二尖瓣成形术早期血流动力学变化

报告39例二尖瓣成形术手术前后早期血流动力学指标变化情况。麻醉诱导前及术后早期测量右房压(RAP)、平均肺动脉压(MPAP)、肺毛细血管嵌压(PCWP)、平均动脉压(MAP)、心输出量(CO)，并计算出心脏指数(CI)、肺血管阻力指敷(PVRI)、外周血管阻力指数(SVRI)、左室作功指数(LVWI)、右室作功指数(RVWI)值。结果：术后早期MPAP、PCWP明显下降，说明二尖瓣成形术基本纠正了二尖瓣狭窄点(和)关闭不全的病变，使房压明显下降。结论：二尖瓣成形术早期血流动力学指标有明显改善，但长期效果有待严密随访。     

非体外循环冠状动脉旁路移植术的血流动力学研究

目的：分析非体外循环冠状动脉旁路移植术中血流动力学的变化。方法：2000年6月至2001年1月，连续32例病人接受非体外循环冠状动脉旁路移植术，术中、术后对各吻合血管的血流动力学指标进行持续监测。全组完成前降支吻合32例、右冠状动脉26例、回旋支28例、对角支8例。结果：本组死亡例。行前降支冠状动脉吻合时血流动力学指标无明显变化。右冠状动脉吻合时影响右心功能。回旋支及对角支冠状动脉吻合时对血流动力学有明显的影响，导致平均肺动脉压（MPAP）、肺毛细血管楔压（PAWP）、中心静脉压（CVP）明显升高，每搏指数（SVI）及左室每搏功指数（LVSWI）有明显下降；心排指数（CI）有一定的下降趋势。行主动脉近心端吻合时尽管已无心脏搬动，但MPAP、SVRI及肺循环阻力指数（PVRI）仍较诱导后有明显升高，CI有明显下降。术毕及术的2、6、16h各血流动力学指标趋于正常，CI有明显改善。结论：非体外循环冠状动脉旁路移植行前降支及右冠状动脉吻合时对血流动力学影响较小，回旋支及对角支冠状动脉吻合时对血流动力学有明显的影响，术毕及术后2、6、16h各血流动力学指标趋于正常，心脏功能有明显改善。     

肝硬化病人肝移植术中右心室容量的变化

目的 采用右心室舒张末容量指数监测,观察评估肝硬化病人肝移植术中右心室容量的变化.方法 拟行改良背驮肝移植手术病人26例,ASA Ⅲ或Ⅳ级,肝功能Child分级B级22例、C级4例,心功能Ⅰ或Ⅱ级.分别在切皮前(T0)、无肝期前10 min(T1)、无肝期30 min(T2)、新肝期15 min(T3)、新肝期30 min(T4)和新肝期90 min(T5)记录右心室舒张末容量指数(RVEDVI)、心指数(CI)、右室射血分数(RVEF)和每搏量指数(SVI)等参数.结果 与T0比较,无肝期RVEDVI、RVEF、CI和SVI均下降;进入新肝期后RVEDVI、RVEF、CI和SVI在T3时下降,T4时回到T0水平.与T2比较,T3的RVEDVI、RVEF、CI和SVI变化不明显,T4的RVEDVI、RVEF、CI和SVI增加.与T3比较,T4和T5的RVEDVI、RVEF、SVI和CI明显增加.结论 RVEDVI能较好评估肝硬化肝移植病人的右心室的容量变化.     

双心房输注对二尖瓣置换术患者体外循环后肺动脉压的影响

目的 评价双心房输注对二尖瓣置换术患者体外循环后肺动脉压(PAP)的影响.方法 择期行二尖瓣置换术合并肺动脉高压[平均肺动脉压(MPAP)＞50 mm Hg]的患者20例,年龄22～53岁,体重34～57kg,心功能分级Ⅱ或Ⅲ级,随机分为2组(n=10):右心房输注组(R组)和双心房输注组(B组).麻醉诱导后右颈内静脉穿刺置入Swan-Ganz三腔漂浮导管,监测CVP、PAP、肺毛细血管楔压(PCWP)和CO.R组经中心静脉输注前列腺素E130～150 ng·kg-1·min-1和去氧肾上腺素0.2～0.6μg·kg-1·min-1.B组经中心静脉输注前列腺素E130～150 ng·kg·min-1,经左心房输注去氧肾上腺素0.2～0.6μg·kg-1·min-1.分别于给药前5 min(T0)、给药后5 min(T1)、10 min(T2)、30 min(T3)和60 min(T4)时记录MAP、HR、MPAP、PCWP、CVP和CO,计算肺血管阻力指数(PVRI)、体循环血管阻力指数(SVRI)和CI.结果 与T0时比较,R组T1-4时MAP、MPAP、PCWP和PVRI降低,CI升高(P＜0.05),HR、CVP和SVRI差异无统计学意义(P＞0.05),B组T1-4时MAP、CI和SVRI升高,HR、MPAP、PCWP、CVP和PVRI降低(P＜0.05);与R组比较,B组MAP、CI和SVRI升高,HR、MPAP、PCWP、PVRI和CVP降低(P＜0.05).结论 双心房输注可降低二尖瓣置换术患者体外循环后肺动脉压和肺血管阻力.     

不同射血分数患者非体外循环冠状动脉旁路移植术中右心功能变化

目的研究不同射血分数患者非体外循环冠状动脉旁路移植术(OPCABG)术中右心功能变化规律。方法选择50例择期行OPCABG的患者,ASAⅡ或Ⅲ级,其中EF≥50%组30例,EF≤35%组20例,麻醉诱导后放置肺动脉导管,分别记录开心包后(基础值)、前降支(LAD)搭桥、回旋支(LCX)搭桥、后降支(PDA)搭桥及关胸骨后的CVP、平均肺动脉压(MPAP)、肺动脉楔压(PAWP)、心脏指数(CI)、右室射血分数(RVEF)、右室舒张末容积指数(RVEDVI)等。结果与基础值比较,LAD、LCX、PDA搭桥两组CVP、MPAP、PAWP明显升高(P<0.05);LCX、PDA搭桥两组CI、RVEF明显降低(P<0.05);而EF≥50%组RVEDVI明显降低、EF≤35%组RVEDVI明显升高(P<0.05)。与EF≤35%组比较,LCX、PDA搭桥、关胸后EF≥50%组RVEF明显升高(P<0.05);而LCX、PDA搭桥EF≥50%组RVEDVI明显降低(P<0.05)。结论在OPCABG术中行LCX和PDA搭桥期间可见右心功能受限,而不同射血分数患者之间右心功能变化规律有不同。     

非体外循环冠脉搭桥术中心脏移位对血液动力学的影响

目的 观察非体外循环冠脉搭桥术(OPCABG)中暴露术野时心脏位置改变对心血管功能的影响。方法 冠心病多支病变患者47例,年龄50～82岁,术前左室射血分数为0.55±0.14,择期行OPCABG,平均移植血管桥3.2条。采用漂浮导管方法监测血液动力学,分别在麻醉诱导后循环稳定时(T_1)、搬动心脏前(T_2)、吻合前降支时(T_3)、吻合右冠状动脉或后降支时(T_4)、吻合左旋支或对角支时(T_5)、血管吻合完成、心脏恢复自然位置后(T_6)、及手术结束时(T_7)作参数测定。结果 吻合前降支时(T_3),SI和LVSWI有所降低(P<0.01),但CI和SvO_2保持在基础水平。吻合后降支或右冠状动脉、左旋支或对角支时(T4、T5),CI、SI、LVWI、LVSWI、RVWI和RVSWI等明显降低(P<0.01),其中CI较对照值降低18％,LVWI和RVWI降低均为25％,MAP和SvO_2也显著下降(P<0.05～0.01),而HR、RAP、MPAP、PAWP和PVRI则显著增高(P<0.05～0.01)。心脏恢复自然位置后(T_6),CI、LVWI和RVWI恢复到对照值水平。结论 OPCABG术中由于心脏被搬动及移位,可导致明显的心功能损害和血压下降;麻醉手术期间采取可靠的血液动力学监测和有效的心血管功能支持十分必要。     

采用Swan-Ganz导管评价肝硬化患者肝移植术前心功能的状态

目的 采用Swan-Ganz导管评价肝硬化患者肝移植术前心功能的状态.方法 择期拟行原位肝移植术患者60例,年龄45～64岁,ASAⅡ-Ⅳ级,按术前肝功能状态分为2组:肝硬化代偿组(C组,n=28)和肝硬化失代偿组(H组,n=32).静脉注射咪达唑仑、异丙酚、维库溴铵和芬太尼麻醉诱导,气管插管后行机械通气,维持P_(ET)CO_2 30～45 mm Hg;吸入异氟醚,间断静脉注射芬太尼,静脉输注维库溴铵维持麻醉.常规监测HR,麻醉诱导后桡动脉穿刺置管,监测MAP;右侧颈内静脉置入Swan-Ganz漂浮导管,监测心输出量(CO)、心指数(CI)、右室射血分数(RVEF)、平均肺动脉压(MPAP)、肺动脉楔压(PAWP)、右房压(RAP)、右心室舒张末期容积(RVEDV)、右心室收缩末期容积(RVESV)和心搏指数(SVI),计算右室每搏功指数(RVSWI)、左室每搏功指数(LVSWI)、体循环血管阻力(SVR)和肺循环血管阻力(PVR).结果 与C组比较,H组HR、MAP、RAP和RVEF差异无统计学意义(P>0.05),CO、CI、SVI、MPAP、PAWP、RVEDV、RVESV、RVSWI和LVSWI升高,SVR和PVR降低(P<0.05).结论 原位肝移植术前肝硬化失代偿患者处于高排低阻状态,肺动脉压升高,心脏收缩功能和舒张功能降低,应加强心脏功能的保护.     

60岁以上男性多支冠状动脉病变旁路移植术后血流动力学研究

目的研究60岁以上男性多支冠状动脉病变旁路移植术后早期血流动力学的变化。方法对20例60岁以上男性体外循环下多支冠状动脉病变旁路移植术患者术前及术后血流动力学变化进行监测。结果术后2～6小时心脏指数（CI）、每搏指数（SVI）明显降低（P〈0.05）,肺循环指数（PVRI）、体循环指数（SVRI）明显升高（P〈0.05）;24～48小时后心功能明显改善,CI、左室每搏做功指数（LVSWI）明显增高（P〈0.05）。结论多支冠状动脉病变旁路移植术后早期CI明显下降,术后24小时内应有效降低体循环阻力,以降低左心室后负荷并以此增强左心室收缩功能及心排出量     

全麻联合硬膜外阻滞下经典式原位肝移植术期间血流动力学的改变

目的 观察全麻联合硬膜外阻滞行经典式原位肝移植期间血流动力学的变化.方法 24例肝癌全麻联合硬膜外阻滞下行经典式原住肝移植术,麻醉前放置Swam-Gaze导管,右桡动脉导管及右股静脉导管,监测麻醉前期,切皮时,无肝前期末,无肝期5 min,无肝期30 min,新肝期15 min及术毕各个时期血流动力学参数,用t检验组间变化的差异性.再分别以麻醉前作时照处理数据.结果 24例肝癌患者均行经典式原位肝移植术,手术时间(435±48)min,术中出血量(2 258±325)ml.术中输库存浓缩RBC(6.6±1.5)U、血浆(785±68)ml、平衡液(1 856±86)ml、血浆代用品(1 625±115)ml.①切皮时,中心静脉压(CVP),股静脉压(FVP),平均肺动脉压(MPAP),肺毛细血管楔压(PCWP)下降(P≤0.05或P≤0.01),心输出量(CO),心指数(CI)也随着降低(P≤0.05),MPAP降低(P≤0.05).②无肝前期末,CVP,FVP,MPAP,PCWP进一步下降(P≤0.01),CO和CI也随着进一步下降(P≤0.01),MPAP也进一步降低(P≤0.01).③无肝期5 min,CVP,MPAP,PCWP,CO,CI以及MPAP进一步剧烈下降(P≤0.01),即使周围血管阻力和肺血管阻力升高(P≤0.05),MPAP依然进一步剧烈下降(P≤0.01),但FVP骤然升高(P≤0.01).④无肝期30 min,股静脉压有所回落(P≤0.01),MPAP,PCWP,CO以及CI较无肝期5 min有回升趋势(P≤0.01).⑤新肝期,CVP,MPAP,PCWP,CO,CI以及MPAP明显回升(P≤0.01);周围阻力下降(P≤0.05),FVP骤然下降(P≤0.01).⑥手术结束时,CVP,FVP及MPAP较新肝期进一步回升(P≤0.01),其他指标如MAP,MPAP,PC聊,CO以及CI也基本上恢复至麻醉前水平(P≤0.05).FVP基本上和CVP相差不大(P≤0.05).结论 全麻联合硬膜外阻滞下原位肝移植术期间,协同麻醉作用,减少全身麻醉药对患者重要脏器的影响,扩张硬膜外阻滞区域血管,在门静脉和下腔静脉阻断时,可增加回心循环的血流量,部分代替体外静脉-静脉技术的作用,减少血流动力剧烈波动.     

双心房输注前列腺素E1和去氧肾上腺素对急性肺动脉高压犬血流动力学的影响

目的 观察双心房输注前列腺素E1和去氧肾上腺素对急性肺动脉高压犬血流动力学的影响.方法 15只杂种犬建立急性肺动脉高压模型后,随机均分为三组.A组通过Swan-Ganz导管至右心房给予前列腺素E1 20 ng·kg-1·min-1.通过左心导管至左心房给予去氧肾上腺素2μg·kg-1·min-1;B组经右心房给予和A组同样的两种药物和剂量;C组经右心房给予等容积的生理盐水.记录麻醉前(T0)、建模成功后10 min(T1)、20 min(T2)、给药后10 min(T3)、30 min(T4)、60min(T5)的HR、MAP、SpO2、CVP、平均肺动脉压(MPAP)、肺毛细血管楔压(PCWP)和心输出量(CO),计算心脏指数(CI)、肺循环阻力指数(PVRI)和体循环阻力指数(SVRI).结果 与C组比较,A、B组T3～T5时MPAP降低(P<0.05);与A组比较,B组T3～T5时CI、MAP和SVRI降低(P<0.05).结论 双心房分别输注前列腺素E1和去氧肾上腺素能降低急性肺动脉高压犬的MPAP,改善心功能.     

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.