自体血回输对病人血浆肝素含量的影响

目的　观察自体血回输对病人血浆中肝素含量的影响 ,探讨肝素在血液回收时的应用。方法　自体血液回输组 (n =32 )与异体输血组 (n =30 )骨科、脑科择期手术病人 ,男女各半 ,年龄 18～ 48岁 ,术前肝、肾、凝血功能均正常 ,无其他血液系统疾病。自体回输血量及异体输血量均超过 10 0 0ml。采用凝固法测定血浆中肝素含量 ;ACT Ⅱ型测定仪测定血中活化凝血时间 (ACT)。结果肝素含量 :自体血液回输组 ,术前、输血前、输血后 2小时肝素含量分别为 (0 6 5± 0 2 7)、(0 6 8±0 2 0 )和 (0 72± 0 19)U/ml;异体输血组分别为 (0 6 3± 0 2 4)、(0 6 7± 0 2 8)和 (0 6 9± 0 2 0 )U/ml。两组间均无显著差异 (P >0 0 5 )。ACT :自体血回输组三个不同时间分别为 (86 10± 2 0 5 4)、(133 5 0± 2 9 6 5 )和 (95 0 5± 2 9 71)秒 ;异体输血组分别为 (88 42± 18 37)、(131 70± 2 7 36 )和(92 86± 14 35 )秒。两组ACT值输血前均明显长于术前 (P <0 0 5 ) ,术前与输血后 2小时无显著差异 (P >0 0 5 )。结论　自体血液回输组与异体输血组术前、输血前、输血后 2小时肝素含量无显著差异。自体血回输中使用肝素抗凝适量 ,安全可行     

α1受体阻滞剂联合抗生素治疗慢性前列腺炎疗效及机制

目的 :观察α1受体阻滞剂联合抗生素治疗慢性前列腺炎 (CP)的疗效 ,初步探讨α1受体阻滞剂缓解CP症状的机制。　方法 :将 80例CP患者随机分成 2组 ,每组 4 0例 :治疗组口服特拉唑嗪 2mg及左旋氧氟沙星 0 .2g ,每日 2次 ;对照组仅口服左旋氧氟沙星 0 .2g ,每日 2次。治疗 6周 ,观察治疗前后慢性前列腺炎症状指数评分 (NIH CPSI)、前列腺按摩液常规及尿流动力学指标的变化。　结果 :治疗组NIH CPSI由治疗前 (31.8± 7.4 )分降至 (15 .5± 6 .6 )分 ,对照组NIH CPSI由治疗前 (30 .9± 7.1)分降至 (2 1.4± 6 .2 )分 ,治疗组改善程度较对照组更为显著 (P <0 .0 5 )。治疗组治疗前后最大尿流率 (MFR)分别为 (16 .5± 6 .3)ml/s和 (2 0 .4± 4 .6 )ml/s,两者差异有显著性 (P <0 .0 5 ) ;治疗组治疗前后最大尿道压 (MUP)分别为 (92 .5± 15 .3)cmH2 O和 (72 .5± 13.4 )cmH2 O ,两者差异有显著性 (P <0 .0 5 ) ;对照组治疗前后MFR分别为 (16 .1± 5 .8)ml/s和 (17.3± 6 .8)ml/s,MUP分别为 (93.2± 14 .8)cmH2 O和 (91.7± 13.6 )cmH2 O ,治疗前后差异均无显著性 (P >0 .0 5 )。　结论 :α1受体阻滞剂可降低尿道压力 ,缓解前列腺内尿液返流 ,与抗生素合用可提高疗效。     

二种胰肠吻合术吻合口创伤愈合的实验研究

目的　观察比较两种胰肠吻合方法创伤愈合过程。　方法　按吻合方法不同将动物分为捆绑式胰肠吻合组 (Ⅰ组 )和套入式胰肠端端吻合组 (Ⅱ组 ) ,分别在术中、术后 5、10d活体测定吻合口破裂压和离断力 ,并做病理观察。　结果　 (1)破裂压 :Ⅰ组 ,0、5、10d分别为 (139 7± 8 0 )mmHg、(178 7± 9 7)mmHg和 (2 6 8 8± 12 8)mmHg ,Ⅱ组则为 (6 7 3± 7 9)mmHg、(96 2± 10 4 )mmHg和 (130 6± 9 3)mmHg。Ⅰ组和Ⅱ组在 0至 5d和 5至 10d两时间段分别增加 2 7 9%、5 0 5 %和 4 2 9%、35 7% ,两组间在 0、5、10d时差异具有非常显著性 (P <0 0 1)。 (2 )离断力 :Ⅰ组 ,0、5、10d分别为 (4 5± 0 4 )N、(6 6± 0 4 )N和 (10 0± 0 6 )N ;Ⅱ组为 (4 6± 0 6 )N、(5 8± 0 5 )和 (7 1± 0 6 )N。两组在 0天时基本相同 ,但Ⅰ组在 0至 5d和 5至 10d两时间段有较快增长(44 8%和 5 2 9% ) ,两组间在 5、10d时差异具有显著和非常显著性 (P <0 0 5和P <0 0 1)。 (3)组织病理学 :Ⅰ组在 10d时吻合口已由结缔组织基本修复 ,胰腺残端断面已基本由黏膜上皮覆盖。而Ⅱ组则由肉芽组织不完全修复 ,胰腺残端断面尚无上皮再生。　结论　捆绑组 (Ⅰ组 )吻合口强度更强 ,愈合更快。     

特发性无、少精子症病人精浆中性激素水平的测定及意义

目的 :通过测定特发性无、少精子症病人精浆中的性激素水平 ,比较分析精浆性激素与无、少精子症的关系。　方法 :特发性无、少精子症男性各 5 0例 ,正常对照 5 0例。精液常规分析判断精子密度 ,化学发光技术测定精浆性激素水平。　结果 :特发性无、少精子症组黄体生成素 (LH)分别为 (5 .19± 0 .6 7)IU/L和 (4.77± 0 .6 8)IU/L ,与正常组 (2 .19± 0 .2 2 )IU/L相比 ,特发性无精子症组差异有极显著性 (P <0 .0 1) ,特发性少精子症组与正常组相比差异有显著性 (P <0 .0 5 ) ;卵泡刺激素 (FSH)分别为 (1.90± 0 .79)IU/L和 (2 .2 7± 0 .2 5 )IU/L ,与正常组 (1.6 1± 0 .14)IU/L相比 ,差异均有显著性 (P <0 .0 5 ) ;泌乳素 (PRL)分别为 (6 .2 5± 0 .34 )ng/ml和 (6 .33±0 .5 1)ng/ml,与正常组 (6 .36± 0 .32 )ng/ml相比差异均无显著性 (P >0 .0 5 ) ;睾酮 (T)分别为 (1.5 1± 0 .12 )ng/ml和 (1.6 8± 0 .71)ng/ml,与正常组 (1.83± 0 .0 9)ng/ml相比 ,特发性无精子症组差异有显著性 (P <0 .0 5 ) ,特发性少精子症组差异无显著性 (P >0 .0 5 ) ;T/LH的比值分别为 0 .2 9± 0 .0 4和 0 .35± 0 .0 9,与对照组 0 .84± 0 .2 0相比 ,差异均有显著性 (P <0 .0 5 )。　结论 :特发性无、少精子症病人 ,精浆     

宫腔镜下刮匙刮除及电切除子宫内膜息肉的比较研究

目的　比较宫腔镜下刮匙刮除术 (D&C)与电切除术 (HE)两种术式治疗子宫内膜息肉的效果。　方法　子宫内膜息肉 86例分为两组 ,其中 32例行D&C术 ,5 4例行HE术 ,比较手术时间、术中术后并发症和息肉的复发情况。　结果　两组的手术时间分别为 (8 5± 4 2 )min、(9 0± 3 1)min ,差异无显著性 (t=0 6 32 ,P =0 5 2 9) ;息肉复发例数分别为 9例 (36 0 % )、3例 (7 5 % ) ;复发时间分别是 (5 3± 3 5 )月、(11 2± 4 8)月 ,两组比较均有显著性差异 (χ2 =6 5 16 ,P =0 0 11;t=6 0 5 8,P =0 0 0 0 )。　结论　子宫内膜息肉电切除术较息肉刮除术的复发率低 ,复发时间晚。     

聚丙烯酰胺水凝胶注入兔体的免疫效应研究

目的　观察注射性聚丙烯酰胺水凝胶 (PAMHG)注入实验兔体的免疫效应。方法　采用间接免疫荧光法或双抗体夹心ELISA法 ,监测PAMHG注入兔体前后T淋巴细胞亚群、NK细胞活性、IL 2和sIL 2R表达水平。结果　PAMHG注入兔体前 ,CD3+ 和CD4 + T淋巴细胞表达水平分别为(17.8± 5 .9) %和 (9.6± 3.5 ) % ;PAMHG注入兔体后 3个月 ,表达水平分别为 (2 4 .3± 5 .6 ) %和 (15 .8± 4 .7) %。注入前后比较有显著差异 (P <0 .0 1)。 3个月后表达水平逐渐下降 ,与术前比较差异无显著意义 (P >0 .0 5 )。PAMHG注入兔体前 ,CD8+ T淋巴细胞表达水平为 (6 .2± 2 .4 ) % ,与注入后 3个月为 (8.5± 4 .2 ) %比较仅略有上升 ,两者比较P >0 .0 5。注入兔体前、后CD4 + CD8+ 比值均在正常范围(1～ 2 )。NK细胞活性仅于注入兔体 1个月为 (2 5 .3± 6 .8) % ,较注入前 (18.0± 9.7) %升高 (P <0 .0 5 ) ,俟后NK细胞活性逐渐下降 ,与注入前比较差异无显著性意义 (P >0 .0 5 )。IL 2和sIL R表达水平于注入兔体前后差异无显著性意义 (P >0 .0 5 )。结论　PAMHG用作软组织填充剂 ,仅在机体内引起短时异物排斥 ,可渐与组织相容 ,不会引起严重免疫功能失调     

缺血预处理对兔离体心脏长期保存的心肌保护作用

目的　观察缺血预处理对离体心脏长期保存的心肌保护作用。方法　将 2 4只家兔随机分为 4组 ,每组 6只 ,分成空白对照组、预处理组、保存组和预处理后保存组。离体兔心脏用Langendorff装置灌注稳定后 ,分别给予缺血预处理后再灌注、心脏保存 1 8h后再灌注及缺血预处理后再经 1 8h保存后再灌注 60min ,观察左室收缩功能的恢复率、冠脉回流液中碱性磷酸激酶(CK)、乳酸脱氢酶 (LDH)的浓度以及心肌形态结构改变。结果　预处理组同空白对照组相比 ,各项指标差异无显著性 (P >0 .0 5)。单纯保存组同对照组相比 ,左室收缩功能明显减弱 ,冠脉回流液中心肌酶的漏出明显增加 ,光镜及电镜观察心肌损伤严重。而经预处理后再保存组 ,左室收缩功能的恢复率较单纯保存组有明显提高 [(51 .9± 7.5) %比 (36 .6± 4 .9) % ,P <0 .0 5] ,心肌酶漏出明显减少 [CK :(31 2± 52 )IU/L比 (642± 1 0 8)IU/L ;LDH :(2 9± 9)IU/L比 (76± 1 0 )IU/L ,P <0 .0 5] ,光镜及电镜观察 ,心肌损伤程度明显减轻。结论　缺血预处理过程本身对心肌细胞无明显损伤 ,是比较安全的 ;缺血预处理对离体心脏长期保存有明显的保护作用     

输尿管口附近膀胱肿瘤的手术处理

目的　总结输尿管口附近膀胱肿瘤的手术治疗经验。　方法　需行输尿管再植的膀胱肿瘤患者 4 2例 ,随机分为两组 :A组 2 0例 ,绕输尿管口膀胱壁舌状切除结合改良Huctch Ⅱ输尿管移植 ;B组 2 2例 ,膀胱外寻找并离断输尿管 ,膀胱部分切除术后将输尿管再植于膀胱。对两组手术时间、手术失血量、术后引流量、近期并发症、膀胱输尿管返流、输尿管梗阻及肿瘤复发率进行对比分析。　结果　A组手术时间 (6 0 .5± 18.5 )min、手术失血量 (30 .7± 12 .4 )ml、术后引流量 (5 0 .6± 17.8)ml;B组手术时间 (15 0 .9± 2 2 .4 )min、手术失血量 (2 2 0 .5± 2 8.2 )ml、术后引流量 (2 80 .6± 5 8.9)ml;以上三项指标两组之间差异有显著性意义 (P <0 .0 0 1)。近期并发症A组 2例 ,B组 8例。两组间比较差异有显著性意义 (P <0 .0 5 ) ;膀胱输尿管返流、输尿管梗阻及肿瘤复发率两组比较差异无显著性 (P >0 .0 5 )。　结论　绕输尿管口膀胱舌状切除结合改良Huctch Ⅱ输尿管移植手术效果良好 ,手术并发症少 ,操作简单 ,值得推荐。     

骨质疏松股骨颈经CCPC强化后螺钉固定的生物力学研究

目的　评价不同直径螺钉固定时添加复合磷酸钙骨水泥 (CCPC)对骨质疏松股骨颈生物力学变化的影响。方法　采用 2 4个股骨上段标本 ,随机分为三组 :深螺纹强化组、中等螺纹强化组和浅螺纹强化组。结果　三组均灌注CCPC ,深螺纹组、中螺纹组和浅螺纹组的螺钉初始松动加载力分别为(32 8 9± 34 9)N、(335 7± 2 6 6 )N、(2 84 8± 2 5 9)N ;最大轴向拔出力分别为 (36 9 5± 2 1 9)N、(36 4 0± 17 5 )N、(30 5 6± 2 4 5 )N ,深螺纹组、中螺纹组均和浅螺纹组差异有显著性意义 (P <0 0 5 )。结论　螺钉直径与骨质疏松股骨颈强化后的稳定性有关。     

被动吸烟对大鼠骨密度与骨代谢的影响

目的　探讨大鼠骨质疏松与吸烟的关系。方法　将 32只Wister大白鼠随机分成 4组 ,分别予以不吸烟、被动吸烟 2、3和 4个月 ,测量大鼠骨密度并检测血清骨钙素、尿钙与尿肌酐。结果　吸烟 2个月与 3个月组大鼠骨密度与对照组差异无显著性 (P >0 .0 5) ;吸烟 4个月组大鼠活体腰椎总体和各单个腰椎的骨密度 (g/cm2 )分别为 0 .1 791± 0 .0 0 96、0 .1 774± 0 .0 0 92、0 .1 76 7± 0 .0 1 1 0和 0 .1 799± 0 .0 1 4 0 ,相应的离体骨密度 (g/cm2 )分别为 0 .2 0 5 4± 0 .0 0 88、0 .2 0 1 5± 0 .0 0 72、0 .2 0 94± 0 .0 1 1 2和 0 .2 1 6 9± 0 .0 1 4 0 ,均显著低于对照组 (P <0 .0 1或P <0 .0 5) ,离体股骨和胫骨整体及各感兴趣区骨密度也显著低于对照组 (P <0 .0 1或P <0 .0 5) ,全身骨密度两组差异无显著性 (P >0 .0 5) ;4组大鼠血清骨钙素水平差异无显著性 ;吸烟 2个月组与对照组尿Ca/Cr差异无显著性 ,吸烟 3个月与 4个月组大鼠尿Ca/Cr分别为 0 .787± 0 .2 2 6和0 .781± 0 .2 1 7,显著低于对照组 (P <0 .0 5) ,且吸烟 4个月组大鼠骨密度除全身骨密度外均与尿Ca/Cr呈负相关。结论　吸烟使骨吸收增强从而导致骨丢失、发生骨质疏松 ,尿Ca/Cr较骨密度对骨丢失更敏感     

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.