氯胺酮麻醉引起c-fos基因在大鼠大脑皮质的表达

目的检测氯胺酮对大鼠大脑皮质c-fos基因表达的影响,探讨氯胺酮对中枢神经系统作用的机制.方法将48只Wistar大鼠随机分为六组,即生理盐水组,给药后15、30、60、120和180 min组,每组8只.腹腔注射氯胺酮100 mg/kg后,分别于给药前(生理盐水组)和给药后15、30、60、120、180min提取大脑皮质总RNA量,经过逆转录多聚酶链反应,扩增出cDNA产物.用成像分析系统计算曲线下面积,与内参照比较表示各时点的c-fox mRNA水平.免疫组织化学方法检测各组Fos蛋白阳性细胞率.结果氯胺酮注射后引起大脑皮质c-fos mRNA表达增高,其高峰在30～60min之间,3 h后回至基线水平,且与行为学变化呈时间相关性.氯胺酮注射后1 h引起大脑皮质Fos阳性细胞率明显增高(P＜0.05).结论c-fos基因参与了氯胺酮所致精神症状的分子基因机制.     

异丙酚对氯胺酮诱导的热休克蛋白70基因在大鼠后扣带回皮质区表达的影响

目的：观察异丙酚对氯胺酮诱导的热休克蛋白70（HSP70）基因在大鼠后扣带回皮质区表达的影响，探讨异丙酚抑制氯胺酮所致精神症状和神经损害的机制。方法：雄性Wistar大鼠30只，随机分为生理盐水5ml组、氯胺酮100mg/kg组、异丙酚100mg/kg组、异丙酚50mg/kg-氯胺酮100mg/kg组、异丙酚100mg/kg-氯胺酮100mg/kg组。于用药后24h，大鼠断头取脑，用半定量RT－PCR技术和免疫组织化学方法检测各组HSP 70 mRNA和HSP 70蛋白在大鼠后扣带回皮质区的表达。结果：氯胺酮可明显诱导HSP 70 mRNA与HSP 70蛋白在大鼠后扣带回皮质区的表达；异丙酚自身不能诱导HSP 70基因的表达；预先给予异丙酚可显著抑制氯胺酮诱导的HSP 70 mRNA和HSP 70蛋白在这一区域的表达，且抑制效应呈剂量依赖性。结论：异丙酚可抑制氯胺酮的HSP 70 mRNA与HSP 70蛋白在大鼠后扣带回皮质区的表达，这可能是其预防或减轻氯胺酮所致精神症状和神经损害的机制之一。     

咪唑安定对氯胺酮诱导的c-fos基因在大鼠后扣带回皮质区表达的影响

目的 观察咪唑安定对氯胺酮诱导的c-fos基因在大鼠后扣带回皮质区表达的影响，探讨咪唑安定预防或减轻氯胺酮所致精神症状及神经损害的机制。方法 雄性Wistar大鼠30只，随机分为生理盐水5ml组、咪唑安定15mg／kg组、氯胺酮100mg／kg组、咪唑安定15mg／kg加氯胺酮100mg／kg组、氯胺酮100mg／kg加咪唑安定15mg／kg组。咪唑安定与氯胺酮两药间隔15min给药，所用药物均由腹腔注射。各组动物于用药后2h开胸经心脏灌流脑固定，用免疫组织化学方法检测后扣带回皮质区c-fos蛋白的表达，用彩色病理图像分析系统测定c-fos阳性细胞的百分率和阳性细胞的密度。结果氯胺酮可明显诱导c-fos蛋白在大鼠后扣带回皮质区的表达；咪唑安定自身不能诱导c-fos的表达；咪唑安定预处理可显著抑制氯胺酮诱导的c-fos在这一区域的表达；先用氯胺酮后给予咪唑安定仅能部分抑制c-fos的表达。结论 咪唑安定预处理可抑制氯胺酮诱导的c-fos基因在大鼠后扣带回皮质区的表达，这可能是其预防或减轻氯胺酮所致精神症状和神经损害的机制之一。     

异丙酚抑制福尔马林致痛诱导c-fos基因在大鼠脊髓内的表达

目的研究异丙酚在脊髓水平是否有镇痛作用.方法SD大鼠15只,随机分为三组对照组、芬太尼组、异丙酚组,分别腹腔注射0.9%生理盐水,0.1mg/kg芬太尼或100mg/kg异丙酚,2min后,向大鼠右侧后肢跖部皮下注射福尔马林,1h后,用Fos免疫组织化学方法观察脊髓内c-fos基因的表达.结果福尔马林仅诱导Fos在同侧脊髓表达,预注芬太尼或异丙酚明显抑制Fos的表达,Fos免疫反应阳性神经元(FLIN)数量分别降低了57.8%、36.3%(P＜0.01),且芬太尼的抑制作用强于异丙酚(P＜0.01).结论睡眠剂量的异丙酚在脊髓水平有镇痛作用,但作用比芬太尼弱.     

异丙酚对应激大鼠脑组织不同区域c-fos mRNA表达的影响

目的检测异丙酚对应激大鼠脑内c-fos基因表达的影响.方法21只Wistar大鼠随机分为3组,每组7只.对照组(C组)和单纯电刺激组(S组)腹腔分别注射生理盐水2ml,异丙酚处理组(P组)腹腔注入异丙酚100mg@kg-1.注药5min后接通电刺激仪,C组不通电,其余两组均以2mA直流电行足底电击.刺激后30min断头,取躯干血8ml,并提取大脑皮质、下丘脑和海马组织总RNA,经逆转录多聚酶链反应得到cDNA扩增产物.用c-fos基因扩增产物的密度与γ-actm基因扩增产物的密度比值,表示c-fosmRNA的表达水平.采用放免法测定血浆促肾上腺皮质激素和皮质醇浓度.结果S组脑组织c-fos mRNA表达水平和血浆促肾上腺皮质激素浓度较对照组明显升高(P＜0.01);P组血浆促肾上腺皮质激素、皮质醇浓度和海马、大脑皮质、下丘脑c-fos mRNA表达较S组显著降低(P＜0.01),只有下丘脑组织c-fos基因表达回复基线水平.结论c-fos参与了应激反应的分子基因调控机制;异丙酚抑制了脑内应激反应c-fos基因的表达,其程度有部位性差异.     

氯胺酮麻醉及脾切除术对幼年大鼠学习记忆的影响

目的观察氯胺酮麻醉及脾切除术对幼年大鼠学习记忆的影响。方法健康幼年雄性SD大鼠30只,15日龄,体重29~31g,随机分为三组:生理盐水组(S组)、氯胺酮组(K组)、氯胺酮+脾切除组(KS组),三组大鼠腹腔分别给予等容量生理盐水0.3 ml、氯胺酮100 mg/kg(10mg/ml)、氯胺酮100mg/kg(10mg/ml),KS组大鼠氯胺酮麻醉后行脾切除。2周后三组大鼠进行Morris水迷宫实验,记录逃避潜伏期、Ⅱ象限穿越次数及Ⅱ象限游泳时间。水迷宫实验结束后杀死大鼠,采用ELISA法检测大鼠海马组织谷氨酸(Glu)和γ-氨基丁酸(GABA)含量。结果与S组比较,K组前3d和KS组前4d逃避潜伏期明显延长(P0.01),K组和KS组Ⅱ象限穿越次数明显减少,Ⅱ象限游泳时间明显缩短(P0.05);与K组比较,KS组逃避潜伏期明显延长,Ⅱ象限穿越次数明显减少,Ⅱ象限游泳时间明显缩短(P0.01)。与S组比较,K组和KS组Glu含量明显降低,Glu/GABA明显减小(P0.05),KS组GABA含量明显升高(P0.05);与K组比较,KS组Glu含量明显降低,Glu/GABA明显减小(P0.05)。结论氯胺酮麻醉及脾切除均能损伤幼年大鼠的学习记忆功能,且其记忆功能受损与海马区Glu含量及Glu/GABA下调有关。氯胺酮对幼年大鼠学习能力的损害只是暂时的,脾切除能延长并进一步损害幼年大鼠的学习能力。     

基于脑组织转录组整合分析探索大鼠氯胺酮的麻醉机制

目的:通过观察氯胺酮麻醉对大鼠大脑皮质转录组表达的影响,探讨其可能的麻醉机制。方法:选择5~6周龄雄性SD大鼠6只,采用完全随机法分为氯胺酮组（KET组）和对照组（Ctrl组）,每组3只。分别腹腔注射麻醉剂量氯胺酮（50 mg/kg）或等体积生理盐水后30 min,提取大脑皮质进行mRNA测序（mRNA sequenc...     

孕早期氯胺酮麻醉对子代大鼠海马c-fos mRNA和c-jun mRNA表达的影响

目的 探讨孕早期氯胺酮麻醉对子代大鼠海马c-fos mRNA和c-jun mRNA表达的影响.方法 孕5～13 d的SD大鼠30只,体重250～300 g,随机分为2组(n=15):对照组(C组)和氯胺酮组(K组).K组经尾静脉注射氯胺酮20 mg/kg,随后以130 mg·kg-1·h-1的速率静脉输注2 h;C组以等量生理盐水替代氯胺酮.子代大鼠于出生后20和30 d时测定认知功能,取海马组织,测定c-fosmRNA和c-jun mRNA表达水平并观察超微结构.结果 与C组比较,K组子代大鼠出生后30 d时认知功能测定第2天逃避潜伏期延长(P＜0.05),海马c-fos mRNA和c-jun mRNA的表达水平差异无统计学意义,出生后20 d上述指标差异无统计学意义(P＞0.05).K组海马神经元发生损伤.结论 孕早期氯胺酮麻醉抑制子代大鼠认知功能的机制与海马神经元受损有关,但与海马c-fos mRNA和c-jun mRNA表达无关.     

异丙酚对大鼠脑缺血/再灌注时脑组织c-fos基因表达的影响

目的 观察异丙酚在大鼠脑缺血/再灌注时对脑组织c-fos蛋白及c-fos mRNA表达的影响,从蛋白和分子水平探讨异丙酚脑保护作用的机制。方法 采用Pulsinelli-Brierley四血管闭塞的方法制作急性全脑缺血/再灌注损伤模型。40只大鼠随机分为假手术组、缺血/再灌注对照组和缺血/再灌注异丙酚处理组,后者根据异丙酚剂量又分为C1(50 mg·kg-1)、C2(100 mg·kg-1)和C3(150 mg·kg-1)三个亚组。全脑缺血10 min再灌注60 min时处死大鼠,分别采用免疫组织化学方法和半定量逆转录聚合酶链反应(RT-PCR)技术,对缺血/再灌注后脑内c-fos蛋白及c-fos mRNA在海马组织的表达进行检测。结果 缺血/再灌注后皮层、海马、纹状体及边缘区等脑区均有大量的c-fos阳性蛋白表达,其中对照组呈强阳性表达,假手术组仅有少量c-fos阳性蛋白表达,异丙酚处理组则能明显抑制各脑区c-fos蛋白的表达,尤以海马CA1区最为显著;半定量RT-PCR结果显示,缺血,再灌注后海马组织c-fosmRNA表达较假手术组显著增高,而异丙酚处理组则可明显抑制缺血,再灌注后海马组织c-fos mRNA的异常表达。结论 异丙酚的脑保护作用可能与下调c-fos基因表达有关。     

反复注射异丙酚对新生大鼠认知功能的影响

目的 探讨反复注射异丙酚对新生大鼠认知功能的影响.方法 清洁级SD大鼠24只,7 d龄,12～16 g,雌雄各半,随机分为3组(n=8):对照组(C组)腹腔注射生理盐水7.5 ml/kg,1次/d,连续7 d;单次注射异丙酚组(P1组)腹腔注射生理盐水7.5 ml/kg,1次/d,连续6 d,第7天腹腔注射异丙酚75 mg/kg;反复注射异丙酚组(P2组)腹腔注射异丙酚75 mg/kg,1次/d,连续7 d.异丙酚给药结束后2周时采用水迷宫实验测试学习记忆功能,然后断头处死大鼠,取脑组织,采用高效液相色谱法测定皮层和海马谷氨酸、天冬氨酸、甘氨酸和7.氨基丁酸的含量.结果 与C组和P1组比较,P2组认知功能下降,海马天冬氨酸含量降低,皮层和海马谷氨酸含量降低,谷氨酸/γ-氨基丁酸比值下降(P＜0.05),皮层和海马甘氨酸和γ-氨基丁酸含量差异无统计学意义(P＞0.05).结论 反复注射异丙酚可导致新生大鼠远期认知功能减退,可能与脑内兴奋性氨基酸递质含量的降低有关.     

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.     

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.     

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.