纤维环缝合对腰椎稳定性及椎间盘内压力影响的研究

[目的]通过生物力学测试研究纤维环缝合对腰椎稳定性以及椎间盘压力的影响。[方法]选取10具L4/5的小牛脊柱标本在纤维环完整、切开以及缝合3种状态下进行生物力学测试,观察标本在屈伸、侧弯、旋转时的活动度(ROM)、中性区(NZ)的变化以及椎间盘内压力的变化。[结果]纤维环切开后,在前屈、左右侧弯的ROM和NZ值较完整组显著增加(P<0.05),纤维环缝合后,上述方向上的ROM和NZ值较切开组显著下降(P<0.05),而与完整组无明显差异;3组在后伸、左右旋转的ROM和NZ值均无明显差异。完整组、切开组和缝合组的泄露压力分别为(5.0±0.0)MPa、(0.5±0.5)MPa和(1.7±0.8)MPa,纤维环缝合组的泄露压力较切开组增加,但仍小于完整组。[结论]腰椎纤维环切开术后缝合纤维环能部分恢复椎间盘内压力和腰椎节段运动的稳定性。     

复方利多卡因乳膏在包皮环切术中止痛效果的研究

目的：探讨在使用一次性包皮环切缝合器进行包皮环切术时使用复方利多卡因乳膏涂抹时间长短对麻醉效果的影响。方法：收集我院门诊 2013 年 5 月—2018 年 5 月行包皮环切手术患者 150 例,年龄分布在 15~42 岁之间,随机分成三组,每组 50 例,术前准备完善后使用复方利多卡因乳膏涂抹包皮并计时,分 A 组 10 min、B 组 20 min、C 组 30 min 均使用一次性包皮环切缝合器行包皮环切术,术后对术中疼痛评分、术后出现疼痛时间、术后并发症及患者满意度进行统计分析。结果：三组患者术中疼痛评分A组：（4.16±0.79）,B组：（1.91±0.70）,C组：（1.18±0.53）,各组比较有显著性差异（P<0.05）;术后出现疼痛时间分别为：A 组：（50.16±1.22） min,B 组：（60.00±1.11） min,C 组：（59.90±1.15） min,AB 及 AC 比较有显著性差异（P<0.05）,BC 比较无统计学差异（P>0.05）;术中追加麻药的比率三组分别为：38%、12%、6%,AB 及AC 比较有显著性差异（P<0.05）,BC 比较无统计学差异（P>0.05）;满意率分别为 A 组：60%,B 组：90%,C 组：96%,三组比较均有显著性差异（P<0.05）;并发症比较在血肿及包皮术后瘀斑方面三组均有显著性差异（P<0.05）。结论：在使用一次性包皮环切缝合器做包皮环切术时使用复方利多卡因乳膏做表面麻醉是安全有效的,且随涂抹时间延长其麻醉效果好。     

人工生物膜修复椎间盘纤维环的研究

目的 用不同方法处理椎间盘纤维环,观察人工生物膜对椎间盘纤维环缺损的修复作用.方法 成年山羊8只,雌雄各4只,对每只羊的腰椎(腰2/3、腰3/4、腰4/5)椎间盘纤维环进行随机处理,处理方法包括:(1)暴露出椎间盘纤维环,不作任何处理;(2)暴露出椎间盘纤维环后,将其切开,用人下生物膜填充缺口;(3)暴露出椎间盘纤维环,尖刀将其切开,作为对照组.12周后,通过生物力学测试、核磁共振(MRI)及脱钙病理切片染色观察椎间盘纤维环的修复效果.结果 12周后,测试纤维环承受最大压力,单纯暴露组为(4.92±0.17)MPa,纤维环单纯切开组为(2.48±0.39)MPa,人工生物膜修复组为(3.76±1.56)MPa.人工生物膜修复组与单纯切开组,椎间盘纤维环完整性及生物强度均不如单纯暴露组,人工生物膜修复组优于单纯切开组,两组间的差异有统计学意义(P＜0.05),人工生物膜可与椎间盘纤维环的胶原纤维良好融合.结论 人工生物膜可对椎间盘纤维环缺口起到修复作用,能使其生物力学强度平均恢复76.4%,人工生物膜可以促进椎间盘结构完整性的恢复.     

塑型卵圆钳经皮缝合与切开缝合治疗新鲜闭合性跟腱断裂的对照研究

目的 比较塑型卵圆钳经皮微创缝合技术和切开缝合技术治疗新鲜闭合性跟腱断裂的临床疗效。方法 回顾性研究自2014年1月至2016年10月收治的73例新鲜闭合性跟腱断裂病人,最终入组共70例,根据手术方式的不同分为两组：微创组（36例）借助自制的塑型卵圆钳,通过小切口经皮缝合修复跟腱;常规组（34例）采用常规跟腱内侧纵行切口,连续锁边缝合修复跟腱。记录两组手术时间、术中出血量、术后并发症、恢复至伤前运动水平的时间、末次随访时的美国足踝外科医师协会（American Orthopedic Foot and Ankle Society, AOFAS）踝与后足功能评分,术后1年复查MRI评估跟腱修复状况。结果 两组病人获得16~44个月（平均30个月）随访,其中微创组手术时间为（45.34±6.73） min,术中出血量为（15.12±4.11） ml;常规组手术时间为（69.33±13.44） min,术中出血量为（25.47±7.19） ml,两组比较,差异均有统计学意义（P均＜0.05）。微创组2例病人切口延迟愈合,2例出现线结刺激症状,1例腓肠神经损伤,1例于术后半年外伤后再断裂;常规组3例伤口浅表感染,2例出现深部感染,无腓肠神经损伤及跟腱再断裂。末次随访AOFAS评分：微创组为（95.81±2.35）分,常规组为（93.61±4.83）分;微创组有29例病人（21.0±4.7）周（20~24周）恢复至伤前运动水平,常规组有26例（23.0±3.5）周（21~31周）恢复至伤前运动水平;上述指标比较,差异均无统计学意义（P均＞0.05）。术后1年MRI均显示跟腱连续性完整,未观察到跟腱囊性变。结论 自制塑型卵圆钳经皮缝合技术修复新鲜闭合性跟腱断裂手术时间短,术后恢复更快,且并不增加跟腱再断裂发生率。     

椎间孔镜下髓核摘除后纤维环缝合修复治疗腰椎间盘突出症的临床观察

【摘要】 目的：探讨在椎间孔镜下行髓核摘除+纤维环缝合修复在单节段腰椎间盘突出症患者中的临床应用及效果。方法：回顾性分析我院2018年1月～2019年12月行椎间孔镜手术治疗的60例单节段腰椎间盘突出症患者的临床资料，男45例，女15例；年龄18～56岁（平均45±5岁）。其中30例行椎间孔镜下常规髓核摘除（A组）；30例行髓核摘除后，镜下行纤维环缝合修复（B组）。采用腰腿痛视觉模拟评分（visual analog scale，VAS）、Oswestry功能障碍指数（Oswestry disability index，ODI）和影像学检查对术后疗效进行分析评价。结果：所有患者均获随访，随访时间12～24个月，平均15个月。两组患者术后症状均明显缓解，术后各时间点腰腿痛VAS评分（术后、术后3个月、术后1年及末次随访）显著低于术前（P<0．05），组间比较无显著性差异（P>0．05）；术后各时间点ODI均低于术前（P<0．05），组间比较无显著性差异（P>0．05）。术后3个月复发2例（均为A组患者），1例予再次椎间孔镜手术，1例予椎间盘切除、椎间植骨融合术；其余患者影像学复查无复发，无手术节段失稳。结论：椎间孔镜下纤维环缝合符合微创理念，能即刻闭合纤维环破口，可能促进纤维环修复，降低术后复发率，近期临床效果满意。     

人体组织粘合剂在包皮环切中的应用价值（附258例报告）

目的对比研究人体组织粘合剂与传统缝合方法对包皮环切术切口的治疗效果。方珐门诊包皮环切术488例随机分成A、B两组,A组258例切口应用人体组织粘合剂粘合,B组230例应用丝线或可吸收线间断缝合,观察并比较关闭切口时间、切口疼痛发生率、术后疼痛持续时问、术后水肿情况、切口愈合分级的情况。培杲在关闭切口时间、切口疼痛发生率、术后疼痛持续时间方面A组与B组有显著差异性（P〈0．05）。在术后水肿情况、切口愈合分级方面A组与B组无显著性差异（P〉0．05）。站论应用人体组织粘合剂行包皮环切术具有诸多优点,在包皮环切手术中值得广泛推广。     

生物可分解吻合环与手工缝合在肠吻合术中的随机对照研究

目的： 评估生物可分解吻合环在肠道吻合手术中的应用。方法：将需行肠吻合术的患者随机分成两组：吻合环组92例，手工缝合组94例，共186例。术后分别记录与吻合口有关的并发症、肠功能恢复时间等情况。127例结肠肿瘤患者（吻合环组62例，手工缝合组65例）术后随访时观察吻合口炎症发生的情况。两组病例一般资料分布均衡。结果：2例(2.17%)患者术中出现使用吻合环困难。两组各死亡1例，但均与手术操作无关。术后肠功能恢复时间：吻合环组（61.4±8.6）h，手工缝合组（68.3±9.7）h，两组之间差异无显著性（P>0.05）。吻合环组发生术后吻合瘘1例（1.1%），手工缝合组发生2例（2.1%）（P>0.05）；吻合环组发生术后吻合口出血2例（2.2%）,手工组缝合组发生1例（1.1%）（P>0.05）；两组术后均未发生吻合口梗阻；吻合环组发生吻合口炎症2例（3.2%），手工缝合组发生13例（20.0%），两组之间差异有显著性（P<0.01）。结论： 生物可分解吻合环是一种安全有效的肠吻合装置。     

复合血管内皮祖细胞的组织工程骨修复兔桡骨缺损的实验研究

目的评价复合血管内皮祖细胞（EPCs）的组织工程骨修复兔桡骨大段缺损的效果。方法选用68只新西兰大耳白兔，随机分为三组。制成桡骨中段15mm骨缺损模型，各组植入不同材料，实验组（EPCs组）：植入EPCs＋经成骨诱导的骨髓基质干细胞（BMSCs）＋脱钙骨基质（DBM）；对照组：植入BMSCs＋DBM；阴性对照组：单纯植入DBM。术后3d，2、4、8、12、16周行X线片、组织学光镜、透射电镜观察及12、16周生物力学测试。结果实验组的成骨活跃程度、骨愈合速度均明显优于对照组。12周实验组抗扭强度[（5．57±0．13）MPa]与正常对照组无差异[（5．44±0．26）MPa]，明显强于对照组[（4．72±0．58）MPa]，差异有统计学意义（P〈0．05）；16周实验组抗扭强度[（8．57±2．10）MPa]明显强于对照组[（5．43±0．22）MPa）1和正常对照组[（5．44±0．26）MPa）]，差异均有统计学意义（P〈0．05）；实验组与对照组各项指标明显优于阴性对照组，差异均有统计学意义（P〈0．05）。结论复合EPCs的组织工程骨骨诱导能力强，能促进骨愈合，是修复大段骨缺损的有效方法。     

三种纤维环处理方式对腰椎生物力学影响的三维有限元分析

目的:通过建立"一"字型切口、环形切口、纤维环缝合的有限元分析模型,利用有限元分析方法,评估三种纤维环处理方式对于腰椎生物力学的影响。方法:选取健康成人L4/5腰椎节段的CT的DICOM结果,通过逆向建模方式建立人体正常腰椎模型、环形切口模型、"一"字型切口模型及缝合模型,测量腰椎在正常轴向压力的情况下,前屈、后伸、侧弯、旋转四种工况下的生物力学数据。结果:通过有限元分析方法计算正常椎体及三种不同纤维环处理方式的模型的应力数据,结果显示纤维环切开后,各种工况下纤维环、髓核的最大应力值均较正常模型增加;纤维环缝合后,在前屈后伸旋转工况下的最大应力,均低于"一"字型切口和环形切口;与未缝合模型相比,纤维环缝合模型的各部分在各种工况下的应力分布都更加均匀。结论:纤维环缝合后椎间盘、髓核和纤维环应力分布较未缝合模型均匀,缓解纤维环切开后造成的纤维环应力集中问题,对维持椎间盘的稳定性及防止术后再突出能起到积极作用。     

“立体缝合”技术在腹腔镜巨大切口疝修补术中的应用疗效

背景与目的 巨大切口疝的治疗是疝和腹壁外科领域的难点,尤其是如何缝合关闭筋膜缺损的问题。目前临床上常用的缝合方法应用于修补巨大切口疝中常面临诸多问题,如张力过大、无法消灭死腔等。基于缝合材料的发展,笔者团队前期开创了一种新的缝合技术—“立体缝合”,将其应用于切口疝修补中,可以很好地解决前述问题。本研究通过对比腹腔镜巨大切口疝修补术中应用“立体缝合”技术和常规缝合技术的两组患者的临床疗效,探讨“立体缝合”技术在巨大切口疝修补术中的临床价值。方法 回顾性分析2018年1月—2020年6月中山大学附属第六医院胃肠、疝和腹壁外科行腹腔镜腹腔内补片修补术的巨大切口疝患者资料,其中43例采用“立体缝合”处理疝囊和缺损（研究组）,36例采用传统缝合方法关闭缺损（对照组）,比较两组患者的相关临床指标。结果 研究组无中转开放病例,均实现了筋膜缺损的完全关闭,对照组中转开腹7例（19.44%）,无法完全关闭缺损5例（13.89%）;两组中转开放率与无法完全关闭缺损发生率差异有统计学意义（P=0.003,P=0.017）。研究组平均关闭筋膜缺损缝合时间（89.84±15.29）min,平均手术时间（181.51±18.23）min,平均术中出血量（26.84±12.67）mL,对照组平均关闭筋膜缺损缝合时间为（61.28±14.09）min,平均手术时间（157.72±19.17）min,平均术中出血量（27.25±11.83）mL,两组关闭筋膜缺损缝合时间及手术时间差异有统计学意义（均P<0.001）,出血量差异无统计学意义（P=0.871）。研究组术后手术部位事件（SSO）发生率明显低于对照组（2.33% vs. 16.77%,P=0.043）,两组术后复发率差异无统计学意义（0 vs. 2.8%,P=0.456）。研究组术后下床时间（22.36±4.45）h,术后住院时间（5.23±1.26）d,住院费用为（75 924.21±6 065.61）元,对照组术后下床时间（22.92±5.15）h,术后住院时间（5.46±1.93）d,对照组为（74 185.99±5 476.48）元,两组该3项指标差异均无统计学意义（P=0.192,P=0.440,P=0.283）。结论 “立体缝合”技术应用于巨大切口疝修补术中,可减少中转开腹发生率,有效关闭筋膜缺损,减少术后发生手术部位事件的风险。     

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.