脊柱侧凸椎旁肌肌纤维群化现象的研究

目的对椎旁肌肌纤维群化现象与青少年特发性脊柱侧凸(adolescent id iopath ic scoliosis,AIS)的发生、发展之间的关系进行研究。方法本实验分三组,AIS组:20例,平均年龄15.3岁,平均Cobb角56.8°。顶椎位于T7~12。其中Cobb角>50°11例,Cobb角≤50°9例。先天性脊柱侧凸(congen ital scoliosis,CS)组:11例,平均年龄13.9岁,平均Cobb角66.7,°顶椎位于T7~12。对照组:取10例非脊柱侧凸病例作为对照。AIS和CS组取顶椎区两侧椎旁肌,对照组取非病变区两侧椎旁肌行病理分析。结果AIS和CS组均存在凸侧椎旁肌Ⅰ型肌纤维群化现象,对照组未观察到肌纤维群化现象。CS组的肌纤维群化程度显著高于AIS组(P<0.05),AIS组中Cobb角>50°的患者肌纤维群化程度显著高于Cobb角≤50°的患者(P<0.05)。结论脊柱侧凸凸侧椎旁肌Ⅰ型肌纤维群化现象系继发性改变,且与侧凸的严重性呈正相关。     

特发性脊柱侧凸患者两侧椎旁肌横截面积的CT测量

目的:观察特发性脊柱侧凸(IS)患者凸、凹侧椎旁肌横截面积是否存在差异,探讨椎旁肌改变与脊柱侧凸的关系.方法:IS患者31例,女20例,男11例,年龄12～18岁,Cobb角范围28°～76°,平均53°±12°,在CT片上测量上终椎、顶椎、下终椎双侧椎旁肌横截面积.同龄非脊柱畸形患者(对照组)20例,女8例,男12例,年龄5～15岁,在CT片上测量T8、T10双侧椎旁肌横截面积.比较两组双侧椎旁肌的横截面积.结果:IS患者上终椎、顶椎、下终椎凸侧椎旁肌横截面积均大于凹侧,差异有统计学意义(P<0.05);凸/凹侧椎旁肌横截面积比值顶椎>上终椎>下终椎;Cobb角>50°和<50°患者顶椎水平凸,凹侧椎旁肌横截面积比值无统计学意义(P>0.05),顶椎水平凸/凹侧椎旁肌横截面积比值与Cobb角无显著相关性.对照组双侧椎旁肌横截面积差异无统计学意义(P>0.05),左/右侧椎旁肌横截面积比值亦无统计学意义(P>0.05).结论:特发性脊柱侧凸患者双侧椎旁肌发育不对称,凸侧椎旁肌横截面积大于凹侧,且在顶椎水平差异最大,但顶椎水平椎旁肌横截面积凸,凹侧比值与Cobb角无明显相关性.     

特发性脊柱侧凸患者两侧椎旁肌中肌梭与运动终板病理学变化的对比研究

目的：对青少年特发性脊柱侧凸（AIS）患者两侧椎旁肌中肌梭与运动终板的病理学变化进行对比研究，探讨其与脊柱侧凸病因学可能存在的关系。方法：选取手术治疗的脊柱病变患者共41例．分3组．其中AIS组20例，平均年龄15．3岁，平均Cobb角56．8^o，顶椎位于T7～T12；先天性脊柱侧凸（CS）组ll例。平均年龄13．9岁，平均Cobb角66．7^o，顶椎位于T7～T12；对照组10例，均为非脊柱侧凸病例，其中l例腰椎滑脱、l例腰椎管肿瘤、2例Scheuermann’s病、6例腰椎间盘突出症，平均年龄17．3岁。经患者知情同意，所有病例均于术中取材，AIS组和CS组取顶椎区两侧椎旁肌，对照组取非病变区两侧椎旁肌。标本分别行HE染色和非特异性酯酶（ANAE）染色，对3组病例两侧椎旁肌中肌梭的形态结构、梭内肌纤维数目、平均横截面积以及运动终板的类型进行比较。结果：AIS组患者两侧椎旁肌标本共发现19个肌梭，CS组患者两侧椎旁肌标本共发现13个肌梭，对照组两侧椎旁肌标本共发现5个肌梭。AIS和CS组患者凸侧椎旁肌肌梭内的肌纤维数目及平均横截面积显著大于凹侧椎旁肌（P〈0．05）。AIS和CS组凹侧椎旁肌哟型终板数目和病变终板数目均显著多于凸侧椎旁肌（Pl〈0．05）。对照组两侧椎旁肌哟型终板数目和病变终板数目无显著差异（P＞0．05）。结论：AIS患者两侧椎旁肌中肌梭的形态结构和运动终板的类型存在差异，这种差异可能是脊柱侧凸的继发性改变。     

脊柱侧凸椎旁肌肌纤维不对称性分布的研究

目的　对特发性脊柱侧凸两侧椎旁肌肌纤维分布进行比较 ,并探讨其与脊柱侧凸病因学可能存在的关系。方法　本实验分三组 ,特发性脊柱侧凸组 :2 0例 ,平均年龄 15 .3岁 ,平均Cobb角为 5 6 .8° ,顶椎位于T7～12 。其中Cobb角 >5 0° 11例 ,Cobb角≤ 5 0° 9例。先天性脊柱侧凸组 :11例 ,平均年龄 13.9岁 ,平均Cobb角为 6 6 .7° ,顶椎位于T7～12 。对照组 :取 10例非脊柱侧凸病例作为对照。特发性脊柱侧凸和先天性脊柱侧凸组取顶椎区两侧椎旁肌 ,对照组取非病变区两侧椎旁肌 ,进行病理分析。结果　特发性脊柱侧凸和先天性脊柱侧凸组凸侧椎旁肌Ⅰ型肌纤维含量和横截面积均显著大于凹侧 (P <0 .0 5 ) ,对照组两侧无显著差异 (P >0 .0 5 ) ,特发性脊柱侧凸组中Cobb角 >5 0°的病例凸侧Ⅰ型肌纤维含量显著高于Cobb角≤ 5 0°的病例 (P <0 .0 5 )。结论　脊柱侧凸两侧椎旁肌肌纤维分布不对称系继发性改变     

脊髓空洞源性脊柱侧凸椎旁肌超微结构的比较观察

目的 比较观察脊髓空洞源性脊柱侧凸患者椎旁肌超微结构病理改变的特征,探讨脊柱侧凸的发生机制。方法全部病例分为三组：脊髓空洞源性脊柱侧凸（SS）组12例,青少年特发性脊柱侧凸（AIS）组5例,非脊柱侧凸（NS）组2例。术中切取患者两侧骶棘肌组织,分别进行光镜和电镜观察。结果 SS组有2例患者出现小群性肌萎缩。1例发生周围神经脱髓鞘,7例可见靶纤维或靶样纤维。与AIS组相比,SS组患者骶棘肌的超微结构明显异常。表现为肌质网普遍扩张,线粒体肿胀形成髓鞘样结构,胞质内散在脂滴增多,肌原纤维间糖原聚集,糖原湖形成。结论脊髓空洞源性脊柱侧凸患者存在椎旁肌失神经支配现象,椎旁肌超徽结构的异常以胞浆中细胞器为主,两肌原纤维的病变较轻。SS患者椎旁肌超微结构的异常程度明显比AIS严重,这可能与其椎旁肌发生失神经支配有关。     

乙酰胆碱受体亚基在脊髓空洞源性脊柱侧凸患者椎旁肌的表达及其意义

目的：测定神经肌肉接头处乙酰胆碱受体分子五聚体中亚基的表达,判断脊髓空洞源性脊柱侧凸患者椎旁肌是否存在失神经支配.方法：将2003年3月～2004年10月行手术治疗的40例患者分为3组：脊髓空洞源性脊柱侧凸（空洞-侧凸）组20例,青少年特发性脊柱侧凸（AIS）组10例,非脊柱侧凸组10例.切取脊柱两侧椎旁肌中的部分骶棘肌组织,RT-PCR法检测其神经肌肉接头处乙酰胆碱受体α和γ亚基的表达情况.结果：所有病例均有α亚基表达.空洞-侧凸组中13例（65%）出现γ亚基阳性条带,其中侧凸凸侧γ亚基表达阳性率为55%（11/20）,凹侧为40%（8/20）;AIS组脊柱凹、凸两侧椎旁肌的γ亚基表达均为阴性;非脊柱侧凸组仅1例左侧椎旁肌检测到γ亚基阳性条带,其余为阴性.结论：脊髓空洞源性脊柱侧凸患者椎旁肌神经肌肉接头处乙酰胆碱受体γ亚基的异常表达,提示其椎旁肌失神经支配的存在,可能是该类脊柱侧凸发生的始动因素之一.     

脊柱侧凸胸段椎旁肌的肌纤维类型

特发性脊柱侧凸是一种原因不明的畸形,本文通过对脊柱侧凸胸段竖肌的组织化学研究证实:凸侧具有很大百分比的Ⅰ类肌纤维。Ⅰ类肌纤维的氧化能力比Ⅱ类肌纤维高,因而更能抗疲劳,其主要作用是维持躯体姿势的紧张性活动。本文探讨的是:青少年型特发性脊柱侧凸(AIS)椎旁肌中的肌纤维类型分布,     

特发性脊柱侧凸患者椎旁肌中胶原的表达及意义

目的:通过比较特发性脊柱侧凸(idiopathic scoliosis,IS)、先天性脊柱侧凸(congenital scoliosis,CS)顶椎凹凸侧椎旁肌和无脊柱侧凸患者椎旁肌的组织形态学改变及胶原蛋白表达的变化,探讨椎旁肌在IS发展中的作用机制。方法:分别取IS患者(A组)、CS患者(B组)顶椎凹凸两侧及无脊柱侧凸患者(对照组,C组)的椎旁肌,光镜和电镜下观察其组织学形态学改变;应用Masson三色染色法显示胶原蛋白的表达,图像分析系统测量各组胶原的阳性表达面积百分比;对各组结果采用SPSS13.0软件进行统计学处理。应用免疫组织化学方法对Ⅰ型和Ⅲ型胶原染色,观察其在各组的表达情况。结果:光镜和电镜下均显示A、B组凹侧椎旁肌形态明显异常,胶原表达增强、分布紊乱;A、B组凸侧椎旁肌及C组未见明显异常。A、B组凹侧椎旁肌中阳性胶原面积的百分比分别为0.255±0.036和0.253±0.023,明显高于凸侧(A、B组分别为0.057±0.006和0.055±0.002)及C组(0.056±0.004),差异有显著性(P<0.05)。免疫组织化学染色示A、B两组凹侧椎旁肌中Ⅰ型、Ⅲ型胶原表达无明显差异,而在凸侧椎旁肌中以Ⅰ型胶原阳性者为主。结论:IS患者凹侧椎旁肌形态明显异常,胶原表达增强且分布紊乱,其变化可能为IS的继发性改变。     

青少年特发性脊柱侧凸患者椎旁肌中钙调蛋白的表达及临床意义

目的:探讨青少年特发性脊柱侧凸(AIS)患者椎旁肌钙调蛋白的表达及其对肌浆网钙离子通道的影响。方法:AIS患者共30例,Cobb角40°～100°,其中Cobb角≥50°者15例(A组),Cobb角<50°者15例(B组);对照组(C组)5例患者均为非脊柱侧凸病例。于手术中取A、B组患者顶椎区两侧椎旁肌、取C组患者非病变部位两侧椎旁肌作为标本进行分子生物学分析,采用RT-PCR方法检测所有标本钙调蛋白和肌浆网钙离子通道的mRNA表达量。结果:A、B组患者椎旁肌钙调蛋白mRNA的表达比C组高(P<0.05),并且A组患者凸侧椎旁肌钙调蛋白mRNA显著高于凹侧(P<0.05),而B组患者其凹凸侧钙调蛋白mRNA没有显著性差异(P>0.05);C组椎旁肌肌浆网钙离子通道mRNA的表达比A组患者高(P<0.05),A组患者凸侧椎旁肌肌浆网钙离子通道mRNA显著低于凹侧(P<0.05),而B组患者其凹凸侧肌浆网钙离子通道mRNA没有显著性差异。结论:钙调蛋白mRNA在AIS患者椎旁肌中的表达较无脊柱侧凸者高,而且其表达随着侧凸程度的加重而增高;AIS患者椎旁肌肌浆网钙离子通道表达有异常,钙调蛋白的过度表达可能导致了钙离子通道的损伤。     

特发性脊柱侧凸两侧椎旁肌的影像学差异及其临床意义

目的研究特发性脊柱侧凸两侧椎旁肌的影像学变化,并探讨其与特发性脊柱侧凸病因的关系。方法共分三组:特发性脊柱侧凸组39例,男6例,女33例,平均年龄(14.0±1.1)岁。Cobb角40°～108°,平均55.8°±16.7°。KingⅡ型20例,KingⅢ型19例,顶椎位于T6￣T11。其中Cobb角>50°者18例,Cobb角≤50°者21例。先天性脊柱侧凸组25例,男12例,女13例,平均年龄(13.6±1.6)岁。Cobb角40°～155°,平均78.9°±32.1°,顶椎位于T5～T12。12例非脊柱侧凸病例作为对照组,男4例,女8例,平均年龄(23.2±5.8)岁。脊柱侧凸病例取顶椎区水平位MR像,对照组取上位腰椎非病变区水平位MR像,测量两侧椎旁肌的面积和Balance序列平均信号值。结果特发性脊柱侧凸和先天性脊柱侧凸组顶椎区凹侧椎旁肌平均横截面积明显小于凸侧(P<0.05),MRIBalance序列平均信号值明显高于凸侧(P<0.05)。对照组两侧差异无统计学意义(P>0.05)。特发性脊柱侧凸组中Cobb角>50°的病例顶椎区凹凸侧椎旁肌平均横截面积比值和平均信号比值与Cobb角≤50°的病例相比,差异无统计学意义(P>0.05)。结论特发性脊柱侧凸患者两侧椎旁肌存在影像学差异,这种差异可能系脊柱侧凸的继发性改变,且对判断脊柱侧凸的进展性具有潜在的临床意义。     

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.