X线影像导航系统辅助关节镜下前交叉韧带重建术

目的 探讨X线影像导航系统辅助关节镜下前交叉韧带重建手术的可行性和隧道位置的精确性。方法 2005年12月至2006年2月共行X线影像导航系统辅助前交叉韧带重建手术30例（导航手术组）,同期使用传统关节镜手术技术重建前交叉韧带40例（传统手术组）,术前进行股骨、胫骨隧道理想位置的设计。术中C臂透视机获得正侧位影像后传输入计算机系统形成虚拟工作界面。膝关节周围分别固定股骨、胫骨追踪器。手术工具装配追踪器。经过注册及校准后,导航系统通过捕获追踪器发射的信号实时跟踪手术工具的位置方向,并叠加在工作界面上,达到导航的目的。本文对导航手术组进行总结,术后进行胫骨隧道位置测量,并与传统手术组进行比较。结果术后测量,导航手术组胫骨隧道位置平均值45．90％（41．00％～49．80％,标准差2．36％）,传统手术组胫骨隧道位置在41．05％（范围25．00％～54．00％,标准差6．01％）,两组结果差异有统计学意义（P〈0．05）。同时导航组的平均手术时间较传统组延长20min,透视次数为4次。术后短期随访（1-3个月）,两组膝关节稳定性无明显差异。结论 X线影像导航系统辅助关节镜下前交叉韧带重建手术是安全、可行的,通过术前规划,可以使股骨、胫骨隧道位置更精确。     

计算机导航关节镜下前十字韧带重建术

目的介绍计算机导航技术辅助关节镜下前十字韧带重建术的术前规划和手术方法,比较导航技术辅助与单纯关节镜技术中股骨、胫骨隧道位置的优良率。方法根据术前标准正侧位X线片设计股骨、胫骨隧道的理想位置。术中“C”型臂X线机获得正侧位影像后输入计算机,形成虚拟工作界面。膝关节周围分别于股骨、胫骨侧安置“患者追踪器”。前十字韧带胫骨及股骨导向器上分别装配“工具追踪器”。经过注册及校准后,导航系统识别并捕获上述追踪器发射的信号,确定膝关节的位置,实时跟踪手术工具的位置和方向,并将隧道的虚拟路径叠加在工作界面上,供术者实时调整导向器的位置与方向,直至达到术前规划的要求。临床上完成计算机导航关节镜下前十字韧带重建术46例。对其中40例进行术后X线片测量,确定胫骨及股骨隧道的位置,并与同期进行的40例单纯关节镜下重建术隧道位置的测量结果进行比较。结果导航组胫骨隧道位置平均为45.35%±3.827%(37%￣53%),股骨隧道位置平均为62.25%±5.610%(52%￣73%);关节镜组胫骨隧道位置平均为41.05%±6.008%(25%～54%),股骨隧道位置平均为56.62%±7.316%(46%￣77%)。导航组的股骨及胫骨隧道位置较关节镜组偏后,差异有统计学意义(P<0.05),导航组的标准差小于关节镜组。结论计算机导航技术可以使关节镜下前十字韧带重建手术中胫骨及股骨隧道的位置更偏后,提高了手术准确性及可重复性。     

前交叉韧带重建中两种建立股骨隧道方法的比较

[目的]对关节镜下重建前交叉韧带(ACL)手术中,经胫骨隧道与髌下前内侧入路建立股骨隧道的长度、角度进行比较.[方法]在140例ACL移植重建患者中,70例采用经胫骨隧道、70例经前内入路建立股骨隧道,术中记录股骨隧道长度,术后行膝关节前后位及侧位X线检查,测量股骨隧道在冠状面与内外髁连线及矢状面与股骨干轴线夹角,并使用t检验进行统计分析.[结果]经胫骨隧道组及经前内人路组股骨隧道长度分别为(50.67±5.00) mm、(37.97±4.45) mm,后者股骨隧道长度短于前者,差异非常显著(P＜0.01)；冠状面股骨隧道角度两者分别为68.20°±6.92°；矢状面为45.45°±7.47°、32.81°±9.45°,无论在冠状面及矢状面,前内入路组股骨隧道角度均小于胫骨隧道组,差异非常显著(P＜0.01).[结论]在关节镜下ACL移植重建手术中,采用前内入路制备的股骨隧道,长度短、角度小.它可以减小“雨刮效应”和“蹦极效应”发生的可能,最终获得更好的临床效果.     

前内侧入路解剖重建单束前交叉韧带的临床评估

目的评估关节镜下经前内侧入路解剖重建单束前交叉韧带(ACL)的位置、形态及临床效果。方法对25例ACL断裂患者在关节镜下经前内侧入路应用解剖重建技术行单束ACL重建术,移植物应用自体腘绳肌腱。术后行X线、MRI检查,了解骨道情况,观察移植物形态及张力,并与11例健侧膝关节的正常ACL进行对比。应用Lysholm评分系统评估膝关节功能。结果术后X线片显示股骨隧道内口位于髁间窝顶与股骨后缘皮质线交叉点前缘,胫骨隧道内口位于髁间窝顶后方。MRI显示所有重建ACL张力良好,ACL上倾角为50.82°±4.57°,胫骨平台止点至前缘距离与平台纵径比值为0.50±0.04,两项与对照组比较差异均无统计学意义(P0.05)。患者均获得随访,时间为13~44个月。Lysholm评分术后为92.20分±4.29分,明显高于术前的64.76分±7.16分(P0.01)。结论关节镜下经前内侧入路解剖重建ACL的位置及形态接近解剖结构,早中期临床效果满意。     

经胫骨隧道与前内侧入路建立前交叉韧带股骨隧道的比较研究

目的 比较关节镜下前交叉韧带(ACL)重建术中经胫骨隧道与髌下前内侧入路建立股骨隧道的长度和角度。 方法回顾性分析2000年11月至2009年11月收治的102例ACL重建手术患者资料,其中50例采用经胫骨隧道建立股骨隧道（经胫骨隧道组）：男39例,女11例;年龄15～49岁,平均（27.9±7.6）岁。52例采用经前内侧入路建立股骨隧道（前内侧入路组）：男33例,女19例;年龄15～56岁,平均(30.5±10.7)岁。术中记录股骨隧道长度,术后行膝关节前后位及侧位X线片检查,测量股骨隧道在冠状面与内、外髁连线及矢状面与股骨干轴线的夹角,并进行统计学分析。 结果 经胫骨隧道组股骨隧道的平均长度[（50.9±5.0）mm]长于前内侧入路组[(37.8±4. 7)mm],差异有统计学意义(t=15.083,P=0. 000);经胫骨隧道组冠状面股骨隧道角度(68.6°±7.0°)、矢状面股骨隧道角度(45.1°±8.1°)均大于前内侧入路组(49.8°±7.7°)、33.7°±9.7°),差异均有统计学意义(t=12. 874,P=0. 000;t =5. 877,P=0. 000)。 结论关节镜下ACL重建术中,采用前内侧入路制备的股骨隧道长度短、角度小。     

关节镜下双股半腱及股薄肌腱经双胫骨隧道解剖重建膝前交叉韧带

目的：介绍在关节镜下应用自体双股半腱和股薄肌腱(DLSTG)经双胫骨隧道解剖重建膝前交叉韧带(ACL)的手术方法及术后随访结果。方法：在关节镜下对15例ACL断裂的患者行双胫骨隧道解剖重建：移植体股、胫骨端均采用近ACL解剖止点之Press-fit技术固定：结果：全部患者于术后6～8周恢复了正常的关节活动和行走步态：手术12～16周后恢复了低风险体育运动：术后1年，2名患者的Lachman试验Ⅰ度阳性；15名患者的IKDC评分为正常或接近正常；Tegner评分显示12名患者已恢复伤前运动水平；X线片示全部患者股骨、胫骨隧道无扩大：结论：关节镜下利用自体DLSTG及Press—fit固定技术施行双胫骨隧道的ACL解剖重建在技术上可行，并有利于伤膝功能的快速恢复。     

电磁导航系统辅助后交叉韧带重建胫骨隧道定位的效果评价

目的评价电磁导航系统辅助后交叉韧带重建胫骨隧道定位的效果,为临床提供更优手术方式。方法选取新鲜冰冻成人下肢膝关节标本30例,不计性别、年龄及左右侧,将标本CT数据导入电磁导航系统行三维建模,术前完成最优手术路径规划,术中于电磁导航系统实时监测下完成胫骨隧道重建,并测量胫骨隧道矢状角度、隧道长度与出口位置。结果 30例膝关节中,28例钢针出针点位于术前规划好的足印区内,为有效的胫骨隧道,电磁导航辅助下胫骨隧道定位的有效率为93.33%,有效例数中优良率为85.71%(24/28)。术前规划矢状角度为(59.72±2.32)°,术后实测为(59.55±2.35)°,误差为(0.16±1.9)°;术前规划胫骨隧道长度为(69.56±2.79)mm,术后实测为(70.34±2.38)mm,误差为(-0.78±2.27)mm。术前规划胫骨虚拟隧道矢状角度、长度与术后实测比较差异均无统计学意义(P0.05)。结论电磁导航系统辅助下行后交叉韧带重建中胫骨隧道定位,精准度高,操作方便,可以作为一种良好的辅助定位方式。     

经前交叉韧带腋下胫骨定位的后交叉韧带重建术

[目的]介绍关节镜下经前交叉韧带(anterior cruciate ligament, ACL)腋下胫骨定位的后交叉韧带(posterior cruciate ligament, PCL)重建术的技术及初步疗效。[方法] 2016年3月～2018年11月,对20例后交叉韧带断裂患者采用关节镜下经ACL腋下定位胫骨骨道,保残重建后交叉韧带。术中保留PCL残束,经前入路由内向外建立PCL股骨隧道,经ACL腋下置入胫骨隧道定位器,在后内入口观察下,于PCL止点平台下建立胫骨隧道。将移植腱由胫骨前侧经胫骨隧道拉入、再引入股骨隧道,股骨侧悬吊固定,拉紧移植物,胫骨侧挤压螺钉和"n"形钉固定。[结果]所有患者均顺利手术,无严重并发症。随访1年以上,Lysholm评分从术前(38.75±14.52)分显著增加至术后1年(93.70±4.23)分(P0.05)。影像测量后向应力胫骨后移由术前(10.81±3.07) mm减少至术后1年(3.86±1.10) mm (P0.05)。[结论]经ACL腋下定位胫骨骨道重建PCL,能精确的偏下偏外定位胫骨骨道;并可以最大程度的保留PCL残端,有利于重建术后韧带的愈合。     

前十字韧带双束重建术后CT测量骨隧道大小的价值

目的 探讨前十字韧带(ACL)双束重建术后CT测量骨隧道大小的价值.方法 47例单纯ACL断裂自体胭绳肌腱双束重建患者,男42例,女5例;年龄18～52岁,平均26.8岁.采用双束四隧道八股肌腱重建ACL方法 ,隧道外悬吊式固定.术后分别在X线及CT片上测量胫骨、股骨骨隧道的直径,并与术中钻孔值比较.结果 术中胫骨浅束钻孔直径平均(0.5979±0.0521)cm,胫骨深束钻孔直径平均(0.7479±0.0651)cm,股骨浅束钻孔直径平均(0.5734±0.0487)cm,股骨深束钻孔直径平均(0.6947±0.0732)cm.X线测量结果 示:胫骨浅束直径为0.545±0.762 cm,平均(0.6369±0.0638)em;胫骨深束直径为0.601±0.987 cm,平均(0.7784±0.0841)em;股骨浅束直径为0.534±0.644 cm,平均(0.5780±0.0305)cm;股骨深束直径为0.488～0.817 cm,平均(0.6723±0.0754)cm.CT 测量结果 示:胫骨浅束直径平均(0.6009±0.0502)cm,胫骨深柬直径平均(0.7497±0.0677)cm,股骨浅束直径平均(0.5662±0.0375)cm,股骨深束直径平均(0.7002±0.0709)cm.CT 测量值与术中钻孔值比较差异无统计学意义(P＞0.05).结论 CT 测量方法 可以真实反映胫骨、股骨骨隧道大小,适用于ACL重建术后骨隧道扩大的研究.     

前交叉韧带重建术止点定位的临床研究

[目的]通过比较不同临床结果下前交叉韧带重建术骨隧道止点位置的差异，探讨理想骨隧道的影像学位置。[方法]选择55例关节镜下前交叉韧带重建术病例，对过伸位X线侧位片测量并分别计算股骨、胫骨止点及Blumensaat线的胫骨平台投影点相对位置。根据临床结果不同分两组对上述资料分析影像表现差别。[结果]股骨侧止点位置在不同临床结果的两组间有显著性差异，胫骨止点位置和Blumensaat线投影点位置组间无差异性。胫骨止点均位于Blumensaat线投影点之后。[结论]股骨侧止点位置偏前临床效果较差，大致位于Blumensaat线距股骨外侧髁前缘交点的65％-69％之间。胫骨侧止点在伸直位Blumensaat线胫骨投影点之后，大致位于胫骨平台前后直径距前缘38％-41％之间。术前进行患膝关节的过伸位X线片检查，并测量Blumensaat线的胫骨投影位置，有助于为术前胫骨止点定位提供参考。     

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.