依托咪酯乳剂诱导时雷米芬太尼抑制气管插管反应的效应室靶浓度

目的 测定依托咪酯乳剂诱导时雷米芬太尼抑制气管插管反应的效应室靶浓度(EC50和EC95).方法 选择23例ASAⅠ或Ⅱ级全麻择期手术患者靶控输注(TCI)雷米芬太尼,血浆浓度与效应室浓度达到平衡后静脉注射依托咪酯乳剂0.3 mg/kg,患者意识消失后静脉注射琥珀胆碱行气管插管.气管插管后2 min内最高的SBP和/或HR高出基础值15%为气管插管反应阳性.雷米芬太尼靶浓度按改良序贯法增加或减少0.5 ng/ml.用概率单位回归分析法计算出雷米芬太尼抑制气管插管反应的EC50、EC95及相应的95%可信区间(CI).结果 雷米芬太尼抑制气管插管反应的EC50为3.06 ng/ml,95%CI为2.56～3.47 ng/ml;相应的EC95为3.85 ng/ml,95%CI为3.45～6.64ng/ml.结论 复合依托咪酯0.3 mg/kg诱导时雷米芬太尼抑制气管插管反应的EC50和EC95分别为3.06 ng/ml和3.85 ng/ml.     

雷米芬太尼靶控输注在老年患者全麻诱导中的应用

目的 比较雷米芬太尼不同血浆靶控浓度在老年患者全麻诱导中的应用.方法 老年患者(≥65岁,A组)和青壮年患者(<60岁,B组)各40例,每组又随机均分为四个亚组:A1、A2、A3、A4、B1、B2、B3、B4,分别输注雷米芬太尼靶控血浆浓度为1、2、3、4 ng/ml,5 min后开始靶控输注丙泊酚(血浆浓度2.5μg/ml),10 min后给维库溴铵0.1 mg/kg,2 min后行气管插管.记录各时刻患者的BP、HR、Grant气管插管评分、BIS及血管活性药物的使用及不良反应的发生情况.结果 A组相对于同浓度B组阿托品和麻黄碱的使用例数增多(P<0.05),A1、A2、A3组使用阿托品的例数少于A4组(P<0.05),A2、A3组使用硝酸甘油的例数分别少于B2、B3组(P<0.05),B2、B3组多于B4组(P<0.05).各浓度的雷米芬太尼均引起BIS的轻度下降,而雷米芬太尼输注后BP虽有轻度下降,但差异无统计学意义.插管评分,B1组明显高于其他亚组(P<0.05).相对于气管插管前即刻,气管插管后1 min与切皮后2 min各组BP均有上升,A3、A4和B4组BP上升、HR增快的幅度较小.结论 靶控输注雷米芬太尼与丙泊酚用于老年患者全麻诱导,两者靶控浓度分别为2～3 ng/ml和2.5μg/ml比较合理,诱导效果满意,且能维持血流动力学稳定.     

雷米芬太尼靶控输注抑制全麻拔管期心血管不良反应的剂量探讨

目的探讨雷米芬太尼靶控输注(TCI)拔管期有效抑制心血管反应的半数有效血浆浓度(EC50)。方法择期全麻下行腹腔镜胆囊切除术(LC)成人患者40例,按照序贯法TCI血浆浓度分别为0.6、0.8、1.0、1.2和1.4 ng/ml的雷米芬太尼,初始靶浓度为1.0 ng/ml,若患者拔管时SBP高于基础值的20%或HR快于100次/分,或拔管时出现呛咳、躁动,则下一例患者采用高一级浓度的雷米芬太尼TCI;反之则采用低一级浓度的雷米芬太尼TCI。计算全麻拔管期有效抑制心血管反应的雷米芬太尼EC50及其95%可信区间(CI)。结果TCI雷米芬太尼抑制心血管反应的EC50为1.03 ng/ml,其95%CI为0.97~1.09 ng/ml。结论LC全麻拔管期有效抑制心血管反应的雷米芬太尼EC50为1.03 ng/ml。     

雷米芬太尼复合丙泊酚靶控输注对肺叶切除患者术中血流动力学的影响

目的观察复合丙泊酚靶控输注(TCI)时雷米芬太尼对肺叶切除术中患者血流动力学的影响,探讨雷米芬太尼用于开胸手术中安全、有效的血浆靶浓度。方法肺叶切除术患者40例,ASAⅡ级,年龄40~60岁,体重52~74kg。随机均分为R6组和R8组。麻醉诱导雷米芬太尼血浆靶浓度分别为6、8ng/ml,丙泊酚血浆靶浓度设定为3μg/ml,术中两组雷米芬太尼血浆靶浓度不变。HemosonicTM100监测各项血流动力学指标,记录患者基础值(T0)、切皮即刻(T1)、断肋即刻(T2)、开胸探查即刻(T3)、关胸即刻(T4)、缝皮完毕即刻(T5)时MAP、HR、心输出量(CO)、每搏量(SV)、血流峰速度(PV)、血流加速度(ACC)、左室射血时间(LVET)、体循环血管阻力(TSVR)及脑电双频指数(BIS)。结果与T0比较,R6组在T1、T2、T4、T5各时点血流动力学指标波动较小;组间比较,R6组T3时MAP、HR、TSVR高于R8组(P<0.05);两组T1~T5时BIS均低于T0时(P<0.01),T2、T3时R8组BIS低于R6组(P<0.05)。结论在胸科手术中复合丙泊酚3μg/ml靶控输注,雷米芬太尼血浆靶浓度可采用初始6ng/ml,在较强手术刺激时调至8ng/ml,以确保血流动力学稳定,从而获得较为满意的麻醉效果。     

丙泊酚复合麻醉时神经外科手术患者雷米芬太尼的量效关系

目的 探讨丙泊酚复合麻醉时神经外科手术患者雷米芬太尼的量效关系.方法 择期额颞部开颅手术患者15例,先行靶控输注(TCI)阿泊酚,设定效应室靶浓度为3 μg/ml,维持PErCO2为35～45 mmHg,待达到丙泊酚靶浓度后开始TCI雷米芬太尼,设定效应室靶浓度分别为2、3、4、5、6、7、8ng/ml,雷米芬太尼达不同效应事浓度时给予50 mA、50 Hz、5 s强直电刺激,记录电刺激前后BP、HR及脑电双频指数(BIS)的变化.结果 随着雷米芬太尼效应室浓度的增加,BP逐渐降低,HR逐渐减慢(P<0.05或P<0.01);强直电刺激后BP升高幅度、HR加快幅度也逐渐降低(P<0.05或P<0.01).雷米芬太尼效应室浓度达(5.13±0.92)ng/ml时,强直电刺激后MAP升高幅度<5%,95%可信区间为3.33～6.93 ng/ml.与基础值比较,随着雷米芬太尼的效应室浓度逐渐增加,BIS逐渐降低(P<0.01),电刺激前后BIS无明显变化.结论 随雷米芬太尼效应室浓度的增加,镇痛强度逐渐增强,电刺激-循环反应逐渐减弱;雷米芬太尼效应室浓度大于(5.13±0.92)ng/ml时,95%可信区间为3.33～6.93ng/rnl,50 mA强直电刺激-循环反应变化小再明显.     

靶控输注雷米芬太尼对脑电双频指数的影响

目的研究不同靶浓度的雷米芬太尼对脑电双频指数（BIS）的影响。方法60例择期行全麻手术的病人随机分成R0、R2、R4、R6四组,每组15例。病人进入手术室静卧5min取得基础数据后,给予血浆靶浓度为3μg／ml的丙泊酚,5min后依分组情况分别给予血浆靶浓度为0、2、4、6ng／ml的雷米芬太尼,3min后行气管插管,并记录数据至气管插管后5min。所有病人均未给予术前药,病人意识消失后给予0．1mg／kg的维库溴铵,研究中应用辅助或机械通气以维持PET CO2在35～45mmHg。记录每分钟的MAP、HR、BIS,并将病人人室后（T0）、给雷米芬太尼前（T1）、气管插管前（T2）及气管插管后5min内的最大值（T3）进行统计分析。结果2～6ng／ml的雷米芬太尼对BIS没有影响。R2组病人气管插管后存在插管反应,BIS明显升高,BIS变化趋势与MAP、HR变化趋势相一致。结论雷米芬太尼对BIS没有影响。BIS可以用来指导丙泊酚的用量,4ng／ml的雷米芬太尼是较佳的气管插管剂量。     

丙泊酚-雷米芬太尼靶控输注在心脏手术中的应用

目的 观察丙泊酚-雷米芬太尼靶控输注(TCI)在心脏瓣膜置换术和冠状动脉旁路移植术中使用的安全性、有效性以及对术后恢复的影响.方法 择期心脏手术患者150例,以丙泊酚TCI、雷米芬太尼3～5μg/kg诱导,丙泊酚-雷米芬太尼2～8 ng/ml TCI维持,维持脑电双频指数(BIS)于50±10.观察术中血流动力学指标和术后恢复情况.结果 所有患者术中血流动力学平稳,术后恢复良好,无术中知晓.结论 雷米芬太尼[效应部位浓度(Ce)2～8 ng/ml]复合丙泊酚[血浆浓度(Cp)1～2μg/ml]用于心脏手术的麻醉安全有效,血流动力学平稳,有利于术后早期气管拔管.     

靶控输注丙泊酚和雷米芬太尼在意识消失和对疼痛刺激反应时的相互关系

目的探讨靶控输注(TCI)丙泊酚和雷米芬太尼的相互关系及对脑电双频指数(BIS)的影响。方法全身麻醉患者100例,根据丙泊酚不同血浆靶浓度随机均分为五组:P1.5组,1.5μg/ml;P2组,2μg/ml;P2.5组,2.5μg/ml;P3组,3μg/ml;P3.5组,3.5μg/ml。待血浆浓度和效应室浓度达到平衡后TCI雷米芬太尼,以血浆浓度0ng/ml为起点,每30秒增加0.3ng/ml,直至患者意识消失及对疼痛刺激(50Hz,80mA,0.25ms强直刺激)无体动反应。记录患者在不同丙泊酚血药浓度下意识消失时和对疼痛刺激无反应时雷米芬太尼的血浆浓度(Cp)和效应室浓度(EC)。结果意识消失时雷米芬太尼Cp50从P1.5组至P3.5组分别为5.0、3.0、2.1、1.2、0ng/ml;疼痛刺激无反应时雷米芬太尼Cp50从P1.5组至P3.5组分别为5.4、4.3、3.9、3.5、3.0ng/ml;疼痛刺激无反应时与意识消失时BIS值的差异无统计学意义。结论BIS值变化与丙泊酚血药浓度呈反比关系,雷米芬太尼对BIS值影响不大。BIS值50～60可以作为丙泊酚和雷米芬太尼静脉复合麻醉时监测意识消失的良好指标。     

丙泊酚血浆靶控输注与不同镇痛药物用于人工流产术的麻醉效果

目的比较丙泊酚血浆靶控输注分别复合芬太尼或舒芬太尼单次静脉注射及雷米芬太尼血浆靶控输注用于人工流产术的效果。方法选择120例行人工流产术的患者,随机分为芬太尼单次静脉注射组(F组)、雷米芬太尼血浆靶控输注组(R组,靶浓度为4ng/ml)和舒芬太尼单次静脉注射组(S组),分别复合丙泊酚血浆靶控输注(靶浓度为4μg/ml)行静脉全麻,观察起效时间、恢复时间、准确定向时间、术中体动(程度和次数)、镇痛效果、呼吸抑制、HR、MAP、SpO2变化及术后并发症等。结果R组麻醉起效时间显著低于F组和S组(P<0·01),麻醉恢复时间显著高于F组和S组(P<0·01),R组的丙泊酚总用量、吸宫时术中最低SpO2、术中体动及术后恶心呕吐、嗜睡均低于F组和S组(P<0·05,P<0·01),R组的呼吸抑制显著高于F组和S组(P<0·01)。结论丙泊酚血浆靶控输注复合雷米芬太尼血浆靶控输注的麻醉方法用于人工流产术,其镇痛效果优于丙泊酚血浆靶控输注复合芬太尼或舒芬太尼单次静脉注射的麻醉方法,但要注意雷米芬太尼呼吸抑制作用较强的特点。     

异丙酚麻醉下瑞芬太尼抑制病人气管插管和切皮时心血管反应的效应室靶浓度

目的测定异丙酚麻醉期间瑞芬太尼抑制病人气管插管和切皮时心血管反应的效应室靶浓度(EC50和EC95)。方法择期全麻手术病人60例,ASAⅠ或Ⅱ级,年龄加～65岁,体重40～75 kg,随机分为6组(n=10):瑞芬太尼靶控输注(TCI),血浆靶浓度分别为1、2、3、4、5、6 ng/ml;异丙酚TCI,效应室靶浓度均为4.0μg/mI。病人意识消失后静脉注射维库溴铵0.15 mg/kg,气管插管。插管后2 min暂停瑞芬太尼TCI,切皮前10 min再以诱导时相同浓度瑞芬太尼TCI。记录入室安静时(基础值)、诱导后最低、插管后2 min内最高、切皮前1 min、切皮后2 min内最高的平均动脉压(MAP)和心率(HR)。MAP和HR诱导后最低值与插管后2 min内最高值、切皮前1 min与切皮后2 min内最高值比较升高>15%为心血管阳性反应。采用Probit法计算瑞芬太尼EC50和EC95。结果瑞芬太尼抑制气管插管时心血管反应的EC50为4.41 ng/ml,95%可信区间(95%CI)为3.97～5.05 ng/ml;相应的EC95为6.42 ng/ml,95%CI为5.54～8.09 ng/ml。瑞芬太尼抑制切皮时心血管反应的EC50为2.05 ng/ml,95%CI为1.36～2.59 ng/ml;相应的EC95为3.89 ng/ml,95%CI为3.20～5.71 ng/ml。结论异丙酚效应室靶浓度为4.0μg/ml时,靶控输注瑞芬太尼抑制病人对气管插管和切皮诱发的心血管反应呈剂量依赖性,其效应室EC50分别为4.41 ng/ml和2.05 ng/ml。     

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.