老年全髋关节置换术高位髂筋膜阻滞的意义

[目的]探讨高位髂筋膜阻滞（fascia iliaca compartment block, FICB）在老年全髋关节置换术（total hip arthroplasty,THA）的意义。[方法] 140例老年初次单侧THA患者随机分为两组，70例采用高位FICB联合舒芬太尼患者自控静脉镇痛（patient-controlled intravenous analgesia, PCIA）（复合组），另外70例采用单纯PCIA (PCIA)组。比较两组术后镇痛和临床资料。[结果]复合组术后8、12、24 h的VAS评分[(2.3±0.4) vs (2.6±0.7), P=0.002;(2.7±0.5) vs (3.4±0.7), P<0.001;(3.0±0.7) vs (3.4±0.6), P<0.001]和BCS评分[(3.3±0.5) vs (2.4±0.4), P<0.001;(2.5±0.4) vs (1.9±0.5), P<0.001;(2.9±0.6) vs (2.1±0.6), P<0.001]均显著优于PCIA组。复合组48 h PCIA总按...     

舒芬太尼复合罗哌卡因用于下腹部手术后硬膜外自控镇痛

目的 观察舒芬太尼复合罗哌卡因用于下腹部手术后患者硬膜外自控镇痛(patient-controlled epidural analgesia,PCEA)的效果.方法 下腹部择期手术120例,年龄28 ～66岁,ASA分级Ⅰ、Ⅱ级,应用随机数字表法分为3组(每组40例):0.5 mg/L舒芬太尼复合0.2％罗哌卡因组(Ⅰ组)、5 mg/L芬太尼复合0.2％罗哌卡因组(Ⅱ组)和0.2％罗哌卡因组(Ⅲ组).所有患者术后镇痛均采用PCEA模式,观察镇痛后4、8、16、24、48 h的MAP、HR、VAS评分和Ramsay镇静评分(ramsay sedationscore,RSS)情况,并记录48 h内镇痛泵总按压次数以及恶心、呕吐、皮肤瘙痒及呼吸抑制的发生率.结果 各时点Ⅰ组VAS评分[(1.4±0.4)、(1.6±0.5)、(1.5±0.4)、(1.6±0.3)、(1.3±0.3)分]和Ⅱ组VAS评分[(1.5±0.6)、(1.6±0.4)、(1.7±0.6)、(1.5±0.4)、(1.4±0.6)分]明显低于Ⅲ组[(2.1±0.7)、(2.4±0.6)、(2.4±0.5)、(2.3±0.7)、(2.2±0.8)分](P＜0.05);在8、16、24 h,Ⅰ组RSS[(2.4±0.6)、(2.1±0.9)、(2.4±0.5)分]高于Ⅱ组[(1.4±0.7)、(1.6±0.6)、(1.6±0.4)分]和Ⅲ组RSS[(1.7±0.6)、(1.4±0.3)、(1.6±0.6)](P＜0.05);Ⅰ组和Ⅱ组镇痛泵总按压次数与Ⅲ组比较,差异有统计学意义(分别为3、4、18次,P＜0.05);Ⅰ组和Ⅱ组恶心呕吐的发生率高于Ⅲ组(分别为15％、12.5％、0,P＜0.05);3组皆未发生呼吸抑制.结论 0.5 mg/L舒芬太尼配伍0.2％罗哌卡因用于下腹部手术后PCEA效果确切,且副作用发生率低.     

超声引导下前锯肌平面阻滞对乳腺癌根治术患者术后镇痛的影响

目的探讨超声引导下前锯肌平面(serratus plane,SP)阻滞对乳腺癌根治术患者术后镇痛效果的影响。方法选择择期行全麻下乳腺癌根治术患者40例,年龄45~65岁,ASAⅠ或Ⅱ级,随机分为两组:SP阻滞组(SP组)和对照组(C组),每组20例。麻醉诱导后行超声引导下术侧SP阻滞,SP组注射0.375%罗哌卡因20 ml,C组注射等容量生理盐水,术后均行舒芬太尼PCIA。于术后2、4、8、12、24h行Prince-Henry疼痛评分(PHPS)。记录术中瑞芬太尼用量及术后24h内舒芬太尼用量,24h内PCIA泵有效按压次数(D1)和实际按压次数(D2),计算D1/D2。记录患者不良反应发生情况。结果 SP组PHPS疼痛评分在术后2h[(1.3±0.4)分vs.(3.0±0.5)分]、4h[(1.4±0.5)分vs.(2.9±0.7)分]、8h[(1.7±0.6)分vs.(2.7±0.6)分]明显低于C组(P0.05)。SP组术中瑞芬太尼用量[(287±41)μg vs.(375±66)μg]及术后24h内舒芬太尼用量[(54±17)μg vs.(88±25)μg]明显少于C组,D1/D2值(0.88±0.11vs.0.56±0.17)明显高于C组(P0.05)。两组均未见其他不良反应。结论超声引导下前锯肌平面阻滞能减轻乳腺癌根治术后患者早期疼痛,增强术后镇痛效果,减少围术期阿片类药物的用量。     

舒芬太尼复合右旋美托咪定用于腹腔热灌注化疗术后患者镇痛的效果观察

目的观察舒芬太尼复合右旋美托咪定用于腹腔热灌注化疗(hyperthermic intraperitoneal chemotherapy,HIPC)术后患者镇痛的临床效果。方法选择ASAⅠ~Ⅱ级择期行HIPC 45例,采用随机数字表随机均分为3组,术后使用患者静脉自控镇痛(patients controlled intravenous analgesia,PCIA),背景剂量2 ml/h,按压剂量2 ml/次,负荷量2 ml,锁定时间15min,药液量100 ml,舒芬太尼3.0μg/h(A组)、舒芬太尼2.0μg/h(B组)、舒芬太尼2.0μg/h+右旋美托咪定4.0μg/h(C组)。观察并记录术后即刻1 h(T1)、2 h(T2)、6 h(T3)、12 h(T4)、24 h(T5)、48 h(T6)患者镇痛评分(VAS)、Ramsay镇静评分,PCIA泵按压次数及不良反应。结果 A、C组T3~T6时点VAS评分明显低于B组[T3:(2.9±0.5)分vs.(3.5±0.8)分,q=3.600,P0.05;(2.8±0.6)分vs.(3.5±0.8)分,q=4.200,P0.05。T4:(2.4±0.6)分vs.(2.9±0.7)分,q=3.049,P0.05;(2.3±0.6)分vs.(2.9±0.7)分,q=3.659,P0.05。T5:(1.9±0.6)分vs.(2.5±0.5)分,q=3.838,P0.05;(1.8±0.7)分vs.(2.5±0.5)分,q=4.477,P0.05。T6:(1.6±0.5)分vs.(2.0±0.4)分,q=3.303,P0.05;(1.5±0.5)分vs.(2.0±0.4)分,q=4.129,P0.05]。A组T5、T6时点Ramsay评分明显高于B组[T5:(2.5±0.5)分vs.(2.1±0.5)分,q=2.893,P0.05;T6:(2.3±0.5)分vs.(1.9±0.3)分,q=3.493,P0.05]。B组T3~T6时点Ramsay评分明显低于C组[T3:(2.4±0.5)分vs.(3.1±0.7)分,q=4.477,P0.05;T4:(2.2±0.4)分vs.(2.8±0.7)分,q=4.243,P0.05;T5:(2.1±0.5)分vs.(2.6±0.6)分,q=3.617,P0.05;T6:(1.9±0.3)分vs.(2.4±0.5)分,q=4.367,P0.05]。恶心呕吐发生率A组明显高于C组[46.7%(7/15)vs.6.7%(1/15),χ~2=4.261,P=0.039],B、C组和A、B组无统计学差异(P0.05)。A、C组48 h内按压次数明显少于B组[(5.3±2.6)次vs.(8.4±4.2)次,q=3.662,P0.05;(4.5±2.8)次vs.(8.4±4.2)次,q=4.608,P0.05]。结论右美托咪定用于HIPC术后患者镇痛可减少舒芬太尼使用量,同时降低恶心呕吐发生率。     

地佐辛复合舒芬太尼患者自控静脉镇痛对腹腔镜肝癌切除术后疼痛和炎症反应的影响

目的观察地佐辛复合舒芬太尼患者自控静脉镇痛(PCIA)对腹腔镜肝癌切除术后疼痛和炎症反应的影响。方法选择择期行腹腔镜下肝癌切除术患者60例,男43例,女17例,年龄18~60岁,体重50~80kg,ASAⅠ或Ⅱ级。采用随机数字表法分为舒芬太尼组(S组)和地佐辛复合舒芬太尼组(DS组),每组30例。术毕使用PCIA,S组配方为舒芬太尼2.0μg/kg加托烷司琼5mg加生理盐水配至100ml,DS组配方为地佐辛0.5mg/kg加舒芬太尼2.0μg/kg加托烷司琼5mg加生理盐水配至100 ml。记录术后4、24、48h患者VAS评分、数字镇静评分(numeric sedation scale,NSS)以及术后48h的患者满意度评分。于麻醉诱导前、术毕和术后4、24、48h采集患者颈内静脉血,采用ELISA法检测血清中TNF-α、IL-2和IL-6的浓度。记录患者术后48h内的PCIA泵按压次数及不良反应发生情况。结果术后4、24、48hDS组VAS评分明显低于S组(P0.05);DS组患者满意度评分明显高于S组[(3.9±0.4)分vs.(2.0±0.5)分](P0.05)。两组患者各时点NSS评分差异无统计学意义。与麻醉诱导前比较,术后4、24、48h两组TNF-α和IL-6浓度明显升高,IL-2浓度明显降低(P0.05);术后24、48hDS组TNF-α、IL-6浓度明显低于S组,IL-2浓度明显高于S组(P0.05)。术后48h内DS组PCIA泵按压次数明显少于S组[(2.0±0.7)次vs.(7.2±1.3)次](P0.05)。两组患者不良反应发生率差异无统计学意义。结论地佐辛0.5mg/kg复合舒芬太尼2.0μg/kg患者自控静脉镇痛可提供安全有效的镇痛,并可减轻腹腔镜肝癌切除术后炎症反应。     

右美托咪定复合左布比卡因用于剖宫产术后硬膜外镇痛的临床研究

目的 探索右美托咪定(dexmedetomidine,Dex)联合低浓度左布比卡因在剖宫产术后硬膜外自控镇痛治疗中的应用可行性及对舒芬太尼消耗量的影响. 方法 90例足月孕单胎择期行剖宫产术的孕妇,ASA分级Ⅰ、Ⅱ级,按随机数字表法分为3组(每组30例):对照组(C组),舒芬太尼1.5 μg/kg+0.1％左布比卡因;Dex 1组(D1组),舒芬太尼1.5μg/kg+0.1％左布比卡因+Dex 0.02 μg·kg-1·h-1;Dex 2组(D2组),舒芬太尼1.5 μ.g/kg+0.1％左布比卡因+Dex 0.05 μg·kg1·h-1,各组药物均用生理盐水稀释至150 ml.孕妇均采用L～L4硬膜外腔联合蛛网膜下腔阻滞麻醉,术毕均快速泵注镇痛液2ml,背景输注速度为2ml/h,患者自控镇痛(patient controlled analgesia,PCA)锁定时间15 min,每次2 ml.记录术前产妇的一般资料,手术与麻醉时间,副作用(皮肤瘙痒、恶心、呕吐)的发生率,舒适度(Bruggrmann comfort scale,BCS)评分以及术后4、8、12、24、48 h的VAS评分和Ramsay评分,统计PCA键有效按压次数和48 h舒芬太尼用量. 结果 术后4、8、12、24、48 h,C组Ramsay评分[(2.0±0.5)、(1.7±0.5)、(1.6±0.6)、(1.6±0.5)、(1.8±0.4)分]明显低于D1组[(2.3±0.5)、(2.3±0.6)、(2.1±0.5)、(2.3±0.5)、(2.2±0.5)分]和D2组[(2.3±0.5)、(2.4±0.5)、(2.3±0.5)、(2.4±0.5)、(2.3±0.5)分](P＜0.05或P＜0.01);D1组[(0.5±0.6)、(0.8±0.9)、(0.9±0.9)、(1.0±0.9)、(1.1±0.8)分]和D2组[(0.4±0.6)、(0.5±0.7)、(0.7±0.7)、(0.8±0.8)、(0.9±0.7)分]VAS评分明显低于C组[(1.3±1.0)、(1.5±1.1)、(1.8±1.0)、(1.9±0.7)、(1.9±0.7)分](P＜0.05或P＜0.01).D2组皮肤瘙痒发生率(3.33％)明显低于C组(26.67％)(P＜0.05).D2组BCS评分[(3.1±0.7)分]显著高于C组[(3.1±0.7)分]与D1组[(1.9±0.7)分](P＜0.05或P＜0.01).C组48 h舒芬太尼消耗量[(1.041±0.025) μg/kg]明显大于D1组[(1.020±0.021)μ.g/kg]和D2组[(1.003±0.019) μg/kg](P＜0.01),且D1组比D2组消耗量大(P＜0.05). 结论 小剂量Dex能明显提高左布比卡因和舒芬太尼剖宫产术后的镇痛效果和安全性,具有良好的应用前景.     

不同剂量瑞芬太尼停药后对大鼠热痛觉阈值的影响

目的 探讨静脉持续输注不同剂量瑞芬太尼停药后对大鼠热痛觉阈值的影响,观察其与剂量的关系. 方法 40只健康雄性SD大鼠,采用随机数字表法分为5组,每组8只,建立颈静脉输液模型,R1、R2、R3、R4组分别通过颈静脉持续输注瑞芬太尼0.3、0.6、1.0、1.5 μg· kg-1· min-1,N组(对照组)输注生理盐水0.1 ml·kg1·min-1共4h.各组分别于模型前(T1),模型后(T2),停药后0.5(T3)、1(T4)、2(T5)、24(T6)、48 h(T7)测量大鼠热痛觉阈值. 结果 颈静脉置管前后,大鼠热痛觉阈值比较差异无统计学意义(P＞0.05);T3时点,各组阈值均降至最小,R4组(3.3±0.3)s、R3组(3.6±0.5)s、R2组(3.9±0.3)s和R1组(4.2±0.9)s阈值较T2时点分别降低34.0％、30.8％、13.3％和10.6％,较N组(4.6±0.4)s分别降低28.3％、21.7％、15.2％和8.7％;T4时点,R4组(3.5±0.4)s、R3组(3.7±0.4)s、R2组(4.0±0.4)s和R1组(4.2±0.8)s阈值较T2时点分别降低30.0％、26.0％、11.1％和10.6％,R4组和R3组,在T3[(3.3±0.3)、(3.6±0.5)s]、T4[(3.5±0.4)、(3.7±0.4)s]和T5[(3.9±0.4)、(4.2±0.7)s]时点较T2[(5.0±0.6)、(5.2±0.8)s]时点明显降低,差异有统计学意义(P＜0.05);R2组和R1组T5时点阈值[(4.2±0.6)、(4.4±0.9)s]较T2时点阈值降低6.7％和6.4％;其余与T2比较,差异无统计学意义(P＞0.05). 结论 静脉持续输注瑞芬太尼停药后出现痛觉过敏(opioid-induced hyperalgesia,OIH),输注剂量越大,其热痛觉阈值下降程度越大,OIH越强.     

加速康复外科技术应用于小儿咽部手术临床分析

目的 探讨加速康复外科(enhanced recovery after surgery,ERAS)技术在小儿咽部手术中的应用效果. 方法 择期接受咽部手术的6～12岁患儿60例,按随机数字表法分为ERAS组和传统方法(conservative treatment surgery,CTS)组(每组30例).其中ERAS组在术前宣教、麻醉处理、术后镇痛等方面给予具有循证医学证据支持的优化措施,CTS组采用常规围麻醉期处理.观察术后清醒时及术后2、8、24h时两组患儿血流动力学的变化、躁动评分、镇痛效果(VAS评分)、术后24 h内是否需要补救镇痛、术后24h内恶心呕吐并发症的发生率、住院天数. 结果 两组患儿各时点的生命体征、手术时间差异无统计学意义(P＞0.05);ERAS组各时点的躁动评分[(2.41±0.50)、(2.48±0.67)、(2.39±0.81)、(2.33±0.51)分]、VAS评分[(3.3±0.5)、(3.2±0.5)、(3.0±0.6)、(2.6±0.9)分]、术后补救镇痛率(30％)和术后恶心呕吐发生率(33.3％)均低于CTS组的躁动评分[(3.54±1.01)、(3.63±0.92)、(3.42±0.32)、(3.38±0.20)分]、VAS评分[(5.3±0.4)、(4.9±0.3)、(4.8±0.4)、(3.9±0.5)分]、术后补救镇痛率(50％)和术后恶心呕吐发生率(66.7％)(P＜0.05).ERAS组住院时间[(5.5±0.8)d]也明显短于CTS组[(7.1±0.5)d](P＜0.05).结论 ERAS技术能减轻咽部手术患儿的术后躁动与疼痛,缩短住院时间,促进患儿康复.     

糖尿病患者P物质含量与围手术期不良心血管事件的相关性研究

目的 探讨糖尿病患者血清P物质(substance P,SP)含量变化与围手术期不良心血管事件(adverse cardiovascular event,ACVE)的相关性. 方法 择期行胆囊切除术的患者44例,根据术前有无糖尿病分为两组(每组22例):糖尿病组(DM组)与对照组(C组).记录两组患者术前一般情况(年龄、性别、ASA分级、体重、血脂、肌酐等),术中血糖、心律、HR、BP、ECG、手术时间以及补液量等变化.采用ELISA法测定术前、术毕SP含量以及术前、术后24 h肌钙蛋白Ⅰ(cardiac troponin Ⅰ,cTnⅠ)含量. 结果 DM组患者胆囊切除术围手术期ACVE发生率(68.18％)较C组(36.36％)高(P＜0.05);DM组患者术前、术毕血清SP含量[(1.1 ±0.4)、(1.0±0.5) μg/L]较C组[(1.6±o.7)、(1.3±o.6)ug/L]低(P＜0.05),而术前、术后24 h血清cTnⅠ含量[(1.8±0.6)、(2.4±1.0)μg/L]较C组[(1.2±0.5)、(1.4±0.6)μg/L]高(P＜0.05);根据围手术期有无发生ACVE进行分类,发生ACVE患者SP含量[(1.0±0.5)μg/L]较未发生ACVE患者(non-ACVE,NACVE)SP含量[(1.4±0.7)μg/L]低(P＜0.05).结论 糖尿病患者血清SP含量降低可能与患者围手术期ACVE的发生率有关.     

罗哌卡因与氟比洛芬酯用于淋巴静脉吻合术后镇痛效果的比较

目的探讨罗哌卡因和氟比洛芬酯用于继发性上肢淋巴水肿患者淋巴静脉吻合术后的镇痛效果。方法2014年10月~2016年3月,选择全麻淋巴静脉吻合术45例,随机分为罗哌卡因组(R组)、氟比洛芬酯预处理组(F_1组)和氟比洛芬酯后处理组(F_2组)各15例。R组在手术结束时应用0.2%罗哌卡因10 ml局部浸润麻醉切口,F_1组于麻醉诱导前5 min静注氟比洛芬酯100 mg,F_2组于手术结束前5 min静注氟比洛芬酯100 mg。记录术后1、2、6、12、24和48 h的疼痛视觉模拟评分(visual analogue scale,VAS)和追加镇痛药的例数。结果术后2 h时R组静息痛和运动痛VAS均低于F_1组、F_2组[静息痛(3.4±0.7)分vs.(4.2±0.9)分vs.(4.1±1.0)分,F=3.741,P=0.032;运动痛(3.7±0.6)分vs.(4.6±0.9)分vs.(4.4±1.0)分,F=4.305,P=0.020];术后6 h时R组静息痛VAS低于F_1组、F_2组[(2.7±0.5)分vs.(3.4±0.5)分vs.(3.1±0.6)分,F=5.783,P=0.006]。术后2 h时R组需要使用镇痛药的患者例数少于F_1和F_2组(1例vs.7例vs.5例,χ~2=6.058,P=0.048)。结论淋巴静脉吻合术后罗哌卡因局部浸润麻醉能取得较好的术后镇痛效果。     

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.