全膝关节置换术中股骨前髁厚度的影像学研究

目的通过全膝关节置换术前、术后影像学测量及患者膝关节功能评估,初步总结中老年膝骨关节炎(KOA)人群股骨前髁厚度(ACO)的影像学参数,并探讨在全膝关节置换术中ACO对术后膝关节活动度的影响。方法自2010年1月至2012年12月因KOA行全膝关节置换术患者69例(82膝),男16例(20膝),女53例(62膝);年龄45~78岁,平均63岁。测量患者术前及术后12周侧位X线片上股骨前髁的厚度、关节活动度及HSS评分,进行统计学分析。结果男性患者ACO平均值为(7.3±1.7)mm,女性为(7.3±1.4)mm,不同性别之间ACO差异无统计学意义(P>0.01);术前ACO为(7.3±1.5)mm,术后为(6.4±1.7)mm,差异有统计学意义(P<0.01);关节活动度及HSS评分术前与术后相比差异具有统计学意义(P<0.01)。结论中老年KOA人群ACO无性别差异;膝关节置换术后股骨前髁较术前变小,与股骨假体的设计及术中股骨截骨有关;膝关节股骨假体截骨时,可以适当前移截骨模块或增大股骨假体型号,在4 mm范围内不会引起髌股关节的填塞。     

Oxford单髁置换治疗膝内侧间室骨性关节炎

目的探讨Oxford单髁置换(UKA)治疗膝内侧间室骨关节炎的临床疗效。方法采用Oxford UKA治疗25例膝内侧间室骨关节炎患者(26膝)。采用膝关节功能HSS评分评价疗效。结果 25例患者均获随访,时间8~16个月。术后患膝关节疼痛均明显缓解,关节活动度改善,生活质量提高。术后2周、3个月、6个月膝关节功能HSS评分、膝关节活动度均较术前增加,差异均有统计学意义(P0.01),术后2周、3个月、6个月膝关节屈曲挛缩度数均较术前减少,差异均有统计学意义(P0.01)。结论 Oxford UKA治疗膝内侧间室骨关节炎,具有术后功能恢复良好、并发症少等优点。     

股骨后髁偏距与高屈曲后稳定型全膝置换术后膝关节屈曲度的相关性分析

目的 分析股骨后髁偏距与高屈曲后稳定型全膝关节置换术中、术后膝关节屈曲度的相关性,探讨其在股骨假体设计中的意义.方法 前瞻性分析2005年3月至2006年10月使用NexGen LPS-Flex假体行单侧全膝关节置换术的男性(男性组)、女性(女性组)各50例骨关节炎患者临床与影像学资料.对患者手术前、后股骨后髁偏距的改变值与术中及术后2年膝关节屈曲度改善值的相关性进行分析.结果 100例患者术后股骨后髁偏距较术前减小(3.4±3.3)mm,减小程度女性高于男性[女性:(-5.4±3.1)mm,男性:(-1.5±2.0)mm,P<0.05].后髁偏距的改变值与术后2年膝关节屈曲度改善值在患者整体内并无相关性(P>0.05).但若分别在男性与女性组内对其观察,则两者间均呈具有正向相关性(P<0.05);术中患者整体、男性组、女性组内膝关节屈曲度改善值均与后髁偏距的改善值呈正向相关性(P<0.05).结论 重建股骨后髁偏距与高屈曲后稳定型全膝置换术后膝关节屈曲度的获得间存在相关性;使用以西方人解剖参数设计的假体不能充分匹配国人特别是我国女性股骨远端的几何学形态,兼以前参照技术进行前后髁截骨通常会导致其后髁偏距的减少,降低了其获得更大膝关节屈曲度的可能,假体设计有必要考虑不同种族和性别间的解剖差异.     

股骨髁前后径与内外径比值对膝关节置换的影响

[目的]测量股骨髁的前后径、内外径,分析两者的比值对全膝关节置换的影响。[方法]选取2015年10月～2017年12月行全膝关节置换的170例患者,手术前利用X线片在膝关节上对股骨髁的前后径、内外径进行测量,算出两者比值,对比假体数据,将比值>0.9的60例患者分为两组,对照组:采取髓内长定位杆截骨;研究组:采取髓内短定位杆截骨,均为30例,对两组临床效果进行比较。[结果]两组患者术后均未出现感染、假体周围骨折及假体松动;两组患者术后KSS评分、伸直角度和伸膝障碍所占比例差异均无统计学意义(P>0.05);两组膝关节屈曲角度、股骨假体屈曲角度和股骨前端切迹差异均有统计学意义(P<0.05)。[结论]针对股骨髁前后径、内外径比值较大者,采取髓内短定位杆截骨能够维持伸屈稳定,降低截骨切迹和假体周边骨折发生概率,临床应用效果良好。     

固定平台后稳定型假体与旋转高屈曲型假体治疗膝骨性关节炎的早期疗效比较

目的评价人工全膝关节置换(total knee replacement,TKR)中使用固定平台后稳定型假体与旋转高屈曲型假体治疗骨性关节炎的早期临床疗效。方法对我院2007年1月—2009年12月收治的68例骨关节炎患者施行TKR手术,其中应用固定平台后稳定型假体32例38膝,旋转高屈曲型假体36例44膝,通过测量手术前及末次随访时的膝关节活动度和美国特种外科医院膝关节评分(hospital for special knee surgery score,HSS)对两种假体置换方式的临床疗效进行比较。结果 68例患者获随访3～26个月,平均19个月。根据HSS评分标准,末次随访时优47例(69.1%),良17例(25.0%),可4例(5.9%),总优良率94.1%。两组之间术前活动度以及术前、末次随访时HSS的差异无统计学意义(P0.05),而旋转高屈曲型假体组在末次随访活动度方面较固定平台后稳定型假体组为高(P0.05)。结论高屈曲度人工膝关节假体在运动学上有潜在的优势,有助于改善关节功能,减轻接触应力和假体磨损;固定平台后稳定型假体手术方式简单、疗效肯定、术后并发症少,对不需要从事高屈曲活动、经济较为困难以及高龄患者是一种可供选择的假体。     

两种股骨截骨角度对膝关节置换术中股骨假体冠状位对线的影响

[目的]研究两种股骨远端外翻截骨角测定方法在膝关节置换术中对股骨假体对线的影响。[方法]对本院2015年3月~2015年6月由两名主刀医师完成的连续111例共137膝全膝关节置换术进行回顾性研究。两名主刀医师术前计划时在下肢全长X线片上测量股骨远端外翻截骨角度的方法不同,并以此分为两组。第一组利用股骨远端1/3解剖轴与股骨力线轴夹角(DFMA)作为股骨远端外翻截骨角,共71膝;第二组利用股骨解剖轴与股骨力线轴夹角(FMA)进行外翻截骨,共66膝。术后测量标准下肢全长X线片中股骨力线轴与股骨假体远端内外侧髁连线之夹角并比较两组结果的差异。[结果]两组患者的年龄、BMI、术前内翻角度、术前HSS评分、术后HSS评分差异均无统计学意义(P=0.149~0.985)。DFMA组术中所使用的股骨外翻截骨角度实际为6.08°±1.57°,FMA组为4.82°±0.74°,两组截骨角度差异有统计学意义(P<0.05)。DFMA组76.1%的术后股骨假体在0°±2°范围内,显著优于FMA组的51.50%,(P=0.005),并且DFMA组74.60%的术后下肢力线在0°±3°范围内,显著优于FMA组的53.00%,(P=0.008)。DFMA组术后下肢力线角度与FMA组差异无统计学意义(1.60°±2.46°vs 1.98°±3.35°,P=0.458)。[结论]内翻膝使用股骨远端1/3解剖轴与力线轴夹角作为个性化股骨外翻截骨角度,术后股骨假体冠状面位置优于使用股骨解剖轴与力线轴夹角。应用股骨解剖轴线确定股骨外翻截骨角度往往偏小,导致残留膝关节内翻畸形。     

CT扫描在全膝关节置换术中髌股关节轨迹不良股骨旋转力线的研究

[目的]探讨CT扫描技术检测全膝关节置换术(TKA)中对髌股关节轨迹不良股骨旋转截骨角度确定的作用。[方法]将72例(74膝)TKA中髌股关节轨迹不良患者随机分为两组:(1)CT扫描组35例(36膝):术前CT扫描确定股骨后髁角,术中采用CT确定的股骨后髁角进行股骨外旋截骨,其余TKA手术操作相同;(2)对照组37例(38膝):术中采用与后髁轴线呈固定外旋3°进行股骨外旋截骨,两组术后均行CT扫描分析股骨假体旋转不良角度并对其绝对值进行比较。[结果]术后随访时间24¹20个月,平均53.6个月。CT扫描组KSS功能评分从术前的平均35分提高到术后平均81分;对照组KSS功能评分从术前的平均34分提高到术后平均83分,两组比较均无显著性差异(P>0.05)。CT扫描组:TKA术后股骨假体旋转不良角度为1.4°±0.06°,对照组为2.5°±0.14°,两组比较差异有统计学意义(t=4.18,P<0.01)。CT扫描组股骨假体旋转不良率为12.5%,经验组为24.6%,两组比较差异有统计学意义(x2=16.58,P<0.01)。[结论]术前CT扫描确定股骨假体旋转参考轴,可用于指导全膝关节置换术中股骨旋转截骨角度,有效提高TKA手术股骨假体旋转力线的准确性。     

旋转铰链型膝关节置换术后中期临床随访报告

[目的]探讨旋转铰链型人工膝关节临床应用的适应证,评价中期的临床疗效,分析术后并发症的原因。[方法]回顾性研究1999～2007年间应用旋转铰链型膝关节假体进行的初次膝关节置换病例,共计34例42膝,平均随访时间6.4年(2.3～10.4年)。这些患者膝关节术前均合并有较为严重的膝内翻、膝外翻或屈曲挛缩畸形,存在不同程度的膝关节不稳定或骨缺损。术后采用HSS评分及膝关节活动度评价临床效果。[结果] 1例术后发生人工关节周围迟发性感染;1例因外伤导致股骨假体近端的股骨干骨折;行切开复位内固定后发生假体周围感染;3例术后复查X线提示有髌骨倾斜或半脱位。所有患者膝关节疼痛均得到明显缓解,行走及上下楼能力均得到明显改善。HSS评分从术前的40.5分增加到术后的89.0分。[结论]旋转铰链型膝关节除适用于人工关节翻修术,还可应用于合并有重度膝关节畸形,存在大量骨缺损或膝关节不稳定的关节炎患者的初次置换。严格选择适应证,准确的手术操作,应用该假体可以获得满意的中期临床疗效。但如果术后出现合并症,处理将比较困难。     

股骨侧假体与胫骨平台角度对膝关节活动度的影响

目的探讨股骨假体屈曲角、胫骨平台后倾角对人工全膝关节置换术后关节活动度的影响。 方法选择2014年1月至2016年12月在广西壮族自治区龙潭医院接受人工全膝关节置换的387例患者病历资料进行回顾性分析,记录患者性别、年龄、身体质量指数、置换关节数、手术时间、术前关节活动度、术前最大屈膝度、术前美国特种医院(HSS)评分、术前疼痛评分、伴随疾病、个人史、康复介入时间、术后1 d疼痛评分、胫骨平台后倾角、股骨假体屈曲角。计量资料组内比较采用配对样本t检验,组间比较采用独立样本t检验,以术后1年患者关节活动度为因变量,其他参数为自变量行秩相关分析和多元回归分析,观察上述指标与术后1年膝关节活动度≥90°的相关性。 结果术前HSS评分为(47±10)分,术后1年HSS评分为(87±6)分,差异有统计学意义(t＝15.820,P<0.01);术前关节活动度为(86±7)°,术后关节活动度为(106±9)°,差异有统计学意义(t＝6.058,P<0.01)。性别、术前关节活动度、术前最大屈膝度、术前HSS评分、胫骨平台后倾截骨角度与膝关节活动度呈正相关(P<0.05);年龄、身体质量指数、置换关节数、术中出血量、术前疼痛评分、高血压、糖尿病、康复介入时间、术后1 d疼痛评分、股骨假体屈曲度与关节活动度呈负相关(P<0.05);手术时间、吸烟、饮酒与术后膝关节活动度无显著相关性(P>0.05)。多元线性逐步回归分析结果显示,胫骨平台后倾截骨角度、股骨假体屈曲角、术前疼痛评分、术前关节活动度是影响膝关节置换术后1年关节活动度的独立因素(P <0.05)。 结论股骨假体屈曲角与全膝关节置换术后关节活动度呈负相关,胫骨平台后倾截骨角度与全膝关节置换术后关节活动度呈正相关。     

64例应用国产膝关节假体行全膝关节置换术的近期疗效观察

目的评价应用国产膝关节假体行人工全膝关节置换术的效果。方法自2003年5月至2011年5月，使用国产CL～高屈曲后稳定型假体治疗64膝，对照组12膝使用进口膝关节假体进行置换，对比组问及组中术前、术后12W、26W的HSS评分，并比较术后假体力线、髌骨轨迹不良的发生率。结果国产及进口假体组术前、术后12W、26W的HSS评分比较均有统计学差异，术后HSS评分均优于术前。两组间HSS评分、术后假体力线、髌骨轨迹不良发生率无统计学差异。结论国产膝关节假体可以取得良好的临床疗效，适合大力推广。     

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.