心脏术后尿中性粒细胞明胶酶相关脂质运载蛋白和白细胞介素18与急性肾损伤的关系

目的 探讨接受体外循环心脏手术患者尿中性粒细胞明胶酶相关脂质运载蛋白（NGAL）和尿白细胞介素18（IL-18）与急性肾损伤（AKI）的关系。 方法 根据AKI的诊断标准，将33例体外循环心脏手术的患者分为AKI组及非AKI组，分别留取术前及术后不同时间点的血液和尿液标本，测定Scr、尿NGAL和IL-18水平。 结果 33例中有9例发生AKI，发生率为27.27%。AKI组Scr升高峰值出现在12～48 h内。与术前相比， AKI组术后2 h、4 h尿NGAL及IL-18水平升高，差异有统计学意义（P < 0.01）。与非AKI组比较，AKI组术后各时间点的尿NGAL水平、术后2 h及4 h的尿IL-18水平都较高，差异有统计学意义（P < 0.01）。经尿肌酐（Ucr）校正后，相应时间点的NGAL/Ucr和IL-18/Ucr差异仍有统计学意义（P < 0.01）。术后2 h尿NGAL和尿NGAL/Ucr的界定（cutoff） 值分别在250 µg/L和250 µg/mmol时；术后2 h尿IL-18和尿IL-18/Ucr的界定值分别在1800 ng/L和1800 ng/mmol时，体现出较好的敏感性和特异性。 AKI组术后12 h Scr水平与术后2 h尿NGAL水平呈正相关（r = 0.638，P < 0.05）。结论 体外循环下接受心脏手术的患者AKI发生率较高；术后2 h尿NGAL和NGAL/Ucr、术后2 h尿IL-18和尿IL-18/Ucr当达到一定界定值时，均可作为体外循环下心脏手术后AKI发生的早期诊断参考指标，其中术后2 h尿NGAL/Ucr为250 µg/mmol时更敏感。     

尿肾损伤分子-1对肺移植术后早期并发急性肾损伤患者的早期诊断

目的 探讨尿肾损伤分子-1(KIM-1)在肺移植术后急性肾损伤(AKI)中的早期诊断价值.方法 前瞻性收集本院52例肺移植手术患者在手术前后不同时相的血、尿标本,分别测定血肌酐(Scr)和尿KIM-1.根据AKI的诊断标准,将患者分为AKI组和非AKI组,观察两组Scr和尿KIM-1的动态变化.用受试者工作特征曲线(ROC)评价尿KIM-1对AKI的诊断作用.结果 52例患者中,术后发生AKI的有19例,发生率为36.5％.AKI组Scr在术后的第24h上升至基础值的1.80倍,达到AKI的诊断标准.AKI组术后4h尿KIM-1较基线值明显上升[(1.7±0.6) ng/mL比(0.5±0.3)ng/mL,P＜0.05].术后4h,尿KIM-1的ROC曲线下面积为0.837,95％的可信区间为0.729～0.946,以1.6ng/mL作为AKI的诊断界限时,敏感性和特异性分别为73.7％和75.8％.结论 尿KIM-1可较Scr更早诊断肺移植术后AKI的发生.尿KIM-1可能为肺移植术后并发AKI患者的早期诊断的标记物.     

尿中性粒细胞明胶酶相关脂质运载蛋白在成人心脏手术后急性肾损伤早期诊断中的价值

目的 探讨尿中性粒细胞明胶酶相关脂质运载蛋白（neutrophil gelatinase-associated lipocalin,NGAL）在心脏手术后急性肾损伤（AKI）早期预测和诊断中的价值。 方法 前瞻性收集我院心脏手术患者手术前后不同时相的血、尿标本,选取其中14例AKI患者,分别测定尿NGAL和Scr水平;并选择临床资料相匹配的非AKI患者15例作为对照。观察两组患者围手术期尿NGAL和Scr的动态变化,运用接受者操作特性曲线（ROC）评价尿NGAL诊断AKI的精确性。AKI定义为Scr水平较基础值增加≥50%。 结果 Scr诊断AKI的中位时间为入ICU后24 h（10 h,48 h）。AKI患者术后入ICU即刻的尿NGAL水平显著高于术前基础水平并达峰值[20.51（13.42,50.02） μg/L比3.42（1.60,9.92） μg/L,P = 0.006];也显著高于非AKI患者 [2.91（0.72,8.61） μg/L,P = 0.002]。入ICU即刻尿NGAL 的ROC曲线下面积为0.824,95%的可信区间（CI）为0.667~0.980,P = 0.003。当以10.95 μg/L作为诊断截点时,此刻的尿NGAL在AKI诊断中的敏感性和特异性分别为85.7%和80.0%。入ICU即刻的尿NGAL与入ICU 24 h的Scr（r = 0.545,P = 0.002）及eGFR（r = －0.546,P = 0.002)呈正及负相关。 结论 心脏手术后AKI患者术后入ICU即刻的尿NGAL水平显著升高,对诊断AKI具有较高的准确性,其诊断AKI的时间早于Scr。尿NGAL可作为成人心脏术后AKI的早期诊断标志物。     

尿肝型脂肪酸结合蛋白及其与尿中性粒细胞明胶酶相关脂质运载蛋白联合应用在成人心脏手术后急性肾损伤诊断中的作用

目的 探讨尿肝型脂肪酸结合蛋白( L-FABP)及其与尿中性粒细胞明胶酶相关脂质运载蛋白(NGAL)联合应用在预测成人心脏手术后急性肾损伤(AKI)的发生及严重程度中的价值,以期能为临床AKI的早期诊断提供方便可靠的方法.方法 前瞻性收集心脏手术患者术前、术后即刻及术后2h的血和尿标本,分别检测Scr、尿L-FABP和NGAL水平,比较AKI和非AKI患者术后各标志物的动态变化情况.运用受试者工作特征(ROC)曲线及曲线下面积(AUC)评估标志物单独及联合应用时诊断AKI的准确性.结果 总共109例患者中26例(23.9％)发生了AKI,其中AKIN Ⅰ、Ⅱ和Ⅲ期分别占46.2％ 、34.6％和19.2％.尿L-FABP 和NGAL水平在AKI组术后即刻及术后2h均显著高于非AKI组,其浓度变化明显早于Scr.两时间点各标志物单独预测AKI的发生及Ⅱ和Ⅲ期AKI的AUC均在0.81～0.87.用Logistic 回归方程联合术后同一时间点的尿NGAL和尿L-FABP,则术后即刻和术后2h预测术后AKI 及严重程度的精确性进一步提高( AUC=0.911～0.927).结论 尿L-FABP和尿NGAL在心脏术后AKI早期即显著升高,比Scr能更早地预测AKI的发生和严重程度,两者联合应用则可使诊断的精确性进一步提高.     

联合应用标志物在心脏手术后急性肾损伤的早期诊断

目的 探讨血清胱抑素C（CyC）、尿中性粒细胞明胶酶相关脂质运载蛋白（NGAL）、白细胞介素18（IL-18）、视黄醇结合蛋白（RBP）、N-乙酰-β-D-氨基葡萄糖苷酶（NAG）在成人心脏手术后急性肾损伤（AKI）早期预测和诊断中的价值及其联合应用的价值。 方法 前瞻性收集心脏手术患者手术前后不同时相的血尿标本,选取其中AKI患者14例,分别测定血清CyC、Scr及尿NGAL、IL-18、RBP、NAG、Cr（Ucr）水平;并选择临床资料相匹配的非AKI患者15例作为对照。观察两组患者围手术期上述5种生物学标志与Scr的动态变化。用受试者工作特征（ROC）曲线及曲线下面积（AUC）评价标志物的单独或联合应用时诊断AKI的精确性。AKI定义为Scr水平较基础值增加≥50%。 结果 29例患者平均年龄（62.9±13.7）岁,基础Scr （73.2±11.9） μmol/L。除AKI组患者术中升主动脉阻断时间较非AKI组较长外[（60.63±13.92） min比（43.00±9.20） min,P=0.047],两组其余临床指标差异均无统计学意义。AKI组患者的血尿生物学标志分别在术后早期的不同时间点显著升高。术后10 h血CyC取1.31 mg/L作为诊断截点时,其在AKI诊断中的敏感性（ST）和特异性（SP）分别为0.71和0.92,AUC=0.83（0.67~1.00）;术后0 h 尿NGAL取49.15 μg/g Ucr时,ST=0.84,SP=0.80,AUC=0.85（0.70~1.00）。术后2 h尿IL-18取285.65 ng/g Ucr时,ST=0.85,SP=0.73,AUC=0.81（0.64~0.97）。术后0 h尿RBP取2934.65 μg/g Ucr时,ST=0.75,SP=0.67,AUC=0.77（0.60~0.95）。术后4 h尿NAG取37.05 U/mg Ucr时,ST=0.86,SP=0.67,AUC=0.72（0.53~0.92）。利用Logistic回归方程,联合以上5种标志物的最佳诊断时间点,得到AUC为0.98（0.93~1.02）（P<0.01）。 结论 心脏手术后AKI患者血尿生物学标志在术后不同时间点显著升高,诊断AKI的时间早于Scr,具有较高的准确性,可作为成人心脏手术后AKI的早期诊断标志物。尿NGAL的ROC曲线下面积最大,尿RBP也显示了较好的诊断价值。联合应用生物学标志可更好地预测临床上AKI的发生。     

尿中性粒细胞明胶酶相关载脂蛋白和肝型脂肪酸结合蛋白对肝移植术后急性肾损伤的早期诊断价值

目的 探讨尿中性粒细胞明胶酶相关载脂蛋白（NGAL）和肝型脂肪酸结合蛋白（L-FABP）在肝移植术后急性肾损伤（AKI）中的早期诊断价值。 方法 前瞻性收集2007至2008年间25例肝移植患者术前、门静脉开放后2、4、6、12、24、48、72和120 h的血液和尿液标本,检测Scr和尿NGAL及L-FABP水平。根据急性肾损伤网（AKIN）标准中的Scr标准将患者分为AKI组和非AKI组。观察两组各时间点尿NGAL、尿L-FABP和Scr水平的动态变化;运用受试者工作特征曲线（ROC）评价尿NGAL和L-FABP诊断AKI的精确性。 结果 25例患者中11例发生了术后AKI,两组患者术前、术中及术后情况差异无统计学意义。术后24 h AKI组与非AKI组的Scr差异有统计学意义[(90.48±50.32) 比（59.84±14.72） μmol/L,P < 0.05]。AKI组与非AKI组术后2～120 h尿L-FABP均显著升高,4 h时差异有统计学意义[2361.41（1036.89~4048.93） ng/mgCr比5246.97（2406.33~7688.21） ng/mgCr,P < 0.05]。AKI组术后2、4、6 h尿NGAL均显著高于非AKI组,差异有统计学意义 [69.02（29.79~237.29）比22.94（8.69~46.23） ng/mgCr,29.34（16.06~536.91）比 12.66（8.91~22.78） ng/mgCr和34.23（11.47~81.26）比11.84（6.57~20.10） ng/mgCr,均P < 0.05]。ROC曲线下面积（AUC）结果显示,与尿L-FABP相比（当4 h截断点为3451.75 ng/mgCr时,AUC为0.760）,尿NGAL对早期诊断AKI具有更高的敏感性和特异性（2、4、6 h的截断点分别为43.02、26.97和17.19 ng/mgCr时,AUC分别为0.766、0.773和0.773）。 结论 尿NGAL在肝移植术后早期AKI的诊断上表现出较高的敏感性和特异性,也许能作为肝移植术后AKI早期诊断的生物学标志物,但仍需要大样本的临床研究加以证实。     

尿液白介素18在冠状动脉介入术后造影剂肾损伤早期诊断中的意义

目的前瞻性研究尿液白介素18（IL-18）在早期预测和诊断冠状动脉造影术后急性肾损伤中的意义。方法收集150例接受冠状动脉造影及介入治疗患者的资料。造影剂肾病（CIN）以传统方法定义。用酶法测术前及术后24 h、48～72 h Scr值。留取患者术前、术后24 h尿液,用ELISA法检测发生CIN患者尿液IL-18、尿N-乙酰-β-D氨基葡萄糖酐酶（NAG）及尿视黄醇结合蛋白（RBP）的水平,并与未发生CIN的患者比较。结果150例患者中13例发生了CIN,发生率为8.7%。使用造影剂后24 h,患者尿液IL-18（ng/L）和NAG（U/L）水平显著升高[分别为15.06（12.21,21.31）比11.62（9.37,13.86）;13.88（7.09,33.23）比10.09 （5.96,16.62）,P均〈0.05];而尿RBP和Scr无显著变化。与非CIN组比较,CIN组术后尿IL-18 （ng/L）显著升高[18.97（13.64,48.57）比14.01（11.91,17.77）,P〈0.05]。相关分析显示,CIN组尿液IL-18与Scr呈正相关（r=0.664,P：0.013）,而尿NAG和RBP与Scr无相关。ROC分析证实,尿液IL-18在CIN早期诊断中的准确性较高,曲线下面积为0.749,P=0.012;当以15.8 ng/L作为诊断截点时,其在CIN诊断中的敏感性和特异性分别为69.2%和74.1%。队列研究结果显示,尿IL-18明显升高患者CIN发病的危险度最高,RR达3.125;而且在CIN患者中,尿IL-18明显上升的构成比最高（P〈0.05）。结论尿IL-18可较Scr更早提示造影剂肾脏损伤的发生,可能为较好的CIN早期诊断标志物。     

尿NGAL对急性Stanford A型主动脉夹层手术后急性肾损伤的早期诊断价值

目的探讨尿液中性粒细胞明胶酶相关脂质转运蛋白(neutrophil gelatinase-associated lipocalin,NGAL)对急性Stanford A型主动脉夹层术后急性肾损伤(acute kidney injury,AKI)的早期诊断价值。方法以2018年1～12月在南京市第一医院诊断为急性Stanford A型主动脉夹层患者50例为研究对象,根据是否发生AKI分为两组:AKI组共27例患者,非AKI组共23例患者。收集术前以及术后2 h尿液标本,进行尿NGAL浓度监测,AKI的诊断采用全球改善肾脏疾病预后(KDIGO)分级诊断标准,采用受试者工作特征(ROC)曲线评估尿NGAL的诊断价值。结果急性Stanford A型主动脉夹层术后AKI的发生率达到54.0%(27/50),两组患者术前血肌酐浓度差异无统计学意义(P0.05),术后2 h血肌酐浓度的差异具有统计学意义(P0.05),而两组尿NGAL浓度在术前监测点差异即显示出统计学意义(P0.05)。术前尿NGAL的浓度诊断AKI的ROC曲线下面积为0.626,当cut-off值为43 ng/mL,敏感性40.7%,特异性95.7%,而术后2 h尿NGAL浓度的ROC曲线下面积为0.655,cut-off值为46.95 ng/mL时,敏感性是63.0%,特异性为78.3%。结论术前以及术后2 h尿NGAL水平可以预测术后AKI的发生,但其早期诊断价值有限。     

肝移植后早期并发急性肾损伤时尿液中肾损伤分子-1的变化及意义

目的 探讨肝移植后早期并发急性肾损伤(AKI)时尿液中肾损伤分子-1(KIM-1)的变化及意义.方法 回顾性分析原位肝移植50例的资料,按照急性肾损伤协作组(AKIN)标准依据受者术后是否发生AKI将受者分为AKI组(27例)和非AKI组(23例),测定两组各设定时间点血清肌酐(SCr)、尿肌酐(UCr)和尿KIM-1的水平,分析尿KIM-1与AKI之间的关系,运用受试者工作特征曲线(ROC)及曲线下面积(AUC)评价依据尿KIM-1诊断AKI的准确性.结果 两组术后24 h时SCr达峰值,AKI组的SCr明显高于非AKI组(P＜0.05),随后均逐渐降至术前水平.门静脉开放后即刻两组的尿KIM-1水平均明显升高,AKI组于门静脉开放2h时尿KIM-1水平达峰值,明显高于非AKI组(P＜0.01),这种差异一直持续至门静脉开放后12 h.若以门静脉开放后2h的尿KIM-1水平14.19 ng/g UCr作为诊断AKI的临界点,其灵敏度为82.6％,特异性为88.9％.结论 尿KIM-1可作为诊断肝移植后AK1的有效指标;对于术前肾功能正常者,术中尿KIM-1的变化可能对早期预测AKI有帮助.     

尿液中性粒细胞明胶酶相关脂质运载蛋白和白细胞介素18水平检测在移植肾功能延迟恢复早期预测中的应用价值

目的 评价尿液中性粒细胞明胶酶相关脂质运载蛋白(NGAL)和白细胞介素18(IL-18)水平检测在早期预测移植肾功能延迟恢复(DGF)中的价值.方法 采用ELISA法,连续监测86例肾移植患者术前和术后12、24 h尿液标本中NGAL,IL-18及视黄醇结合蛋白(RBP)水平,并分析其与DGF的关系. 结果 86例中发生DGF 15例.术后12 h DGF组尿NGAL(ng/mg)水平明显高于非DGF组(1712.7±474.6比863.1±199.8,P<0.001),尿IL-18(ng/mg)水平与非DGF组比较差异无统计学意义(29.2±4.1比28.7±4.2,P>0.05);术后24 h DGF组尿NGAL和IL-18水平均明显高于非DGF组(分别为2905.0±1108.1比911.8±221.0,211.3±34.0比86.9±22.8,均P<0.001);而尿RBP(μg/mmol)(92.7±17.1比92.8±13.8,P>0.05)和SCr值(μmol/L)(608.1±85.5比542.3±99.6,P>0.05)与非DGF组比较差异无统计学意义.ROC曲线下面积分析结果显示,术后12 h尿NGAL曲线下面积为0.90,cut-off值为996.5 ng/mg时,诊断敏感性90.2%,特异性82.6%;术后24 h IL-18曲线下面积为0.76,cut-off值为148.5 ng/mg时,诊断敏感性76.3%,特异性66.4%. 结论 尿NGAL及IL-18水平变化对早期预测DGF发生有重要的临床意义.     

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.     

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.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.