH)是由甲状旁腺主细胞合成分泌的、含有84个氨基酸的碱性单链多肽,是调节血钙、磷水平的主要激素之一,可促使血钙水平升高,血磷水平下降。PTH可精细调节骨的合成、分解代谢,对成骨细胞和破骨细胞的分化、成熟、凋亡发挥重要作用。本文综述了PTH的化学结构、生理作用、生物学研究成果及PTH的临床应用。PTH对Ⅰ型骨质疏松(绝经后骨质疏松症)、Ⅱ型骨质疏松(老年骨质疏松症)、雌激素缺乏的年轻妇女及糖皮质激素所致的骨质疏松症均有治疗作用,能显著升高骨密度,并能降低患者骨质疏松性骨折发生率,加速骨折愈合。甲状旁腺素在临床骨质疏松治疗、骨质疏松性骨折的治疗中都具有重要的应用价值。     

病毒白细胞介素-10转基因在造血干细胞中的表达

目的　观察逆转录病毒转病毒白细胞介素 10 (vIL 10 )基因在体内的表达。方法　用MSCVneo vIL 10重组体在体外转导CBA (H 2 K)小鼠的造血干细胞 (HSCs) ,给经致死照射(90 0rads)的 2 0只同基因CBA(H 2 K)小鼠注入经MSCVneo vIL 10转染的HSCs ,2× 10 6HSCs/只。酶联免疫吸附测定 (ELISA)、逆转录 聚合酶链反应 (RT PCR )、Westernblot分析vIL 10的表达。结果　移植MSCVneo vIL 10转染HSCs的 2 0只小鼠 ,移植后 8周用ELISA检测 ,其中 15只小鼠血清的vIL 10浓度为 :2 70～ 13 40ng/L ,5只小鼠血清的vIL 10为阴性。 12周后有 2只小鼠vIL 10测不出 ,13只小鼠长时间表达vIL 10达 6个月。对照组小鼠血清vIL 10均为阴性。RT PCR和Westernblot证实小鼠的器官均有vIL 10的mRNA和蛋白的表达。结论　逆转录病毒能有效地将vIL 10基因导入造血干细胞并在体内长时间表达。     

人IL-10逆转录病毒载体的构建及对大鼠原位肝移植存活期的影响

目的　探讨人白细胞介素 10 (hIL 10 )逆转录病毒载体的构建及对大鼠原位肝移植存活期的影响。方法　将hIL 10克隆基因片断 ,经双酶切后定向插入到逆转录病毒载体 (MSCV)中 ,用脂质体法转染PT6 7包装细胞 ,以G418筛选阳性克隆。将Wistar对SD大鼠原位肝移植模型分三组 ,组Ⅰ为空白对照组 ,组Ⅱ为MSCV空载体灌洗组 ,组Ⅲ为MSCV hIL 10灌洗组。观察大鼠存活期及肝脏功能变化。结果　hIL 10基因片断插入到MSCV载体中经转染包装后得到 2× 10 7CFU ml的分泌hIL 10的病毒悬液 ,hIL 10分泌量为 12 2 0ng 10 6 细胞 2 4h。组Ⅲ与组Ⅰ、组Ⅱ比 ,大鼠存活期明显延长 (P <0 0 1) ,肝脏功能无明显差异。结论　获得MSCV hIL 10重组质粒 ,获得高滴度的分泌hIL 10的病毒悬液 ,hIL 10的表达可延长大鼠原位肝移植的存活期。     

异基因骨髓间充质干细胞移植治疗小鼠前列腺癌的实验研究

目的观察非清髓性异基因骨髓间充质干细胞移植对小鼠前列腺移植瘤的治疗效果。方法应用全骨髓培养法培养BALB/c小鼠骨髓间充质干细胞,通过流式细胞术检测第四代细胞中CD44阳性细胞率,并通过油红染色鉴定由骨髓间充质干细胞分化的脂肪细胞。应用C57小鼠源性前列腺癌株RM-1(2×10~6/只)制成C57BL小鼠皮下移植瘤模型,分为对照组和异基因骨髓间充质干细胞移植组,每组10只。应用FC方案(氟达拉滨30mg/m~2,-d~(1-5);环磷酰胺300mg/m~2,-d~(1-3))对非对照组小鼠进行非清髓性预处理。异基因干细胞移植组小鼠经尾静脉注入骨髓间充质干细胞1×10~6个/只。记录并比较两组小鼠的肿瘤体积及生存时间。结果全骨髓培养法培养的第四代细胞中CD44阳性率为84.29%,油红染色证实由骨髓间充质干细胞自然分化的脂肪细胞存在。与对照组相比,异基因骨髓间充质干细胞移植显著的抑制了小鼠前列腺癌的生长(P=0.047),并明显延长了异基因骨髓间充质干细胞移植组小鼠的生存时间(P=0.00001)。结论异基因骨髓间充质干细胞移植显著的抑制了小鼠前列腺癌的生长,延长了受体小鼠的生存时间,预示了将骨髓间充质干细胞作为抑癌基因载体的良好前景。     

甲状腺术中甲状旁腺原位损伤类型对甲状旁腺功能的影响

目的 通过模拟甲状腺全切除术中甲状旁腺不同类型的原位损伤情况建立动物模型,研究不同程度的甲状旁腺原位损伤对术后甲状旁腺功能恢复的影响.方法 以实验家兔为研究对象,随机分为A、B、C、D四组,每组8只,A组(假手术组):单纯暴露、探查甲状腺、甲状旁腺;B组(血供损伤组):双侧甲状腺全切除+双侧下甲状旁腺血供损伤保留被膜;C组(被膜损伤组)双侧甲状腺全切除+双侧下甲状旁腺被膜损伤保留血供;D组(复合损伤组)双侧甲状旁腺全切除+双侧下甲状旁腺被膜及血供的复合损伤.术前1d,术后第1天、第3天、第5天、第7天监测血钙、血PTH,术后第7天切取双侧下甲状旁腺行苏木精-伊红染色,观察甲状旁腺组织的存活及病理损害.结果 (1)各组动物术前血钙、血PTH差异无统计学意义(P＞0.05);(2)A组术后血钙下降,但在第5天恢复至术前水平(P＞0.05);B、C组术后血钙明显下降(P＜0.05),以术后第1天最低,逐渐恢复,但C组恢复较B组快(P＜0.05);D组术后血钙持续下降;(3)A组术后血PTH下降,但在第7天恢复至术前水平(P＞0.05);B、C组术后血PTH明显下降(P＜0.05),以术后1d最低,逐渐恢复,但3d后C组恢复较B组快(P＜0.05);D组术后血PTH持续下降;(4)病理结果:A组甲状旁腺以主细胞为主,少量空泡性改变(5％～10％);B组甲状旁腺出血、坏死(40％ ～50％),部分细胞空泡变性(30％ ～ 40％),中心伴纤维化,周边可见炎性肉芽肿及增生的甲状旁腺组织;C组甲状旁腺出血(10％ ～20％),部分细胞空泡变性(10％ ～ 20％);D组甲状旁腺坏死,几乎无正常甲状旁腺组织,明显纤维化,残存的甲状旁腺组织较少呈散在分布.结论 (1)甲状腺术中甲状旁腺原位损伤的类型影响术后甲状旁腺功能的恢复,其中甲状旁腺血供和被膜的复合损伤最严重,甲状旁腺缺血坏死,功能不能恢复;单纯血供损伤,部分能恢复功能;带血管蒂的甲状旁腺原位保留能较快的恢复功能;(2)对于甲状腺术中严重血供及被膜损伤,甚至游离的甲状旁腺应立即自体移植.     

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.     

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.     

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.