七氟醚不同吸入方式对瓣膜置换术患者血清肌钙蛋白-T及炎性细胞因子的影响

目的观察七氟醚不同吸入方式对心肺转流(CPB)下心脏瓣膜置换术中血清肌钙蛋白T(cTnT)和炎性细胞因子IL-6、IL-8浓度的影响,探讨不同七氟醚处理方法的心肌保护作用及其机制。方法 52例拟行全身麻醉下CPB心脏瓣膜置换术的患者,随机均分为:七氟醚预处理组(S1组)、七氟醚后处理组(S2组)和七氟醚预处理联合后处理组(S3组)和对照组(C组)。S1组:麻醉诱导后连续吸入1%七氟醚至主动脉阻断;S2组:主动脉、腔静脉开放后连续吸入1%七氟醚至手术结束;S3组:麻醉诱导后连续吸入1%七氟醚至主动脉阻断时停止,主动脉、腔静脉开放后再连续吸入1%七氟醚至手术结束;C组在整个麻醉手术期间不吸入七氟醚。于麻醉诱导后即刻(T0)、主动脉开放后2h(T1)、6h(T2)、12h(T3)和24h(T4)分别采集桡动脉血3ml,测定cTnT、IL-6和IL-8浓度。结果与T0时比较,T1~T3时S1组、S2组和S3组血清cTnT、IL-6和IL-8浓度明显升高(P0.05)。与C组比较,T1~T3时S1组、S2组和S3组血清cTnT、IL-6和IL-8浓度明显降低(P0.05);而T4时S1组、S3组血清cTnT浓度和S1组、S2组和S3组血清IL-6、IL-8浓度明显降低(P0.05)。结论七氟醚预处理、七氟醚后处理和七氟醚预处理联合后处理三种方式均可有效显减轻瓣膜置换术中心肌缺血-再灌注损伤,心肌保护作用相近,机制可能与抑制全身炎症反应有关。     

七氟醚后处理对换瓣术患者炎性因子及心肌超微结构的影响

目的研究七氟醚后处理对心脏瓣膜置换术患者全身炎性因子和心肌超微结构的影响。方法经心肺转流(CPB)瓣膜置换术患者随机分为七氟醚后处理组(S组)与对照组(C组),每组15例。S组于主动脉开放即刻经CPB输氧装置以2%七氟醚后处理15min,C组不做此处理采取全凭静脉麻醉。测定手术开始时(T1)、主动脉开放后0.5h(T2)、3h(T3)、24h(T4)时血浆IL-6、IL-10浓度,电镜下观察心肌超微结构的变化。结果与C组比较,S组T2～T4时血浆IL-6和IL-10的浓度降低(P<0.05);与T1时比较,T2、T3时两组血浆IL-6与IL-10浓度升高(P<0.05)。结论七氟醚后处理可以降低瓣膜置换术患者CPB后炎性因子的释放,减轻心肌超微结构的损伤,有利于心功能的恢复。     

七氟醚预先给药对心脏瓣膜置换术患者炎性反应的影响

目的 评价七氟醚预先给药对体外循环(CPB)下心脏瓣膜置换术患者炎性反应的影响,探讨其心肌保护作用的机制.方法 择期拟行心脏瓣膜置换术的风湿性心脏病患者20例,采用随机数字表法,将患者随机分为七氟醚组(S组)和对照组(C组),每组10例.S组于主动脉阻断前吸入七氟醚,呼气末浓度1.0％,维持30 min.于切皮前、主动脉阻断即刻、主动脉开放即刻、主动脉开放后30 min、术后2、6、12、24 h(T1～8)时抽取中心静脉血样,测定血浆肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、IL-8、细胞粘附分子-1(ICAM-1)及肌钙蛋白I(cTnI)的浓度与肌酸激酶同工酶(CK-MB)活性;并记录主动脉开放后心血管活性药物的使用情况.结果 与C组比较,S组T3～8时血浆TNF-α、IL～6、IL8浓度降低,T4～8时血浆ICAM-1及cTnI浓度降低,T8时CK-MB活性降低,心血管活性药物使用率降低(P＜0.05).结论 七氟醚预先给药可抑制炎性反应,对CPB下心脏瓣膜置换术患者心肌产生一定的保护作用.     

七氟醚缺血后处理对心脏瓣膜置换术中血清肌钙蛋白T和心肌细胞内活性氧簇的影响

目的观察七氟醚缺血后处理对风湿性心脏病(RHD)患者单瓣膜置换术中血清心肌肌钙蛋白T(cTnT)和心肌细胞内活性氧簇(ROS)的影响,探讨其对缺血-再灌注心肌的保护作用。方法择期行心脏单瓣膜置换术的RHD患者24例,随机均分为两组,七氟醚缺血后处理组(S组)行1MAC七氟醚缺血后处理5min,对照组(C组)不予七氟醚缺血后处理。采集动脉血检测cTnT,采用二氯荧光素法测定心肌细胞内ROS水平。结果与术前比较,主动脉开放后1～4h时两组血清cTnT浓度均明显升高(P<0.05),但S组明显低于C组(P<0.05)。与主动脉阻断前比较,主动脉开放后1h两组心肌细胞内ROS水平均显著增加(P<0.05),但S组明显低于C组(P<0.05)。结论七氟醚缺血后处理心肌保护作用可能与抑制缺血-再灌注心肌细胞内ROS过度生成有关。     

七氟醚后处理对瓣膜置换术中血清肌钙蛋白T及IL-6、IL-8浓度的影响

目的 观察七氟醚后处理对瓣膜置换术中血清心肌损伤标志物肌钙蛋白T(cTnT)及白细胞介素( IL)-6、IL-8浓度的影响,探讨其心肌保护作用.方法 24例拟行单瓣膜置换术的风湿性心脏病患者,随机均分为七氟醚组(S组)和对照组(C组).两组采用相同麻醉及体外循环方法.S组在主动脉开放后即刻吸人5％七氟醚,呼气末浓度达1 MAC后调整吸入浓度并维持1 MAC 10min,C组不吸入七氟醚.麻醉后即刻(T1)和主动脉开放后1 h(T2)、2 h(T3)、4 h(T4)经桡动脉采血3ml,分别用电化学发光法和放射免疫法测定血清cTnT和IL-6、IL-8浓度.结果 两组T2～T4时血清cTnT、IL-6、IL-8浓度均明显高于T1时,但S组明显低于C组(P＜0.05).结论 七氟醚后处理能明显减轻瓣膜置换术中心肌缺血-再灌注损伤,其机制可能与抑制全身炎症反应有关.     

异氟醚预处理对心脏瓣膜置换术中患者中性粒细胞NF-κB活性的影响

目的 探讨异氟醚预处理对心脏瓣膜置换术中患者中性粒细胞NF-κB活性的影响.方法 择期体外循环(CPB)下二尖瓣和/或主动脉瓣置换术患者20例,ASAⅡ或Ⅲ级,年龄20～60岁,随机分成2组对照组(C组)和异氟醚预处理组(Ⅰ组),每组10例.两组麻醉诱导均采用静脉注射咪唑安定0.08～0.12 mg·kg-1、芬太尼5～10μg·kg-1、维库溴铵0.1 mg·kg-1;气管插管后机械通气.麻醉维持C组间断静脉注射芬太尼、咪唑安定及维库溴铵,Ⅰ组吸入异氟醚2 MAC及间断静脉注射芬太尼、咪唑安定、维库溴铵.CPB前维持收缩压90～120 mm Hg、舒张压50～80 mm Hg及心率60～90次·min-1;CPB开始时Ⅰ组停吸异氟醚.于气管插管后即刻(T0)、主动脉开放后30 min(T1)、1 h(T2)、2 h(T3)采桡动脉血15ml,并分离提取中性粒细胞,用凝胶电泳迁移率改变分析法测定中性粒细胞NF-κB活性,记录心脏自动复跳情况、多巴胺及硝普纳用量.结果 与C组比较,Ⅰ组T0时NF-κB活性差异无统计学意义,而其他时点NF-κB活性降低,心脏自动复跳率升高,多巴胺用量降低(P＜0.05),硝普钠用量差异无统计学意义(P＞0.05);每组多巴胺用量与中性粒细胞NF-κB活性的最高值呈正相关[C组r=0.962,Ⅰ组r=0.908(P＜0.01)].结论 异氟醚预处理通过降低中性粒细胞NF-κB活性,对CPB下心脏瓣膜置换术患者心肌产生一定的保护作用.     

七氟醚后处理对体外循环下冠状动脉旁路移植术病人心肌缺血再灌注损伤的影响

目的 探讨七氟醚后处理对体外循环(CPB)下冠状动脉旁路移植术病人心肌缺血再灌注损伤的影响.方法 择期行冠状动脉旁路移植术病人40例,性别不限,年龄55～64岁,BMI＜30 kg/m2,NYHA心功能分级Ⅰ～Ⅲ级,随机分为2组(n=20):对照组(C组)和七氟醚后处理组(S组).S组于主动脉开放即刻通过体外循环机吸入2%七氟醚,持续15 min,C组不给予任何处理.分别于麻醉诱导后、CPB转流前、停机后10 min、术毕、术后6和24 h时,记录MAP、HR、CVP、平均肺动脉压、肺动脉楔压、CO和S(v)O2,计算CI、SVI、体循环血管阻力指数和肺循环血管阻力指数.分别于主动脉阻断前、复灌6 h和术后24 h时,中心静脉取血样,测定血浆肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)和乳酸脱氢酶(LDH)的活性以及肌钙蛋白I(TnI)浓度.分别于主动脉阻断前和CPB停机时,取右心耳心肌组织,观察心肌细胞超微结构,并对心肌细胞损伤程度进行评分.结果 两组间各时点血液动力学和心功能指标比较差异无统计学意义(P＞0.05).与C组比较,S组复灌6 h时血浆CK-MB和LDH活性降低,术后24 h时血浆CK活性和TnI浓度降低,CPB停机后心肌细胞损伤程度评分降低(P＜0.05).结论 七氟醚后处理可减轻CPB下冠状动脉旁路移植术病人心肌缺血再灌注损伤.     

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。     

异氟醚预处理对心脏瓣膜置换术病人血清一氧化氮与肌钙蛋白Ⅰ的影响

目的探讨异氟醚预处理对心肌缺血-再灌注损伤的保护效应及机制。方法择期行心脏瓣膜置换术的风湿性心脏瓣膜病病人32例,随机分为异氟醚组和对照组,每组16例。异氟醚组以1.5%~2%异氟醚吸入复合芬太尼维持麻醉,心肺转流(CPB)开始前洗脱10min,CPB后以芬太尼维持麻醉;对照组以芬太尼维持麻醉。分别于麻醉前(T0)、CPB前(T1)、CPB30min(T2)、术后8h(T3)、24h(T4)抽取中心静脉血测定一氧化氮(NO)、NO合酶(NOS)与心肌肌钙蛋白I(cTnI)浓度。结果两组病人T0时NO、NOS与cTnI浓度差异无显著意义;异氟醚组T1、T2时NO、NOS浓度明显高于对照组(P<0·05),T3、T4时cTnI浓度明显低于对照组(P<0·05)。结论异氟醚具有心肌预适应作用,其机制可能与增加NO释放有关。     

丙泊酚与七氟醚对体外循环期间肠道屏障功能影响的比较

目的：比较心脏手术CPB期间丙泊酚和七氟醚对肠道屏障功能的影响。方法：选择需CPB的心脏手术90例,随机分为非CPB对照组C、丙泊酚组P组和七氟醚组S组n=30。三组病例麻醉诱导均采用咪唑安定、芬太尼、依托咪酯、罗库澳铵快速气管插管。麻醉维持C与P组用丙泊酚靶控输注,辅助芬太尼和罗库溴铵。S组用七氟醚吸入,辅助芬太尼和罗库溴铵。P和S组病人分别在麻醉前T1、CPB前T2、CPB30分钟时T2、CPB停机后30分钟T4采取中心静脉血、C组在麻醉前T1、手术开始后15minT2、手术开始后40minT3、手术结束时T4采集中心静脉血检测血浆内毒素浓度。结果：麻醉前三组血浆内毒素浓度均在正常范围,无统计学差异在T3、T4时P组和S组血浆内毒素浓度明显高于C组（P〈0.01）、S组高于P组（P〈0.01）,T2时S组高于P组和C组（P〈0.05）.结论：CPB期间异丙酚对肠道屏障功能的保护作用优于七氟醚.     

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.