不同置换量的连续性血液滤过治疗多器官功能障碍综合征的疗效分析

目的观察不同置换量的连续性静脉-静脉血液滤过(continuous veno-venous hemo-filtration,CVVH)治疗多器官功能障碍综合征(multiple organ dysfunction syndrome,MODS)的疗效及预后。方法选择2010年8月至2013年6月在百色市人民医院 ICU 接受 CVVH 治疗的 MODS患者60例,按随机数字表法分为低剂量组(CVVH 组)和高剂量组(HVHF组)。CVVH 组30例,前稀释方式置换液流量2 L/h[平均(34.70±5.38)ml·kg-1·h-1];HVHF组30例,前稀释方式置换液流量4~5 L/h[平均(68.0±6.49)ml·kg-1·h-1],对比分析2组CVVH 治疗前和治疗24 h后的生命体征、APACHEⅡ评分、APACHEⅡ死亡风险系数、SOFA 评分、平均动脉压(MAP)、氧合指数(PaO2/FiO2)、血尿素氮(BUN)、血肌酐(SCr)、C 反应蛋白(CRP)、白介素-2(IL-2)、白介素-6(IL-6)、白介素-8(IL-8)、肿瘤坏死因子(TNF-α)、γ型干扰素(IFN-γ)等指标,并统计2组患者28日病死率。结果(1)经过治疗后,CVVH组的APACHEⅡ评分、APACHEⅡ死亡风险系数、SOFA评分、PaO2/FiO2、CRP、IL-2、IL-6、IL-8、TNF-α、IFN-γ改善,但无统计学意义(P>0.05),MAP、pH、BUN、SCr改善有统计学意义(P<0.05);(2)经过治疗后,HVHF组的 APACHEⅡ评分、APACHEⅡ死亡风险系数、SOFA评分、PaO2/FiO2、MAP、BUN、SCr、CRP、IL-2、IL-6、IL-8、TNF-α、IFN-γ改善均有统计学意义(P<0.05);(3)CVVH 组的28日的病死率为46.67%,HVHF组为36.67%,HVHF低于 CVVH组,但2组差异无显著性(P<0.05)。结论2组均能改善 MODS 患者病情,降低病死率,但高剂量的CVVH 治疗更有利于缓解 MODS病情,其机制可能与清除炎症介质有关。     

经下腔静脉逆灌注对肝移植大鼠早期肾功能的影响

目的 观察经下腔静脉逆灌注对自体原位肝移植大鼠早期肾功能的影响.方法 将70只自体原位肝移植SD大鼠按肝脏的灌注方式不同随机分为经下腔静脉逆灌注组与经门静脉正灌注组,各组35只.各组再随机分成术前对照组、术后6、12、24、48h5个亚组,各亚组7只.经下腔静脉逆灌注组:先开放下腔静脉,再同时开放门静脉与肝动脉；经门静脉正灌注组:先开放门静脉,再依次开放下腔静脉、肝动脉.分别检测两组中各亚组的血清肌酐( Scr)、尿素氮(BUN)、肾损伤分子(KIM)-1及肿瘤坏死因子(TNF)-α水平；取各亚组左肾组织行光镜检查,观察肾组织KIM-1免疫组织化学,计算KIM-1阳性细胞计数.结果 两组术前Scr、BUN、KIM-1及TNF-α比较差异无统计学意义(P＞0.05).与正灌注组比较,术后6、12及24 h逆灌注组的Scr、BUN及TNF-α水平显著降低[术后6h,Scr:(57.4±14.2) mol/L比(48.0±14.0) mol/L,BUN:(14.1±1.5) mmol/L比(8.0±1.1)mmol/L,TNF-α:( 330.1±11.6) ng/L比(294.5±16.2) ng/L;术后12 h,Scr:(125.0±40.4) mol/L比(105.4 ±40.6) mol/L,BUN:(32.2±2.8)mmol/L比(19.6±2.1)mmol/L;TNF-α:(503.6 ±46.6)ng/L比(261.8±9.1)ng/L;术后24h,Scr:(57.8±12.6)mol/L比(45.4±11.8) mol/L,BUN:(16.4±3.0) mmol/L比(13.6±3.2) mmol/L,TNF-α:(408.2±20.9) ng/L比(226.0±21.1) ng/L]；术后48 h差异无统计学意义(P＞0.05)；术后6、12、24、48 h逆灌注组血清KIM-1水平均显著降低[术后6h,(107.8±2.1)ng/L比(87.3±1.3)ng/L;术后12 h,(107.8±2.1)ng/L比(87.3±1.3) ng/L;术后24 h,(101.7±1.8)比(81.9±1.6) ng/L;术后48 h:(99.7 ±2.6) ng/L比(77.5±0.6)ng/L;P ＜0.05],肾组织中KIM-1阳性细胞计数及免疫组织化学评分显著降低(术后6h,40±3比26 ±2;术后12h,45 ±3比31 ±3;术后24 h,56 ±4比35±4；术后48 h:60±3比32±2;P＜0.05).结论 经下腔静脉逆灌注可减轻SD大鼠自体原位肝移植术后早期肾功能的损害.     

不同剂量血液滤过对内毒素休克猪生存时间和细胞因子水平的影响

目的 探讨不同剂量连续性血液滤过（CVVH）对细胞因子的清除作用以及对血浆细胞因子水平的影响。 方法 采用静脉注射内毒素（E.coli O111: B4,15.7 μg/kg）的方法诱导内毒素休克猪模型。将内毒素休克猪按随机数字表法分为对照组(n=6)、 CVVH组 (n=6,前稀释法,等于后稀释法的45 ml·kg-1·h-1）和高容量血液滤过（HVHF）组 (n=6,前稀释法,等于后稀释法的70 ml·kg-1·h-1）。于造模前（基线）、成模时（T0）,成模后1 h（T1）、6 h（T6）、12 h（T12）、24 h（T24）分别测定血浆肿瘤坏死因子α（TNF-α）、白细胞介素（IL）6、IL-10和IL-18水平。 结果 对照组动物平均生存时间为（15.4±5.2） h;CVVH 组为(21.4±7.1) h;HVHF组为（22.4±6.7） h,CVVH组和HVHF组的生存时间显著高于对照组（均P < 0.05）。3组动物的心率（HR）、平均动脉压（MAP）、中心静脉压（CVP）和心排出量（CO）之间差异无统计学意义（P > 0.05）。内毒素休克猪成模后出现BUN和Scr的进行性升高,两治疗组的BUN和Scr水平显著低于对照组（P < 0.05）,但两者之间差异无统计学意义（P > 0.05）。对照组TNF-α和IL-6水平在T1时达高峰,IL-10水平在T0时最高,随后不断下降。IL-18水平在成模后上升,后无明显变化。CVVH组血浆IL-10（T6、T12、T24）水平低于对照组（P < 0.05）。HVHF组TNF-α（T6）和IL-10（T6、T12、T24）水平低于对照组和CVVH组（P < 0.05）,3组的IL-6和IL-18水平差异无统计学意义,IL-6（T6、T12）水平和动物生存时间呈负相关（P < 0.05）。 结论 CVVH和HVHF治疗均能显著延长内毒素休克猪的生存时间。CVVH能有效清除IL-10;HVHF治疗能清除TNF-α和IL-10;但CVVH和HVHF对IL-6和IL-18水平无明显影响;CVVH和HVHF均能有效清除BUN和Scr。IL-6水平是预测内毒素休克预后的独立指标。     

早期血滤对重症急性胰腺炎家猪血浆细胞因子水平的影响

目的　探讨早期血液滤过对重症急性胰腺炎 (SAP)家猪促抗炎细胞因子血浆水平的影响。方法　采用胰管逆行灌注人工胆汁的方法复制家猪SAP模型 ,随机分为胰腺炎血滤治疗组(HF组 ,n =8)和胰腺炎非血滤治疗组 (NHF组 ,n =8)。HF组使用高容量、零平衡血滤。用酶联免疫吸附试验检测两组动物建模前后血浆肿瘤坏死因子 (TNF) α、白细胞介素 (IL) 1β、IL 10的水平。结果　与NHF组相比 ,血滤治疗后HF组家猪TNF α、IL 1β的血浆水平较低 [血滤停止前( 618± 2 76)ng/L较 ( 13 75± 3 3 4)ng/L ;( 4 45± 14 1)ng/L较 ( 965± 2 65 )ng/L ,P <0 .0 1] ,IL 10与TNF α的比值较高 [血滤停止前 ( 0 .3 5 4± 0 .114 )较 ( 0 .12 5± 0 .0 3 2 ) ,P <0 .0 1]。结论　早期血滤能降低SAP家猪促炎细胞因子TNF α,IL 1β的血浆水平 ,升高IL 10 /TNF α的比值 ,使促抗炎细胞因子失衡得到部分纠正。     

早期血液滤过对重症急性胰腺炎家猪TNF-α及IL-1β水平的影响

目的　探讨早期血液滤过对重症急性胰腺炎 (SAP)家猪血浆促炎细胞因子TNF α和IL 1β水平和组织转录水平的影响。方法　采用胰管逆行灌注人工胆汁的方法复制家猪SAP模型 ,按拆信封法分为胰腺炎血滤治疗组 (HF组 )和胰腺炎非血滤治疗组 (NHF组 )。采用ELISA法检测两组动物建模前、后TNF α和IL 1β的血浆水平。用半定量逆转录聚合酶链式反应检测这两种细胞因子在胰、肝、肺组织中的转录水平。结果　建模后 1h、2h及 4h ,NHF组血浆TNF α及IL 1β水平逐渐升高 ,至 6h分别为 ( 1375± 334)pg/ml及 ( 96 5± 2 6 5 )pg/ml,明显高于同期HF组的 ( 6 18± 2 76 )pg/ml及 ( 4 45± 14 1)pg/ml(P<0 .0 1)。建模后 6h ,NHF组胰、肝、肺组织中TNF αmRNA的转录水平分别为 85 .7± 17.4、78.1± 10 .2和 82 .4± 10 .5 ,均高于HF组的 5 7.8± 8.9、4 8.0± 8.1和 4 6 .2± 9.6 ,P<0 .0 1;而IL 1βmRNA的转录水平NHF组为 82 .2± 15 .7、6 0 .0± 10 .6和 5 8.1±9.3,均高于HF组的 5 5 .9± 9.0、4 0 .6± 9.2和35 .7± 9.8,P<0 .0 1。结论　早期血滤能降低SAP家猪血浆TNF α和IL 1β的水平和转录水平     

断流分流联合手术前后血浆IL-6,IL-8和TNF-α水平的变化及其意义

目的　探讨门静脉高压症行贲门周围血管离断并脾 -肾静脉分流联合手术前后血浆白细胞介素 -6(IL 6) ,白细胞介素 -8(IL 8)和肿瘤坏死因子 -α(TNF α)水平变化的意义。方法　检测联合手术组患者术前 1d和术后 7d血浆IL 6,IL 8和TNF α含量 ,并与对照组比较。结果　联合手术组术前IL 6,IL 8和TNF α水平分别为 ( 2 3 0 .4± 10 .3 )ng/L ,( 2 0 1.5± 7.8)ng/L及 ( 2 61.5± 2 8.3 )ng/L ,明显高于对照组 (P <0 .0 1) ;联合手术后 7d ,IL 6,IL 8和TNF α水平分别为 ( 13 5 .8± 11.4)ng/L ,( 10 8.2± 8.7)ng/L及 ( 2 11.8± 3 6.5 )ng/L ,与术前比均有明显降低 ,但仍高于对照组 ( P <0 .0 1)。结论　IL 6,IL 8和TNF α的活性在肝硬化门静脉高压症的形成过程中起着重要作用 ;联合手术降低门静脉压力 ,血浆IL 6,IL 8和TNF α水平显著下降 ,表明有利于肝功能的恢复     

体外膜肺联合血液滤过治疗肺肾衰竭的实验研究

目的 观察体外膜氧合器（ECMO）联合高容量血液滤过（HVHF）对急性呼吸窘迫综合征（ARDS）、急性肾功能衰竭（ARF）的治疗作用。 方法 采用实验犬32只，随机分为A、B、C、D 4组。静脉注射油酸复制ARDS模型及双侧输尿管结扎复制急性肾功能衰竭模型。A组用ARDS呼吸机治疗；B组ARDS用ECMO治疗；C组ARDS＋ARF用HVHF治疗；D组ARDS＋ARF用ECMO联合HVHF治疗。监测血气、血流动力学以及血生化等指标。 结果 治疗后B组氧分压（PaO2）逐步上升，在治疗4 h后高于A组[（95.58±8.14） 比（82.79±12.37） mm Hg，P < 0.05]； C组PaO2治疗中较成模时无明显改善；D组PaO2呈逐渐上升趋势，在各时间点均高于C组（P < 0.05）。各组血流动力学指标在治疗中保持稳定。C、D组HVHF治疗后Scr、BUN明显降低[C组：Scr (320.89±65.42) 比(655.04±181.22) μmol/L，BUN (20.42±6.65) 比（41.53±10.59）mmol/L；D组：Scr (334.15±45.97)比（697.48±101.66） μmol/L，BUN (19.12±6.39) 比（39.10±11.60） mmol/L，P均< 0.01]。 结论 ECMO可以有效地改善ARDS低氧血症，联合HVHF可以提供肺肾功能联合支持。     

烧伤患者应用亚胺培南/西司他丁钠盐或头孢哌酮后部分炎症介质水平的改变

目的　观察应用亚胺培南 /西司他丁钠盐 (IPM)或头孢哌酮 (CPZ)治疗烧伤感染患者后其部分血浆炎症介质水平的变化及差异。　方法　选择 13例革兰阴性杆菌感染的烧伤患者 ,其中7例应用IPM(IPM组 ) ,6例应用CPZ(CPZ组 )。于用药前及用药后 2、12、2 4、4 8、72h抽取静脉血 ,检测血浆内毒素 /脂多糖 (LPS)、肿瘤坏死因子α(TNF α)和白细胞介素 6 (IL 6)水平的变化 ,并进行相关性分析。结果　用药后 2h两组患者血浆LPS水平升高 ,其中CPZ组较用药前升高了 (13.95±10 .2 9)pg/ml( P <0.0 5),升高幅度大于IPM组 ,随后逐渐降低。CPZ组用药后 2hTNF α水平为(0 .86± 0 .16 )ng/ml,明显高于用药前 [(0 .38± 0 .15 )ng/ml]及IPM组 [(0 .4 7± 0 .13)ng/ml](P <0.0 1)。两组患者用药后各时相点血浆IL 6水平与用药前比较及组间比较 ,差异均无显著性意义 (P >0.0 5)。两组患者TNF α水平与LPS、IL 6水平呈显著正相关 (P <0.0 0 1～ 0.0 1)。结论　应用不同种类抗生素治疗革兰阴性杆菌感染的烧伤患者时 ,可诱导细菌释放LPS、TNF α,其释放量存在一定差异。TNF α的产生与LPS、IL 6的释放存在相关性。     

高渗盐水对重症急性胰腺炎大鼠全身性炎症反应的影响

目的研究高渗盐水治疗重症急性胰腺炎(severeacutepancreatitis,SAP)时大鼠炎性细胞因子、胰腺、肺组织病理损害的变化及其机制。方法Wistar大鼠48只,均分成对照组、SAP模型组、等渗盐水组、高渗盐水组,采用过量L精氨酸诱导大鼠SAP模型,等渗盐水组、高渗盐水组于24h、48h分别经静脉输入2mlkg的09%NaCl、75%NaCl,在48h、72h取血测肿瘤坏死因子α(TNFα)、白细胞介素6(IL6)、IL10水平,于72h检查大鼠胰腺、肺组织病理变化。结果高渗盐水组胰腺和肺组织病理学改变明显轻于等渗盐水组;等渗盐水组血清TNFα、IL6、IL10水平在48h和72h分别为[(311±22)、(43±5)、(22±4)]pgml和[(403±29)、(66±7)、(28±6)]pgml。高渗盐水组分别为[(278±20)、(38±6)、(26±7)]pgml和[(329±28)、(42±6)、(44±5)]pgml;高渗盐水组血清TNFα、IL6值明显低于等渗盐水组,IL10值明显高于等渗盐水组,尤其在72h两组之间差异有显著意义。结论高渗盐水治疗大鼠SAP能使血清TNFα、IL6水平显著降低和IL10水平显著增高,减轻胰腺、肺等组织损伤。     

连续性肾替代治疗对多脏器功能不全综合征患者炎性介质清除及内皮细胞功能的影响

目的 研究连续性肾替代治疗（CRRT）对多脏器功能不全综合征（MODS）患者外周血炎性介质清除及内皮细胞功能的影响。 方法 选取我院30例MODS患者,行CRRT治疗,每次治疗时间不短于24 h,分别于治疗开始时（0 h）和治疗后3、6、12、24 h取血检测肿瘤坏死因子α（TNF-α）、白细胞介素（IL）1β、IL-4、IL-6、IL-10、E-选择素、可溶性血管细胞黏附分子（sVCAM-1）、可溶性细胞间黏附分子1（sICAM-1）和血小板活化因子乙酰水解酶（PAF-AH）。 结果 CRRT 14 d存活19例（63.3%）,28 d存活17例（56.7%）。患者电解质和酸碱平衡于治疗6 h后恢复正常。IL-1β、IL-4于治疗开始后下降,TNF-α、IL-6、IL-10在12 h时浓度达峰值[（887.88±975.46） ng/L、（132.01±118.14） ng/L、（167.01±161.66） ng/L],与治疗前[（462.24±331.03） ng/L、（106.39±90.82） ng/L、（124.51±118.39） ng/L]比较,差异有统计学意义（均P < 0.05）。但TNF-α、IL-1β、IL-4、IL-6、IL-10治疗前与治疗后24 h差异无统计学意义。治疗后,死亡组IL-6 [（145.45±14.28） ng/L]显著高于存活组[（106.03±10.86） ng/L]（P < 0.05）;死亡组IL-10[（94.93±16.09） ng/L]显著低于存活组[（143.06±12.24） ng/L]（P < 0.05）。内皮细胞E-选择素、sVCAM-1、sICAM-1于治疗开始后升高,于治疗12 h达峰值,但治疗前后差异无统计学意义。PAF-AH治疗后开始升高,治疗后水平高于治疗前。死亡组E-选择素[（287.13±42.70） μg/L比（266.26±65.26） μg/L]、sVCAM-1[（1697.25±475.24） μg/L比（1488.10±691.67） μg/L]、sICAM-1[（975.33±142.50） μg/L比 （835.40±332.41） μg/L]高于存活组;而PAF-AH低于存活组[（9.07±6.38） μg/L比 （16.32±8.95） μg/L]。 结论 CRRT能纠正MODS患者机体紊乱的内环境,并能部分纠正内皮细胞功能,但外周血炎性介质水平治疗前后差异无统计学意义。IL-6、IL-10水平可作为临床转归的预测指标。     

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 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.     

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.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.