异丙酚对成年大鼠血脑屏障通透性的影响

目的　观察静脉输注不同剂量异丙酚对大鼠血脑屏障 (BBB)通透性的影响。方法　 30只成年大鼠随机分为三组 :对照组 (C组 ,不用全麻药 ,n =6 ) ,异丙酚 70mg·kg-1·h-1组 (P1组 ,静脉注射异丙酚 2 0mg/kg继以静脉输注 5 0mg·kg-1·h-11小时 ,n =12 ) ,异丙酚 12 0mg·kg-1·h-1组 (P2组 ,静脉输注异丙酚 12 0mg·kg-1·h-11小时 ,n =12 )。取脑做EB染色观察、镧醛灌注后电镜观察及HE染色光镜观察。结果　P1、P2组EB染色、HE染色及电镜观察结果与C组相比均无明显差别。结论　本实验结果提示 ,静脉输注产生脑电图爆发抑制剂量的异丙酚 (70mg·kg-1·h-1)及更大剂量(12 0mg·kg-1·h-1) 1小时 ,虽然后者产生明显的循环抑制 ,但两者均未增加大鼠BBB对大分子 (EB 白蛋白 )和小分子 (镧离子 )的通透性 ,对中枢神经系统形态也无明显影响。     

大鼠肝缺血/再灌注后肝细胞凋亡的评价及异丙酚对细胞凋亡的影响

目的 观察大鼠肝脏缺血再灌注后肝窦内皮细胞凋亡及异丙酚对肝脏细胞凋亡的影响。方法 选用健康SD雄性大鼠24只,随机分为三组(n=8):A组,肝脏缺血30 min再灌注6 h,再灌注即刻从股静脉输入生理盐水10ml·kg-1·h-1 60 min;B组,再灌注即刻静脉注射异丙酚20 mg/kg,继之输入5％异丙酚50 mg·kg-1·h-1 h;C组,给予假手术处理,未予缺血,余处理同A组。再灌注6 h后取肝组织标本行病理组织学观察,同时测定血浆ALT活性和肝组织MDA含量的变化。采用DNA琼脂糖凝胶电泳、TUNEL染色观察细胞凋亡的情况。结果与C组相比,A组凋亡的肝细胞和肝窦内皮细胞明显增加,且凋亡的细胞主要是肝窦内皮细胞,肝细胞凋亡和坏死则较少。与A组相比,再灌注6 h B组TUNEL阳性肝细胞和肝窦内皮细胞数明显减少(p<0.01),肝组织DNA片段形成也明显减少。同时,B组肝组织坏死程度、血浆ALT活性和肝组织MDA含量均明显低于A组(JD<0.01)。电镜显示B组肝细胞和肝窦内皮细胞损伤也明显轻于A组。结论 细胞凋亡是再灌注早期肝脏细胞死亡的重要机制,肝窦内皮细胞凋亡是再灌注早期肝脏细胞死亡的主要特征。异丙酚可以减少再灌注后的肝脏细胞凋亡和坏死,其抗氧化作用是其减少再灌注后的肝脏细胞凋亡的机制。     

异丙酚、氯胺酮对哮喘大鼠气道痉挛及气道渗出的作用

目的 观察异丙酚、氯胺酮对抗原诱发哮喘大鼠气道痉挛及气道渗出的影响。方法哮喘大鼠30只随机分为5组:I组,静注生理盐水;Ⅱ组,静注异丙酚50 mg·kg·-1·h-1;Ⅲ组,静注异丙酚100 mg·kg-1·h-1;Ⅳ组,静注氯胺酮50 mg·kg-1·h-1;V组,静注氯胺酮100 mg·kg-1·h-1。30 min后静注伊文氏蓝;5 min后静注卵蛋白激发哮喘发作,并维持30 min。观察气道压、肺系数、肺湿干重比、肺含水量、肺组织伊文氏蓝含量变化。结果异丙酚和氯胺酮能显著缓解卵蛋白激发引起的气道痉挛反应(P<0.05),相同剂量异丙酚和氯胺酮对气道压的影响无显著性差异。异丙酚和氯胺酮均可明显降低大鼠肺系数、肺湿干重比和肺含水量(P<0.05)。静注异丙酚或氯胺酮后,肺组织伊文氏蓝渗出明显减少,与I组比较差异有显著性(P<0.05)。结论 异丙酚和氯胺酮均能缓解抗原诱发哮喘大鼠的气道痉挛,且能明显抑制哮喘大鼠的气道渗出。     

不同剂量异丙酚对大鼠小肠缺血再灌注后肺损伤超微结构的影响

目的 探讨不同临床剂量异丙酚对大鼠小肠缺血再灌注后肺损伤肺组织钙离子含量变化和肺组织超微结构改变的影响及其保护作用。方法 雄性SD大鼠40只,随机分为假手术对照组(Ⅰ组)。小肠缺血再灌注组(Ⅱ组)及分别给予异丙酚4mg·kg-1·h-1、8mg·kg-1·h-1、10mg·kg-1·h-1(Ⅳ、Ⅳ、Ⅴ)5组;制作小肠缺血再灌注模型。实验结束即刻取部分肺组织固定于2.5％戊二醛行透射电镜检查肺组织超微结构,部分肺组织用原子吸收分光光度法测钙离子含量。结果IIR后Ⅱ组、Ⅲ组肺组织钙离子含量明显升高,与Ⅰ组、Ⅳ组、Ⅴ组相比均有非常显著差异(P<0.01),Ⅳ组、Ⅴ组与Ⅰ组相比无统计学差异,同时Ⅱ组、Ⅲ组肺组织钙离子含量相比显著差异(P<0.05)。Ⅱ组肺组织超微结构明显受损,异丙酚用药组肺组织超微结构均明显改善,尤其Ⅳ组、Ⅴ组两组除线粒体结构轻微改变外基本接近正常。结论 钙离子在大鼠小肠缺血再灌注后肺损伤中有重要作用,临床剂量异丙酚可明显降低肺组织钙离子含量,并对肺组织超微结构产生保护作用。     

异丙酚对心肌缺血再灌注兔胃粘膜pH值的影响

目的 观察兔心肌缺血再灌注后胃粘膜pH值(pHi)的变化,并探讨异丙酚对心肌缺血再灌注后兔内脏器官微循环灌注的影响。方法20只健康家兔,麻醉后随机分为生理盐水对照组(A组)及异丙酚组(B组,术中5mg·kg-1·h-1)。于基础状态(T0),心肌缺血60min(T1),再灌注后60min(T2)、90min(T3)和180min(T4)分别记录收缩压(SBP)、舒张压(DBP)、心率(HR)和pHi值。结果 两组动物5个不同时点的HR、SBP、DBP无显著差异(P>0.05)。两组动物缺血及再灌注后HR、SBP、DBP均有显著性下降(P<0.01)。pHi变化:与A组相比,B组动物T3点pHi值较低(P<0.05);组内,两组动物缺血及再灌注后pHi值均有显著性下降(P<0.01)。两组动物收缩压(SBP)及HR与pHi的变化均具有显著意义的相关性。结论 兔心肌缺血再灌注后,pHi持续显著降低,且pHi与血流动力学变化趋势一致,具有显著意义相关性。兔缺血再灌注期间,5mg·km-1·h-1异丙酚持续静注并不能改善胃肠道微循环灌注,甚至有可能加重胃肠道的低灌注及氧合障碍。     

不同剂量丙泊酚持续静注对心内直视手术病人肌钙蛋白Ⅰ的影响

目的　观察不同剂量丙泊酚对心内直视术病人肌钙蛋白 Ⅰ (CTn Ⅰ )的影响 ,寻求丙泊酚抑制心肌缺血再灌注损伤作用合适的剂量。方法　 2 7例心内直视手术患者随机分成A、B、C三组。咪唑安定、丙泊酚、维库溴铵、芬太尼诱导后 ,用微量泵持续输注丙泊酚 ,A组 2mg·kg-1·h-1、B组 5mg·kg-1·h-1、C组 8mg·kg-1·h-1。用化学发光法测定诱导后、停心肺转流 (CPB)即刻、CPB后30、6 0分钟和CPB后 3小时动脉血CTn Ⅰ浓度。结果　三组病人CPB后CTn Ⅰ均显著升高 (P <0 0 1)。组间比较 ,B组CPB后CTn Ⅰ值比A组低 (P <0 0 5和P <0 0 1)。C组和A组间CTn Ⅰ值无统计学差异。结论　心脏手术术中及术后CTn Ⅰ升高提示心肌存在不同程度损伤。术中 5mg·kg-1·h-1丙泊酚持续静注是较为理想的具有心肌保护作用的临床用药剂量     

异丙酚对儿童体外循环血小板功能的影响

目的 探讨异丙酚对儿童体外循环(CPB)期间血小板(Plt)功能的影响。方法将40例CPB下行心脏修补术的先心病儿童随机分为对照组(C组)和异丙酚组(P组)。两组均以芬太尼5μg·kg-1·h-1辅助吸入0.7％异氟醚维持麻醉。P组自诱导至术毕持续泵注异丙酚3 mg·kg-1·h-1持续泵注。两组病儿分别于麻醉前、转流30min、手术结束时、术后24 h取中心静脉血测定血小板a-颗粒膜蛋白(GMP-140)和Plt血栓烷B2(TXB2)浓度,及全血激活凝固时间(ACT)、凝集速率、Plt功能(PF)、快速Plt功能(qPF)值,同时测定各时段的Plt计数。结果 两组GMP-140、TXB2在转流期间显著性升高(P<0.01);Plt计数在转流期间显著性下降(P<0.01);ACT转流期间显著性延长(P<0.01),术后恢复基础水平。PF、qPF转流期间测不出,术后恢复至基础水平。C组和P组之间Plt各观测值相比差异无显著性。结论 持续泵注异丙酚3 mg·k-1·h-1对儿童CPB中的血小板功能无明显影响。     

腺苷与异丙酚预处理对犬心肌缺血再灌注损伤的保护作用

目的探讨腺苷与异丙酚预处理对犬心肌缺血再灌注损伤的保护作用。方法 21只杂种犬,雌雄不拘,随机分为3组(n=7):缺血再灌注组(A组)、异丙酚预处理组(B组)、异丙酚与腺苷联合预处理组(C组)。A组冠状动脉的左前降支结扎60min后松开结扎,再灌注:120min;B组缺血前30min经静脉以5．6mg·kg-1·h-1速率持续泵注异丙酚30min;C组缺血前10min经主动脉根部一次性注入腺苷(10mmol·L-1,10ml),其余处理同B组。记录心脏血液动力学指标,并行节段性室壁运动评分(RWMS)。结果缺血即刻出现了缺血性心电图的变化。与基础值比较,A组缺血期及再灌注期 LVEDP升高,CO、SV、LVEF、CPP、RPP降低,再灌注期MAP降低,HR减慢,B、C组上述缺血再灌注诱导的血液动力学变化减弱,A组缺血期及再灌注期RWMS增加,但B、C组缺血期RWMS低于A组(P< 0．05或0．01)。结论异丙酚预处理对犬心肌缺血再灌注损伤有一定的保护作用,腺苷预处理并未增强其保护作用。     

在小儿整形外科手术中异丙酚与氯胺酮复合静脉麻醉最佳搭配的研究

目的　在小儿整形外科手术中寻找异丙酚与氯胺酮复合静脉麻醉最佳搭配方案。方法　选择 36例外耳再造术患儿 ,随机分为四组 ,各组均用异丙酚和氯胺酮不同搭配比例维持麻醉。观察各组病人的麻醉过程中的血流动力学变化情况和麻醉恢复情况 ,同时记录异丙酚与氯胺酮的平均用量。结果　与第二、三、四组相比 ,第一组的异丙酚与氯胺酮用量多、麻醉恢复拔管时间较长、同时麻醉后出现头晕、复视等并发症发生率也较高 (P <0 0 5 )。第二、三组异丙酚用量无统计学差异 (P >0 0 5 ) ,而氯胺酮用量则有统计学差异 (P <0 0 5 )。第三组血流动力学不稳定 (P <0 0 5 )。结论　在小儿整形外科手术中选用适当搭配比例的异丙酚与氯胺酮 (手术前期用异丙酚 6mg·kg-1·h-1、氯胺酮 1 2mg·kg-1·h-1麻醉维持 ;手术中后期用异丙酚 6mg·kg-1·h-1、氯胺酮 0 8mg·kg-1·h-1维持 ;手术后期用异丙酚 6mg·kg-1·h-1维持并根据病人具体情况逐步减少异丙酚的输注速率 )复合静脉麻醉是一理想而且经济的麻醉方案。     

异丙酚对大鼠肠缺血再灌注后肺损伤的影响

目的探讨异丙酚对大鼠肠缺血再灌注后肺损伤的影响。方法32只成年SD大鼠,随机分为4组（n=8）,缺血再灌注组（I/R组）缺血1 h,再灌注2 h;异丙酚1组（P1组）在缺血前10 min、异丙酚2组（P2组）在再灌注前10min静脉注射异丙酚10mg,kg,然后以10mg·kg^-1·h^-1持续输注,余处理同I/R组;假手术组（C组）不行缺血再灌注及异丙酚输注。所有大鼠在再灌注120 min时处死。光镜下观察肺组织形态学及细胞凋亡;测定肺组织超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量及含水量。结果I/R组光镜下可见大量肺泡塌陷、实变,肺实质水肿及中性粒细胞浸润聚集。与C组比较,I/R组及P2组肺组织细胞凋亡计数增加,I/R组肺组织SOD活性降低,MDA含量升高,含水量升高（P＜0．05或0．01）;与I/R组比较,P1组SOD活性升高,MDA含量降低（P＜0．01）。结论细胞凋亡参与了大鼠肠缺血再灌注后肺损伤的发生,肠缺血前给予异丙酚可明显减轻肠缺血再灌注后肺损伤。     

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.