腹腔镜手术病人咪达唑仑-芬太尼-异丙酚麻醉诱导的优化配伍方案

目的 采用权重配方法探讨腹腔镜手术病人咪达唑仑、芬太尼、异丙酚复合麻醉诱导的优化配伍方案。方法选择ASAⅠ或Ⅱ级择期腹腔镜手术病人60例，男34例，女26例，年龄31～55岁。诱导药物的低效量和足量分别确定为咪达唑仑0．02、0．06mg／kg，芬太尼2、6μg／kg，异丙酚0．5、1．5mg／kg。根据权重配方法，将病人随机分配至3种药物不同剂量组合的6个配伍组（n=10）。连续监测脑电双频谱指数（BIS）、心率（HR）、平均动脉压（MAP）、脉搏血氧饱和度（SpO2）。各组依次静脉注射相应剂量咪达唑仑、芬太尼、异丙酚和罗库溴铵0．6mg／kg行麻醉诱导和气管插管。记录诱导前即刻、异丙酚注入后1、2min、插管即刻、插管后1、3、5、7min的BIS、MAP及HR。按权重配方法的剂量优化原则评判复合药效，分析各组份药的重要程度及相互作用的性质。结果以BIS为评价指标，当咪达唑仑0．06mg／kg、芬太尼5μg／ks、异丙酚1．0mg／kg配伍时，异丙酚为主药，异丙酚与咪达唑仑和芬太。尼具有相加性作用；以MAP为评价指标，当咪达唑仑0．06mg／kg、芬太尼5μg，kg、异丙酚1．5mg／kg配伍时，异丙酚为主药，异丙酚与咪达唑仑具有协同性作用，异丙酚与芬太尼具有相加性作用；以HR为评价指标，当咪达唑仑0．06mg／kg、芬太尼5μg／kg、异丙酚1．0mg／kg配伍时，芬太尼为主药，异丙酚与咪达唑仑和芬太尼具有协同性作用。结论腹腔镜手术病人咪达唑仑、芬太尼、异丙酚复合麻醉诱导在维持镇静方面为相加作用，在维持血液动力学稳定方面为协同作用；优化配伍方案为咪达唑仑0．06mg／kg、芬太尼5μg／kg、异丙酚1．5mg／kg。     

全麻复合硬膜外阻滞用于高龄患者腹腔镜直肠癌手术的观察

为评价全麻复合硬膜外阻滞在高龄患者腹腔镜直肠癌根治术中对循环功能及用药量的影响,选择70岁以上择期行腹腔镜直肠癌根治术患者40例,ASAⅠ、Ⅱ级,随机分为全麻组（G组）20例;全麻复合硬膜外阻滞组（GA组）20例。两组全麻诱导方法：咪哒唑仑0．04mg／kg,芬太尼3μg／kg,依托咪酯0．2～0．3mg／kg,顺阿曲库胺0．15～0．20mg／kg。GA组于诱导前取L1-2硬膜外腔穿刺置管,注入0．5％罗哌卡因5ml。术中每2h追加5～7ml。诱导前以PhilipsMP40监测仪监测平均动脉压（MAP）,心率（HR）,心电图（ECG）等生命体征,同时记录全麻用药量及术中知晓、术后躁动情况。结果显示,GA组气腹后,气管插管拔除前MAP、HR明显低于G组（P〈0．05）;GA组七氟烷用药浓度,顺阿曲库胺用药量低于G组（P〈0．05）。结果表明,高龄患者在腹腔镜直肠癌根治术中应用全麻复合硬膜外阻滞,可使患者术中循环稳定,全麻用药量减少,是一种安全可行的麻醉方法。     

不同剂量舒芬太尼对麻醉诱导时病人异丙酚效应室靶浓度及气管插管反应的影响

目的 观察在脑电双频谱指数（BIS）监测下不同剂量舒芬太尼对麻醉诱导时病人异丙酚效应室靶浓度（Ce）及气管插管反应的影响，以探讨舒芬太尼复合异丙酚麻醉诱导的合适用量。方法 择期全麻手术病人60例，ASAⅠ级或Ⅱ级，年龄20-60岁，体重45-80 kg，随机分为3组（n= 20），均静脉注射咪达唑仑0．05 mg／kg后开始靶控输注异丙酚（初始靶浓度为2μg／ml），同时分别静脉注射芬太尼3μg／kg（F组）、舒芬太尼0．3μg／kg（S1组）、舒芬太尼0．45μg／kg（S2组）。待病人意识消失后或BIS降至75以下时静脉注射维库溴铵0．12 mg／kg，BIS降至55以下时进行气管插管，机械通气。调整异丙酚靶浓度维持BIS 40-60。记录入室时（基础值）、气管插管前即刻、插管后即刻、插管后3、5、10、15 min时BP、MAP、HR、BIS及Ce。结果 与F组和S1组比较，S2组插管后即刻和插管后3、5、10、15min时Ce降低（P〈0．05），但F组和S1组各时点比较差异无统计学意义（P〉0．05）。与基础值比较，F组和S1组插管后即刻和插管后3 min时BP、MAP和HR增加（P〈0.05）。与S2组比较，F组和S1组插管后即刻和插管后3 min时BP、MAP和HR增加（P〈0．05）。F组和S1组各时点BP、MAP和HR比较差异均无统计学意义（P〉0．05）。结论 病人在靶控输注异丙酚麻醉诱导时，舒芬太尼抑制气管插管心血管反应的效价是芬太尼的7倍。     

经皮穴位电刺激对全麻患者异丙酚效应室靶浓度和芬太尼用量的影响

目的 探讨经皮穴位电刺激对全麻患者异丙酚效应室靶浓度和芬太尼用量的影响.方法 择期全麻下行上腹部手术患者40例,随机分为2组(n=20),异丙酚复合全麻组(P组),穴位电刺激+异丙酚复合全麻组(EP组)从麻醉诱导前30 min至术毕行持续双侧内关穴、足三里穴电刺激,以刺激频率2 Hz和100 Hz的疏密波进行交替刺激,刺激强度8～12 mA.麻醉诱导:两组均静脉注射咪达唑仑0.03 mg/kg、芬太尼1.5μg/kg、维库溴铵0.12 mg/kg,靶控输注异丙酚(血浆靶浓度2.5 μg/ml);麻醉维持:以0.1μg/ml幅度增加或降低异丙酚效应室靶浓度,维持BIS 45～55,间断静脉注射维库溴铵2 mg和芬太尼0.05～0.1 mg.于气管插管前、气管插管后、切皮前、切皮后、术中探查、术毕时记录HR、MAP和异丙酚效应室靶浓度,记录芬太尼用量.于麻醉诱导前(基础状态)、电刺激30 min、切皮后、术中探查、术毕时采集外周静脉血样,测定血清血管紧张素Ⅱ和皮质醇的浓度.结果 EP组异丙酚效应室靶浓度和芬太尼用量低于P组(P＜0.01);两组MAP和HR均波动在正常范围;两组间各时点血清血管紧张素Ⅱ和皮质醇浓度差异无统计学意义(P＞0.05).与基础值比较,EP组电刺激30 min时血清血管紧张素Ⅱ和皮质醇浓度下降(P＜0.05),P组术中探查时血管紧张素Ⅱ和皮质醇浓度升高(P＜0.05或0.01).结论 经皮穴位电刺激可降低全麻患者异丙酚效应室靶浓度,减少芬太尼用量.     

气管内硬膜外联合麻醉下的超前镇痛

目的 研究气管内硬膜外联合麻醉下，硬膜外给药时间不同、全麻诱导药物不同对术后镇痛产生的影响。方法 开腹行切除肝癌、胃癌的病人120例，随机分为A、B、C、D4组，每组30例。A组：在T8-9经硬膜外注入1％利多卡因和0．25％布比卡因混合液6～8ml，再经硬膜外注入含吗啡2mg、氟哌利多2．5mg的生理盐水10ml；全身麻醉诱导药物为芬太尼3μg／kg，异丙酚1～1．5mg／kg，琥珀胆碱2mg／kg。B组：诱导药物中不使用芬太尼，用利多卡因1～1．5mg／kg代替，术中也不使用芬太尼，其余条件同A组。C组：在T8-9行硬膜外穿刺，之后行全身麻醉诱导，诱导药物为芬太尼3μg／kg，异丙酚2—2．5mg／kg，琥珀胆碱2mg／kg，必要时可加芬太尼2～3μg／kg。切皮后90min，经硬膜外注入1％利多卡因和0．25％布比卡因6～8ml，再经硬膜外注入含吗啡2mg、氟哌利多2．5mg的生理盐水10ml。D组：诱导药物中不使用芬太尼，用利多卡因1～1．5mg／kg代替，术中也不使用芬太尼，其余条件同C组。分别于术毕后4、8、24、48h观察视觉模拟评分（VAS）、镇痛药消耗量、恶心、呕吐、瘙痒等指标。结果 A组的药物消耗量最少、镇痛效果最好；B组和C组次之；D组的药物消耗量最大，镇痛效果最差。结论 硬膜外复合气管内麻醉时，硬膜外麻醉与芬太尼同时使用，术后镇痛效果最好。     

Ebstein畸形矫治术的合理麻醉处理

目的 总结Ebstein畸形矫治术的麻醉处理经验。方法Ebstein畸形矫治术的麻醉处理19例。成人患者术前口服安定10mg,肌注东莨菪碱0．3mg,吗啡10mg;而12岁以下小孩诱导前肌注氯胺酮6～7mg／kg、东莨菪碱0．01mg／kg。全麻诱导静脉注射咪唑安定0．01—0．03mg／kg,依托咪酯0．1～0.3mg／kg,芬太尼5-10μg／kg,哌库溴铵O．1mg／kg麻醉诱导,吸入1MAC异氟醚。持续静脉输注异丙酚0.8—2μg／ml;间断给予芬太尼5～10μg／kg,哌库溴铵0．05mg／kg。结果麻醉平稳,所有患者术后症状明显改善,围术期无一例死亡。结论采用复合麻醉药物的处理．对Ebstein畸形矫治术具有良好的麻醉效果。     

异丙酚复合芬太尼妇科门诊手术麻醉中熵指数的应用

目的：观察妇科门诊异丙酚复合芬太尼麻醉中熵指数-反应熵和状态熵的变化。方法：ASAⅠ-Ⅱ级妇科门诊无痛刮宫或人流患者30例．入室后常规监测,然后静脉给予芬太尼（1μg·kg）和异丙酚（2-2．5mg·kg）。记录麻醉前和麻醉后直至苏醒期间RE、SE、MAP、HR、SP02,OAA／S。结果：与麻醉前相比,麻醉后1、2,3．4、5,6、7min各观察点MAP、RE．SE、OAA／S均下降（p〈0．05或0．01）;HR的变化幅度正常;与SE相比RE在各观察点均升高（p〈0．01）。结论：熵指数能较好地反映异丙酚复合芬太尼麻醉的深度。     

异丙酚单用与复合芬太尼在隆鼻术中麻醉效果比较

目的:比较异丙酚单独或复合芬太尼用于无痛隆鼻术中的麻醉效果。方法:就医者40例,随机分配为A组(异丙酚)和B组(异丙酚复合芬太尼),每组各20例。A组静注异丙酚1.5～2mg.kg-1使其入睡后手术开始,术中异丙酚以4～6mg.kg-1.h-1微泵维持。B组先静脉注射芬太尼0.1mg,随后麻醉过程同A组。记录术中体动反应次数、异丙酚用量,记录麻醉前、麻醉后2mi n、5mi n、10mi n、手术结束时的MAP、HR、RR和SPO2,记录麻醉过程中发生的不良反应。结果:B组术中体动反应次数和异丙酚用量都明显少于A组(P<0.01),B组麻醉后2mi n时MAP、HR、RR和SPO2明显下降(P<0.05或P<0.01),但在麻醉后5mi n时都恢复正常。结论:在无痛隆鼻术麻醉中复合芬太尼未明显增加麻醉不良反应,但增强了镇痛效果,能明显减少体动反应,减少异丙酚使用量,降低治疗费用。     

芬太尼对罗哌卡因低位硬膜外麻醉效果的影响

目的探讨芬太尼对罗哌卡因行低位矿膜外麻醉时的麻醉效果及其量效关系的影响。方法60例ASAI-Ⅱ级择期腰椎间盘手术成年病人，随机分为A、B、C三组，每组20例，均于T12／L1椎间隙行硬膜外腔穿刺，向下置管3cm。硬膜外局麻药配方分别为：A组0．5％罗哌卡因、B组0．5％罗哌卡因＋芬太尼2mg／L、C组0．5％罗哌卡因＋芬太尼4mg／L。观察记录麻醉效果，持续时间，运动阻滞程度及副作用等。应用Probit半数效量回归法分别计算三组ED50值和ED95值。结果三组配方60例病人在腰椎手术中行硬膜外麻醉有58例获得满意效果。罗哌卡因在C组ED50值和ED95值均明显小于A组（P〈0．05）。C组麻醉持续时间较A、B组长，Bromage评级较A、B组低（P〈0．05），三组间不良反应发生例数无统计学意义（P〉0．05）。结论低位硬膜外麻醉时芬太尼能明显增强罗哌卡因麻醉效果，延长麻醉作用时间，并减轻下肢运动阻滞程度，其中C组效果最佳。     

切口浸润罗哌卡因对全麻下甲状腺手术患者血流动力学的影响

目的：观察0．5％罗哌卡因局部切口浸润对患者在全麻下行甲状腺手术时的血流动力学的影响。方法：采用随机、双盲、对照设计，将40例甲状腺择期手术患者分为罗哌卡因组（A组）和生理盐水组（B组），每组各20例．全麻诱导后气管插管，持续吸入异氟醚维持麻醉直至手术结束．术中使用Bls监测麻醉深度，维持在50～60之间．切皮前10分钟分别用05％罗哌卡因10ml和09％生理盐水10ml进行切口局部皮下浸润，两组溶液均未加入肾上腺素。记录手术前、切口浸润即刻．切皮即刻及其后1分钟．2分钟、5分钟、缝合皮下组织、缝合皮肤时的平均动脉压（MAP）和心率（HR）。结果：罗哌卡因组切皮后1分钟，2分钟、5分钟、缝合皮下组织、缝合皮肤时的MAP、HR均低于生理盐水组（P〈0．05）。结论；0.5％罗哌卡因切口浸润麻醉．有效地预防了早状腺手术患者在全麻手术时切皮、缝合皮下组织、缝合皮肤时血压和心率的升高。     

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.     

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.     

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.