不同全麻下腹腔镜结肠癌切除术病人围术期细胞免疫功能的比较

目的 比较在相同麻醉深度下不同全麻对腹腔镜结肠癌切除术病人围术期细胞免疫功能的影响.方法 择期行腹腔镜结肠癌切除术的病人90例,年龄40～64岁,体重50～85 kg,性别不限,ASA分级Ⅰ或Ⅱ级.采用分层随机法,将患者随机分为3组(n＝30):全凭静脉麻醉组(Ⅰ组)、吸入全麻组(Ⅱ组)和静吸复合全麻组(Ⅲ组).Ⅰ组静脉注射咪达唑仑、舒芬太尼和维库溴铵,TCI异丙酚和瑞芬太尼麻醉诱导;TCI异丙酚和瑞芬太尼,间断静脉注射维库溴铵维持麻醉.Ⅱ组吸入七氟醚麻醉诱导,吸人七氟醚,间断静脉注射维库溴铵维持麻醉.Ⅲ组静脉注射咪达唑仑、舒芬太尼和维库溴铵,TCI异丙酚和瑞芬太尼麻醉诱导,TCI异丙酚和瑞芬太尼,吸入七氟醚,间断静脉注射维库溴铵维持麻醉.术中采用Narcotrend指数监测麻醉深度,维持Narcotrend指数37 ～ 64.于麻醉诱导前30min(T0)、切皮后2 h(T1)、术毕(T2)和术后24 h(T3)时采外周静脉血样,采用流式细胞术测定T淋巴亚群CD3+、CD4+、CD8+和NK细胞的水平,计算CD4+/CD8+.结果 与T0时比较,Ⅱ组T2时CD3+、CD4+、CD4+/CD8+和NK细胞水平降低,Ⅲ组T2时NK细胞水平降低(P<0.05);与Ⅰ组比较,T2时Ⅱ组CD3+、CD4+、CD4+/CD8+和NK细胞水平降低,Ⅲ组NK细胞水平降低(P＜0.05);与Ⅲ组比较,T2时Ⅱ组CD3+和CD4+水平降低(P<0.05).结论 与吸入麻醉和静吸复合麻醉比较,静脉注射咪达唑仑、舒芬太尼和维库溴铵,TCI异丙酚和瑞芬太尼麻醉诱导,TCI异丙酚和瑞芬太尼,间断静脉注射维库溴铵维持麻醉对腹腔镜结肠癌切除术病人围术期细胞免疫功能的抑制程度低.     

地佐辛与咪达唑仑复合瑞芬太尼用于肝癌射频消融术患者麻醉效果的比较

目的比较地佐辛与咪达唑仑复合瑞芬太尼用于肝癌射频消融术患者麻醉的效果。方法选择2013年1月至2016年6月择期行经皮肝穿刺射频消融术的肝癌患者48例,随机分为地佐辛组(Ⅰ组)和咪达唑仑组(Ⅱ组),各24例。Ⅰ组静脉注射地佐辛负荷量0.8 mg/kg,Ⅱ组静脉注射咪达唑仑负荷量0.05~0.1 mg/kg。负荷量注射完毕后5 min静脉注射瑞芬太尼负荷量0.2μg/kg,然后静脉泵注瑞芬太尼0.05μg/(kg·min)并开始手术,术中根据血流动力学调整瑞芬太尼给药速度。记录诱导前、诱导后、热疗中、退针、苏醒5个时间点的平均动脉压(MAP)、心律(HR)和围术期的不良反应。结果两组诱导前、诱导后、热疗中、退针、苏醒5个时间点MAP(t=-1.929、0.315、1.380、1.604、0.463,P=0.061、0.754、0.176、0.117、0.063)和HR(t=-0.287、-0.280、-1.442、-0.766、0.683,P=0.775、0.781、0.158、0.448、0.489)的差异均无统计学意义。与Ⅱ组比较,Ⅰ组呼吸抑制发生率降低(χ~2=6.857,P=0.022),苏醒即刻疼痛程度评分、术后1 h疼痛评分差异有统计学意义(t=2.534、4.376,P=0.020、0.000)。结论肝癌射频消融术中地佐辛复合瑞芬太尼的麻醉效果优于咪达唑仑复合瑞芬太尼。     

不同麻醉诱导对患者眼内压影响的比较

目的 比较异丙酚、咪达唑仑或依托咪酯复合舒芬太尼麻醉诱导对患者眼内压(IOP)的影响.方法 拟在全麻下择期手术患者45例,年龄20-40岁,ASA分级Ⅰ或Ⅱ级,按照随机数字表法,将其随机分为3组(n=15):异丙酚组(P组)、咪达唑仑组(M组)和依托咪酯组(E组).麻醉诱导:P组、M组和E组分别静脉注射异丙酚2.0 mg/kg、咪达唑仑0.2 mg/kg及依托咪酯0.3 mg/kg后,依次静脉注射舒芬太尼0.2 μg/kg与顺阿曲库铵0.2 mg/kg,行气管插管术.于麻醉诱导前l min(T0)、气管插管前(T1)、气管插管后即刻(T2)、气管插管后1 min(T3)和2 min(T4)时测定IOP和MAP.结果 与P组比较,M组和E组低眼压发生率降低(P＜0.01);与E组比较,P组和M组高眼压发生率降低(P＜0.05).P组、M组和E组MAP与IOP的相关系数分别为0.831、0.889和0.806(p＜0.05),相关系数组间比较差异无统计学意义(P＞0.05).结论 咪达唑仑复合舒芬太尼麻醉诱导对IOP影响较小,MAP的波动程度是麻醉诱导引起IOP变化的主要因素.     

小儿开腹手术全凭静脉麻醉中小剂量瑞芬太尼复合咪达唑仑对术后拔管的影响

目的评价小儿开腹手术时小剂量瑞芬太尼合用咪达唑仑对术后拔管的影响。方法小儿开腹手术40例,全凭静脉麻醉。随机分为两组:Ⅰ组:异丙酚、维库溴胺、芬太尼静脉复合麻醉;Ⅱ组:咪达唑仑、异丙酚、维库溴胺、瑞芬太尼静脉复合麻醉,气管插管后行人工控制呼吸。对比观察两组患儿停药后自主呼吸恢复时间、术毕至气管导管拔除时间、拔管后5min不吸氧时的SpO2及术后恶心呕吐的发生率。结果停药后病人自主呼吸恢复时间及术毕至导管拔除时间:Ⅱ组明显短于Ⅰ组(P<0.01)。气管导管拔除后5min不给面罩吸氧时的SpO2:与麻醉诱导前比较Ⅰ组降低(P<0.05),Ⅱ组差异无显著性(P>0.05);Ⅱ组高于Ⅰ组(P<0.01)。术后恶心呕吐:Ⅰ组3例,Ⅱ组无1例发生,两组差异有显著性(P<0.05)。结论瑞芬太尼作为麻醉镇痛药,术毕自主呼吸恢复快,易于早期拔管,术后恶心呕吐发生率较低,适用于小儿开腹手术的麻醉。     

阿芬太尼与瑞芬太尼全凭静脉麻醉用于鼻内镜手术效果的比较

目的 比较全凭静脉麻醉(TIVA)应用阿芬太尼或瑞芬太尼对鼻内镜手术(ESS)效果的影响。方法 选择择期行鼻内镜手术的患者130例，男62例，女68例，年龄18～64岁，BMI 18～30 kg/m²,ASAⅠ或Ⅱ级。随机将患者分为两组：阿芬太尼组(A组)和瑞芬太尼组(R组)。A组麻醉诱导依次静脉注射咪达唑仑0.02 mg/kg、丙泊酚靶控输注(TCI)3μg/ml、阿芬太尼20μg/kg、罗库溴铵0.6 mg/kg,麻醉维持采用丙泊酚靶控输注复合阿芬太尼泵注。R组麻醉诱导依次静脉注射咪达唑仑0.02 mg/kg、丙泊酚TCI 3μg/ml、瑞芬太尼1μg/kg、罗库溴铵0.6 mg/kg,麻醉维持采用丙泊酚靶控输注复合瑞芬太尼泵注。记录术中高血压、心动过速、低血压、心动过缓等血流动力学不良反应发生情况，术后30、60 min、24 h的疼痛程度，拔管时间，术后24 h内补救镇痛情况和恶心呕吐、皮肤瘙痒、呼吸抑制等不良反应发生情况。结果 与R组比较，A组术中低血压发生率明显降低(P<0.05),术后30、60 min无痛发生率明显升高(P<0.05),...     

异丙酚联合瑞芬太尼或芬太尼全静脉麻醉在宫颈癌根治术中的临床观察

目的 比较异丙酚-瑞芬太尼和异丙酚-芬太尼全静脉麻醉用于宫颈癌根治术对血流动力学和苏醒的影响。方法 60例ASA Ⅰ-Ⅱ级行宫颈癌根治术的患者随机分为两组，PR组采用异丙酚和瑞芬太尼全静脉麻醉，PF组采用异丙酚和芬太尼全静脉麻醉。两组均记录术前、麻醉诱导后、气管插管时、气管插管后5min及围术期的血压、心率值。手术结束后记录睁眼时间、拔管时间、拔管后即刻、30min疼痛视觉模拟评分（VAS）和不良反应。结果 PR组插管期心血管不良反应显著低于PF组（P〈0．05），PR组术后睁眼时间和拔管时间明显短于PF组（P〈0．05）。两组患者均未出现术中知晓，术中恶心呕吐发生率差异无统计学意义。结论 与异丙酚-芬太尼全静脉麻醉相比，异丙酚-瑞芬太尼全静脉麻醉苏醒更加迅速，能更好地控制气管插管时的应激反应，而且并不增加不良反应发生率。瑞芬太尼半衰期短，需提前实施术后镇痛。     

异丙酚、地氟醚或七氟醚复合瑞芬太尼麻醉对脑功能区手术患者术中唤醒试验的影响

目的 探讨异丙酚、地氟醚或七氟醚复合瑞芬太尼麻醉对脑功能区手术患者术中唤醒试验的影响.方法 择期拟行脑功能区肿瘤切除术患者60例,ASA Ⅰ或Ⅱ级,年龄18～60岁,随机分为3组:异丙酚组(P组)、地氟醚组(D组)及七氟醚组(S组),每组20例.静脉注射依托咪酯0.3mg/kg、芬太尼3 μg/kg、维库溴铵0.1 mg/kg行麻醉诱导,采用1%丁卡因喉头及气管粘膜表面麻醉后行气管插管.P组、D组和S组分别靶控输注异丙酚,血浆靶浓度2.0μg/ml,持续吸入地氟醚、七氟醚1.5 MAC维持麻醉.各组均靶控输注瑞芬太尼,血浆靶浓度2.5 ng/ml,唤醒试验前血浆靶浓度降为0.5 ng/ml,静脉注射曲马多100mg,停用麻醉药,行唤醒试验.记录唤醒时间,观察唤醒试验时躁动及寒颤的发生情况.结果 各组患者唤醒时间差异无统计学意义(P>0.05),P组寒颤发生率较D组和S组高(P<0.05).结论 采用异丙酚、地氟醚或七氟醚复合瑞芬太尼麻醉,脑功能区手术患者术中唤醒时间无差别,地氟醚或七氟醚复合瑞芬太尼麻醉时有关并发症发生率低,更适用于术中唤醒试验.     

老年人工髋关节置换术中的麻醉方案选择及应用

目的探讨老年人工髋关节置换术中的麻醉方案选择及应用。方法随机选取2019年1月至2019年8月本院老年人工髋关节置换术患者100例,随机分为异丙酚复合瑞芬太尼静脉麻醉组(瑞芬太尼组,n=50)和异丙酚复合芬太尼静脉麻醉组(芬太尼组,n=50)2组,统计分析两组患者MMSE评分、Ramsay评分、VAS评分、麻醉唤醒时间、唤醒质量、术后准确定向时间的差异。结果组内比较,两组患者术后15、30、60分钟的MMSE评分均逐渐升高(P0.05),术后15分钟、30分钟的MMSE评分均显著低于麻醉诱导前、术后60分钟(P0.05),术后15分钟的MMSE评分均显著低于术后30分钟(P0.05),但麻醉诱导前、术后60分钟的MMSE评分之间的差异均不显著(P0.05);组间比较,麻醉诱导前两组患者的MMSE评分之间的差异不显著(P0.05),术后15、30、60分钟瑞芬太尼组患者的MMSE评分均显著高于芬太尼组(P0.05)。瑞芬太尼组和芬太尼组患者唤醒后Ramsay评分逐渐降低(P0.05),VAS评分无显著变化(P0.05),组间对比:瑞芬太尼组唤醒后5分钟、唤醒后10分钟Ramsay评分低于芬太尼组(P0.05),唤醒后20分钟后Ramsay评分与芬太尼组无显著差异(P0.05)。两组唤醒后5分钟、唤醒后10分钟、唤醒后20分钟VAS评分比较无统计学差异(P0.05)。瑞芬太尼组患者麻醉唤醒时间、术后准确定向时间均显著短于芬太尼组(P0.05),唤醒质量显著高于芬太尼组(P0.05)。结论老年人工髋关节置换术中异丙酚复合瑞芬太尼静脉麻醉较异丙酚复合芬太尼静脉麻醉效果好。     

异丙酚-瑞芬太尼和异氟烷-芬太尼麻醉下肝切除术患者肝缺血再灌注损伤的比较

目的 通过比较异丙酚-瑞芬太尼与异氟烷-芬太尼麻醉下肝切除术患者肝脏缺血再灌注损伤的程度,探讨肝切除术适宜的麻醉方法 .方法 择期行肝部分切除术患者30例,年龄41～64岁,体重58～86 kg,ASA Ⅰ或Ⅱ级,肝功能Child A级,随机分为异丙酚-瑞芬太尼组(PR组)和异氟烷-芬太尼组(IF组),每组15例.静脉注射咪达唑仑、芬太尼、依托咪酯和维库溴铵行麻醉诱导,气管插管后行机械通气.麻醉维持:PR组靶控输注异丙酚(血浆靶浓度3.5 μg/ml)和瑞芬太尼(血浆靶浓度4.2ng/ml);IF组吸入1.5%～2.5%异氟烷,问断静脉注射芬太尼2 μg/kg;2组均间断静脉注射维库溴铵维持肌松.于肝门阻断前(T1)、肝门开放后即刻(T2)、30 min(T3)、60 min(T4)和术后1 d(T5)时取右颈内静脉血样,测定血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、γ-谷氨酰转肽酶(γ-GGT)、乳酸脱氢酶(LDH)、总胆红素(TBIL)、总超氧化物歧化酶(T-SOD)和丙二醛(MDA)的水平.结果 与IF组比较,PR组T5时ALT活性降低,L3、T4时γ-GGT活性降低,T5时T-SOD活性升高,T4、T5时MDA浓度降低(P<0.05).结论 与异氟烷-芬太尼麻醉相比,异丙酚-瑞芬太尼麻醉可减轻患者肝脏缺血再灌注损伤的程度,更适用于肝切除术.     

CYP3A4酶与妇科手术后芬太尼镇痛效应的关系

目的 评价CYP3A4酶与妇科手术后芬太尼镇痛效应的关系.方法 择期行妇科子宫肌瘤剔除术或子宫全切术的病人159例,年龄30～50岁,ASA分级Ⅰ或Ⅱ级.麻醉诱导:静脉注射咪达唑仑、瑞芬太尼、异丙酚和琥珀胆碱,气管插管后行机械通气.麻醉维持:静脉输注异丙酚和瑞芬太尼,间断静脉注射阿曲库铵.静脉注射咪达唑仑后1 h时,取静脉血样5 ml,采用液相色谱-质谱法测定血浆1-羟基咪达唑仑和咪达唑仑的浓度,以1-羟基咪达唑仑浓度与咪达唑仑浓度的比值反映CYP3A4酶的效应强度.术毕清醒后行VAS评分,VAS评分＞4分时,静脉注射芬太尼10μg/5 min,直至VAS评分≤4分后采用芬太尼行病人静脉自控镇痛,维持VAS评分≤4分.记录术后24 h内和24～48 h时的镇痛泵有效按压次数和48 h内芬太尼消耗量.CYP3A4酶的效应强度与术后镇痛泵有效按压次数和芬太尼消耗量行Pearson相关性分析.结果 CYP3A4酶的效应强度与术后24 h内、24～48 h时有效按压次数及48 h芬太尼的总消耗量之间无相关性,相关系数分别为0.16、0.13、0.11(P＞0.05).结论 CYP3A4酶不是芬太尼代谢的主要酶.     

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.