维持性血液透析患者颈动脉钙化相关因素分析

目的：探讨慢性肾衰竭维持性血液透析（MHD）患者颈动脉钙化情况并分析相关因素。方法：对35例MHD患者应用彩色B型超声仪观测双侧颈动脉内膜-中膜厚度（IMT）及钙化情况,同时记录透析龄、收缩压、脉压差,抽血检测血钙、磷、血胆固醇、三酰甘油、白蛋白、C反应蛋白（CRP）、甲状旁腺素,并计算钙磷乘积。结果：35例终末期肾病（ESRD）患者18例（51.4%）存在颈动脉钙化。钙化组IMT值较无钙化组显著增高（P〈0.01）,透析龄、收缩压、脉压差、血磷、钙磷乘积、CRP较无钙化组明显增高（P〈0.05）,而钙化组血浆白蛋白较无钙化组显著降低（P〈0.05）。结论：IMT值、透析龄、血磷、钙磷乘积增高是颈动脉钙化的主要影响因素,收缩压、脉压差、CRP升高和低血浆白蛋白与颈动脉钙化密切相关。MHD患者存在较高的颈动脉钙化率。     

维持性血液透析患者主动脉钙化相关影响因素分析

目的：探讨维持性血液透析（MHD）患者主动脉钙化的相关影响因素。方法：采用胸部正位X线成像技术检测183例MHD患者主动脉钙化情况,将入选患者分为主动脉钙化组（A组）和主动脉无钙化组（B组）,透析前抽血检测血钙、血磷、全段甲状旁腺激素（iPTH）、C反应蛋白（CRP）和血清白蛋白（Alb）等指标,并计算钙磷乘积,比较两组年龄、透析龄和血清学指标的差异,将上述指标与主动脉钙化进行相关性分析,并对筛选出来的危险因素进行非条件Logistic回归分析。结果：A组和B组在年龄、透析龄、血磷、钙磷乘积和CRP水平方面,差异均有统计学意义（P〈0.01或P〈0.05）;MHD患者主动脉钙化的相关影响因素包括：年龄、透析龄、血磷、钙磷乘积及CRP;Logistic回归分析表明,年龄、透析龄和血磷是主动脉钙化的独立危险因素（P〈0.01）。结论：MHD患者主动脉钙化相当常见,主动脉钙化与年龄、透析龄、钙磷代谢和炎症状态有关。     

慢性肾脏病患者成纤维细胞生长因子23与心脏瓣膜钙化的关系研究

目的 观察慢性肾脏病(chronic kidney disease,CKD)患者血中成纤维细胞生长因子23(fibroblast growth factor 23,FGF23)水平,探讨CKD患者FGF23的水平与心脏瓣膜钙化之间的关系.方法 选择CKD患者89例为CKD组,28例非CKD患者为对照组;将CKD组患者根据肾脏病/透析的临床实践指南(Kidney Disease Outcome Quality Initiative,K/DOQI),按估算肾小球滤过率(estimated glomerular filtration rate,eGFR)水平分为CKD 1～2期组16例,CKD 3～4期组20例,CKD 5期组16例及CKD 5D期组37例.应用酶联免疫分析法测定血清FGF23,同时测定血清全段甲状旁腺激素水平(parathyroid hormone,iPTH)、血钙、血磷、三酰甘油、血总胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇等指标.所有患者应用超声心动检测心脏瓣膜是否存在钙化.比较对照组及CKD 1～2期组、CKD 3～4期组、CKD 5期组及CKD 5D期组年龄、血钙、血磷、三酰甘油、血总胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇、iPTH、FGF23水平及糖尿病、心血管疾病、瓣膜钙化比例.根据是否存在心脏瓣膜钙化将CKD患者89例分为瓣膜钙化组14例和无瓣膜钙化组75例,比较2组间年龄、相关指标、糖尿病、冠心病及透析所占比例.结果 ①CKD 5期组Log iPTH(2.40±0.26)及CKD 5D期组(2.47±0.20)较对照组(1.57±0.14)、CKD 1～2期组(1.54±0.10)、CKD 3～4期组(1.82±0.29)明显升高(P＜0.001),CKD 5D期组(2.67±0.54)的Log FGF23较对照组(1.37±0.11)、CKD 1～2期组(1.42±0.12)、CKD 3～4期组(1.62±0.26)、CKD 5期组(1.83±0.37)明显升高(P＜0.001).CKD 5D期组的心脏瓣膜钙化比例(12/37)明显高于对照组(2/28)、CKD 1～2期组(2/26)、CKD 3～4期组(1/20)及CKD 5期组(0/16),差异有统计学意义(P＜0.05);②瓣膜钙化组的年龄[(73.3±9.9)岁]、三酰甘油[(4.10±2.09) mmol/L]、Log FGF23 (2.52±0.71)、透析患者所占比例(11/14)较无钙化组的年龄[(64.8±12.6)岁]、三酰甘油[(1.90±1.59)mmol/L]、Log FGF23(1.96±0.62)、透析患者所占比例(26/75)明显升高,差异有统计学意义(P＜0.05);③Logistic回归分析显示,年龄、Log FGF23、血总胆固醇及糖尿病病史是影响心脏瓣膜钙化的独立影响因素.结论 CKD患者血清FGF23升高,且随着肾功能的恶化,FGF23水平呈升高趋势,FGF23升高为心脏瓣膜钙化的危险因素.     

非透析慢性肾脏病患者动脉钙化的影响因素分析

目的探讨非透析慢性肾脏病(chronic kidney disease,CKD)患者动脉钙化的影响因素。方法共收集337例在福建医科大学附属第一医院住院的非透析CKD患者临床资料,包括年龄、性别、体质量指数、血红蛋白、血白蛋白、血碱性磷酸酶、空腹血糖、血尿素氮、血肌酐、血尿酸、总胆固醇、低密度脂蛋白胆固醇、三酰甘油、高密度脂蛋白胆固醇、血钙、血磷、血镁、胱抑素C、估算肾小球滤过率(estimated glomerular filtration rate,eGFR)、全段甲状旁腺素(intact parathyroid hormone,iPTH)、24 h尿蛋白定量、C-反应蛋白(C-reactive protein,CRP)、25羟维生素D、骨钙素、骨密度(腰椎和股骨颈)。并根据胸部CT平扫分为动脉钙化组(包括主动脉钙化或冠状动脉钙化)和非动脉钙化组,对2组患者的临床资料进行统计分析。结果本组非透析CKD患者经影像学检查提示同时具有主动脉钙化和冠状动脉钙化者共68例(占20.2%),仅有主动脉钙化或冠状动脉钙化之一者119例(占35.3%),无动脉钙化者150例(占44.5%);与无动脉钙化组患者比较,动脉钙化组患者具有年龄大、高血压和慢性肾炎病史多见,血三酰甘油、血胱抑素C、血CRP水平高,eGFR水平低,2组之间比较有统计学差异(均P0.05)。采用Spearman直线相关分析,结果表明动脉钙化与低密度脂蛋白胆固醇、血尿素氮、血肌酐、胱抑素C、血尿酸、iPTH呈正相关,与eGFR呈负相关。Logistic回归分析表明,动脉钙化的保护因素为血红蛋白和eGFR。结论血红蛋白水平和eGFR是非透析CKD患者动脉钙化的保护因素。     

甲状旁腺切除术后维持性血液透析患者腹主动脉钙化的改变

目的 观察维持性血液透析(maintenance hemodialysis,MHD)合并继发性甲状旁腺功能亢进(secondary hyperparathyroidism,SHPT)患者行甲状旁腺切除术(parathyroidectomy,PTX)后腹主动脉钙化及生化指标的发展变化.方法 回顾性分析完成2年随访的严重SHPT患者,按是否行PTX分成PTX手术组和非手术组,观察术后2年腹主动脉钙化评分(abdominal aortic calcification score,AACS)、血清全段甲状旁腺素(iPTH)、血钙、血磷等变化.PTX手术组按照术后2年腹主动脉钙化有无进展分为进展组和非进展组,对比两组的年龄、透析龄、iPTH、血钙、血磷、钙磷乘积等指标,分析腹主动脉钙化进展的相关因素.结果 共纳入44例MHD合并SHPT患者,PTX手术组26例,非手术组18例.PTX手术组与非手术组基线资料比较,透析龄差异有统计学意义(P<0.05),而性别、年龄、高血压史等差异均无统计学意义.与术前比较,PTX手术组患者术后2年血iPTH、血钙、血磷均降低(均P<0.05),AACS前后差异无统计学意义.患者术后2年有8例(30.77%)腹主动脉钙化加速进展,8例(30.77%)腹主动脉钙化好转,10例(38.46%)腹主动脉钙化稳定.患者术后2年腹主动脉钙化非进展组iPTH值低于进展组[(20.62+6.44) ng/L比(132.72±76.83) ng/L,P<0.05],而非进展组术前AACS高于进展组[(13.11±2.71)分比(2.00±1.41)分,P<0.05].非手术组患者2年后AACS高于基线水平[(10.44±1.65)分比(8.05±1.26)分,P<0.05],血磷及钙磷乘积显著下降(均P<0.05),iPTH、血钙等水平无明显变化(均P>0.05).Pearson相关分析结果显示,PTX手术组术后2年AACS相对于术前的下降值与iPTH下降值(r=0.534,P=0.012)、血钙下降值(r=0.643,P=0.004)、血磷下降值(r=0.897,P<0.001)、钙磷乘积的下降值(r=0.568,P=0.021)呈正相关,与术前AACS值呈负相关(r=-0.647,P=0.014).结论 小样本资料显示,相比非手术治疗,PTX可长期纠正甲状旁腺素、钙、磷代谢紊乱,并有阻止腹主动脉钙化进展甚至逆转血管钙化的可能,而腹主动脉钙化逆转可能与iPTH、血Ca、血P、钙磷乘积的下降程度相关.     

维持性血液透析患者钙磷代谢及甲状旁腺素水平横断面调查

目的根据透析病人生存质量指南标准调查大理大学第一附属医院维持性血液透析(MHD)患者钙磷代谢及甲状旁腺素的达标率,评价其危险因素,为临床治疗提供依据。方法对我院128例MHD患者的血钙、血磷、血清白蛋白、血清碱性磷酸酶、甲状旁腺素(i PTH)等进行检验,并根据透析病人生存质量指南标准进行达标率统计;对患者年龄(≤45岁组和4 5岁组)、残余尿量(尿量1 0 0 m l/d的无尿组和尿量≥1 0 0 m l/d的有尿组)、透析时间(3年组和≥3年组)、透析充分性(eKt/V≥1.2和e Kt/V1.2)分别分组,并对组间血钙、血磷、钙磷乘积、ALP、i PTH、URR%、e Kt/V等指标进行比较;采用多元逐步回归分析i PTH与年龄、透析时间、血钙、血磷、钙磷乘积、血清白蛋白、碱性磷酸酶、尿素氮、血肌酐、残余尿量等的关系。结果1 2 8例患者中血钙、血磷、钙磷乘积、i PTH达标率分别为4 8.4%、4 2.2%、5 8.6%、2 5%,四项指标均达标的患者12例,占9.38%。≤45岁组和45岁组组间血磷、钙磷乘积、无尿组和有尿组组间i PTH,透析充分组和透析不充分组组间URR%差异有统计学意义(P0.05)。i PTH与透析时间、血钙呈负相关,与血磷、碱性磷酸酶、血肌酐呈正相关。结论本院MHD患者钙磷代谢及甲状旁腺素水平达标率较低,临床上需加强患者宣教,在合理使用磷结合剂、充分透析同时,注意监测总结治疗效果及不良反应,以改善MHD患者的预后。     

不同钙浓度透析液治疗甲状旁腺切除术后低钙血症的探讨

目的观察血液透析患者行甲状旁腺切除术后,使用不同钙浓度透析液纠正术后低钙血症的效果。方法回顾性分析2011年10月至2014年5月我院血液透析中心行甲状旁腺切除术的13例患者,根据术后透析治疗时使用的不同钙浓度透析液,分为A组(使用钙浓度1.50 mmol/L透析液)5例,B组(使用钙浓度1.75 mmol/L透析液)8例。分别观察2组患者术后当日、术后第3、6个月透析前后的血压及透析间期的血钙、血磷、全段甲状旁腺素(intact parathyroid hormone,iPTH),比较数值之间的变化;同时统计2组患者口服钙剂的用量,并通过彩色多普勒超声心脏瓣膜评估及胸部多层螺旋电子计算机断层扫描成像(multi-slice computed tomography,MSCT)所示心脏大血管的影像学表现,比较术前及术后第6个月患者冠状动脉钙化评分分值的变化。结果比较2组单次血液透析治疗时透析前与透析结束后4 h的血钙,2组透析结束后4 h的血钙较透析前均升高,差异有统计学意义(P0.05)。同时分别比较2组透析前与术后第3、6个月时血钙变化,差异有统计学意义(P0.05)。而2组之间透析前的血磷、iPTH无统计学差异(P0.05)。通过6个月调整治疗后,血钙较术后当日明显升高(P0.05),血磷明显下降(P0.05)。术后第6个月时,B组较A组口服钙片的剂量明显减少,血压明显上升(P0.05)。同时术前及术后第6个月心脏瓣膜评估及冠状动脉钙化评分分值无明显变化(P0.05)。结论高钙透析液能更好、更快的纠正术后出现的严重低钙血症,减少维持性钙片的服用剂量,但须注意异位钙化的风险及高血压的发生。     

维持性血液透析患者钙磷代谢紊乱的影响因素及其与肾性贫血的相关性

目的调查我院血液透析中心患者钙磷代谢标志物血钙、血磷、全段甲状旁腺素(intact parathyroid hormone,iPTH)等指标的达标情况,探讨维持性血液透析患者钙磷代谢紊乱的影响因素及其与肾性贫血的关系,以便更好的控制钙磷代谢紊乱并管理贫血。方法研究纳入2010年1月至2015年1月在我院血液透析中心规律行血液透析(透析时间≥3个月)的终末期肾病患者作为研究对象,收集患者年龄、性别、透析时间、透析频率、残余尿量等相关资料及患者血钙、血磷、iPTH、血红蛋白(hemoglobin,Hb)等实验室检查指标,统计我院血液透析中心患者钙磷代谢标志物血钙、血磷、iPTH等各项指标的达标情况。然后分别根据年龄、透析龄、透析频率、残余尿量进行分组,比较各组间钙磷代谢指标的差异性,再分别根据血钙、血磷和iPTH进行分组,采用趋势卡方检验及方差分析比较各组间Hb达标情况。结果①本血液透析中心263例患者中,血钙达标率45.0%,血磷达标率40.1%,iPTH达标率23.7%,与透析预后与实践模式研究第4阶段(Dialysis Outcomes and Practice Pattern Study,DOPPS4)国家达标数据(56.0%、54.5%、32.1%)比较,达标率存在一定差距。②根据透析龄进行分组,透析龄≥3年组平均血钙水平显著高于透析龄3年组平均血钙水平;根据透析频率进行分组,每周2次透析组平均血钙水平显著高于每周≤2次透析组平均血钙水平,血磷水平显著低于每周≤2次透析组。根据残余尿量进行分组,有尿组(尿量≥100 rnl/24 h)钙磷乘积显著低于无尿组。根据年龄分组,年龄45岁组平均血磷水平、iPTH水平、钙磷乘积水平显著低于年龄≤45岁组。③将血钙浓度分为2.1 mmol/L、2.1~2.5 mmol/L、2.5 mmol/L三组。随着血钙增高,Hb达标(≥110 g/L)人数占比越来越大,由38.8%上升至64%,差异有统计学意义(P0.05)。将血磷浓度分为1.13 mmol/L、1.13~1.78 mmol/L、1.78 mmol/L三组,随着血磷增高,Hb达标(110 g/L)人数占比越来越大,由31%上升至53.4%,差异有统计学意义(P0.05)。将血iPTH浓度分为150 ng/L、150~300 ng/L、300 ng/L三组。随着iPTH增高,Hb达标(≥110 g/L)人数占比越来越小,由52.8%下降至36.8%,差异有统计学意义(P0.05)。结论①适当增加透析频率及有效保护残余尿量有助于控制及改善钙磷代谢紊乱。②血钙、血磷浓度上升,有利于维持性血液透析患者Hb的达标。血iPTH浓度上升,不利于维持性血液透析患者Hb的达标。     

维持性血液透析患者心血管并发症及防治对策

目的:探讨维持性血液透析患者发生不良心血管事件的危险因素.方法:选取2010年12月～2011年12月于我科维持性血液透析患者70例.根据不良心血管事件确认标准分为有心血管疾病组45例,无心血管疾病组25例.记录两组患者年龄、性别、原发病、透析龄;同时记录血生化指标:血尿酸、血红蛋白、血浆白蛋白、总蛋白、胆固醇、三酰甘油、高密度脂蛋白、低密度脂蛋白、血钙、血磷、钙磷乘积、全段甲状旁腺素(iPTH)、25 -(OH) D3、碱性磷酸酶、尿素氮、肌酐水平.结果:有心血管疾病组年龄、透析龄明显高于无心血管疾病组(P＜0.01);有心血管疾病组患者血尿酸、血钙水平高于无心血管疾病组(P＜0.05),而血25- (OH)D3水平在有心血管疾病组明显低于无心血管疾病组(P＜0.01);二分类Log istic回归分析显示年龄、透析龄、低密度脂蛋白、钙磷乘积、25-(OH)D3、血尿酸是血液透析患者发生不良心血管事件的重要危险因素.结论:心血管疾病是血液透析患者常见的并发症之一,年龄、透析龄、低密度脂蛋白、钙磷乘积、25- (OH)D3、血尿酸是血透患者发生不良心血管事件的重要危险因素.     

江宁地区持续性非卧床腹膜透析患者退出原因的分析及对策

目的分析南京市江宁地区持续性非卧床腹膜透析(continuous ambulatory peritoneal dialysis,CAPD)患者退出原因及对策。方法回顾性分析2008年1月至2015年5月在南京医科大学附属江宁医院接受腹膜透析置管术进行CAPD 135例患者的临床资料,调查其退出时间和退出原因,同时记录腹膜透析置管时的血红蛋白、血白蛋白、血钾、血钙、血磷、血肌酐、尿素氮和估算肾小球滤过率(estimated glomerular filtration rate,eGFR)等指标,资料收集后根据患者的原发病是否为糖尿病肾脏疾病(diabetic kidney disease,DKD)分为DKD组和非DKD组;另外,根据患者的年龄分为青年组(年龄40岁)、中年组(年龄41~60岁)和老年组(年龄60岁)。根据以上不同的分组进行分析比较。结果本组135例患者,至调查终点维持腹膜透析治疗者83例,退出者52例,退出率为38.52%。男性腹膜透析患者的退出率(30/62,占48.39%)高于女性腹膜透析患者(22/73,占30.14%)。退出腹膜透析的首位和次位原因分别是腹膜透析转血液透析(22/52,占42.38%)及死亡(21/52,占40.38%),而心脑血管系统疾病是导致死亡的最主要的原因(13/21,占61.9%)。DKD组患者开始透析时的血白蛋白、血肌酐、尿素氮、eGFR与非DKD组比较,差异有统计学意义(P0.05)。DKD组退出率(22/37,占59.46%)和病死率(12/37,占32.43%)明显高于非DKI)的退出率(30/98,占30.61%)和病死率(9/98,占9.18%),差异有统计学意义(均P=0.002)。4例肾移植患者均为青年患者。老年腹膜透析患者退出率高(26/53,占49.06%),而其主要退出原因为死亡(18/53,占33.96%);结论心脑血管系统疾病是导致腹膜透析患者退出的重要因素;。DKD的慢性肾衰竭患者应尽早透析并积极加强透析前一体化治疗;老年腹膜透析患者需要加强社会支持、家庭管理;男性腹膜透析患者需要加强宣教、随访以及透析后再培训。     

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.     

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.     

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.