致敏患者经双滤过法血浆分离方案预处理后行肾移植的临床效果分析

目的 分析致敏患者经双滤过法血浆分离(DFPP)方案预处理,并联合使用抗CD25单抗诱导治疗后行肾移植的临床效果和安全性.方法 回顾性分析2000年11至2012年1月45例致敏受者在肾移植前经DFPP方案预处理,并联合使用抗CD25单抗诱导治疗后接受肾移植的临床资料.所有受者预处理前的群体反应性抗体(PRA)水平均大于20％,为(56.5±19.9)％,预处理后PRA水平降至(18.9±19.1)％.受者与供者的HLA抗原错配数为(2.1±0.7)个,术前2次供、受者淋巴细胞毒交叉配型试验均为阴性.所有受者术后至少随访1年,观察术后1年受者和移植肾存活率,以及排斥反应和肺部感染的发生情况.结果 随访期间,无受者死亡,有2例受者发生移植肾功能丧失,术后1年受者存活率为100％(45/45),移植肾存活率为95.6％ (43/45).术中肾血管开放后1例发生超急性排斥反应,发生率为2.2％,受者在切除移植肾后恢复血液透析;术后发生急性排斥反应12例,发生率为26.7％(12/45),经甲泼尼龙和(或)ATG冲击治疗后,11例完全逆转,1例出现移植肾功能丧失而恢复血液透析.术后肺部感染发生率为8.9％(4/45),经抗感染治疗后均好转,未发生重症肺部感染.结论 肾移植前采用DFPP 预处理,并联合使用抗CD25单抗诱导治疗安全有效,能使致敏受者获得良好的肾移植效果.     

肾移植前对致敏患者干预治疗的方案及疗效分析

目的 总结和探讨肾移植前致敏患者干预治疗的方案及疗效分析.方法 选择2008年至2011年接受肾移植的致敏受者43例,根据术前群体反应性抗体(PRA)水平分为轻度致敏组和高度致敏组,术前经血浆置换、输注静脉用免疫球蛋白(IVIG)的干预治疗,经过HLA配型,联合应用抗人胸腺细胞免疫球蛋白(ATG)诱导治疗,应用他克莫司(Tac)、吗替麦考酚酯(MMF)和泼尼松的免疫抑制方案,术后定期检测PRA水平.所有受者随访12～36个月,观察受者/移植肾存活率,急性排斥反应的发生率,移植肾功能和PRA水平的变化,以及进行移植肾穿刺活检.结果 经干预治疗后,轻度致敏组中14例PRA完全转阴,高度致敏组中5例PRA完全转阴,其余受者PRA水平均较干预治疗前明显下降(P＜0.05).术后两组受者均出现PRA水平的爬升.轻度致敏组和高度致敏组的人存活率分别为95.6％和90％,移植肾存活率分别为82.6％和70％.轻度致敏组有3例活检证实发生急性细胞性排斥反应,高度致敏组有5例活检证实发生急性排斥反应,急性细胞性排斥反应均经甲泼尼龙冲击治疗3～5 d后逆转.两组共10例受者出现血肌酐缓慢爬升,经移植肾穿刺活检发现慢性移植肾肾病的表现.结论 血浆置换和输注IVIG的干预治疗,良好的HLA配型,ATG诱导治疗,以及应用Tac+ MMF+泼尼松的免疫抑制方案是致敏受者肾移植成功的前提.     

不同抗体的诱导治疗在再次肾移植中应用效果的比较

目的 总结在再次肾移植中采用抗体进行免疫诱导的临床经验,并比较不同抗体的应用效果.方法 回顾分析39例再次肾移植受者的临床资料.39例受者均接受了免疫诱导,其中接受巴利昔单抗(Bax)者12例(Bax组),接受抗胸腺细胞球蛋白(ATG)者8例(ATG组),接受抗淋巴细胞球蛋白(ALG)者19例(ALG组).观察和比较各组间急性排斥反应(AR)、移植物功能丧失、巨细胞病毒(CMV)感染等发生率,以及术后1年时血清肌酐(SCr)水平和移植肾存活率.结果 Bax 组、ALG组和ATG组分别有41.7 ％(5/12)、47.4％(9/19)和12.5％(1/8)的受者发生AR,ATG组AR发生率明显低于Bax组和ALG组(P＜0.05),而Bax组和ALG组间的差异无统计学意义.39例移植肾1年总体存活率为84.6％,Bax组、ALG组和ATG组分别为82.4％、80.5％和90.8％,ATG组显著高于其他2组(P＜0.05);3组术后1年时SCr值分别为(176.8±43.5) μmol/L、(195.4±35.2) μmol/L、(121.3±22.6) μmol/L,ATG组的SCr水平显著低于其他2组(P＜0.0)5),而Bax组与ALG组间SCr水平的差异无统计学意义.Bax组、ALG组和ATG组CMV感染发生率分别为16.7％(2/12)、15.8 ％(3/19)和25％(2/8),3组间两两比较,差异均无统计学意义(P＞0.05).结论 再次肾移植受者具有较高的免疫风险因素及AR发生率,与Pax和ALT相比,ATG能更好的预防AR,改善移植肾功能,提高移植物早期(1年)存活率,并且不增加感染的发生风险.     

抗淋巴细胞制剂诱导治疗对肾移植后人、肾长期存活的影响

目的 探讨抗淋巴细胞制剂诱导治疗对肾移植后人、肾长期存活的影响.方法 271例首次接受尸体肾移植的受者,其中使用抗胸腺细胞球蛋白诱导治疗者110例(ATG组),使用巴利昔单抗诱导治疗者88例(Bax组),未接受诱导治疗者73例(对照组).所有受者术后采用他克莫司+吗替麦考酚酯+皮质激素的三联免疫抑制方案,并应用更昔洛韦预防CMV感染.术后对所有受者进行了1~5年的随访,观察和比较各组术后6个月内的并发症发生情况,以及术后1、3、5年的人、肾存活率.结果 ATG组、Bax组和对照组术后6个月AR的发生率分别为9.1 %(10/110)、10.2 %(9/88)和17.8 %(13/73),ATG组和Bax组间AR发生率的差异无统计学意义(P＞0.05),但均显著低于对照组(P＜0.05).3组间移植肾功能恢复延迟、CMV感染及非CMV感染等发生率的比较,差异均无统计学意义(P＞0.05).ATG组和Bax组术后1、3、5年移植肾存活率分别为95.5 %、90.9 %、87.3 %和93.2 %、87.5 %、83.8 %,均显著高于对照组的87.7 %、80.8 %、75.3 %(P＜0.05).结论 应用抗淋巴细胞制剂进行免疫诱导治疗可显著降低肾移植术后早期AR的发生率,并显著改善移植肾的长期存活率.

Abstract：

Objective To explore the impact of induction therapy with anti-lymphocyte agents on long-term survival of kidney transplantation.Methods 271 recipients of first cadaveric kidney transplants were treated with tacrolimus,mycophenolate mofetil and prednisone.110 patients of them received induction therapy with anti-thymocyte globulin(ATG group),88 patients received Basiliximab(Bax group),and the remaining 73 patients did not receive induction therapy(control group).The data of AR,DGF,CMV infection,and 1- 3- 5-year patient/allograft survival rate in three groups were retrospectively during a follow-up period of 1 to 5 years postoperatively.Results Within 6 months after operation,the incidence of AR in control group,ATG group and Bax group was 17.8 %(13/73),9.1 %(10/110)and 10.2 %(9/88)respectively.The incidence of AR in ATG group and Bax group was significantly lower than in control group (P<0.05).There was no significant difference in incidence of DGF and CMV infection among three groups.The 1-,3- and 5-year allograft survival rate postoperation in ATG group and Bax group was 95.5 %,90.9 %,87.3 % and 93.2 %,87.5 %,83.8 % respectively,which was significantly higher than in control group(87.7 %,80.8 % and 75.3 %,P<0.05).Conclusion Induction therapy with anti-lymphocyte agents may reduce the early incidence of AR and prolong long-term allograft survival significantly.     

阿来佐单抗对肾移植后急性排斥反应和移植肾存活率影响的荟萃分析

目的 探讨阿来佐单抗对肾移植后急性排斥反应(AR)和移植肾存活率的影响.方法搜集国内外关于阿来佐单抗用于预防肾移植后AR的随机对照试验,对符合纳入标准的文献进行荟萃分析.评价疗效及差异的指标采用比值比(OR)及其95％可信区间(CI).采用RevMan5.1软件进行统计学分析.结果 共有国内外9个随机对照研究符合纳入标准.荟萃分析结果显示,阿来佐单抗具有良好的抗AR作用,术后半年阿来佐单抗组的AR发生率比对照组低55.5％(OR=0.37,95％CI为0.24～0.58,P＜0.01),术后1年阿来佐单抗组的AR发生率比对照组低51.1％(OR=0.43,95％CI为0.29～0.64,P＜0.01),术后2年阿来佐单抗组的AR发生率比对照组低28.2％(OR=0.69,95％CI为0.47～1.02,P＜0.01).阿来佐单抗组的移植肾存活率与对照组比较,差异无统计学意义(OR=1.18,95％CI为0.76～1.85,P=0.46),阿来佐单抗组的受者存活率与对照组比较,差异无统计学意义(OR=0.94,95％CI为0.52～1.72,P=0.85).结论 阿来佐单抗对肾移植后AR具有明显的预防作用,但对术后移植肾和受者的存活率无明显影响.     

心脏死亡器官捐献肾移植两种免疫诱导方案疗效比较

目的比较在心脏死亡器官捐献(DCD)肾移植受者中分别应用IL-2受体拮抗剂(IL-2Ra)或抗胸腺细胞球蛋白(ATG)进行免疫诱导治疗的早期临床疗效,探讨DCD肾移植中如何选择合理的免疫抑制方案。方法回顾性分析2015年1月至2016年4月在武汉大学人民医院器官移植科完成的110例DCD供肾肾移植受者资料。其中应用IL-2Ra进行免疫诱导82例(IL-2Ra组),应用ATG进行免疫诱导28例(ATG组),所有受者均采用他克莫司+吗替麦考酚酯+糖皮质激素三联免疫抑制方案。两组受者术前及术后各时间点血清肌酐比较采用t检验。两组受者术后DGF、肺部感染、急性排斥反应(AR)发生情况以及移植肾/受者存活情况比较采用卡方检验。P0.05为差异有统计学意义。结果 IL-2Ra组和ATG组受者DGF发生率分别20.7%、42.9%,差异有统计学意义(χ2=5.263,P0.05),两组受者肺部感染、AR发生情况以及移植肾/受者存活比例差异均无统计学意义(P均0.05)。IL-2Ra组和ATG组肾移植受者术前及术后第90天血清肌酐水平差异无统计学意义(P均0.05),术后第1、2、4、7、14、21、30、60天血清肌酐水平差异均有统计学意义(P均0.05)。结论 IL-2Ra和ATG都能有效预防肾移植受者术后AR的发生,需综合考虑供、受者情况选择合适的免疫诱导药物。     

肾移植中应用IL-2受体拮抗剂与抗胸腺细胞球蛋白行免疫诱导的长期疗效比较

目的 比较肾移植中应用白细胞介素2受体拮抗剂(IL2Ra)与抗胸腺细胞球蛋白(rATG)行免疫诱导的长期疗效.方法 回顾性分析2006年至2010年间的371例肾移植受者,其中使用IL2Ra诱导治疗者261例(IL2Ra组),使用rATG诱导治疗者110例(rATG组).所有受者术后采用钙调磷酸酶抑制剂+吗替麦考酚酯+皮质激素的三联免疫抑制方案,并使用更昔洛韦预防巨细胞病毒感染,使用复方磺胺甲(恶)唑预防卡氏肺孢子虫感染.术后对所有受者随访了1～5年,观察和比较移植肾功能恢复延迟(DGF)、1年内急性排斥反应和感染的发生率,以及受者和移植肾长期存活率等.结果 两组间受者性别、年龄、原发病等资料的差异均无统计学意义(P＞0.05),但与IL2Ra组比较,rATG组受者接受的供肾更多来源于尸体供肾(P＜0.01),且供肾冷缺血时间较长(P＜0.01).IL2Ra组和rATG组术后DGF发生率分别为3.1％和1.8％(P＞0.05),术后1年内急性排斥反应发生率分别为10.7％和2.7％ (P＜0.05),感染发生率分别为14.9％和21.8％ (P＞0.05).术后1、2和3年,IL2Ra组受者存活率分别为98.9％、98.9％和98.5％,rATG组均为98.2％ (P＞0.05);IL2Ra组移植肾存活率分别为98.5％、98.1％和97.7％,rATG组均为97.3％(P＞0.05).结论 在临床肾移植中,经rATG诱导治疗较IL2Ra有更低的急性排斥反应发生率,并且不增加发生感染的风险.     

肾移植后早期应用咪唑立宾的有效性及安全性

目的 探讨肾移植后早期应用咪唑立宾( MZR)的有效性和安全性.方法 采用前瞻性临床随机对照研究.将61例首次肾移植受者按随机数字表法分为2组:(1)MZR组:33例,应用他克莫司(Tac)+ MZR+泼尼松(Pred)预防排斥反应;(2)吗替麦考酚酯组(MMF)组:28例,应用Tac+ MMF+ Pred预防排斥反应.MZR的用法为:体重＜50 kg者为150mg/d,早餐后口服;体重≥50kg者为200 mg/d,分早、晚2次口服.MMF、Tac和Pred按常规剂量服用.2组受者均于术前2h和术后4d接受巴利昔单抗(20mg/d)诱导治疗.观察并比较2组受者术后6个月内的急性排斥反应(AR)发生率、移植肾存活率以及高尿酸血症、骨髓抑制、巨细胞病毒感染、胃肠道反应等的发生率.结果 术后6个月内,MZR组AR发生率为15.2％,MMF组AR发生率为10.7％ (P＞0.05);MZR组移植肾存活率为97.0％,MMF组移植肾存活率为89.3％(P＞0.05).MZR组和MMF组间高尿酸血症、骨髓抑制、胃肠道反应和肺部感染的发生率的差异无统计学意义(P＞0.05).其中,MZR组未发生巨细胞病毒感染,而MMF组则发生4例(36.4％),差异有统计学意义(P＜0.05).结论 在严密监测下,MZR可应用于肾移植术后早期抗排斥反应治疗.     

肾移植2508例次临床总结

目的总结肾移植的临床经验,探讨影响移植术后人／肾存活的因素,提高长期存活率。方法回顾性总结1979年1月～2008年6月2508例次肾脏移植资料,分析患者术前状况、组织配型、群体反应性抗体（PRA）、供肾的切取、灌注、热冷缺血时间、植肾技术、术后并发症的发生、不同免疫抑制剂方案、再次移植等因素对移植效果及人／肾存活率的影响。结果①移植效果：总体人／肾存活率81．4％／76．3％;近10年来,1、5、10年人／肾存活率（%）分别为：96．5／93．2、88．6／81．6和74．7／71．3;186例活体亲属供者随访均健康存活,受者1年人／肾健康存活率98．5％／95．5％;②排斥反应：超级排斥反应发生率0．7％,急性排斥反应（AR）发生率13．7％,近十年来急性排斥反应（AR）发生率7．4％;③术后并发症：发生各种感染787例,急性肾小管坏死（ATN）275例,药物毒副作用590例,肾动脉及肾破裂19例;晚期输尿管梗阻39例,恶性肿瘤28例;④死亡原因：前三位的分别是感染占47．3％,心脑血管并发症占34．8％,肝功能衰竭占10．9％。结论充分的术前准备、良好的HLA配型、加强PRA检测是提高存活率的基础;高质量的供肾和娴熟的移植技术是肾移植成功的重要保证;科学、合理、个体化的应用免疫抑制剂是移植后治疗的重点,环孢素A（CsA）或他克莫司（FK506）、霉酚酸酯（MMF）、泼尼松（Pred）三联是目前首选的免疫抑制治疗方案。加强感染的早期监测、预防性治疗是术后早期治疗的另一关键．加强患者的随访,提高患者的依从性,对指导肾移植受者长期存活具有重要价值。     

2300例次肾移植的临床分析

目的：对1972－2000年10月间2300例次肾移植情况进行临床分析,方法：统计肾移植后受者1、3、5年的人、肾存活率;肾移植主要并发症及其处理原则;影响受者再次移植存活率的因素;HLA－A－抗原／基因配型及群体反应抗体（PRA）检测情况。结果（1）自1985年使用环孢素A（CsA)后1年人、肾存活率（人、肾均存活）为87．33％,3年为80．17％,5年为67．04％。（2）50岁以上肾移植患者353例,1年移植肾存活率83．44％（252／302）,1年人存活率85．43％（258／302）。（3）肾移植术后患者心脑血管系统疾病占死亡原因的50．7％,感染占死亡率的13．5％,（4）恶性肿瘤的发病率为1．46％（23／1580）。（5）良好的HLA供－受者配型型可减少术后急性排斥反应的发生率,利用于移植肾的长期存率。结论良好的组织配型,肾移植术后免疫抑制药物的合理应用,对移植术后并发症的预防和及时治疗是提高肾移植术后 人／肾存活率的重要因素。     

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.