等效剂量曲马多、吗啡或芬太尼用于老年病人术后静脉镇痛的临床研究

目的　研究等效剂量曲马多、吗啡或芬太尼用于老年病人术后静脉镇痛的临床疗效。方法　 12 0例老年病人 ,随机分为三组 ,每组 4 0例。术后病人第 1次感到疼痛时 ,给予等效初始量曲马多 1 5mg/kg(T组 )、吗啡 0 15mg/kg(M组 )、芬太尼 1 5 μg/kg(F组 )静注 ,然后分别持续静注曲马多 10mg·2ml-1·h-1、吗啡 1mg·2ml-1·h-1或芬太尼 10 μg·2ml-1·h-148小时。记录镇痛期间 1、2、3、4、6、12、2 4、4 8小时静息及活动时疼痛VAS值 ;监测用药前及用药后 10、2 0、30分钟、用药后 1、2小时的RR、SaO2 变化及各种不良反应。结果　三组病人静息时镇痛效果无明显差异 (P >0 0 5 )。前 4小时活动时M组、F组镇痛效果较T组优 (P <0 0 5 ) ;用药后 10、2 0分钟M组、F组RR明显减慢 ,与用药前相比差异显著 (P <0 0 5 ) ,所有病例用药前与用药后SaO2 均保持正常 ;恶心、呕吐的发生率T组明显高于M组、F组 (P <0 0 5 )。结论　连续静注等效剂量曲马多、吗啡或芬太尼用于老年病人术后镇痛均能取得满意的镇痛效果 ,但活动时吗啡和芬太尼的镇痛效果优于曲马多 ;吗啡和芬太尼于首次用药后能引起短暂的呼吸抑制 ,但在持续给氧时SaO2 仍保持正常     

氟比洛芬酯与曲马多用于子宫动脉栓塞下刮宫术后镇痛效果的观察

目的观察氟比洛芬酯和曲马多用于因子宫瘢痕妊娠行子宫动脉栓塞下刮宫术后患者静脉自控镇痛的效果。方法子宫瘢痕妊娠患者54例,拟行子宫动脉栓塞下刮宫术,随机均分为三组:F组(氟比洛芬酯),负荷量1mg/kg,按压剂量5mg,输注剂量7.5mg/h;T组(曲马多),负荷量1mg/kg,按压剂量10mg,输注剂量15mg/h;C组(生理盐水),负荷量5ml,按压剂量2ml,输注剂量3ml/h;记录刮宫术前和苏醒后1、4、8、12、24h的HR、MAP、VAS评分、24h内按压次数和恶心呕吐。结果各时点HR、MAP、VAS评分和按压次数F组和T组比较差异无统计学意义,但与C组比较,F、T组HR减慢,MAP降低(P<0.05),按压次数和VAS评分均显著降低(P<0.01)。三组间恶心呕吐发生率差异无统计学意义。结论氟比洛芬酯与曲马多用于子宫动脉栓塞下刮宫术后镇痛效果良好。     

曲马多复合芬太尼在口腔颌面部手术术后镇痛中的平衡应用

目的　观察静脉曲马多与芬太尼在口腔颌面部手术后镇痛的临床效果及不良反应。方法　ASAⅠ～Ⅱ级 6 0例择期行口腔颌面部手术病人 ,随机分为两组 ,曲马多组 (T组 )和芬太尼组(F组 ) ,每组 30例。T组 :曲马多 4 0 0mg+芬太尼 0 4mg +氟哌利多 2 5mg;F组 :芬太尼 2 0mg +氟哌利多 2 5mg ,均以生理盐水配置 10 0ml药袋 ,给予负荷剂量 4ml后连接ACEMedical镇痛泵进行自控镇痛 (PCA)。术后行 2、8、2 0、4 4hVAS评分 ,并对有效按压次数、用药量及不良反应发生情况进行了观察比较。结果　两组VAS评分、有效按压次数、用药量均无显著差异 (P >0 0 5 ) ,不良反应发生率F组明显高于T组。结论　曲马多与芬太尼联合应用于口腔颌面部手术的术后镇痛与芬太尼单独应用效果相当 ,但不良反应发生率明显低于后者 ,是一种更安全、有效的平衡镇痛方法     

布托啡诺术后静脉镇痛对血浆5-羟色胺、P物质和肾上腺素的影响

目的观察布托啡诺用于术后静脉自控镇痛对血清致痛物质5-羟色胺(5-HT)、P物质(PS)和肾上腺素(E)的影响。方法全麻手术患者30例随机均分为布托啡诺组(B组)、吗啡组(M组)和对照组(D组)。B组布托啡诺浓度0.006%,给药速率为0.0024 mg.kg-1.min-1,负荷剂量为0.005 mg/kg,每次有效按压给药0.003 mg/kg,锁定间隔时间10 min。M组吗啡浓度为0.025%,给药速率为0.005 mg.kg-1.min-1,负荷剂量为0.05 mg/kg,每次有效按压给药0.03 mg/kg,锁定间隔时间10 min。D组在患者需求时给予肌注吗啡10 mg。分别于麻醉诱导前(T0)、术后12 h(T1)、24 h(T2)、36 h(T3)、48 h(T4)采集肘静脉血3 ml,采用酶联免疫吸附测定法测定血清中5-HT、PS和E水平。结果B、M组T1~T4时5-HT、PS和E水平均低于D组(P<0.05)。结论布托啡诺静脉自控镇痛能抑制术后血清致痛物质5-HT、PS和E水平的升高,在一定程度上减弱痛觉信息传递,减轻机体应激反应。     

曲马多用于小儿术后镇痛最佳剂量的研究

目的　探讨曲马多用于小儿术后镇痛的最佳剂量。方法　全身麻醉下择期手术患儿77例 ,年龄 1月～ 13岁 ,随机分为七组 :术毕经硬膜外注入曲马多负荷量 1mg/kg、维持量 0 15mg·kg 1·h 1(E1组 ) ;1 5mg/kg、0 2 2 5mg·kg 1·h 1(E1 5组 ) ;2mg/kg、0 3mg·kg 1·h 1(E2组 ) ;2 5mg/kg、0 375mg·kg 1·h 1(E2 5组 ) ;或静脉注入 1mg/kg、0 15mg·kg 1·h 1(I1组 ) ;1 5mg/kg、0 2 2 5mg·kg 1·h 1(I1 5组 ) ;2mg/kg、0 3mg·kg 1·h 1(I2组 )。选择持续输注加PCA给药模式 ,持续镇痛 4 8h。记录疼痛、镇静评分、曲马多用量、PCA按压次数、有效按压率 (D/D)及不良反应发生率。结果　曲马多用量依次为 :E2 5组 >E2组 >E1 5组 >E1组 ,I2组 >I1 5组 >I1组 (均P <0 0 1)。按压次数 :E1 5组明显少于E1组 (P <0 0 5 ) ,也明显少于I1 5组 (P <0 0 5 ) ,其余各组间无显著性差异。有效按压率 (D/D) :相同途径各组间均无显著差异。疼痛评分 :E2组明显低于E1组(P <0 0 5 ) ,其余各组间均无统计学意义。镇静评分及不良反应发生率各组间的差异均无统计学意义。结论　曲马多用于小儿术后镇痛 ,无论硬膜外途径还是静脉途径 ,负荷量 1 5～ 2mg/kg、维持量0 2 2 5～ 0 3mg·kg 1·h 1较为适宜     

吗啡-芬太尼复合麻醉下非体外循环冠状动脉旁路移植术患者的转归

目的 探讨吗啡-芬太尼复合麻醉下非体外循环下冠状动脉旁路移植术患者的转归.方法 拟在非体外循环下行冠状动脉旁路移植术的患者72例,年龄41～64岁,随机分为2组(n=36):芬太尼复合麻醉组(F组)和吗啡-芬太尼复合麻醉组(MF组).静脉注射芬太尼10～20μg/kg、咪达唑仑0.1 mg/kg、依托咪酯0.3 mg/kg和维库溴铵0.1 mg/kg进行麻醉诱导,气管插管后行机械通气.麻醉维持:MF组静脉输注吗啡0.15 mg·kg-1·h-1+芬太尼8μg·kg-1·hZ-1,F组静脉输注芬太尼10μg·kg-1·h-1,2组均吸入0.5%～2.0%异氟烷,间断静脉注射维库溴铵4 rag.2组术后进行静脉镇痛,MF组和F组分别静脉输注吗啡0.75 mg/h吗啡和芬太尼10μg/h.分别于术前(基础状态)、术后1、2、3 d进行恢复质量评分(QoR评分).于拔除气管导管后15 min、4 h、24 h时进行Ramsay镇静评分.记录术后不良反应的发生情况.结果 与F组比较,MF组术后QoR评分升高,术后发热发生率降低(P＜0.05或0.01),Ramsay镇静评分和其他不良反应的发生率差异无统计学意义(P＞0.05).结论与芬太尼复合麻醉比较,吗啡-芬太尼复合麻醉有利于非体外循环下冠状动脉旁路移植术患者预后.     

术中负荷剂量曲马多对术后吗啡PCA效果的影响

目的　研究术中负荷剂量曲马多的使用对术后吗啡病人自控镇痛 (PCA)效果的影响。方法　 6 0例腹部手术患者 ,采用随机、双盲、对照试验的方法于手术结束前静脉给予生理盐水 (对照组 )、1mg/kg曲马多或 2mg/kg曲马多。术后使用吗啡静脉PCA进行镇痛。观察术后镇痛效果及不良反应。结果　曲马多组与对照组比较 ,术后清醒时间、拔管时间、术后呼吸次数和血氧饱和度均无显著差异。 2mg/kg曲马多组在给药后 1小时和 8小时VAS评分分别为 (1 33± 1 4 6 )分和 (1 5 4±1 6 5 )分 ,对照组分别为 (2 78± 1 87)分和 (2 6 1± 2 0 6 )分 (P <0 0 1,P <0 0 5 )。结果还显示 ,术毕给予 2mg/kg曲马多可明显减少术后PCA的吗啡用量及补救吗啡用量。 结论　术中使用 2mg/kg负荷剂量的曲马多可有效改善术后吗啡PCA的镇痛效果 ,并可减少PCA吗啡和补救吗啡用量。同时 ,曲马多的使用对术毕的清醒时间和呼吸恢复没有明显影响     

术前口服曲马多缓释剂对瑞芬太尼复合麻醉病人术后急性阿片类药物耐受的影响

目的 评价术前口服曲马多缓释剂对靶控输注瑞芬太尼复合麻醉病人术后急性阿片类药物耐受的影响.方法 择期拟行腹腔镜胆囊切除术病人60例,ASA Ⅰ或Ⅱ级,年龄18～64岁,随机分为2组(n=30):安慰剂组(C组)和曲马多组(T组).C组于术前48、36、24、12、0.5 h时口服维生素C片1片(100 mg),T组于相同时点口服曲马多缓释片1片(100 mg),共计500 mg.两组均采用靶控输注瑞芬太尼和异丙酚复合麻醉,拔除气管导管后在麻醉恢复室(PACU)观察1h送返病房.PACU内静脉注射芬太尼5～10μg,5 min后重复注射,维持VAS评分＜4分.病房内采用10 μg/ml芬太尼100 ml行PCIA(负荷量10μg、背景输注速率20 μg/h、PCA剂量5μg、锁定时间15 min).记录PACU内芬太尼用量、术后48 h内PCIA芬太尼用量、有效按压次数(D_1)和实际按压次数(D_2),计算D_1/D_2比值.结果 与C组比较,T组术后PACU内芬太尼用量减少(P＜0.05),术后48 h内PCIA芬太尼用量和D_1/D_2比值差异无统计学意义(P＞0.05).结论 术前口服500 mg曲马多缓释剂可减轻靶控输注瑞芬太尼复合麻醉病人术后急性阿片类药物耐受.     

吗啡、芬太尼、曲马多术后镇痛对病人白细胞介素-2的影响

目的 观察吗啡、芬太尼、曲马多用于术后病人静脉自控镇痛(PCIA)时对血清白细胞介素-2(IL-2)分泌的影响。方法 150例择期行上腹部手术的病人，随机分成三组：M组(吗啡组)；F组(芬太尼组)；T组(曲马多组)。分别于麻醉前、术后1、3、24h采血，应用酶联免疫吸附试验(ELISA)检测血清IL-2水平。结果 与麻醉前比较，M组病人术后各时点血清IL-2水平明显降低(P＜0．05)，F组在各时点明显升高(P＜0．05)，T组术后1h与麻醉前比较差异无显著性(P＞0．05)，术后3h明显升高(P＜0．05)，术后24h达到更高水平(P＜0．01)。结论 吗啡、芬太尼、曲马多均可有效减轻术后疼痛。与吗啡抑制IL-2分泌相反，芬太尼和曲马多可明显增强上腹部手术病人术后IL-2的分泌。     

氯胺酮复合曲马多病人自控静脉镇痛用于肝功能不全患者术后镇痛

目的　研究小剂量氯胺酮复合曲马多应用于肝功能不全患者术后病人自控静脉镇痛(PCIA)的可行性和安全性。方法 4 0例肝炎后肝硬化合并脾功能亢进需行脾切除术的患者 ,ASAⅡ～Ⅲ级 ,随机等分为T组 (曲马多 15 0 0mg、恩丹西酮 8mg加生理盐水至 15 0ml)、TK组 (曲马多12 0 0mg、氯胺酮 30 0mg、恩丹西酮 8mg加生理盐水至 15 0ml)。两组持续输注速度 0 0 3ml·kg 1·h 1,首剂为 0 1ml/kg ,单次PCA给药剂量 2ml,锁定时间 15min。记录术后第 2、4、8、16、2 4、36、4 8、72h的VAS评分、PCIA用药量、PCA总按压次数 /有效按压次数 (D/D)、呼吸和循环的状况以及不良反应的发生情况。结果　两组患者一般情况相同 ,术后第 3天的肝功能与术前相比无显著差异 (P >0 0 5 )。两组患者呼吸通畅 ,SpO2 均在 96 %以上。在术后 36h内TK组的VAS评分、用药量、D/D明显低于T组 (P <0 0 1) ,36h以后无显著差异 (P >0 0 5 ) ;两组患者的并发症发生率无显著差异 (P >0 0 5 )。结论　小剂量氯胺酮复合曲马多可以改善镇痛效果 ,明显减少曲马多的用量 ,可以安全有效地应用于肝功能不全的患者术后静脉镇痛     

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.     

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.     

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.     

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.