臭氧氧化预处理在肾缺血再灌注损伤中对内皮型一氧化氮合酶表达的影响

目的 观察臭氧氧化预处理对大鼠急性肾缺血再灌注损伤的保护作用及其对内皮型一氧化氮合酶（eNOS）表达的影响.方法 38只8周龄雄性Wistar大鼠按随机数字表法随机分为4组.（1）假手术组（n＝8）：仅切除右肾;（2）缺血再灌注组（n＝10）：切除右肾、游离左肾后夹闭左肾动、静脉45 min再开通;（3）臭氧氧化预处理组（n＝10）：与缺血再灌注组建模方法一致,但在建模前15 d起每天1次经直肠灌注法吹入氧气和臭氧的混合气体5~5.5 mL;（4）氧气预处理组（n＝10）：与臭氧氧化预处理组建模方法一致,但经直肠仅吹入氧气（13 mg/kg）.建模后24 h检测各组大鼠血清肌酐、血尿素氮和血清一氧化氮浓度;48 h后采用免疫组织化学法和逆转录PCR法检测各组大鼠肾组织eNOS表达;蛋白质印迹法检测肾组织胞浆eNOS含量.结果 建模后24 h,缺血再灌注组大鼠血清肌酐为（117±20）μmol/L,血尿素氮为（32.8±7.6）mmol/L,血清一氧化氮为（58±12）μmol/L,均高于假手术组,差异有统计学意义（均P〈0.05）.臭氧氧化预处理组血清肌酐为（63±16）μmol/L,血尿素氮为（17.4±5.2）mmol/L,低于缺血再灌注组和氧气预处理组,差异有统计学意义（均P〈0.05）;血清一氧化氮为（84±14）μmol/L,均高于缺血再灌注组和氧气预处理组,差异有统计学意义（均P〈0.05）.臭氧氧化预处理组肾组织学Paller评分（41±6）低于缺血再灌注组（62±9）,eNOS灰度值（163±15）高于缺血再灌注组（126±18）,差异有统计学意义（均P〈0.05）.假手术组大鼠肾组织内有微量eNOS mRNA表达,缺血再灌注组、臭氧氧化预处理组和氧气预处理组eNOS mRNA表达增强,均高于假手术组（均P〈0.05）,臭氧氧化预处理组eNOS mRNA表达高于缺血再灌注组和氧气预处理组（均P〈0.05）.假手术组无明显eNOS蛋白表达,缺血再灌注组、臭氧氧化预处理组和氧气预处理组eNOS蛋白表达增强,均高于假手术组（均P〈0.05）,臭氧氧化预处理组eNOS蛋白表达高于缺血再灌注组和氧气预处理组（均P〈0.05）.结论 臭氧氧化预处理对大鼠肾缺血再灌注损伤有保护作用,作用机制可能与其诱导eNOS合成增多、一氧化氮产生增多有关.     

臭氧氧化预处理对大鼠肾缺血再灌注损伤的热休克蛋白表达的影响

目的 探讨臭氧氧化预处理通过诱导热休克蛋白70(HSP70)的合成,保护大鼠肾脏缺血再灌注损伤的作用与机制.方法 建立原位大鼠单侧肾缺血再灌注动物模型,I/R前15 d经直肠吹入氧气和臭氧的混合气体5.0～5.5 ml(臭氧浓度50 mg/L,1 mg/kg体蕈,每日 1次).全自动生化分析仪检测尿素氮(BUN)、肌酐(Cr),比色法测定血清的脂质过氧化产物丙二醛(MDA)、超氧化物歧化酶(SOD).Western blot检测HSP70蛋白的含量;逆转录聚合酶链反应(RT-PCR)方法检测HSP70的表达.结果 肾缺血再灌注24 h后,血清中BUN、Cr、MDA明显增高,肾组织内HSPT0表达明显增强(P<0.05),经臭氧氧化预处理后,血清中的BUN、Cr、MDA均降低,SOD升高;HSP70表达升高更加明显(P<0.05).结论 臭氧氧化预处理可以诱导大鼠肾缺血再灌注组织中HSP70表达,减轻大鼠肾脏缺血再灌注损伤.     

臭氧氧化预处理对大鼠肾缺血再灌注损伤的热休克蛋白表达的影响

目的 探讨臭氧氧化预处理通过诱导热休克蛋白70(HSP70)的合成,保护大鼠肾脏缺血再灌注损伤的作用与机制.方法 建立原位大鼠单侧肾缺血再灌注动物模型,I/R前15 d经直肠吹人氧气和臭氧的混合气体5.0～5.5 ml(臭氧浓度50 mg/L,1 mg/kg体重,每日1次).全自动生化分析仪检测尿素氮(BUN)、肌酐(Cr),比色法测定血清的脂质过氧化产物丙二醛(MDA)、超氧化物歧化酶(SOD).Western blot检测HSP70蛋白的含量;逆转录-聚合酶链反应(RT-PCR)方法检测HSPT0的表达.结果 肾缺血再灌注24 h后,血清中BUN、Cr、MDA明显增高,肾组织内HSP70表达明显增强(P＜0.05),经臭氧氧化预处理后,血清中的BUN、Cr、MDA均降低,SOD升高;HSP70表达升高更加明显(P＜0.05).结论 臭氧氧化预处理可以诱导大鼠肾缺血再灌注组织中HSP70表达,减轻大鼠肾脏缺血再灌注损伤.     

丙泊酚对大鼠急性肾缺血再灌注损伤的影响

目的 探讨丙泊酚预处理对急性肾缺血再灌注损伤(acute renal ischemia reperfusion injury ,ARIRI)的保护作用及其机制.方法 采用完全随机研究设计(randomized controlled trial,RCT),健康近交系清洁级的雄性SD大鼠63只,随机分为3组:假手术组(A组)、缺血再灌注组(B组)、丙泊酚预处理组(C组),每组21只SD大鼠.采用切除右侧肾,用无损伤微动脉夹夹闭左侧肾蒂60分钟后解除阻断,建立大鼠急性肾缺血再灌注损伤模型.用24号套管针股静脉穿刺置管,实验过程中各组使用微量注射泵注入不同注射液.分别于手术前15分钟、再灌注后2小时、24小时留取血和肾组织标本同时处死大鼠,检测血清尿素氮(BUN)、肌酐(Cr)、超氧化物歧化酶(SOD)、丙二醛(MDA)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)及观察这三个时点肾组织的病理学改变.结果 丙泊酚预处理组各个时点的肾组织病理学变化均轻于缺血再灌注组.缺血再灌注组中血清BUN、Cr、MDA和TNF-α水平增加均高于丙泊酚预处理组(p＜0.05),丙泊酚预处理组血清SOD、IL-6水平均高于缺血再灌注组(p＜0.05).结论 丙泊酚预处理组血清BUN、Cr、MDA、TNF-α、SOD、IL-6水平与缺血再灌注组均有统计学差异.结果 表明丙泊酚能减少氧自由基释放,抑制和减少炎症反应,在急性肾缺血再灌注损伤能起到保护肾脏的作用.     

缺血预处理联合后处理对大鼠肾缺血再灌注损伤的影响

目的 评价缺血预处理联合后处理对大鼠肾缺血再灌注损伤的影响.方法 健康雄性SD大鼠30只,体重250～280 g,随机分为5组(n=6):假手术组(S组)、缺血再灌注组(I/R组)、缺血预处理组(IP组)、缺血后处理组(IPo组)和缺血预处理联合后处理组(IP+IPo组).S组仅开腹,游离双侧肾脏,分离双侧肾蒂但不夹闭.采用夹闭双侧肾蒂45 min、再灌注6 h的方法 制备肾缺血再灌注模型.IP组夹闭双侧肾蒂5 min,再灌注5 min,反复3次,余操作同I/R组;IPo组夹闭双侧肾蒂45 min后,再灌注10 8,缺血10 s,反复3次,再灌注6 h.于再灌注6 h时,经心脏抽血后迅速处死大鼠取肾,测定血清肌酐(Cr)和尿素氮(BUN)的浓度;采用硫代巴比妥酸法测定肾组织丙二醛(MDA)含量,采用黄嘌呤氧化酶法测定肾组织超氧化物歧化酶(SOD)活性;光镜下观察肾组织病理学结果 ;TUNEL法检测肾组织凋亡细胞,计算凋亡指数(AJ).结果 与S组比较,其余各组血清Cr和BUN的浓度升高,肾组织SOD活性降低,MDA含量和AI升高(P<0.05);与I/R组比较,IP组、IPo组和IP+IPo组血清Cr和BUN的浓度降低,肾组织SOD活性升高,MDA含量和AJ降低(P<0.05),肾损伤减轻;与IP组和IPo组比较,IP+IPo组肾组织SOD活性升高,AI降低(P<0.05),肾损伤减轻.结论 缺血预处理联合后处理可减轻大鼠肾缺血再灌注损伤,较单独应用时效果好.     

中介素减轻大鼠肾脏缺血再灌注损伤

目的 探讨中介素(IMD)对大鼠肾脏缺血再灌注损伤(IRI)的影响,及其过程中一氧化氮合酶(NOS)的作用和机制.方法 将健康雄性Wistar大鼠分为4组:假手术组,行右肾切除术,1周后单纯分离左侧肾蒂及肾动脉,而不夹闭肾动脉；肾脏缺血再灌注(IR)组,行右肾切除术,1周后行左肾缺血再灌注手术；IMD基因转染组,右肾切除后左肾行超声微泡介导的IMD-pCDNA3.1(+)质粒转染术,饲养1周,再行左肾缺血再灌注手术；空质粒转染组,右肾切除后左肾行超声微泡介导的pCDNA3.1(+)质粒转染术,饲养1周,再行左肾缺血再灌注手术.大鼠于缺血再灌注术后24 h处死,用免疫组织化学方法检测肾组织IMD表达,取肾组织进行病理学观察,取血清测定尿素氮(BUN)和肌酐(Cr)浓度,检测肾组织中内皮型NOS(eNOS)、诱导型NOS(iNOS)以及神经型NOS(nNOS) mRNA及其蛋白的表达.结果 假手术组大鼠肾组织中IMD位于肾小管及间质细胞胞浆内,其表达灰度值为66±35;肾脏IR组大鼠肾小管上皮细胞和间质中IMD表达灰度值为176±48,高于假手术组(P＜0.01)；IMD基因转染组肾组织中IMD表达灰度值为262±68,高于肾脏IR组(P＜0.01)；空质粒转染组IMD表达灰度值为180±51,和肾脏IR组间表达的差异无统计学意义(P＞0.05).与肾脏IR组相比较,IMD基因转染组大鼠肾脏组织病理损伤程度较轻,血清BUN和Cr较低(P＜0.05),eNOS mRNA及eNOS表达升高(P＜0.05),iNOS mRNA及iNOS表达降低(P＜0.05),而两组间nNOSmRNA及nNOS表达的差异无统计学意义(P＞0.05).结论 中介素可能通过促进eNOS表达、抑制iNOS表达从而减轻大鼠肾脏IRI.     

缺血后处理减轻犬肾缺血再灌注损伤的作用

目的 探讨缺血后处理减轻犬肾缺血再灌注损伤的作用及其相关机制.方法 随机将犬分为假手术组、缺血再灌注组和缺血后处理组,每组5只.假手术组:犬麻醉后,取其腹正中切口进入腹腔,游离双侧肾脏,切除右肾后,关腹.缺血再灌注组:手术操作与假手术组相同,仅在切除右肾和游离左肾之后,将左肾动、静脉夹闭60 min,然后开放血管.缺血后处理组:手术操作与缺血再灌注组相同,仅在肾动、静脉被夹闭60 min后,以再灌注(开放血管)30 s、夹闭血管30 s为1个循环,共进行6次循环,然后完全放开血管.分别于术后24、48及72 h采集犬静脉血2 ml,使用全自动生化分析仪测定各组犬血清肌酐(Cr)和尿素氮(BIJN)水平;术后第3天取犬肾组织,采用硫代巴比妥酸法测定丙二醛(MDA)含量,采用黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活性,采用化学比色法测定髓过氧化物酶(MPO)活性,并观察犬肾组织的病理改变和细胞凋亡情况.结果 术后各时间点,缺血再灌注组、缺血后处理组和假手术组犬的血清Cr和BUN水平均依次降低,3组间比较,差异均有统计学意义(P<0.05).术后第3天,缺血再灌注组、缺血后处理组和假手术组犬肾组织中SOD活性依次升高,而MDA含量和MPO活性均依次降低,3组间比较,差异均有统计学意义(P<0.05).假手术组肾小球和肾小管结构正常,未见明显病理改变;缺血再灌注组肾间质水肿,大量炎症细胞浸润,肾小管上皮细胞刷状缘消失,大量上皮细胞坏死、脱落,管腔扩张,其中可见大量管型;缺血后处理组可见肾间质轻度水肿,肾小管上皮细胞扁平,部分刷状缘消失、坏死,偶见管型,管周血管有少量淤血.假手术组、缺血再灌注组、缺血后处理组犬肾的细胞凋亡指数分别为2.7±1.3、28.4±6.2和15.4±4.1,3组间比较,差异均有统计学意义(P<0.05).结论 缺血后处理能减轻犬肾缺血再灌注损伤,其机制可能与缺血后处理减少氧自由基的产生、抑制细胞凋亡及减少炎症细胞浸润有关.     

臭氧氧化预处理减轻大鼠脊髓缺血再灌注损伤

目的探讨臭氧氧化预处理对大鼠脊髓缺血再灌注损伤的作用及可能机制。方法将36只健康成年雄性SD大鼠随机分为假手术组、模型组和臭氧预处理组,每组12只。模型组和臭氧预处理组采用夹闭右肾动脉上腹主动脉的方法构建大鼠脊髓缺血再灌注损伤模型,臭氧预处理大鼠于建模前7 d开始以1 mg/(kg·d)腹腔注射臭氧(50 mg/L)-氧气混合气体至建模。分别于恢复灌流后6、12、24和48 h时,对各组大鼠后肢神经运动功能进行评分。末次评分后取脊髓标本,行HE染色观察组织病理学变化,行2,3,5-氯化三苯基四氮唑(TTC)染色检测缺血面积,用试剂盒检测丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)水平。结果与假手术组相比,模型组和臭氧预处理组大鼠恢复灌流后6、12、24、48 h神经运动功能评分均降低,差异均有统计学意义(P 0.05);与模型组相比,臭氧预处理组大鼠恢复灌流后6、12、24、48 h神经运动功能评分升高,差异有统计学意义(P 0.05)。与假手术组相比,模型组和臭氧预处理组大鼠脊髓组织缺血面积增大,差异均有统计学意义(P 0.05);与模型组相比,臭氧预处理组大鼠脊髓缺血面积减小,差异有统计学意义(P 0.05)。与假手术组相比,模型组和臭氧预处理组大鼠脊髓组织中MDA水平升高,而SOD和GSH-Px水平降低,差异均有统计学意义(P 0.05);与模型组相比,臭氧预处理组大鼠脊髓组织中MDA水平降低,而SOD和GSH-Px水平升高,差异均有统计学意义(P 0.05)。结论臭氧预处理可有效减轻大鼠脊髓缺血再灌注损伤,其机制可能与抑制脊髓组织氧化应激反应有关。     

缺血预处理对大鼠急性缺血-再灌注肾细胞凋亡的影响

目的:探讨缺血预处理对急性肾缺血-再灌注细胞凋亡的影响。方法:采用8 min缺血加5 min再灌注预处理在体肾缺血-再灌注模型(I45 min I-R 6h),将实验动物随机分为正常(A组)、假手术(S组)、单纯缺血(B组)、缺血再灌注(C组)、预处理(D组)五组,采用透射电镜、流式细胞仪检测肾细胞凋亡和细胞增殖周期,利用光学显微镜进行组织学观察,同时测定血清中尿素氮(BUN)、肌酐(Cr)及MDA含量。结果:与A、S组相比,C组细胞凋亡率显著增高(P<0.01);与C组相比,D组细胞凋亡率和细胞增殖指数均降低(P<0.01),G0/G1时段增加(P<0.01),肾组织损伤病理评分显著降低(P<0.05),同时肾超微结构破坏较轻。结论:缺血预处理对急性肾缺血-再灌注有保护作用,可以减轻急性肾缺血-再灌注引起的细胞凋亡,其作用机制可能与调节细胞增殖周期有关。     

缺血后处理对肾缺血再灌注损伤的抑制作用及对细胞凋亡的影响

目的 观察缺血后处理对大鼠急性.肾缺血再灌注损伤的抑制作用及其对细胞凋亡的影响.方法 建立原位大鼠单侧肾缺血再灌注动物模型,摘除右肾后对左肾行缺血后处理,即10 s再灌注,10 s缺血,6次循环后再灌注24 h.全自动生化分析仪检测血尿素氮(BUN)和肌酐(Cr)含量,比色法测定血浆中脂质过氧化产物丙二醛(MDA)和超氧化物歧化酶(SOD)含量,免疫组织化学法观察肾组织中细胞色素C的表达,流式细胞术检测细胞凋亡率,免疫印迹法(Western blot)检测胞浆中细胞色素C的含量.结果 肾缺血再灌注24 h后,血中BUN、Cr和MDA明显增高,肾细胞凋亡率明显增加.移植肾经缺血后处理,血中BUN、Cr和MDA含量均降低,SOD含量升高,细胞色素C释放减少,肾细胞凋亡率明显降低.结论 缺血后处理可以减轻移植肾脂质过氧化反应,减少肾细胞凋亡率,减轻肾缺血再灌注损伤.     

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.