双侧肾细胞癌21例报告

目的 探讨双侧肾细胞癌手术治疗的疗效。方法 1990年1月至2005年1月收治双侧肾细胞癌患者21例。其中同时性10例，异时性11例。肿瘤位于肾上极15枚，中极19枚，下极20枚；左肾28枚，右肾26枚。肿瘤直径0．5～16．0cm，平均4．5cm。2例伴下腔静脉癌栓。17例经手术治疗。6例同时性肾癌中，5例行双侧一期手术，1例行分期手术。其中1例行双肾部分切除术；1例行双肾部分切除及左肾上腺切除术；3例行一侧肾癌根治术及对侧肾部分切除术；1例行一侧肾癌根治术，对侧肾部分切除术及下腔静脉切开取癌栓术。11例异时性肾癌均分期手术。其中3例行双肾部分切除术；1例行一侧肾癌根治术，对侧肾肿瘤剜出术；1例行一侧肾癌根治术，对侧肾部分切除术加下腔静脉切开取癌栓术；6例行一侧肾癌根治术，对侧肾部分切除术。未行手术治疗4例．其中行介入治疗1例，生物学治疗1例，保守治疗2例。结果 21例随访3个月～24年，平均3．4年。17例手术治疗者中，13例未见肿瘤复发和转移，术后肾功能均可；1例术后10个月出现左上肺转移，已带瘤存活9个月；1例术后1年出现残肾肿瘤复发，经生物学和中药治疗，已带瘤存活5个月；2例死于肿瘤转移。4例未手术者中，1例10个月后死于胰腺转移，1例4个月后死于肾衰竭，1例6个月后死于脑血管意外，1例伴腹膜后淋巴结转移者经化疗和生物学治疗，病情稳定，已带瘤存活7个月。异时性肾癌者的先发一侧行肾癌根治术，对侧肾出现肿瘤的时间为7个月～18年。结论 双侧肾癌并非手术禁忌，如果采取积极的治疗措施，仍可获得满意的手术效果。保肾手术是目前较为理想的治疗方法，如果保留足够的肾实质，患者仍可获得良好的生存状态。     

双侧肾癌的诊治与预后（附6例报告）

目的：探讨双侧肾癌（Bilateral renal cell carcinoma,BRCC）患者的诊治与预后。方法：1999年1月～2006年1月我院共诊治BRCC患者6例,平均发病年龄53（35～74）岁。其中双侧同时性肾癌3例,异时性肾癌3例。肿瘤位于肾上极6枚,中极7枚,下极1枚;左肾6枚,右肾8枚;肿瘤平均直径4．6（3～7）cm。3例同时性肾癌患者,2例行双侧同期手术,1例行分期手术。其中2例行一侧肾癌根治术,对侧保留肾单位手术（NSS）;1例一侧先行NSS,2周后再行对侧肾癌根治术。3例异时性肾癌患者均行分期手术治疗,均行一侧肾癌根治术,对侧NSS术。结果：6例随访12～156个月,平均84．5个月。肿瘤转移2例,分别死于肺转移和骨转移;肿瘤局部复发2例;无瘤生存2例。结论：NSS是目前较为理想的双侧肾癌治疗方法。治疗双侧肾癌的原则为尽可能切除肿瘤和最大限度保存。肾功能。     

同时性散发性双肾癌的手术治疗策略研究

目的:探讨同时性散发性双侧肾癌的手术治疗策略。方法:回顾性分析64例同时性散发性双肾癌患者的临床及病理资料。男47例,女17例,年龄25~69岁,平均51岁。59例患者无任何临床症状为体检时发现,2例以血尿就诊,3例以腰痛就诊,均未伴淋巴结及远处转移。肿瘤临床分期为T1a38例,T1b17例,T2a9例。结果:64例患者均行后腹腔镜手术治疗。4例患者行双侧肿瘤的同期手术切除,2例发生术后急性肾功能衰竭,行短期透析治疗。60例行双侧肿瘤分期手术切除,其中33例行双侧保留肾单位手术(NSS-NSS组),19例先行一侧根治性肾切除术后行另一侧保留肾单位手术(RN-NSS组),7例先行保留肾单位手术后行另一侧根治性肾切除术(NSS-RN组)。双侧肿瘤切除术后各组肌酐分别为89、110、102μmol/L。1例行双侧根治性肾切除,术后行常规透析治疗。术后随访7~99个月,中位随访时间49个月,50例患者无瘤生存,2例局部复发,5例发生转移,7例死亡。结论:后腹腔镜分期保留肾单位手术是同时散发性双肾癌的首选治疗策略,在完整切除肿瘤的同时最大限度的保留肾功能。患者预后不因双侧肾脏受累而受到明显影响。     

双侧肾同时发生肾细胞癌的保肾手术治疗

目的评价保肾手术在双侧肾癌治疗中的作用。方法报告一组双侧肾同时发生的肾细胞癌行保肾手术治疗结果。１９９０～１９９６年５例双侧Ⅱ期肾细胞癌，肾肿瘤直径１．５～５．５ｃｍ，平均４．０ｃｍ；共１３枚肿瘤，其中４例２枚，１例５枚。３例一侧作肾根治性切除，一侧作保肾手术，２例双侧肾均作保肾手术。结果平均随访３０个月，１例术后３年发现肺转移，无１例局部复发。结论保肾手术对体积较小的双肾癌是安全有效的治疗方法。     

不同病理类型双侧肾癌5例临床分析

目的探讨不同病理类型双侧肾癌(BRCC)的临床病理特点、手术治疗策略和预后。方法回顾性分析2004年6月至2019年6月北京大学第三医院收治的5例不同病理类型BRCC患者的临床资料。5例均为男性,平均年龄53(33～61)岁。同时性BRCC 3例,异时性BRCC 2例。5例均为双侧单发肿瘤。10枚肿瘤中实性肿瘤3枚,囊性肿瘤7枚。肿瘤平均直径2.4(1.4～6.7)cm。平均R.E.N.A.L.评分5(4～8)分。5例患者术前平均血清肌酐79(74～108)μmoI/L。结果 5例均成功行双侧手术治疗:其中3例行双侧后腹腔镜下保留肾单位手术(NSS);1例行一侧后腹腔镜下根治性肾切除术(RN),对侧后腹腔镜下NSS;1例因一侧囊性肿瘤体积较大,粘连严重行后腹腔镜探查,中转开放NSS,对侧后腹腔镜下NSS。3例同时性BRCC患者均采用分期手术策略,双侧手术平均间隔时间3(1.5～4)个月。5例平均手术时间126(110～221)min,行NSS者平均热缺血时间24(11～40)min。平均手术失血量20(10～50)mL。5例患者术后平均血清肌酐95(77～121)μmol/L,术后平均住院时间6(3～16)d。术后病理示5例均为一侧肾透明细胞癌,其中对侧低度恶性潜能多房囊性肾肿瘤者3例、肾嫌色细胞癌者1例、管状囊性肾细胞癌者1例。5例平均随访时间26.7(18.6～194.3)个月,均无局部复发或远处转移,肾功能良好。结论不同病理类型BRCC临床较为罕见,治疗以分期双侧NSS为首选。腹腔镜下NSS治疗复杂性肾囊性肿瘤难度较大,需临床经验丰富的医师进行操作。BRCC多灶发病的概率显著高于单侧肾癌,术后应严密随访,不同病理类型BRCC的预后取决于恶性度较高、分期较晚的一侧。同一机体发生不同病理类型的BRCC,为该病的肿瘤起源研究提供新的线索和思路,但BRCC的发生机制尚需基因测序的大样本研究进一步阐明。     

肾癌保留肾单位手术的临床价值(附17例报告)

目的　评价肾癌保留肾单位手术的临床价值。　方法　回顾性研究 17例行保留肾单位手术的肾癌患者临床资料 ,其中单侧 15例 ,双肾异时性肾癌且一侧为多发肿瘤 2例。绝对指征 2例 ,相对指征 6例 ,选择性指征 9例。肿瘤直径 2～ 6cm ,均为T1期 (1997年TNM标准 ) ;行改良肾肿瘤剜除术 (切缘于肾肿瘤外 1cm正常肾实质处 ) 15例 ,肾上极切除术 1例 ,楔形切除术 1例。 2 0例同期肾癌临床及分期相当但行根治性手术的患者资料作随访对照 ,并作生存率时序检验。　结果　 17例患者随访 3～ 6 3个月 ,平均 35 .2个月 ,未见并发症及残肾肿瘤复发。无瘤生存率与根治性手术者相近。　结论　肾癌保留肾单位手术安全、有效 ,适合于对侧肾功能正常、一侧局限的偶发肾肿瘤患者。     

von Hippel-Lindau病的肾脏病理学特点

目的 探讨von Hippel—Lindau(VHL)病肾脏损害的病理特点及VHL多发性肾癌的治疗。方法 回顾性分析6例同一VHL病家族伴有肾脏损害患者的临床及病理资料；1例为双肾多发性囊肿，5例为双侧肾癌伴多发性囊肿。结果 5例双肾癌10侧肾脏中，行保留肾单位手术5侧，肾癌根治术3侧，带瘤随访2侧。1例多发肾囊肿者仅随诊观察。术后病理实质性肿块均为透明细胞癌。Fuhrman分级结果：Ⅰ级14枚，Ⅱ级6枚。TNM病理分期：T1N0M04例、T2N0M01例。切除14枚可疑的肾囊肿，术后病理恶性囊肿1枚，余为单纯囊肿。术后随访9～113个月，平均47个月，5例患者均存活且无肿瘤复发及远处转移；5例肾功能正常，1例肾功能较术前差，但无需血透治疗。结论 VHL病中肾脏损害包括肾癌及肾囊肿，常为双侧多发性，肿瘤为透明细胞癌且分级分期低。保留肾单位手术是治疗VHL病中肾癌的有效方法。     

老年患者双肾肿瘤的半保守治疗

目的:评价老年双肾肿瘤半保守治疗安全性。方法:对6例老年双肾肿瘤患者的临床资料进行回顾性分析。6例共12枚肿瘤,每例患者肿瘤均一大一小,影像学均高度怀疑肾癌。大肿瘤直径4.5~10.0cm,平均7.0cm均行根治性切除;小肿瘤直径1.8~2.7cm,平均2.3cm,予保守治疗。结果:手术均未发生严重的并发症,6例大肿瘤均为肾细胞癌:5枚混合细胞癌(以透明细胞为主型),分级Ⅱ级4枚、Ⅰ级1枚;1枚嫌色细胞癌,分级Ⅰ级。随访12~45个月,平均34个月,小肿瘤体积平均每年增大2.96(1.15~8.66)cm3,无局部浸润征象。手术侧未见复发,亦未见远处转移。结论:老年双肾肿瘤(一侧大肿瘤一侧小肿瘤)患者半保守治疗安全、有效。     

von Hippel-Lindau综合征外科治疗

目的 探讨von Hippel-Lindau(VHL)综合征的外科治疗方法.方法 VHL综合征患者4例.例1,男,56岁.主诉乏力、心悸2 d.空腹血糖2.37 mmol/L.CT检查示左肾上、下极3个肿块,直径分别为8.0、7.0、4.0 cm.10年前行脑血管母细胞瘤切除术.例2,女,57岁.主诉左腰痛不适1个月.CT检查示左肾上腺、左肾、胰体肿物,直径分别为2.7、4.5、2.1 cm.例3,女,39岁.查体发现左肾上腺占位1个月.CT检查示左肾上腺3.0 cm×4.0 cm实性占位,增强后肿块明显强化.既往有小脑、脊髓血管母细胞瘤及双侧肾癌手术史.例4,女,41岁.B超发现双肾肿瘤1个月入院.CT检查示左肾、左肾上腺、右肾、胰腺肿物,直径分别为4.0、3.0、1.5、2.0 cm.1个月前行y刀治疗多发脑部肿瘤.结果 4例均手术治疗.例1行左肾根治性切除术,病理报告肾血管周细胞瘤,随访6个月右肾未见异常.例2行左肾、左肾上腺、胰体尾及脾切除,病理报告肾透明细胞癌、胰岛细胞瘤、肾上腺囊肿,随访3个月MRI检查发现脊髓肿瘤.例3行左肾上腺肿瘤摘除术,病理报告嗜铬细胞瘤,随访2年未见肿瘤复发.例4行左肾、左肾上腺切除,病理报告肾透明细胞癌、肾上腺嗜铬细胞瘤,3周后剜除右肾肿瘤,病理报告透明细胞癌,随访1年肿瘤未复发.结论 VHL可并发多器官肿瘤,较大中枢神经系统肿瘤可手术切除,多发较小的实性肿瘤可放疗.直径<3cm肾癌可密切随访、择期处理;直径>3cm肾癌首选保留肾单位手术.肾上腺肿瘤首选腺瘤摘除术,避免肾上腺全切术.腹部多器官肿瘤一期手术安全可行. 理报告肾透明细胞癌、胰岛细胞瘤、肾上腺囊肿,随访3个月MRI检查发现脊髓肿瘤.例3行左肾上腺肿瘤摘除术,病理报告嗜铬细胞瘤,随访2年未见肿瘤复发.例4行左肾、左肾上腺 除,病理报告肾透明细胞癌、肾上腺嗜铬细胞瘤,3周后剜除右肾肿瘤,病理报告透明细胞癌,随访1年肿瘤未复发.结论 VHL可并发多器官肿瘤,较大中枢神经系统肿瘤可手术切除,多发较小的实性肿瘤可放疗.直径<3cm肾癌可密切随访、择期处理;直径>3cm肾癌首选保留肾单位手术.肾上腺肿瘤首选腺瘤摘除术,避免肾上腺全切术.腹部多器官肿瘤一期手术安全可行. 理报告肾透明细胞癌、胰岛细胞瘤、肾上腺囊肿,随访3个月MRI检查发现脊髓肿瘤.例3行左肾上腺肿瘤摘除术,病理报告嗜铬细胞瘤,随访2年未见肿瘤复发.例4行左肾、左肾上腺 除,病理报告肾透明细胞癌、肾上腺嗜铬细胞瘤,3周后剜除右肾肿瘤,病理报告透明细胞癌,随访1年肿瘤未复发.结论 VHL可并发多器官肿瘤,较大中枢神经系统肿瘤可手术切除,多发较小的实性肿瘤可放疗.直径<3cm肾癌可密切随访、择期处理;直径>3cm肾癌首选保留肾单位手术.肾上腺肿瘤首选腺瘤摘     

局限性肾癌保留肾单位手术20例分析

目的探讨保留肾单位手术（nephrom-sparing surgery,NSS）治疗局限性肾癌的安全性和疗效。方法回顾性分析20例行NSS肾癌患者的临床资料,其中双侧肾癌1例,孤立肾肾癌1例,对侧肾有病变或潜在功能损害的肾癌3例,对侧肾正常的肾癌15例。肿瘤直径平均3.9（1.3-7.4）cm。行肿瘤剜除术13例,肾部分切除术4例,肾楔形切除术3例。结果 20例患者手术均成功。术后平均随访29（15-37）个月,1例双侧肾癌患者术后14月出现远处转移死亡,1例术后12个月因局部复发改行根治性肾切除术,2例术后出现暂时性肾功能不全。结论 NSS治疗肾癌安全有效,尤其适用于局限性肾癌患者。     

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.