瑞芬太尼、丙泊酚复合七氟醚在小儿腹股沟斜疝腹腔镜手术中的麻醉效果

目的探讨瑞芬太尼与丙泊酚分别复合七氟醚在小儿腹股沟斜疝腹腔镜手术中的麻醉效果。 方法选取2020年6月至2021年6月在宣城市中心医院进行腹腔镜腹股沟斜疝择期手术的患儿60例作为研究对象。将所有患儿按随机数字表法分为2组,瑞芬太尼组采用瑞芬太尼联合七氟醚麻醉（30例）;丙泊酚组患者采用丙泊酚联合七氟醚麻醉（30例）。记录2组患儿术毕拔管时间、苏醒时间、定向恢复时间,麻醉前（T₀）、诱导后（T₁）、气腹5 min（T₂）、拔管后（T₃）各时间段内的平均动脉压（MAP）、心率、血氧饱和度（SpO₂）等应激指标,术后儿童麻醉苏醒期躁动评分量表（PAED）和儿童疼痛行为量表（FLACC）,以及患儿术后不良反应发生情况。 结果瑞芬太尼组患儿拔管时间、苏醒时间、定向恢复时间均小于丙泊酚组（P<0.05）;与T₀相比,2组患儿T₂、T₃的MAP、心率、SpO₂均逐渐降低（P<0.05）。在相同阶段对比中,瑞芬太尼组T₁、T₂、T₃的MAP、心率波动均小于丙泊酚组（P<0.05）,SpO₂高于丙泊酚组（P<0.05）;瑞芬太尼组术后PAED评分低于丙泊酚组（P<0.05）;苏醒6 h（t₂）、苏醒12 h（t₃）时刻较苏醒时（t₀）时刻2组疼痛评分均明显降低（P<0.05）;且瑞芬太尼组t₀~t₃的FLACC评分均低于丙泊酚组（P<0.05）;瑞芬太尼组总不良反应低于丙泊酚组（P<0.05）。 结论七氟醚联合瑞芬太尼在小儿股沟斜疝腹腔镜术中麻醉效果和血流动力学优于丙泊酚组,缩短患儿术后苏醒时间,有效缓解患儿术后疼痛和躁动程度,减轻对患儿呼吸抑制等不良反应的影响。     

七氟醚与丙泊酚用于小儿烧伤手术麻醉维持的比较

目的比较七氟醚与丙泊酚用于小儿烧伤手术麻醉维持的效果。方法择期手术烧伤患儿60例,随机分为丙泊酚组(P组)和七氟醚组(S组),每组30例。气管插管后P组泵注丙泊酚3~8 mg.kg-1.h-1维持麻醉,S组吸入1%~4%七氟醚维持麻醉;需要时均间断静注芬太尼和阿曲库铵。术毕前5 min停用丙泊酚和七氟醚。记录术中血流动力学指标以及术毕患儿自主呼吸恢复时间、苏醒时间、拔管时间、苏醒时躁动情况。结果气管拔管后P组SpO2明显降低,且低于S组(P<0.05)。S组患儿自主呼吸恢复时间、拔管时间和苏醒时间均明显短于P组(P<0.01)。结论七氟醚用于小儿烧伤手术麻醉维持循环稳定,术毕自主呼吸恢复快、苏醒迅速,拔管及时,躁动发生率低,麻醉效果优于丙泊酚。     

七氟醚对心肺转流冠状动脉旁路移植术的心肺保护作用

目的 比较七氟醚与丙泊酚对心肺转流(CPB)冠状动脉旁路移植术(CAEG)患者心肌与肺功能的保护作用.方法 择期CPB下行CABG患者52例,ASAⅡ或Ⅲ级,心功能Ⅱ或Ⅲ级,随机均分为七氟醚组(S组)与丙泊酚组(P组).夹闭主动脉后,S组通过膜肺吹入0.5%～3%七氟醚,P组靶控输注丙泊酚2～3μg/kg.予术前、术后2、4、8 h行血气分析,计算肺泡-动脉氧分压差[D(A-a)O<,2>]、呼吸指数(RI)及氧合指数(OI);予术前、术后6、12、24、48 h检测肌酸激酶同工酶(CK-MB)与肌钙蛋白I(cTnI)水平;记录房颤(Af)发生率、心肌缺血率、射血分数(EF)、自动复跳率及呼吸支持时间.结果 术后各时点S组患者D(A-a)O<,2>与RI明显低于P组(P<0.05);而OI明显高于P组(P<0.05).S组术后CK-MB与cTnl明显低于P组(P<0.01).Af发生率与心肌缺血率明显低于P组,呼吸支持时间明显短于P组(P<0.05),EF值和自动复跳率明显高于P组(P<0.05).结论 CPB下CABG中通过膜肺给予七氟醚对患者心肌与肺功能有一定的保护作用.     

小剂量舒芬太尼复合丙泊酚在宫腔镜检查术的临床应用

目的探讨小剂量舒芬太尼复合丙泊酚在宫腔镜检查术中的临床应用效果。方法选择拟行宫腔镜检查术的女性患者80例,随机均分为四组。P组仅给予丙泊酚2mg/kg,另三组分别复合舒芬太尼0.1μg/kg(S1组)、0.15μg/kg(S2组)和0.2μg/kg(S3组)。观察并记录麻醉前、麻醉后3min、扩宫颈时、术毕时患者MAP、HR、丙泊酚用量、术中SpO2<85%例数和术后不良反应。记录清醒即刻(T0)、术后15min(T1)、30min(T2)、1h(T3)、2h(T4)及6h(T5)下腹疼痛情况(Prince-Henry评分)。结果与S3组比较,麻醉后3min、扩宫颈时和术毕时S1、S2和P组MAP明显升高(P<0.05);S1、S2组患者苏醒时间明显缩短(P<0.05),S1、S2和P组术中SpO2<85%患者例数明显减少(P<0.05)。与P组比较,S1、S2组苏醒时间明显缩短、S1、S2和S3组丙泊酚用量明显减少(P<0.05)。与S1组比较,T0～T3时S2、S3组Prince-Henry评分明显降低,P组Prince-Henry评分明显升高(P<0.05)。与P组比较,T0～T5时S2、S3组Prince-Henry评分明显降低(P<0.05)。S1、S2、S3组术后烦躁发生率明显低于P组(P<0.05)。结论小剂量舒芬太尼复合丙泊酚可以提高宫腔镜检查术患者术后镇痛效果,减少术中丙泊酚用量。0.15μg/kg舒芬太尼复合丙泊酚2mg/kg在宫腔镜检查术应用安全性更高。     

七氟醚或丙泊酚维持麻醉对妇科腹腔镜手术患者术后疼痛的影响

目的通过观察不同麻醉维持方式下妇科腹腔镜手术患者术后疼痛的情况,比较七氟醚或丙泊酚维持麻醉对患者术后疼痛的影响。方法选择择期行妇科腹腔镜手术女性患者60例,年龄18~65岁,BMI 18~30 kg/m^2,ASAⅠ或Ⅱ级。采用随机数字表法随机分为七氟醚组(S组)和丙泊酚组(P组),每组30例。两组以相同方案麻醉诱导后,S组吸入1.5%~4%七氟醚维持麻醉,P组靶控输注丙泊酚,血浆靶浓度3~6μg/ml。术中维持BIS 40~60。记录术后30 min、1、3、6、24和48 h时患者活动时VAS评分;记录术前1 d、术后3、24和48 h机械性痛阈值;记录术后24 h PCIA按压次数、芬太尼消耗量;记录追加哌替啶的例数和恶心呕吐、寒颤、瘙痒、躁动等不良反应发生情况。结果与术后30 min比较,术后3、6 h两组活动时VAS评分明显升高(P<0.05),术后48 h明显降低(P<0.05)。术后30 min、1和3 h P组活动时VAS评分明显低于S组(P<0.05)。与术前1 d比较,术后3、24和48 h S组机械性痛阈明显降低(P<0.05),术后3 h P组机械性痛阈明显降低(P<0.05)。术后3 h P组机械性痛阈值明显高于S组(P<0.05)。两组PCIA按压次数、芬太尼消耗量、追加哌替啶情况和不良反应发生情况等差异无统计学意义。结论与七氟醚吸入维持麻醉比较,妇科腹腔镜手术中使用丙泊酚静脉维持麻醉可以提高患者术后的机械性痛阈,减轻患者在术后3 h内的疼痛。     

七氟醚对二氧化碳气腹血浆心钠素及内皮素的影响

目的观察七氟醚对腹腔镜手术下血浆心钠素（ANP）及内皮素（ET）的影响。方法择期腹腔镜胆囊切除手术患者40例,随机双盲均分为两组:研究组（S组）,术中吸入七氟醚维持麻醉;对照组（P组）,术中持续靶控输注丙泊酚。记录麻醉前（T₀）、插管前（T₁）、插管后（T₂）、气腹即刻（T₃）、气腹15min（T₄）、气腹结束（T₅）、手术结束（T₆）时的MAP、HR。检测T₀、T₃～T₅时两组血浆ANP和ET的含量。结果 T₃时P组的MAP明显高于T₁、T₂、T₅时（P<0.05）;T₆时S组HR明显快于T₃时（P<0.05）;P组T₃～T₅时ET、T₅时ANP明显高于T₀时和S组（P<0.05）。结论七氟醚能够减轻气腹状态下ET分泌,稳定ANP,抑制应激反应,稳定血流动力学。     

七氟醚-瑞芬太尼麻醉用于腹腔镜胆囊切除术患者的效果

目的 评价七氟醚-瑞芬太尼麻醉对腹腔镜胆囊切除术(LC)患者血流动力学、苏醒质量,以及认知功能的影响。方法 择期行LC的胆囊结石患者84例,性别不限,年龄33～61岁,BMI 19～24 kg/m²。ASAⅠ～Ⅱ级。采用随机数字表法分为七氟醚-瑞芬太尼组(S组)和丙泊酚-瑞芬太尼组(P组),每组42例。记录2组患者麻醉前(T₀)、麻醉后10 min(T₁)、手术进行时(T₂)、术毕时(T₃)的SpO₂、HR、 MAP血流动力学指标和患者的自主呼吸恢复时间、指令动作恢复时间、言语顺利应答时间、定向力恢复时间苏醒等质量指标。评价术后2 h、6 h、12 h、24 h的视觉模拟评分法(VAS)评分。统计呼吸抑制等不良反应发生率。结果 T₁、T₂、T₃时S组患者的SpO₂、HR、 MAP血流动力学指标稳定性均优于P组;术后自主呼吸恢复时间、指令动作恢复时间、言语顺利应答时间、拔...     

七氟醚吸入对危重新生儿术中肺表面活性蛋白A和B的影响

目的观察吸入七氟醚对危重新生儿术中肺表面活性蛋白A(SPA)和肺表面活性蛋白B(SPB)的影响。方法选择行腹部手术危重新生儿40例,男29例,女11例,出生12～26 d,体重3.0～4.1 kg, ASAⅢ或Ⅳ级,随机分为两组:七氟醚组(S组)和对照组(C组),每组20例。S组于麻醉诱导气管内插管成功后,吸入2.5%七氟醚30 min;C组不予吸入麻醉药物。两组均在超声引导下行颈内静脉和桡动脉穿刺置管术,容量控制机械通气,持续泵入咪达唑仑2μg·kg~(-1)·min~(-1)、顺式阿曲库铵2～3μg·kg~(-1)·min~(-1)、芬太尼2～4μg·kg~(-1)·h~(-1)维持麻醉。记录机械通气开始时(T_0)、机械通气开始后30 min (T_1)、手术结束即刻(T_2)时PaCO_2和PaO_2,计算呼吸指数(RI)、氧合指数(OI),采用ELISA法检测动脉血血清SPA、SPB和IL-8浓度,记录肺炎、肺气漏、ARDS、颅内出血、DIC、电解质紊乱、切口感染等术后并发症发生情况。结果与T_0时比较,T_1—T_2时两组OI和血清SPA、SPB浓度明显降低(P0.05),RI和血清IL-8浓度明显升高(P0.05)。T_0时两组RI、OI、血清SPA、SPB和IL-8浓度差异无统计学意义。T_1—T_2时S组RI和血清IL-8浓度明显低于C组(P0.05),OI和血清SPA、SPB浓度明显高于C组(P0.05)。S组术后肺炎发生率明显低于C组(P0.05)。结论吸入七氟醚能减轻危重新生儿术中炎性介质的释放,改善肺氧合功能,减少术后并发症的发生。     

七氟醚后处理对心脏瓣膜置换术患者心肺转流后血管紧张素转换酶的影响

目的评价七氟醚后处理对心脏瓣膜置换术患者心肺转流(CPB)后血管紧张素转换酶(ACE)的影响。方法择期行CPB下心脏瓣膜手术患者30例,年龄30~70岁,体重45~80kg,男23例,女7例,ASAⅡ或Ⅲ级,心功能Ⅱ或Ⅲ级,随机均分为七氟醚后处理组(S组)和对照组(C组)。S组于主动脉开放前2min向膜式氧合器中预充2%七氟醚,主动脉开放后恢复机械通气继续吸入2%七氟醚15min,对照组不给予任何吸入性麻醉药物。分别于麻醉诱导前(T1)、CPB结束后30min(T2)、术后6h(T3)、术后24h(T4)时采集颈内静脉血样5ml,采用酶偶联法测定血清血管紧张素转换酶(SACE)。并于上述四个时点采集桡动脉血样行血气分析,记录PaO2、SaO2、PaCO2以计算RI、OI和PaO2/PAO2。记录术后患者机械通气时间、肺部啰音发生率、拔管后24h内呼吸困难以及再次气管插管的发生情况。结果T2、T3时S组患者的OI、PaO2/PAO2明显高于C组(P0.05),RI、SACE水平明显低于C组(P0.05),机械通气时间明显短于C组(P0.05),肺部啰音发生率明显低于C组(P0.05)。结论心脏瓣膜置换术中七氟醚后处理可以降低SACE水平,减轻患者CPB后肺功能损伤,对保护肺功能有利。     

全麻联合罗哌卡因硬膜外输注对胸乳入路甲状腺切除患者皮质醇的影响

目的观察全麻联合罗哌卡因硬膜外输注对胸乳入路甲状腺切除患者血浆皮质醇的影响。 方法40例甲状腺切除患者随机分2组,每组20例:A组患者全凭静脉麻醉;B组患者全麻之前行T_4-5硬膜外置管(0.1%罗哌卡因输注2 ml/h)。记录麻醉前(T₀)、插管后5 min(T₁)、切皮后60 min(T₂)、拔管后5 min(T₃) MAP、HR、Cor变化;术后6 h(T₄)、12 h(T₅)、以及24 h(T₆)视觉模拟评分(VAS),术中丙泊酚、瑞芬太尼用量,拔管时间及镇痛泵按压(PCA)次数。 结果与T₀比较,两组患者T₁时MAP、HR降低,T₂、T₃时HR降低,Cor增高,B组患者MAP降低(P<0.05);与A组比较,B组患者T₁时MAP、HR降低,T₂、T₃时Cor降低(P<0.05);A组患者T₅时VAS评分比T₄增高(P<0.05);两组患者T₆时VAS评分较T₅降低(P<0.05)。与A组比较,B组患者T₅时VAS评分降低(P<0.05),术中丙泊酚、瑞芬太尼用量,拔管时间以及镇痛泵按压次数降低(P<0.05)。 结论全麻联合0.1%罗哌卡因硬膜外输注对胸乳入路甲状腺切除患者可良好控制术中应激和术后疼痛,降低麻醉药物需求。     

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.     

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.     

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.